// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Management.Automation;
using System.Management.Automation.Internal;
using System.Management.Automation.Provider;
using System.Management.Automation.Runspaces;
using System.Runtime.InteropServices;
using System.Security;
using System.Security.AccessControl;
using System.Text;
using System.Threading.Tasks;
using System.Xml;
using System.Xml.XPath;

using Microsoft.Win32.SafeHandles;

using Dbg = System.Management.Automation;

namespace Microsoft.PowerShell.Commands
{
    #region FileSystemProvider

    /// <summary>
    /// Defines the implementation of a File System Provider.  This provider
    /// allows for stateless namespace navigation of the file system.
    /// </summary>
    [CmdletProvider(FileSystemProvider.ProviderName, ProviderCapabilities.Credentials | ProviderCapabilities.Filter | ProviderCapabilities.ShouldProcess)]
    [OutputType(typeof(FileSecurity), ProviderCmdlet = ProviderCmdlet.SetAcl)]
    [OutputType(typeof(string), typeof(PathInfo), ProviderCmdlet = ProviderCmdlet.ResolvePath)]
    [OutputType(typeof(PathInfo), ProviderCmdlet = ProviderCmdlet.PushLocation)]
    [OutputType(typeof(PathInfo), ProviderCmdlet = ProviderCmdlet.PopLocation)]
    [OutputType(typeof(byte), typeof(string), ProviderCmdlet = ProviderCmdlet.GetContent)]
    [OutputType(typeof(FileInfo), ProviderCmdlet = ProviderCmdlet.GetItem)]
    [OutputType(typeof(FileInfo), typeof(DirectoryInfo), ProviderCmdlet = ProviderCmdlet.GetChildItem)]
    [OutputType(typeof(FileSecurity), typeof(DirectorySecurity), ProviderCmdlet = ProviderCmdlet.GetAcl)]
    [OutputType(typeof(bool), typeof(string), typeof(FileInfo), typeof(DirectoryInfo), ProviderCmdlet = ProviderCmdlet.GetItem)]
    [OutputType(typeof(bool), typeof(string), typeof(DateTime), typeof(System.IO.FileInfo), typeof(System.IO.DirectoryInfo), ProviderCmdlet = ProviderCmdlet.GetItemProperty)]
    [OutputType(typeof(string), typeof(System.IO.FileInfo), typeof(DirectoryInfo), ProviderCmdlet = ProviderCmdlet.NewItem)]
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Maintainability", "CA1506:AvoidExcessiveClassCoupling", Justification = "This coupling is required")]
    public sealed partial class FileSystemProvider : NavigationCmdletProvider,
                                                     IContentCmdletProvider,
                                                     IPropertyCmdletProvider,
                                                     ISecurityDescriptorCmdletProvider,
                                                     ICmdletProviderSupportsHelp
    {
        // 4MB gives the best results without spiking the resources on the remote connection for file transfers between pssessions.
        // NOTE: The script used to copy file data from session (PSCopyFromSessionHelper) has a
        // maximum fragment size value for security.  If FILETRANSFERSIZE changes make sure the
        // copy script will accommodate the new value.
        private const int FILETRANSFERSIZE = 4 * 1024 * 1024;

        private const int COPY_FILE_ACTIVITY_ID = 0;
        private const int REMOVE_FILE_ACTIVITY_ID = 0;

        // The name of the key in an exception's Data dictionary when attempting
        // to copy an item onto itself.
        private const string SelfCopyDataKey = "SelfCopy";

        /// <summary>
        /// An instance of the PSTraceSource class used for trace output
        /// using "FileSystemProvider" as the category.
        /// </summary>
        [Dbg.TraceSource("FileSystemProvider", "The namespace navigation provider for the file system")]
        private static readonly Dbg.PSTraceSource s_tracer =
            Dbg.PSTraceSource.GetTracer("FileSystemProvider", "The namespace navigation provider for the file system");

        /// <summary>
        /// Gets the name of the provider.
        /// </summary>
        public const string ProviderName = "FileSystem";

        /// <summary>
        /// Initializes a new instance of the FileSystemProvider class. Since this
        /// object needs to be stateless, the constructor does nothing.
        /// </summary>
        public FileSystemProvider()
        {
        }

        private Collection<WildcardPattern> _excludeMatcher = null;

        private static readonly System.IO.EnumerationOptions _enumerationOptions = new System.IO.EnumerationOptions
        {
            MatchType = MatchType.Win32,
            MatchCasing = MatchCasing.CaseInsensitive,
            AttributesToSkip = 0 // Default is to skip Hidden and System files, so we clear this to retain existing behavior
        };

        /// <summary>
        /// Converts all / in the path to \
        /// </summary>
        /// <param name="path">
        /// The path to normalize.
        /// </param>
        /// <returns>
        /// The path with all / normalized to \
        /// </returns>
        internal static string NormalizePath(string path)
        {
            return GetCorrectCasedPath(path.Replace(StringLiterals.AlternatePathSeparator, StringLiterals.DefaultPathSeparator));
        }

        /// <summary>
        /// Get the correct casing for a path.  This method assumes it's being called by NormalizePath()
        /// so that the path is already normalized.
        /// </summary>
        /// <param name="path">
        /// The path to retrieve.
        /// </param>
        /// <returns>
        /// The path with accurate casing if item exists, otherwise it returns path that was passed in.
        /// </returns>
        private static string GetCorrectCasedPath(string path)
        {
            // Only apply to directories where there are issues with some tools if the casing
            // doesn't match the source like git
            if (Directory.Exists(path))
            {
                string exactPath = string.Empty;
                int itemsToSkip = 0;
                if (Utils.PathIsUnc(path))
                {
                    // With the Split method, a UNC path like \\server\share, we need to skip
                    // trying to enumerate the server and share, so skip the first two empty
                    // strings, then server, and finally share name.
                    itemsToSkip = 4;
                }

                var items = path.Split(StringLiterals.DefaultPathSeparator);
                for (int i = 0; i < items.Length; i++)
                {
                    if (itemsToSkip-- > 0)
                    {
                        // This handles the UNC server and share and 8.3 short path syntax
                        exactPath += items[i] + StringLiterals.DefaultPathSeparator;
                        continue;
                    }
                    else if (string.IsNullOrEmpty(exactPath))
                    {
                        // This handles the drive letter or / root path start
                        exactPath = items[i] + StringLiterals.DefaultPathSeparator;
                    }
                    else if (string.IsNullOrEmpty(items[i]) && i == items.Length - 1)
                    {
                        // This handles the trailing slash case
                        if (!exactPath.EndsWith(StringLiterals.DefaultPathSeparator))
                        {
                            exactPath += StringLiterals.DefaultPathSeparator;
                        }

                        break;
                    }
                    else if (items[i].Contains('~'))
                    {
                        // This handles short path names
                        exactPath += StringLiterals.DefaultPathSeparator + items[i];
                    }
                    else
                    {
                        // Use GetFileSystemEntries to get the correct casing of this element
                        try
                        {
                            var entries = Directory.GetFileSystemEntries(exactPath, items[i]);
                            if (entries.Length > 0)
                            {
                                exactPath = entries[0];
                            }
                            else
                            {
                                // If previous call didn't return anything, something failed so we just return the path we were given
                                return path;
                            }
                        }
                        catch
                        {
                            // If we can't enumerate, we stop and just return the original path
                            return path;
                        }
                    }
                }

                return exactPath;
            }
            else
            {
                return path;
            }
        }

        /// <summary>
        /// Checks if the item exist at the specified path. if it exists then creates
        /// appropriate directoryinfo or fileinfo object.
        /// </summary>
        /// <param name="path">
        /// Refers to the item for which we are checking for existence and creating filesysteminfo object.
        /// </param>
        /// <param name="isContainer">
        /// Return true if path points to a directory else returns false.
        /// </param>
        /// <returns>FileInfo or DirectoryInfo object.</returns>
        /// <exception cref="System.ArgumentNullException">
        /// The path is null.
        /// </exception>
        /// <exception cref="System.IO.IOException">
        /// I/O error occurs.
        /// </exception>
        /// <exception cref="System.UnauthorizedAccessException">
        /// An I/O error or a specific type of security error.
        /// </exception>
        private static FileSystemInfo GetFileSystemInfo(string path, out bool isContainer)
        {
            // We use 'FileInfo.Attributes' (not 'FileInfo.Exist')
            // because we want to get exceptions
            // like UnauthorizedAccessException or IOException.
            FileSystemInfo fsinfo = new FileInfo(path);
            var attr = fsinfo.Attributes;
            var exists = (int)attr != -1;
            isContainer = exists && attr.HasFlag(FileAttributes.Directory);

            if (exists)
            {
                if (isContainer)
                {
                    return new DirectoryInfo(path);
                }
                else
                {
                    return fsinfo;
                }
            }

            return null;
        }

        /// <summary>
        /// Overrides the method of CmdletProvider, considering the additional
        /// dynamic parameters of FileSystemProvider.
        /// </summary>
        /// <returns>
        /// whether the filter or attribute filter is set.
        /// </returns>
        internal override bool IsFilterSet()
        {
            bool attributeFilterSet = false;
            GetChildDynamicParameters fspDynamicParam = DynamicParameters as GetChildDynamicParameters;
            if (fspDynamicParam != null)
            {
                attributeFilterSet = (
                    (fspDynamicParam.Attributes != null)
                        || (fspDynamicParam.Directory)
                        || (fspDynamicParam.File)
                        || (fspDynamicParam.Hidden)
                        || (fspDynamicParam.ReadOnly)
                        || (fspDynamicParam.System));
            }

            return (attributeFilterSet || base.IsFilterSet());
        }

        /// <summary>
        /// Gets the dynamic parameters for get-childnames on the
        /// FileSystemProvider.
        /// We currently only support one dynamic parameter,
        /// "Attributes" that returns an enum evaluator for the
        /// given expression.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <returns>
        /// An object that has properties and fields decorated with
        /// parsing attributes similar to a cmdlet class.
        /// </returns>
        protected override object GetChildNamesDynamicParameters(string path)
        {
            return new GetChildDynamicParameters();
        }

        /// <summary>
        /// Gets the dynamic parameters for get-childitems on the
        /// FileSystemProvider.
        /// We currently only support one dynamic parameter,
        /// "Attributes" that returns an enum evaluator for the
        /// given expression.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <param name="recurse">
        /// Ignored.
        /// </param>
        /// <returns>
        /// An object that has properties and fields decorated with
        /// parsing attributes similar to a cmdlet class.
        /// </returns>
        protected override object GetChildItemsDynamicParameters(string path, bool recurse)
        {
            return new GetChildDynamicParameters();
        }

        /// <summary>
        /// Gets the dynamic parameters for Copy-Item on the FileSystemProvider.
        /// </summary>
        /// <param name="path">Source for the copy operation.</param>
        /// <param name="destination">Destination for the copy operation.</param>
        /// <param name="recurse">Whether to recurse.</param>
        /// <returns></returns>
        protected override object CopyItemDynamicParameters(string path, string destination, bool recurse)
        {
            return new CopyItemDynamicParameters();
        }

        #region ICmdletProviderSupportsHelp members

        /// <summary>
        /// Implementation of ICmdletProviderSupportsHelp interface.
        /// Gets provider-specific help content for the corresponding cmdlet.
        /// </summary>
        /// <param name="helpItemName">
        /// Name of command that the help is requested for.
        /// </param>
        /// <param name="path">
        /// Not used here.
        /// </param>
        /// <returns>
        /// The MAML help XML that should be presented to the user.
        /// </returns>
        public string GetHelpMaml(string helpItemName, string path)
        {
            // Get the verb and noun from helpItemName
            //
            string verb = null;
            string noun = null;
            XmlReader reader = null;

            try
            {
                if (!string.IsNullOrEmpty(helpItemName))
                {
                    CmdletInfo.SplitCmdletName(helpItemName, out verb, out noun);
                }
                else
                {
                    return string.Empty;
                }

                if (string.IsNullOrEmpty(verb) || string.IsNullOrEmpty(noun))
                {
                    return string.Empty;
                }

                // Load the help file from the current UI culture subfolder
                XmlDocument document = new XmlDocument();
                CultureInfo currentUICulture = CultureInfo.CurrentUICulture;
                string fullHelpPath = Path.Combine(
                    string.IsNullOrEmpty(this.ProviderInfo.ApplicationBase) ? string.Empty : this.ProviderInfo.ApplicationBase,
                    currentUICulture.ToString(),
                    string.IsNullOrEmpty(this.ProviderInfo.HelpFile) ? string.Empty : this.ProviderInfo.HelpFile);

                XmlReaderSettings settings = new XmlReaderSettings();
                settings.XmlResolver = null;
                reader = XmlReader.Create(fullHelpPath, settings);
                document.Load(reader);

                // Add "msh" and "command" namespaces from the MAML schema
                XmlNamespaceManager nsMgr = new XmlNamespaceManager(document.NameTable);
                nsMgr.AddNamespace("msh", HelpCommentsParser.mshURI);
                nsMgr.AddNamespace("command", HelpCommentsParser.commandURI);

                // Compose XPath query to select the appropriate node based on the cmdlet
                string xpathQuery = string.Format(
                    CultureInfo.InvariantCulture,
                    HelpCommentsParser.ProviderHelpCommandXPath,
                    "[@id='FileSystem']",
                    verb,
                    noun);

                // Execute the XPath query and return its MAML snippet
                XmlNode result = document.SelectSingleNode(xpathQuery, nsMgr);
                if (result != null)
                {
                    return result.OuterXml;
                }
            }
            catch (XmlException)
            {
                return string.Empty;
            }
            catch (PathTooLongException)
            {
                return string.Empty;
            }
            catch (IOException)
            {
                return string.Empty;
            }
            catch (UnauthorizedAccessException)
            {
                return string.Empty;
            }
            catch (NotSupportedException)
            {
                return string.Empty;
            }
            catch (SecurityException)
            {
                return string.Empty;
            }
            catch (XPathException)
            {
                return string.Empty;
            }
            finally
            {
                if (reader != null)
                {
                    ((IDisposable)reader).Dispose();
                }
            }

            return string.Empty;
        }

        #endregion

        #region CmdletProvider members

        /// <summary>
        /// Starts the File System provider. This method sets the Home for the
        /// provider to providerInfo.Home if specified, and %USERPROFILE%
        /// otherwise.
        /// </summary>
        /// <param name="providerInfo">
        /// The ProviderInfo object that holds the provider's configuration.
        /// </param>
        /// <returns>
        /// The updated ProviderInfo object that holds the provider's configuration.
        /// </returns>
        protected override ProviderInfo Start(ProviderInfo providerInfo)
        {
            // Set the home folder for the user
            if (providerInfo != null && string.IsNullOrEmpty(providerInfo.Home))
            {
                // %USERPROFILE% - indicate where a user's home directory is located in the file system.
                string homeDirectory = Environment.GetEnvironmentVariable(Platform.CommonEnvVariableNames.Home);

                if (!string.IsNullOrEmpty(homeDirectory))
                {
                    if (Directory.Exists(homeDirectory))
                    {
                        s_tracer.WriteLine("Home = {0}", homeDirectory);
                        providerInfo.Home = homeDirectory;
                    }
                    else
                    {
                        s_tracer.WriteLine("Not setting home directory {0} - does not exist", homeDirectory);
                    }
                }
            }

            // OneDrive placeholder support (issue #8315)
            // make it so OneDrive placeholders are perceived as such with *all* their attributes accessible
#if !UNIX
            // The placeholder mode management APIs Rtl(Set|Query)(Process|Thread)PlaceholderCompatibilityMode
            // are only supported starting with Windows 10 version 1803 (build 17134)
            if (OperatingSystem.IsWindowsVersionAtLeast(10, 0, 17134, 0))
            {
                // let's be safe, don't change the PlaceHolderCompatibilityMode if the current one is not what we expect
                if (Interop.Windows.RtlQueryProcessPlaceholderCompatibilityMode() == Interop.Windows.PHCM_DISGUISE_PLACEHOLDER)
                {
                    Interop.Windows.RtlSetProcessPlaceholderCompatibilityMode(Interop.Windows.PHCM_EXPOSE_PLACEHOLDERS);
                }
            }
#endif

            return providerInfo;
        }

        #endregion CmdletProvider members

        #region DriveCmdletProvider members

        /// <summary>
        /// Determines if the specified drive can be mounted.
        /// </summary>
        /// <param name="drive">
        /// The drive that is going to be mounted.
        /// </param>
        /// <returns>
        /// The same drive that was passed in, if the drive can be mounted.
        /// null if the drive cannot be mounted.
        /// </returns>
        /// <exception cref="System.ArgumentNullException">
        /// drive is null.
        /// </exception>
        /// <exception cref="System.ArgumentException">
        /// drive root is null or empty.
        /// </exception>
        protected override PSDriveInfo NewDrive(PSDriveInfo drive)
        {
            // verify parameters
            if (drive == null)
            {
                throw PSTraceSource.NewArgumentNullException(nameof(drive));
            }

            if (string.IsNullOrEmpty(drive.Root))
            {
                throw PSTraceSource.NewArgumentException("drive.Root");
            }

            // -Persist switch parameter is supported only for Network paths.
            if (drive.Persist && !PathIsNetworkPath(drive.Root))
            {
                ErrorRecord er = new ErrorRecord(new NotSupportedException(FileSystemProviderStrings.PersistNotSupported), "DriveRootNotNetworkPath", ErrorCategory.InvalidArgument, drive);
                ThrowTerminatingError(er);
            }

            if (IsNetworkMappedDrive(drive))
            {
                // MapNetworkDrive facilitates to map the newly
                // created PS Drive to a network share.
                MapNetworkDrive(drive);
            }

            // The drive is valid if the item exists or the
            // drive is not a fixed drive.  We want to allow
            // a drive to exist for floppies and other such\
            // removable media, even if the media isn't in place.
            bool driveIsFixed = true;
            PSDriveInfo result = null;

            try
            {
                // See if the drive is a fixed drive.
                string pathRoot = Path.GetPathRoot(drive.Root);
                DriveInfo driveInfo = new DriveInfo(pathRoot);

                if (driveInfo.DriveType != DriveType.Fixed)
                {
                    driveIsFixed = false;
                }

                // The current drive is a network drive.
                if (driveInfo.DriveType == DriveType.Network)
                {
                    drive.IsNetworkDrive = true;
                }
            }
            catch (ArgumentException) // swallow ArgumentException incl. ArgumentNullException
            {
            }

            bool validDrive = true;

            if (driveIsFixed)
            {
                // Since the drive is fixed, ensure the root is valid.
                validDrive = SafeDoesPathExist(drive.Root);
            }

            if (validDrive)
            {
                result = drive;
            }
            else
            {
                string error = StringUtil.Format(FileSystemProviderStrings.DriveRootError, drive.Root);
                Exception e = new IOException(error);
                WriteError(new ErrorRecord(e, "DriveRootError", ErrorCategory.ReadError, drive));
            }

            drive.Trace();

            return result;
        }

        /// <summary>
        /// MapNetworkDrive facilitates to map the newly created PS Drive to a network share.
        /// </summary>
        /// <param name="drive">The PSDrive info that would be used to create a new PS drive.</param>
        [SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Justification = "Can be static on Unix but not on Windows.")]

        private void MapNetworkDrive(PSDriveInfo drive)
        {
#if UNIX
            throw new PlatformNotSupportedException();
#else
            // Porting note: mapped network drives are only supported on Windows
            if (drive != null && !string.IsNullOrEmpty(drive.Root))
            {
                // By default the connection is not persisted.
                int connectType = Interop.Windows.CONNECT_NOPERSIST;

                string driveName = null;
                byte[] passwd = null;
                string userName = null;

                if (drive.Persist)
                {
                    if (IsSupportedDriveForPersistence(drive))
                    {
                        connectType = Interop.Windows.CONNECT_UPDATE_PROFILE;
                        driveName = drive.Name + ":";
                        drive.DisplayRoot = drive.Root;
                    }
                    else
                    {
                        ErrorRecord er = new ErrorRecord(new InvalidOperationException(FileSystemProviderStrings.InvalidDriveName), "DriveNameNotSupportedForPersistence", ErrorCategory.InvalidOperation, drive);
                        ThrowTerminatingError(er);
                    }
                }

                // If alternate credentials is supplied then use them to get connected to network share.
                if (drive.Credential != null && !drive.Credential.Equals(PSCredential.Empty))
                {
                    userName = drive.Credential.UserName;

                    passwd = SecureStringHelper.GetData(drive.Credential.Password);
                }

                try
                {
                    int errorCode = Interop.Windows.WNetAddConnection2(driveName, drive.Root, passwd, userName, connectType);

                    if (errorCode != Interop.Windows.ERROR_SUCCESS)
                    {
                        ErrorRecord er = new ErrorRecord(new System.ComponentModel.Win32Exception(errorCode), "CouldNotMapNetworkDrive", ErrorCategory.InvalidOperation, drive);
                        ThrowTerminatingError(er);
                    }

                    if (connectType == Interop.Windows.CONNECT_UPDATE_PROFILE)
                    {
                        // Update the current PSDrive to be a persisted drive.
                        drive.IsNetworkDrive = true;

                        // PsDrive.Root is updated to the name of the Drive for
                        // drives targeting network path and being persisted.
                        drive.Root = driveName + @"\";
                    }
                }
                finally
                {
                    // Clear the password in the memory.
                    if (passwd != null)
                    {
                        Array.Clear(passwd);
                    }
                }
            }
#endif
        }

        /// <summary>
        /// ShouldMapNetworkDrive is a helper function used to detect if the
        /// requested PSDrive to be created has to be mapped to a network drive.
        /// </summary>
        /// <param name="drive"></param>
        /// <returns></returns>
        private static bool IsNetworkMappedDrive(PSDriveInfo drive)
        {
            bool shouldMapNetworkDrive = (drive != null && !string.IsNullOrEmpty(drive.Root) && PathIsNetworkPath(drive.Root)) &&
                                         (drive.Persist || (drive.Credential != null && !drive.Credential.Equals(PSCredential.Empty)));

            return shouldMapNetworkDrive;
        }

        /// <summary>
        /// RemoveDrive facilitates to remove network mapped persisted PSDrvie.
        /// </summary>
        /// <param name="drive">
        /// PSDrive info.
        /// </param>
        /// <returns>PSDrive info.
        /// </returns>
        protected override PSDriveInfo RemoveDrive(PSDriveInfo drive)
        {
#if UNIX
            return drive;
#else
            if (IsNetworkMappedDrive(drive))
            {
                int flags = Interop.Windows.CONNECT_NOPERSIST;
                string driveName;
                if (drive.IsNetworkDrive)
                {
                    // Here we are removing only persisted network drives.
                    flags = Interop.Windows.CONNECT_UPDATE_PROFILE;
                    driveName = drive.Name + ":";
                }
                else
                {
                    // OSGTFS: 608188 PSDrive leaves a connection open after the drive is removed
                    // if a drive is not persisted or networkdrive, we need to use the actual root to remove the drive.
                    driveName = drive.Root;
                }

                // You need to actually remove the drive.
                int errorCode = Interop.Windows.WNetCancelConnection2(driveName, flags, force: true);

                if (errorCode != Interop.Windows.ERROR_SUCCESS)
                {
                    ErrorRecord er = new ErrorRecord(new System.ComponentModel.Win32Exception(errorCode), "CouldRemoveNetworkDrive", ErrorCategory.InvalidOperation, drive);
                    ThrowTerminatingError(er);
                }
            }

            return drive;
#endif
        }

        /// <summary>
        /// IsSupportedDriveForPersistence is a helper method used to
        /// check if the psdrive can be persisted or not.
        /// </summary>
        /// <param name="drive">
        /// PS Drive Info.
        /// </param>
        /// <returns>True if the drive can be persisted or else false.</returns>
        private static bool IsSupportedDriveForPersistence(PSDriveInfo drive)
        {
            bool isSupportedDriveForPersistence = false;
            if (drive != null && !string.IsNullOrEmpty(drive.Name) && drive.Name.Length == 1)
            {
                char driveChar = Convert.ToChar(drive.Name, CultureInfo.InvariantCulture);

                if (char.ToUpperInvariant(driveChar) >= 'A' && char.ToUpperInvariant(driveChar) <= 'Z')
                {
                    isSupportedDriveForPersistence = true;
                }
            }

            return isSupportedDriveForPersistence;
        }

        /// <summary>
        /// Return the UNC path for a given network drive
        /// using the Windows API.
        /// </summary>
        /// <param name="driveName"></param>
        /// <returns></returns>
        internal static string GetUNCForNetworkDrive(string driveName)
        {
#if UNIX
            return driveName;
#else
            string uncPath = null;
            if (!string.IsNullOrEmpty(driveName) && driveName.Length == 1)
            {
                int errorCode = Interop.Windows.GetUNCForNetworkDrive(driveName[0], out uncPath);

                if (errorCode != Interop.Windows.ERROR_SUCCESS)
                {
                    throw new System.ComponentModel.Win32Exception(errorCode);
                }
            }

            return uncPath;
#endif
        }

        /// <summary>
        /// Get the substituted path of a NetWork type MS-DOS device that is created by 'subst' command.
        /// When a MS-DOS device is of NetWork type, it could be:
        ///   1. Substitute a path in a drive that maps to a network location. For example:
        ///         net use z: \\scratch2\scratch\
        ///         subst y: z:\abc\
        ///   2. Substitute a network location directly. For example:
        ///         subst y: \\scratch2\scratch\
        /// </summary>
        /// <param name="driveName"></param>
        /// <returns></returns>
        internal static string GetSubstitutedPathForNetworkDosDevice(string driveName)
        {
#if UNIX
            throw new PlatformNotSupportedException();
        }
#else
            return WinGetSubstitutedPathForNetworkDosDevice(driveName);
        }

        private static string WinGetSubstitutedPathForNetworkDosDevice(string driveName)
        {
            string associatedPath = null;
            if (!string.IsNullOrEmpty(driveName) && driveName.Length == 1)
            {
                associatedPath = Interop.Windows.GetDosDeviceForNetworkPath(driveName[0]);
            }

            return associatedPath;
        }
#endif

        /// <summary>
        /// Get the root path for a network drive or MS-DOS device.
        /// </summary>
        /// <param name="driveInfo"></param>
        /// <returns></returns>
        internal static string GetRootPathForNetworkDriveOrDosDevice(DriveInfo driveInfo)
        {
            Dbg.Diagnostics.Assert(driveInfo.DriveType == DriveType.Network, "Caller should make sure it is a network drive.");

            string driveName = driveInfo.Name.Substring(0, 1);
            string rootPath = null;

            try
            {
                rootPath = GetUNCForNetworkDrive(driveName);
            }
            catch (Win32Exception)
            {
                if (driveInfo.IsReady)
                {
                    // The drive is ready but we failed to find the UNC path based on the drive name.
                    // In this case, it's possibly a MS-DOS device created by 'subst' command that
                    //  - substitutes a network location directly, or
                    //  - substitutes a path in a drive that maps to a network location
                    rootPath = GetSubstitutedPathForNetworkDosDevice(driveName);
                }
                else
                {
                    throw;
                }
            }

            return rootPath;
        }

        /// <summary>
        /// Returns a collection of all logical drives in the system.
        /// </summary>
        /// <returns>
        /// A collection of PSDriveInfo objects, one for each logical drive returned from
        /// System.Environment.GetLogicalDrives().
        /// </returns>
        protected override Collection<PSDriveInfo> InitializeDefaultDrives()
        {
            Collection<PSDriveInfo> results = new Collection<PSDriveInfo>();

            DriveInfo[] logicalDrives = DriveInfo.GetDrives();
            if (logicalDrives != null)
            {
                foreach (DriveInfo newDrive in logicalDrives)
                {
                    // Making sure to obey the StopProcessing.
                    if (Stopping)
                    {
                        results.Clear();
                        break;
                    }

                    // cover everything by the try-catch block, because some of the
                    // DriveInfo properties may throw exceptions
                    try
                    {
                        string newDriveName = newDrive.Name.Substring(0, 1);

                        string description = string.Empty;
                        string root = newDrive.Name;
                        string displayRoot = null;

                        if (newDrive.DriveType == DriveType.Fixed)
                        {
                            try
                            {
                                description = newDrive.VolumeLabel;
                            }
                            // trying to read the volume label may cause an
                            // IOException or SecurityException. Just default
                            // to an empty description.
                            catch (IOException)
                            {
                            }
                            catch (System.Security.SecurityException)
                            {
                            }
                            catch (System.UnauthorizedAccessException)
                            {
                            }
                        }

                        if (newDrive.DriveType == DriveType.Network)
                        {
                            // Platform notes: This is important because certain mount
                            // points on non-Windows are enumerated as drives by .NET, but
                            // the platform itself then has no real network drive support
                            // as required by this context. Solution: check for network
                            // drive support before using it.
#if UNIX
                            continue;
#else
                            displayRoot = GetRootPathForNetworkDriveOrDosDevice(newDrive);
#endif
                        }

                        if (newDrive.DriveType == DriveType.Fixed)
                        {
                            if (!SafeDoesPathExist(newDrive.RootDirectory.FullName))
                            {
                                continue;
                            }

                            root = newDrive.RootDirectory.FullName;
                        }

#if UNIX
                        // Porting notes: On platforms with single root filesystems, ensure
                        // that we add a filesystem with the root "/" to the initial drive list,
                        // otherwise path handling will not work correctly because there
                        // is no : available to separate the filesystems from each other
                        if (root != StringLiterals.DefaultPathSeparatorString
                            && newDriveName == StringLiterals.DefaultPathSeparatorString)
                        {
                            root = StringLiterals.DefaultPathSeparatorString;
                        }
#endif

                        // Porting notes: On non-windows platforms .net can report two
                        // drives with the same root, make sure to only add one of those
                        bool skipDuplicate = false;
                        foreach (PSDriveInfo driveInfo in results)
                        {
                            if (driveInfo.Root == root)
                            {
                                skipDuplicate = true;
                                break;
                            }
                        }

                        if (skipDuplicate)
                        {
                            continue;
                        }

                        // Create a new VirtualDrive for each logical drive
                        PSDriveInfo newPSDriveInfo =
                            new PSDriveInfo(
                                newDriveName,
                                ProviderInfo,
                                root,
                                description,
                                null,
                                displayRoot);

                        // The network drive is detected when PowerShell is launched.
                        // Hence it has been persisted during one of the earlier sessions,
                        if (newDrive.DriveType == DriveType.Network)
                        {
                            newPSDriveInfo.IsNetworkDrive = true;
                        }

                        if (newDrive.DriveType != DriveType.Fixed)
                        {
                            newPSDriveInfo.IsAutoMounted = true;
                        }

                        // Porting notes: on the non-Windows platforms, the drive never
                        // uses : as a separator between drive and path
                        if (!Platform.IsWindows)
                        {
                            newPSDriveInfo.VolumeSeparatedByColon = false;
                        }

                        results.Add(newPSDriveInfo);
                    }
                    // If there are issues accessing properties of the DriveInfo, do
                    // not add the drive
                    catch (IOException)
                    {
                    }
                    catch (System.Security.SecurityException)
                    {
                    }
                    catch (System.UnauthorizedAccessException)
                    {
                    }
                }
            }

            results.Add(
                new PSDriveInfo(
                    DriveNames.TempDrive,
                    ProviderInfo,
                    Path.GetTempPath(),
                    SessionStateStrings.TempDriveDescription,
                    credential: null,
                    displayRoot: null)
            );

            return results;
        }

        #endregion DriveCmdletProvider methods

        #region ItemCmdletProvider methods

        /// <summary>
        /// Retrieves the dynamic parameters required for the Get-Item cmdlet.
        /// </summary>
        /// <param name="path">The path of the file to process.</param>
        /// <returns>An instance of the FileSystemProviderGetItemDynamicParameters class that represents the dynamic parameters.</returns>
        protected override object GetItemDynamicParameters(string path)
        {
            return new FileSystemProviderGetItemDynamicParameters();
        }

        /// <summary>
        /// Determines if the specified path is syntactically and semantically valid.
        /// An example path looks like this
        ///     C:\WINNT\Media\chimes.wav.
        /// </summary>
        /// <param name="path">
        /// The fully qualified path to validate.
        /// </param>
        /// <returns>
        /// True if the path is valid, false otherwise.
        /// </returns>
        protected override bool IsValidPath(string path)
        {
            // Path passed should be fully qualified path.
            if (string.IsNullOrEmpty(path))
            {
                return false;
            }

            // Normalize the path
            path = NormalizePath(path);
            path = EnsureDriveIsRooted(path);

#if !UNIX
            // Remove alternate data stream references
            // See if they've used the inline stream syntax. They have more than one colon.
            int firstColon = path.IndexOf(':');
            int secondColon = path.IndexOf(':', firstColon + 1);
            if (secondColon > 0)
            {
                path = path.Substring(0, secondColon);
            }
#endif

            // Make sure the path is either drive rooted or UNC Path
            if (!IsAbsolutePath(path) && !Utils.PathIsUnc(path))
            {
                return false;
            }

            // Exceptions should only deal with exceptional circumstances,
            // but unfortunately, FileInfo offers no Try() methods that
            // let us check if we _could_ open the file.
            try
            {
                FileInfo testFile = new FileInfo(path);
            }
            catch (Exception e)
            {
                if ((e is ArgumentNullException) ||
                    (e is ArgumentException) ||
                    (e is System.Security.SecurityException) ||
                    (e is UnauthorizedAccessException) ||
                    (e is PathTooLongException) ||
                    (e is NotSupportedException))
                {
                    return false;
                }
                else
                {
                    throw;
                }
            }

            // .NET introduced a change where invalid characters are accepted https://learn.microsoft.com/en-us/dotnet/core/compatibility/2.1#path-apis-dont-throw-an-exception-for-invalid-characters
            // We need to check for invalid characters ourselves.  `Path.GetInvalidFileNameChars()` is a supserset of `Path.GetInvalidPathChars()`

            // Remove drive root first
            string pathWithoutDriveRoot = path.Substring(Path.GetPathRoot(path).Length);

            foreach (string segment in pathWithoutDriveRoot.Split(Path.DirectorySeparatorChar))
            {
                if (PathUtils.ContainsInvalidFileNameChars(segment))
                {
                    return false;
                }
            }

            return true;
        }

        /// <summary>
        /// Gets the item at the specified path.
        /// </summary>
        /// <param name="path">
        /// A fully qualified path representing a file or directory in the
        /// file system.
        /// </param>
        /// <returns>
        /// Nothing.  FileInfo and DirectoryInfo objects are written to the
        /// context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override void GetItem(string path)
        {
            // Validate the argument
            bool isContainer = false;

            if (string.IsNullOrEmpty(path))
            {
                // The parameter was null, throw an exception
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            try
            {
#if !UNIX
                bool retrieveStreams = false;
                FileSystemProviderGetItemDynamicParameters dynamicParameters = null;

                if (DynamicParameters != null)
                {
                    dynamicParameters = DynamicParameters as FileSystemProviderGetItemDynamicParameters;
                    if (dynamicParameters != null)
                    {
                        if ((dynamicParameters.Stream != null) && (dynamicParameters.Stream.Length > 0))
                        {
                            retrieveStreams = true;
                        }
                        else
                        {
                            // See if they've used the inline stream syntax. They have more than one colon.
                            int firstColon = path.IndexOf(':');
                            int secondColon = path.IndexOf(':', firstColon + 1);
                            if (secondColon > 0)
                            {
                                string streamName = path.Substring(secondColon + 1);
                                path = path.Remove(secondColon);

                                retrieveStreams = true;
                                dynamicParameters = new FileSystemProviderGetItemDynamicParameters();
                                dynamicParameters.Stream = new string[] { streamName };
                            }
                        }
                    }
                }
#endif

                FileSystemInfo result = GetFileSystemItem(path, ref isContainer, false);
                if (result != null)
                {
#if !UNIX
                    // If we want to retrieve the file streams, retrieve them.
                    if (retrieveStreams)
                    {
                        foreach (string desiredStream in dynamicParameters.Stream)
                        {
                            // See that it matches the name specified
                            WildcardPattern p = WildcardPattern.Get(desiredStream, WildcardOptions.IgnoreCase | WildcardOptions.CultureInvariant);
                            bool foundStream = false;

                            foreach (AlternateStreamData stream in AlternateDataStreamUtilities.GetStreams(result.FullName))
                            {
                                if (!p.IsMatch(stream.Stream))
                                {
                                    continue;
                                }

                                string outputPath = result.FullName + ":" + stream.Stream;
                                // Alternate data streams can never be containers.
                                WriteItemObject(stream, outputPath, isContainer: false);
                                foundStream = true;
                            }

                            if ((!WildcardPattern.ContainsWildcardCharacters(desiredStream)) && (!foundStream))
                            {
                                string errorMessage = StringUtil.Format(
                                    FileSystemProviderStrings.AlternateDataStreamNotFound, desiredStream, result.FullName);
                                Exception e = new FileNotFoundException(errorMessage, result.FullName);

                                WriteError(new ErrorRecord(
                                    e,
                                    "AlternateDataStreamNotFound",
                                    ErrorCategory.ObjectNotFound,
                                    path));
                            }
                        }
                    }
                    else
#endif
                    {
                        // Otherwise, return the item itself.
                        WriteItemObject(result, result.FullName, isContainer);
                    }
                }
                else
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.ItemNotFound, path);
                    Exception e = new IOException(error);
                    WriteError(new ErrorRecord(
                        e,
                        "ItemNotFound",
                        ErrorCategory.ObjectNotFound,
                        path));
                }
            }
            catch (IOException ioError)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                ErrorRecord er = new ErrorRecord(ioError, "GetItemIOError", ErrorCategory.ReadError, path);
                WriteError(er);
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "GetItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
        }

        private static bool SafeDoesPathExist(string rootDirectory)
        {
            if (Directory.Exists(rootDirectory))
            {
                return true;
            }

            try
            {
                return (File.GetAttributes(rootDirectory) & FileAttributes.Directory) is not 0;
            }
            // In some scenarios (like AppContainers) direct access to the root directory may
            // be prevented, but more specific paths may be accessible.
            catch (UnauthorizedAccessException)
            {
                return true;
            }
            catch
            {
                return false;
            }
        }

        private FileSystemInfo GetFileSystemItem(string path, ref bool isContainer, bool showHidden)
        {
            path = NormalizePath(path);
            FileInfo result = new FileInfo(path);

            var attributes = result.Attributes;
            bool hidden = attributes.HasFlag(FileAttributes.Hidden);
            isContainer = attributes.HasFlag(FileAttributes.Directory);

            // FileInfo allows for a file path to end in a trailing slash, but the resulting object
            // is incomplete.  A trailing slash should indicate a directory.  So if the path ends in a
            // trailing slash and is not a directory, return null
            if (!isContainer && path.EndsWith(Path.DirectorySeparatorChar))
            {
                return null;
            }

            FlagsExpression<FileAttributes> evaluator = null;
            FlagsExpression<FileAttributes> switchEvaluator = null;
            GetChildDynamicParameters fspDynamicParam = DynamicParameters as GetChildDynamicParameters;
            if (fspDynamicParam != null)
            {
                evaluator = fspDynamicParam.Attributes;
                switchEvaluator = FormatAttributeSwitchParameters();
            }

            bool filterHidden = false;           // "Hidden" is specified somewhere in the expression
            bool switchFilterHidden = false;     // "Hidden" is specified somewhere in the parameters

            if (evaluator != null)
            {
                filterHidden = evaluator.ExistsInExpression(FileAttributes.Hidden);
            }

            if (switchEvaluator != null)
            {
                switchFilterHidden = switchEvaluator.ExistsInExpression(FileAttributes.Hidden);
            }

            // if "Hidden" is specified in the attribute filter dynamic parameters
            // also return the object
            if (!isContainer)
            {
                if (!hidden || Force || showHidden || filterHidden || switchFilterHidden)
                {
                    s_tracer.WriteLine("Got file info: {0}", result);
                    return result;
                }
            }
            else
            {
                // Check to see if the path is the root of a file system drive.
                // Since all root paths are hidden we need to show the directory
                // anyway
                bool isRootPath =
                    string.Equals(
                        Path.GetPathRoot(path),
                        result.FullName,
                        StringComparison.OrdinalIgnoreCase);

                // if "Hidden" is specified in the attribute filter dynamic parameters
                // also return the object
                if (isRootPath || !hidden || Force || showHidden || filterHidden || switchFilterHidden)
                {
                    s_tracer.WriteLine("Got directory info: {0}", result);
                    return new DirectoryInfo(path);
                }
            }

            return null;
        }

        /// <summary>
        /// Invokes the item at the path using ShellExecute semantics.
        /// </summary>
        /// <param name="path">
        /// The item to invoke.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override void InvokeDefaultAction(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            string action = FileSystemProviderStrings.InvokeItemAction;

            string resource = StringUtil.Format(FileSystemProviderStrings.InvokeItemResourceFileTemplate, path);

            if (ShouldProcess(resource, action))
            {
                var invokeProcess = new System.Diagnostics.Process();
                // codeql[cs/microsoft/command-line-injection-shell-execution] - This is expected Poweshell behavior where user inputted paths are supported for the context of this method. The user assumes trust for the file path they are specifying. If there is concern for remoting, restricted remoting guidelines should be used.
                invokeProcess.StartInfo.FileName = path;
#if UNIX
                bool useShellExecute = false;
                if (Directory.Exists(path))
                {
                    // Path points to a directory. We have to use xdg-open/open on Linux/macOS.
                    useShellExecute = true;
                }
                else
                {
                    try
                    {
                        // Try Process.Start first. This works for executables on Win/Unix platforms
                        invokeProcess.Start();
                    }
                    catch (Win32Exception ex) when (ex.NativeErrorCode == 13)
                    {
                        // Error code 13 -- Permission denied
                        // The file is possibly not an executable. We try xdg-open/open on Linux/macOS.
                        useShellExecute = true;
                    }
                }

                if (useShellExecute)
                {
                    invokeProcess.StartInfo.UseShellExecute = true;
                    invokeProcess.Start();
                }
#else
                // Use ShellExecute when it's not a headless SKU
                invokeProcess.StartInfo.UseShellExecute = Platform.IsWindowsDesktop;
                invokeProcess.Start();
#endif
            }
        }

        #endregion ItemCmdletProvider members

        #region ContainerCmdletProvider members

        #region GetChildItems
        /// <summary>
        /// Gets the child items of a given directory.
        /// </summary>
        /// <param name="path">
        /// The full path of the directory to enumerate.
        /// </param>
        /// <param name="recurse">
        /// If true, recursively enumerates the child items as well.
        /// </param>
        /// <param name="depth">
        /// Limits the depth of recursion; uint.MaxValue performs full recursion.
        /// </param>
        /// <returns>
        /// Nothing.  FileInfo and DirectoryInfo objects that match the filter are written to the
        /// context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override void GetChildItems(
            string path,
            bool recurse,
            uint depth)
        {
            GetPathItems(path, recurse, depth, false, ReturnContainers.ReturnMatchingContainers);
        }
        #endregion GetChildItems

        #region GetChildNames
        /// <summary>
        /// Gets the path names for all children of the specified
        /// directory that match the given filter.
        /// </summary>
        /// <param name="path">
        /// The full path of the directory to enumerate.
        /// </param>
        /// <param name="returnContainers">
        /// Determines if all containers should be returned or only those containers that match the
        /// filter(s).
        /// </param>
        /// <returns>
        /// Nothing.  Child names are written to the context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override void GetChildNames(
            string path,
            ReturnContainers returnContainers)
        {
            GetPathItems(path, false, uint.MaxValue, true, returnContainers);
        }
        #endregion GetChildNames

        /// <summary>
        /// Gets a new provider-specific path and filter (if any) that corresponds to the given
        /// path.
        /// </summary>
        /// <param name="path">
        /// The path to the item. Unlike most other provider APIs, this path is likely to
        /// contain PowerShell wildcards.
        /// </param>
        /// <param name="filter">
        /// The provider-specific filter currently applied.
        /// </param>
        /// <param name="updatedPath">
        /// The new path to the item.
        /// </param>
        /// <param name="updatedFilter">
        /// The new filter.
        /// </param>
        /// <returns>
        /// True if the path or filter were altered. False otherwise.
        /// </returns>
        /// <remarks>
        /// Makes no attempt to filter if the user has already specified a filter, or
        /// if the path contains directory separators. Those are not supported by the
        /// FileSystem filter.
        /// </remarks>
        protected override bool ConvertPath(
            string path,
            string filter,
            ref string updatedPath,
            ref string updatedFilter)
        {
            // Don't handle full paths, paths that the user is already trying to
            // filter, or paths they are trying to escape.
            if ((!string.IsNullOrEmpty(filter)) ||
                (path.Contains(StringLiterals.DefaultPathSeparator, StringComparison.Ordinal)) ||
                (path.Contains(StringLiterals.AlternatePathSeparator, StringComparison.Ordinal)) ||
                (path.Contains(StringLiterals.EscapeCharacter)))
            {
                return false;
            }

            // We can never actually modify the PowerShell path, as the
            // Win32 filtering support returns items that match the short
            // filename OR long filename.
            //
            // This creates tons of seemingly incorrect matches, such as:
            //
            // *~*:   Matches any file with a long filename
            // *n*:   Matches all files with a long filename, but have been
            //        mapped to a [6][~n].[3] disambiguation bucket
            // *.abc: Matches all files that have an extension that begins
            //        with ABC, since their extension is truncated in the
            //        short filename
            // *.*:   Matches all files and directories, even if they don't
            //        have a dot in their name

            // Our algorithm here is pretty simple. The filesystem can handle
            // * and ? in PowerShell wildcards, just not character ranges [a-z].
            // We replace character ranges with the single-character wildcard, '?'.
            updatedPath = path;
            updatedFilter = System.Text.RegularExpressions.Regex.Replace(path, "\\[.*?\\]", "?");

            return true;
        }

        private void GetPathItems(
            string path,
            bool recurse,
            uint depth,
            bool nameOnly,
            ReturnContainers returnContainers)
        {
            // Verify parameters
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            var fsinfo = GetFileSystemInfo(path, out bool isDirectory);

            if (fsinfo != null)
            {
                if (isDirectory)
                {
                    InodeTracker tracker = null;

                    if (recurse)
                    {
                        GetChildDynamicParameters fspDynamicParam = DynamicParameters as GetChildDynamicParameters;
                        if (fspDynamicParam != null && fspDynamicParam.FollowSymlink)
                        {
                            tracker = new InodeTracker(fsinfo.FullName);
                        }
                    }

                    // Enumerate the directory
                    Dir((DirectoryInfo)fsinfo, recurse, depth, nameOnly, returnContainers, tracker);
                }
                else
                {
                    FlagsExpression<FileAttributes> evaluator = null;
                    FlagsExpression<FileAttributes> switchEvaluator = null;
                    GetChildDynamicParameters fspDynamicParam = DynamicParameters as GetChildDynamicParameters;
                    if (fspDynamicParam != null)
                    {
                        evaluator = fspDynamicParam.Attributes;
                        switchEvaluator = FormatAttributeSwitchParameters();
                    }

                    bool attributeFilter = true;
                    bool switchAttributeFilter = true;
                    bool filterHidden = false;           // "Hidden" is specified somewhere in the expression
                    bool switchFilterHidden = false;     // "Hidden" is specified somewhere in the parameters

                    if (evaluator != null)
                    {
                        attributeFilter = evaluator.Evaluate(fsinfo.Attributes);  // expressions
                        filterHidden = evaluator.ExistsInExpression(FileAttributes.Hidden);
                    }

                    if (switchEvaluator != null)
                    {
                        switchAttributeFilter = switchEvaluator.Evaluate(fsinfo.Attributes);  // switch parameters
                        switchFilterHidden = switchEvaluator.ExistsInExpression(FileAttributes.Hidden);
                    }

                    bool hidden = (fsinfo.Attributes & FileAttributes.Hidden) != 0;

                    // if "Hidden" is explicitly specified anywhere in the attribute filter, then override
                    // default hidden attribute filter.
                    if ((attributeFilter && switchAttributeFilter)
                        && (filterHidden || switchFilterHidden || Force || !hidden))
                    {
                        if (nameOnly)
                        {
                            WriteItemObject(
                                fsinfo.Name,
                                fsinfo.FullName,
                                false);
                        }
                        else
                        {
                            WriteItemObject(fsinfo, path, false);
                        }
                    }
                }
            }
            else
            {
                string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                Exception e = new IOException(error);
                WriteError(new ErrorRecord(
                    e,
                    "ItemDoesNotExist",
                    ErrorCategory.ObjectNotFound,
                    path));
                return;
            }
        }

        private void Dir(
            DirectoryInfo directory,
            bool recurse,
            uint depth,
            bool nameOnly,
            ReturnContainers returnContainers,
            InodeTracker tracker)   // tracker will be non-null only if the user invoked the -FollowSymLinks and -Recurse switch parameters.
        {
            List<IEnumerable<FileSystemInfo>> target = new List<IEnumerable<FileSystemInfo>>();

            try
            {
                if (Filter != null &&
                    Filter.Length > 0)
                {
                    if (returnContainers == ReturnContainers.ReturnAllContainers)
                    {
                        // Don't filter directories
                        target.Add(directory.EnumerateDirectories());
                    }
                    else
                    {
                        // Filter the directories
                        target.Add(directory.EnumerateDirectories(Filter, _enumerationOptions));
                    }

                    // Making sure to obey the StopProcessing.
                    if (Stopping)
                    {
                        return;
                    }

                    // Use the specified filter when retrieving the
                    // children
                    target.Add(directory.EnumerateFiles(Filter, _enumerationOptions));
                }
                else
                {
                    target.Add(directory.EnumerateDirectories());

                    // Making sure to obey the StopProcessing.
                    if (Stopping)
                    {
                        return;
                    }

                    // Don't use a filter to retrieve the children
                    target.Add(directory.EnumerateFiles());
                }

                FlagsExpression<FileAttributes> evaluator = null;
                FlagsExpression<FileAttributes> switchEvaluator = null;

                GetChildDynamicParameters fspDynamicParam = DynamicParameters as GetChildDynamicParameters;
                if (fspDynamicParam != null)
                {
                    evaluator = fspDynamicParam.Attributes;
                    switchEvaluator = FormatAttributeSwitchParameters();
                }

                // Write out the items
                foreach (IEnumerable<FileSystemInfo> childList in target)
                {
                    // On some systems, this is already sorted.  For consistency, always sort again.
                    IEnumerable<FileSystemInfo> sortedChildList = childList.OrderBy(static c => c.Name, StringComparer.CurrentCultureIgnoreCase);

                    foreach (FileSystemInfo filesystemInfo in sortedChildList)
                    {
                        // Making sure to obey the StopProcessing.
                        if (Stopping)
                        {
                            return;
                        }

                        try
                        {
                            bool attributeFilter = true;
                            bool switchAttributeFilter = true;
                            // 'Hidden' is specified somewhere in the expression
                            bool filterHidden = false;
                            // 'Hidden' is specified somewhere in the parameters
                            bool switchFilterHidden = false;

                            if (evaluator != null)
                            {
                                attributeFilter = evaluator.Evaluate(filesystemInfo.Attributes);
                                filterHidden = evaluator.ExistsInExpression(FileAttributes.Hidden);
                            }

                            if (switchEvaluator != null)
                            {
                                switchAttributeFilter = switchEvaluator.Evaluate(filesystemInfo.Attributes);
                                switchFilterHidden = switchEvaluator.ExistsInExpression(FileAttributes.Hidden);
                            }

                            bool hidden = false;
                            if (!Force)
                            {
                                hidden = (filesystemInfo.Attributes & FileAttributes.Hidden) != 0;
                            }

                            // If 'Hidden' is explicitly specified anywhere in the attribute filter, then override
                            // default hidden attribute filter.
                            // If specification is to return all containers, then do not do attribute filter on
                            // the containers.
                            bool attributeSatisfy =
                                ((attributeFilter && switchAttributeFilter) ||
                                    ((returnContainers == ReturnContainers.ReturnAllContainers) &&
                                    ((filesystemInfo.Attributes & FileAttributes.Directory) != 0)));

                            if (attributeSatisfy && (filterHidden || switchFilterHidden || Force || !hidden))
                            {
                                if (nameOnly)
                                {
                                    WriteItemObject(
                                        filesystemInfo.Name,
                                        filesystemInfo.FullName,
                                        false);
                                }
                                else
                                {
                                    if (filesystemInfo is FileInfo)
                                    {
                                        WriteItemObject(filesystemInfo, filesystemInfo.FullName, false);
                                    }
                                    else
                                    {
                                        WriteItemObject(filesystemInfo, filesystemInfo.FullName, true);
                                    }
                                }
                            }
                        }
                        catch (System.IO.FileNotFoundException ex)
                        {
                            WriteError(new ErrorRecord(ex, "DirIOError", ErrorCategory.ReadError, directory.FullName));
                        }
                        catch (UnauthorizedAccessException ex)
                        {
                            WriteError(new ErrorRecord(ex, "DirUnauthorizedAccessError", ErrorCategory.PermissionDenied, directory.FullName));
                        }
                    }
                }

                bool isFilterHiddenSpecified = false;           // "Hidden" is specified somewhere in the expression
                bool isSwitchFilterHiddenSpecified = false;     // "Hidden" is specified somewhere in the parameters

                if (evaluator != null)
                {
                    isFilterHiddenSpecified = evaluator.ExistsInExpression(FileAttributes.Hidden);
                }

                if (switchEvaluator != null)
                {
                    isSwitchFilterHiddenSpecified = switchEvaluator.ExistsInExpression(FileAttributes.Hidden);
                }
                // Recurse into the directories
                // Grab all the directories to recurse
                // into separately from the ones that will get written
                // out.
                if (recurse)
                {
                    // Limiter for recursion
                    if (depth > 0) // this includes special case 'depth == uint.MaxValue' for unlimited recursion
                    {
                        foreach (DirectoryInfo recursiveDirectory in directory.EnumerateDirectories())
                        {
                            // Making sure to obey the StopProcessing.
                            if (Stopping)
                            {
                                return;
                            }

                            bool hidden = false;
                            bool checkReparsePoint = true;
                            if (!Force)
                            {
                                hidden = (recursiveDirectory.Attributes & FileAttributes.Hidden) != 0;

                                // We've already taken the expense of initializing the Attributes property here,
                                // so we can use that to avoid needing to call IsReparsePointLikeSymlink() later.
                                checkReparsePoint = recursiveDirectory.Attributes.HasFlag(FileAttributes.ReparsePoint);
                            }

                            // if "Hidden" is explicitly specified anywhere in the attribute filter, then override
                            // default hidden attribute filter.
                            if (Force || !hidden || isFilterHiddenSpecified || isSwitchFilterHiddenSpecified)
                            {
                                // We only want to recurse into symlinks if
                                //  a) the user has asked to with the -FollowSymLinks switch parameter and
                                //  b) the directory pointed to by the symlink has not already been visited,
                                //     preventing symlink loops.
                                //  c) it is not a reparse point with a target (not OneDrive or an AppX link).
                                if (tracker == null)
                                {
                                    if (checkReparsePoint && InternalSymbolicLinkLinkCodeMethods.IsReparsePointLikeSymlink(recursiveDirectory))
                                    {
                                        continue;
                                    }
                                }
                                else if (!tracker.TryVisitPath(recursiveDirectory.FullName))
                                {
                                    WriteWarning(StringUtil.Format(FileSystemProviderStrings.AlreadyListedDirectory,
                                                                   recursiveDirectory.FullName));
                                    continue;
                                }

                                Dir(recursiveDirectory, recurse, depth - 1, nameOnly, returnContainers, tracker);
                            }
                        }
                    }
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "DirArgumentError", ErrorCategory.InvalidArgument, directory.FullName));
            }
            catch (IOException e)
            {
                // 2004/10/13-JonN removed ResourceActionFailedException wrapper
                WriteError(new ErrorRecord(e, "DirIOError", ErrorCategory.ReadError, directory.FullName));
            }
            catch (UnauthorizedAccessException uae)
            {
                // 2004/10/13-JonN removed ResourceActionFailedException wrapper
                WriteError(new ErrorRecord(uae, "DirUnauthorizedAccessError", ErrorCategory.PermissionDenied, directory.FullName));
            }
        }

        /// <summary>
        /// Create an enum expression evaluator for user-specified attribute filtering
        /// switch parameters.
        /// </summary>
        /// <returns>
        /// If any attribute filtering switch parameters are set,
        /// returns an evaluator that evaluates these parameters.
        /// Otherwise,
        /// returns NULL
        /// </returns>
        private FlagsExpression<FileAttributes> FormatAttributeSwitchParameters()
        {
            FlagsExpression<FileAttributes> switchParamEvaluator = null;
            StringBuilder sb = new StringBuilder();

            if (((GetChildDynamicParameters)DynamicParameters).Directory)
            {
                sb.Append("+Directory");
            }

            if (((GetChildDynamicParameters)DynamicParameters).File)
            {
                sb.Append("+!Directory");
            }

            if (((GetChildDynamicParameters)DynamicParameters).System)
            {
                sb.Append("+System");
            }

            if (((GetChildDynamicParameters)DynamicParameters).ReadOnly)
            {
                sb.Append("+ReadOnly");
            }

            if (((GetChildDynamicParameters)DynamicParameters).Hidden)
            {
                sb.Append("+Hidden");
            }

            string switchParamString = sb.ToString();

            if (!string.IsNullOrEmpty(switchParamString))
            {
                // Remove unnecessary PLUS sign
                switchParamEvaluator = new FlagsExpression<FileAttributes>(switchParamString.Substring(1));
            }

            return switchParamEvaluator;
        }

        /// <summary>
        /// Provides a mode property for FileSystemInfo.
        /// </summary>
        /// <param name="instance">Instance of PSObject wrapping a FileSystemInfo.</param>
        /// <returns>A string representation of the FileAttributes, with one letter per attribute.</returns>
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2001:AvoidCallingProblematicMethods")]
        public static string Mode(PSObject instance) => Mode(instance, excludeHardLink: false);

        /// <summary>
        /// Provides a ModeWithoutHardLink property for FileSystemInfo, without HardLinks for performance reasons.
        /// </summary>
        /// <param name="instance">Instance of PSObject wrapping a FileSystemInfo.</param>
        /// <returns>A string representation of the FileAttributes, with one letter per attribute.</returns>
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2001:AvoidCallingProblematicMethods")]
        public static string ModeWithoutHardLink(PSObject instance) => Mode(instance, excludeHardLink: true);

        private static string Mode(PSObject instance, bool excludeHardLink)
        {
            string ToModeString(FileSystemInfo fileSystemInfo)
            {
                FileAttributes fileAttributes = fileSystemInfo.Attributes;

                bool isReparsePoint = InternalSymbolicLinkLinkCodeMethods.IsReparsePoint(fileSystemInfo);
                bool isLink = isReparsePoint || (!excludeHardLink && InternalSymbolicLinkLinkCodeMethods.IsHardLink(fileSystemInfo));
                if (!isLink)
                {
                    // special casing for the common cases - no allocations
                    switch (fileAttributes)
                    {
                        case FileAttributes.Archive:
                            return "-a---";
                        case FileAttributes.Directory:
                            return "d----";
                        case FileAttributes.Normal:
                            return "-----";
                        case FileAttributes.Directory | FileAttributes.ReadOnly:
                            return "d-r--";
                        case FileAttributes.Archive | FileAttributes.ReadOnly:
                            return "-ar--";
                    }
                }

                bool isDirectory = fileAttributes.HasFlag(FileAttributes.Directory);
                ReadOnlySpan<char> mode = stackalloc char[]
                {
                    isLink ? 'l' : isDirectory ? 'd' : '-',
                    fileAttributes.HasFlag(FileAttributes.Archive) ? 'a' : '-',
                    fileAttributes.HasFlag(FileAttributes.ReadOnly) ? 'r' : '-',
                    fileAttributes.HasFlag(FileAttributes.Hidden) ? 'h' : '-',
                    fileAttributes.HasFlag(FileAttributes.System) ? 's' : '-',
                };
                return new string(mode);
            }

            return instance?.BaseObject is FileSystemInfo fileInfo
                ? ToModeString(fileInfo)
                : string.Empty;
        }

        /// <summary>
        /// Provides a NameString property for FileSystemInfo.
        /// </summary>
        /// <param name="instance">Instance of PSObject wrapping a FileSystemInfo.</param>
        /// <returns>Name if a file or directory, Name -> Target if symlink.</returns>
        public static string NameString(PSObject instance)
        {
            if (instance?.BaseObject is FileSystemInfo fileInfo)
            {
                if (InternalSymbolicLinkLinkCodeMethods.IsReparsePointLikeSymlink(fileInfo))
                {
                    return $"{PSStyle.Instance.FileInfo.SymbolicLink}{fileInfo.Name}{PSStyle.Instance.Reset} -> {fileInfo.LinkTarget}";
                }
                else if (fileInfo.Attributes.HasFlag(FileAttributes.Directory))
                {
                    return $"{PSStyle.Instance.FileInfo.Directory}{fileInfo.Name}{PSStyle.Instance.Reset}";
                }
                else if (PSStyle.Instance.FileInfo.Extension.ContainsKey(fileInfo.Extension))
                {
                    return $"{PSStyle.Instance.FileInfo.Extension[fileInfo.Extension]}{fileInfo.Name}{PSStyle.Instance.Reset}";
                }
                else if ((Platform.IsWindows && CommandDiscovery.PathExtensions.Contains(fileInfo.Extension.ToLower())) ||
                    (!Platform.IsWindows && Platform.NonWindowsIsExecutable(fileInfo.FullName)))
                {
                    return $"{PSStyle.Instance.FileInfo.Executable}{fileInfo.Name}{PSStyle.Instance.Reset}";
                }
                else
                {
                    return fileInfo.Name;
                }
            }

            return string.Empty;
        }

        /// <summary>
        /// Provides a LengthString property for FileSystemInfo.
        /// </summary>
        /// <param name="instance">Instance of PSObject wrapping a FileSystemInfo.</param>
        /// <returns>Length as a string.</returns>
        public static string LengthString(PSObject instance)
        {
            return instance?.BaseObject is FileInfo fileInfo
                ? fileInfo.Attributes.HasFlag(FileAttributes.Offline)
                    ? $"({fileInfo.Length})"
                    : fileInfo.Length.ToString()
                : string.Empty;
        }

        /// <summary>
        /// Provides a LastWriteTimeString property for FileSystemInfo.
        /// </summary>
        /// <param name="instance">Instance of PSObject wrapping a FileSystemInfo.</param>
        /// <returns>LastWriteTime formatted as short date + short time.</returns>
        public static string LastWriteTimeString(PSObject instance)
        {
            return instance?.BaseObject is FileSystemInfo fileInfo
                ? string.Create(CultureInfo.CurrentCulture, $"{fileInfo.LastWriteTime,10:d} {fileInfo.LastWriteTime,8:t}")
                : string.Empty;
        }

        #region RenameItem

        /// <summary>
        /// Renames a file or directory.
        /// </summary>
        /// <param name="path">
        /// The current full path to the file or directory.
        /// </param>
        /// <param name="newName">
        /// The new full path to the file or directory.
        /// </param>
        /// <returns>
        /// Nothing.  The renamed DirectoryInfo or FileInfo object is
        /// written to the context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        ///     newName is null or empty
        /// </exception>
        protected override void RenameItem(
            string path,
            string newName)
        {
            // Check the parameters
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            if (string.IsNullOrEmpty(newName))
            {
                throw PSTraceSource.NewArgumentException(nameof(newName));
            }

            // Clean up "newname" to fix some common usability problems:
            // Rename .\foo.txt .\bar.txt
            // Rename C:\temp\foo.txt C:\temp\bar.txt
            if (newName.StartsWith(".\\", StringComparison.OrdinalIgnoreCase) ||
                newName.StartsWith("./", StringComparison.OrdinalIgnoreCase))
            {
                newName = newName.Remove(0, 2);
            }
            else if (string.Equals(Path.GetDirectoryName(path), Path.GetDirectoryName(newName), StringComparison.OrdinalIgnoreCase))
            {
                newName = Path.GetFileName(newName);
            }

            // Check to see if the target specified is just filename. We dont allow rename to move the file to a different directory.
            // If a path is specified for the newName then we flag that as an error.
            if (!string.Equals(Path.GetFileName(newName), newName, StringComparison.OrdinalIgnoreCase))
            {
                throw PSTraceSource.NewArgumentException(nameof(newName), FileSystemProviderStrings.RenameError);
            }

            // Verify that the target doesn't represent a device name
            if (PathIsReservedDeviceName(newName, "RenameError"))
            {
                return;
            }

            try
            {
                bool isContainer = IsItemContainer(path);

                FileSystemInfo result = null;

                if (isContainer)
                {
                    // Get the DirectoryInfo
                    DirectoryInfo dir = new DirectoryInfo(path);

                    // Generate the new path which the directory will
                    // be renamed to.
                    string parentDirectory = dir.Parent.FullName;
                    string newPath = MakePath(parentDirectory, newName);

                    // Confirm the rename with the user
                    string action = FileSystemProviderStrings.RenameItemActionDirectory;

                    string resource = StringUtil.Format(FileSystemProviderStrings.RenameItemResourceFileTemplate, dir.FullName, newPath);

                    if (ShouldProcess(resource, action))
                    {
                        // Now move the file
                        dir.MoveTo(newPath);

                        result = dir;
                        WriteItemObject(result, result.FullName, isContainer);
                    }
                }
                else
                {
                    // Get the FileInfo
                    FileInfo file = new FileInfo(path);

                    // Generate the new path which the file will be renamed to.
                    string parentDirectory = file.DirectoryName;
                    string newPath = MakePath(parentDirectory, newName);

                    // Confirm the rename with the user
                    string action = FileSystemProviderStrings.RenameItemActionFile;

                    string resource = StringUtil.Format(FileSystemProviderStrings.RenameItemResourceFileTemplate, file.FullName, newPath);

                    if (ShouldProcess(resource, action))
                    {
                        // Now move the file
                        file.MoveTo(newPath);

                        result = file;
                        WriteItemObject(result, result.FullName, isContainer);
                    }
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "RenameItemArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "RenameItemIOError", ErrorCategory.WriteError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "RenameItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
        }

        #endregion RenameItem

        #region NewItem

        /// <summary>
        /// Creates a file or directory with the given path.
        /// </summary>
        /// <param name="path">
        /// The path of the file or directory to create.
        /// </param>
        /// <param name="type">
        /// Specify "file" to create a file.
        /// Specify "directory" or "container" to create a directory.
        /// </param>
        /// <param name="value">
        /// If <paramref name="type"/> is "file" then this parameter becomes the content
        /// of the file to be created.
        /// </param>
        /// <returns>
        /// Nothing.  The new DirectoryInfo or FileInfo object is
        /// written to the context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        ///     type is null or empty.
        /// </exception>
        protected override void NewItem(
            string path,
            string type,
            object value)
        {
            ItemType itemType = ItemType.Unknown;

            // Verify parameters
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            if (string.IsNullOrEmpty(type))
            {
                type = "file";
            }

            path = NormalizePath(path);

            if (Force)
            {
                if (!CreateIntermediateDirectories(path))
                {
                    return;
                }
            }

            itemType = GetItemType(type);

            if (itemType == ItemType.Directory)
            {
                CreateDirectory(path, true);
            }
            else if (itemType == ItemType.File)
            {
                try
                {
                    FileMode fileMode = FileMode.CreateNew;

                    if (Force)
                    {
                        // If force is specified, overwrite the existing
                        // file
                        fileMode = FileMode.Create;
                    }

                    string action = FileSystemProviderStrings.NewItemActionFile;

                    string resource = StringUtil.Format(FileSystemProviderStrings.NewItemActionTemplate, path);

                    if (ShouldProcess(resource, action))
                    {
                        // Create the file with read/write access and
                        // not allowing sharing.
                        using (FileStream newFile =
                            new FileStream(
                                path,
                                fileMode,
                                FileAccess.Write,
                                FileShare.None))
                        {
                            if (value != null)
                            {
                                StreamWriter streamWriter = new StreamWriter(newFile);
                                streamWriter.Write(value.ToString());
                                streamWriter.Flush();
                                streamWriter.Dispose();
                            }
                        }

                        FileInfo fileInfo = new FileInfo(path);
                        WriteItemObject(fileInfo, path, false);
                    }
                }
                catch (IOException exception)
                {
                    // IOException contains specific message about the error occurred and so no need for errordetails.
                    WriteError(new ErrorRecord(exception, "NewItemIOError", ErrorCategory.WriteError, path));
                }
                catch (UnauthorizedAccessException accessException)
                {
                    WriteError(new ErrorRecord(accessException, "NewItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
                }
            }
            else if (itemType == ItemType.SymbolicLink || itemType == ItemType.HardLink)
            {
                string action = null;
                if (itemType == ItemType.SymbolicLink)
                {
                    action = FileSystemProviderStrings.NewItemActionSymbolicLink;
                }
                else if (itemType == ItemType.HardLink)
                {
                    action = FileSystemProviderStrings.NewItemActionHardLink;
                }

                string resource = StringUtil.Format(FileSystemProviderStrings.NewItemActionTemplate, path);

                if (ShouldProcess(resource, action))
                {
                    bool isDirectory = false;
                    string strTargetPath = value?.ToString();

                    if (string.IsNullOrEmpty(strTargetPath))
                    {
                        throw PSTraceSource.NewArgumentNullException(nameof(value));
                    }

                    bool exists = false;

                    // It is legal to create symbolic links to non-existing targets on
                    // both Windows and Linux. It is not legal to create hard links to
                    // non-existing targets on either Windows or Linux.
                    try
                    {
                        if (itemType == ItemType.SymbolicLink)
                        {
                            exists = true;

                            // unify directory separators to be consistent with the rest of PowerShell even on non-Windows platforms;
                            // do this before resolving the target, otherwise e.g. `.\test` would break on Linux, since the combined
                            // path below would be something like `/path/to/cwd/.\test`
                            strTargetPath = strTargetPath.Replace(StringLiterals.AlternatePathSeparator, StringLiterals.DefaultPathSeparator);

                            // check if the target is a file or directory
                            var normalizedTargetPath = Path.Combine(Path.GetDirectoryName(path), strTargetPath);
                            GetFileSystemInfo(normalizedTargetPath, out isDirectory);
                        }
                        else
                        {
                            // for hardlinks we resolve the target to an absolute path
                            if (!IsAbsolutePath(strTargetPath))
                            {
                                strTargetPath = SessionState.Path.GetUnresolvedProviderPathFromPSPath(strTargetPath);
                            }

                            exists = GetFileSystemInfo(strTargetPath, out isDirectory) != null;
                        }
                    }
                    catch (Exception e)
                    {
                        WriteError(new ErrorRecord(e, "AccessException", ErrorCategory.PermissionDenied, strTargetPath));
                        return;
                    }

                    if (!exists)
                    {
                        string message = StringUtil.Format(FileSystemProviderStrings.ItemNotFound, strTargetPath);
                        WriteError(new ErrorRecord(new ItemNotFoundException(message), "ItemNotFound", ErrorCategory.ObjectNotFound, strTargetPath));
                        return;
                    }

                    if (itemType == ItemType.HardLink)
                    {
                        // Hard links can only be to files, not directories.
                        if (isDirectory)
                        {
                            string message = StringUtil.Format(FileSystemProviderStrings.ItemNotFile, strTargetPath);
                            WriteError(new ErrorRecord(new InvalidOperationException(message), "ItemNotFile", ErrorCategory.InvalidOperation, strTargetPath));
                            return;
                        }
                    }

                    bool isSymLinkDirectory = false;
                    bool symLinkExists = false;

                    try
                    {
                        symLinkExists = GetFileSystemInfo(path, out isSymLinkDirectory) != null;
                    }
                    catch (Exception e)
                    {
                        WriteError(new ErrorRecord(e, "AccessException", ErrorCategory.PermissionDenied, path));
                        return;
                    }

                    if (Force)
                    {
                        if (itemType == ItemType.HardLink && string.Equals(path, strTargetPath, StringComparison.OrdinalIgnoreCase))
                        {
                            string message = StringUtil.Format(FileSystemProviderStrings.NewItemTargetIsSameAsLink, path);
                            WriteError(new ErrorRecord(new InvalidOperationException(message), "TargetIsSameAsLink", ErrorCategory.InvalidOperation, path));
                            return;
                        }

                        try
                        {
                            if (!isSymLinkDirectory && symLinkExists)
                            {
                                File.Delete(path);
                            }
                            else if (isSymLinkDirectory && symLinkExists)
                            {
                                Directory.Delete(path);
                            }
                        }
                        catch (Exception exception)
                        {
                            if ((exception is FileNotFoundException) ||
                                (exception is DirectoryNotFoundException) ||
                                (exception is UnauthorizedAccessException) ||
                                (exception is System.Security.SecurityException) ||
                                (exception is ArgumentException) ||
                                (exception is PathTooLongException) ||
                                (exception is NotSupportedException) ||
                                (exception is ArgumentNullException) ||
                                (exception is IOException))
                            {
                                WriteError(new ErrorRecord(exception, "NewItemDeleteIOError", ErrorCategory.WriteError, path));
                            }
                            else
                            {
                                throw;
                            }
                        }
                    }
                    else
                    {
                        if (symLinkExists)
                        {
                            string message = StringUtil.Format(FileSystemProviderStrings.SymlinkItemExists, path);
                            WriteError(new ErrorRecord(new IOException(message), "SymLinkExists", ErrorCategory.ResourceExists, path));
                            return;
                        }
                    }

                    bool success = false;

                    if (itemType == ItemType.SymbolicLink)
                    {
#if UNIX
                        success = Platform.NonWindowsCreateSymbolicLink(path, strTargetPath);
#else
                        success = WinCreateSymbolicLink(path, strTargetPath, isDirectory);
#endif
                    }
                    else if (itemType == ItemType.HardLink)
                    {
#if UNIX
                        success = Platform.NonWindowsCreateHardLink(path, strTargetPath);
#else
                        success = Interop.Windows.CreateHardLink(path, strTargetPath, IntPtr.Zero);
#endif
                    }

                    if (!success)
                    {
                        // Porting note: The Win32Exception will report the correct error on Linux
                        int errorCode = Marshal.GetLastWin32Error();

                        Win32Exception w32Exception = new Win32Exception((int)errorCode);

#if UNIX
                        if (Platform.Unix.GetErrorCategory(errorCode) == ErrorCategory.PermissionDenied)
#else
                        if (errorCode == 1314) // ERROR_PRIVILEGE_NOT_HELD
#endif
                        {
                            string message = FileSystemProviderStrings.ElevationRequired;
                            WriteError(new ErrorRecord(new UnauthorizedAccessException(message, w32Exception), "NewItemSymbolicLinkElevationRequired", ErrorCategory.PermissionDenied, value.ToString()));
                            return;
                        }

                        if (errorCode == 1) // ERROR_INVALID_FUNCTION
                        {
                            string message = null;
                            if (itemType == ItemType.SymbolicLink)
                            {
                                message = FileSystemProviderStrings.SymbolicLinkNotSupported;
                            }
                            else
                            {
                                message = FileSystemProviderStrings.HardLinkNotSupported;
                            }

                            WriteError(new ErrorRecord(new InvalidOperationException(message, w32Exception), "NewItemInvalidOperation", ErrorCategory.InvalidOperation, value.ToString()));
                            return;
                        }

                        throw w32Exception;
                    }
                    else
                    {
                        if (isDirectory)
                        {
                            DirectoryInfo dirInfo = new DirectoryInfo(path);
                            WriteItemObject(dirInfo, path, true);
                        }
                        else
                        {
                            FileInfo fileInfo = new FileInfo(path);
                            WriteItemObject(fileInfo, path, false);
                        }
                    }
                }
            }
            else if (itemType == ItemType.Junction)
            {
                string action = FileSystemProviderStrings.NewItemActionJunction;
                string resource = StringUtil.Format(FileSystemProviderStrings.NewItemActionTemplate, path);

                if (ShouldProcess(resource, action))
                {
                    bool isDirectory = false;
                    string strTargetPath = value?.ToString();

                    bool exists = false;

                   // junctions require an absolute path
                    if (!Path.IsPathRooted(strTargetPath))
                    {
                        WriteError(new ErrorRecord(new ArgumentException(FileSystemProviderStrings.JunctionAbsolutePath), "NotAbsolutePath", ErrorCategory.InvalidArgument, strTargetPath));
                        return;
                    }

                    try
                    {
                        exists = GetFileSystemInfo(strTargetPath, out isDirectory) != null;
                    }
                    catch (Exception e)
                    {
                        WriteError(new ErrorRecord(e, "AccessException", ErrorCategory.PermissionDenied, strTargetPath));
                        return;
                    }

                    if (!exists)
                    {
                        string message = StringUtil.Format(FileSystemProviderStrings.ItemNotFound, strTargetPath);
                        WriteError(new ErrorRecord(new ItemNotFoundException(message), "ItemNotFound", ErrorCategory.ObjectNotFound, strTargetPath));
                        return;
                    }

                    // Junctions can only be directories.
                    if (!isDirectory)
                    {
                        string message = StringUtil.Format(FileSystemProviderStrings.ItemNotDirectory, value);
                        WriteError(new ErrorRecord(new InvalidOperationException(message), "ItemNotDirectory", ErrorCategory.InvalidOperation, value));
                        return;
                    }

                    bool isPathDirectory = false;
                    FileSystemInfo pathDirInfo;

                    try
                    {
                        pathDirInfo = GetFileSystemInfo(path, out isPathDirectory);
                    }
                    catch (Exception e)
                    {
                        WriteError(new ErrorRecord(e, "AccessException", ErrorCategory.PermissionDenied, strTargetPath));
                        return;
                    }

                    bool pathExists = pathDirInfo != null;

                    if (pathExists)
                    {
                        // Junctions can only be directories.
                        if (!isPathDirectory)
                        {
                            string message = StringUtil.Format(FileSystemProviderStrings.ItemNotDirectory, path);
                            WriteError(new ErrorRecord(new InvalidOperationException(message), "ItemNotDirectory", ErrorCategory.InvalidOperation, path));
                            return;
                        }

                        // Junctions cannot have files
                        if (!Force && DirectoryInfoHasChildItems((DirectoryInfo)pathDirInfo))
                        {
                            string message = StringUtil.Format(FileSystemProviderStrings.DirectoryNotEmpty, path);
                            WriteError(new ErrorRecord(new IOException(message), "DirectoryNotEmpty", ErrorCategory.WriteError, path));
                            return;
                        }

                        try
                        {
                            pathDirInfo.Delete();
                        }
                        catch (Exception exception)
                        {
                            if ((exception is DirectoryNotFoundException) ||
                                (exception is UnauthorizedAccessException) ||
                                (exception is System.Security.SecurityException) ||
                                (exception is IOException))
                            {
                                WriteError(new ErrorRecord(exception, "NewItemDeleteIOError", ErrorCategory.WriteError, path));
                            }
                            else
                            {
                                throw;
                            }
                        }
                    }

                    CreateDirectory(path, streamOutput: false);
                    pathDirInfo = new DirectoryInfo(path);

                    try
                    {
                        bool junctionCreated = WinCreateJunction(path, strTargetPath);

                        if (junctionCreated)
                        {
                            WriteItemObject(pathDirInfo, path, true);
                        }
                        else // rollback the directory creation if we created it.
                        {
                            if (!pathExists)
                            {
                                pathDirInfo.Delete();
                            }
                        }
                    }
                    catch (Exception exception)
                    {
                        // rollback the directory creation if it was created.
                        if (!pathExists)
                        {
                            pathDirInfo.Delete();
                        }

                        if ((exception is FileNotFoundException) ||
                                (exception is DirectoryNotFoundException) ||
                                (exception is UnauthorizedAccessException) ||
                                (exception is System.Security.SecurityException) ||
                                (exception is ArgumentException) ||
                                (exception is PathTooLongException) ||
                                (exception is NotSupportedException) ||
                                (exception is ArgumentNullException) ||
                                (exception is Win32Exception) ||
                                (exception is IOException))
                        {
                            WriteError(new ErrorRecord(exception, "NewItemCreateIOError", ErrorCategory.WriteError, path));
                        }
                        else
                        {
                            throw;
                        }
                    }
                }
            }
            else
            {
                throw PSTraceSource.NewArgumentException(nameof(type), FileSystemProviderStrings.UnknownType);
            }
        }

#if !UNIX
        private static bool WinCreateSymbolicLink(string path, string strTargetPath, bool isDirectory)
        {
            // The new AllowUnprivilegedCreate is only available on Win10 build 14972 or newer
            var flags = isDirectory ? Interop.Windows.SymbolicLinkFlags.Directory : Interop.Windows.SymbolicLinkFlags.File;

            if (OperatingSystem.IsWindowsVersionAtLeast(10, 0, 14972, 0))
            {
                flags |= Interop.Windows.SymbolicLinkFlags.AllowUnprivilegedCreate;
            }

            var created = Interop.Windows.CreateSymbolicLink(path, strTargetPath, flags);
            return created;
        }
#endif

        private static bool WinCreateJunction(string path, string strTargetPath)
        {
            bool junctionCreated = InternalSymbolicLinkLinkCodeMethods.CreateJunction(path, strTargetPath);
            return junctionCreated;
        }

        private enum ItemType
        {
            Unknown,
            File,
            Directory,
            SymbolicLink,
            Junction,
            HardLink
        }

        private static ItemType GetItemType(string input)
        {
            ItemType itemType = ItemType.Unknown;

            WildcardPattern typeEvaluator =
                WildcardPattern.Get(input + "*",
                                     WildcardOptions.IgnoreCase |
                                     WildcardOptions.Compiled);

            if (typeEvaluator.IsMatch("directory") ||
                typeEvaluator.IsMatch("container"))
            {
                itemType = ItemType.Directory;
            }
            else if (typeEvaluator.IsMatch("file"))
            {
                itemType = ItemType.File;
            }
            else if (typeEvaluator.IsMatch("symboliclink"))
            {
                itemType = ItemType.SymbolicLink;
            }
            else if (typeEvaluator.IsMatch("junction"))
            {
                itemType = ItemType.Junction;
            }
            else if (typeEvaluator.IsMatch("hardlink"))
            {
                itemType = ItemType.HardLink;
            }

            return itemType;
        }

        /// <summary>
        /// Creates a directory at the specified path.
        /// </summary>
        /// <param name="path">
        /// The path of the directory to create
        /// </param>
        /// <param name="streamOutput">
        /// Determines if the directory should be streamed out after being created.
        /// </param>
        private void CreateDirectory(string path, bool streamOutput)
        {
            Dbg.Diagnostics.Assert(
                !string.IsNullOrEmpty(path),
                "The caller should verify path");

            ErrorRecord error = null;
            if (!Force && ItemExists(path, out error))
            {
                string errorMessage = StringUtil.Format(FileSystemProviderStrings.DirectoryExist, path);
                Exception e = new IOException(errorMessage);

                WriteError(new ErrorRecord(
                    e,
                    "DirectoryExist",
                    ErrorCategory.ResourceExists,
                    path));

                return;
            }

            if (error != null)
            {
                WriteError(error);
                return;
            }

            try
            {
                string action = FileSystemProviderStrings.NewItemActionDirectory;

                string resource = StringUtil.Format(FileSystemProviderStrings.NewItemActionTemplate, path);

                if (ShouldProcess(resource, action))
                {
                    var result = Directory.CreateDirectory(path);

                    if (streamOutput)
                    {
                        // Write the result to the pipeline
                        WriteItemObject(result, path, true);
                    }
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "CreateDirectoryArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
#if UNIX
                if (!Force)
#else
                // Windows error code for invalid characters in file or directory name
                const int ERROR_INVALID_NAME = unchecked((int)0x8007007B);

                // Do not suppress IOException on Windows if it has the specific HResult for invalid characters in directory name
                if (ioException.HResult == ERROR_INVALID_NAME || !Force)
#endif
                {
                    // IOException contains specific message about the error occurred and so no need for errordetails.
                    WriteError(new ErrorRecord(ioException, "CreateDirectoryIOError", ErrorCategory.WriteError, path));
                }
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "CreateDirectoryUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
        }

        private bool CreateIntermediateDirectories(string path)
        {
            bool result = false;

            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            try
            {
                // Push the paths of the missing directories onto a stack such that the highest missing
                // parent in the tree is at the top of the stack.
                Stack<string> missingDirectories = new Stack<string>();

                string previousParent = path;

                do
                {
                    string root = string.Empty;

                    if (PSDriveInfo != null)
                    {
                        root = PSDriveInfo.Root;
                    }

                    string parentPath = GetParentPath(path, root);

                    if (!string.IsNullOrEmpty(parentPath) &&
                        !string.Equals(
                            parentPath,
                            previousParent,
                            StringComparison.OrdinalIgnoreCase))
                    {
                        if (!ItemExists(parentPath))
                        {
                            missingDirectories.Push(parentPath);
                        }
                        else
                        {
                            break;
                        }
                    }
                    else
                    {
                        break;
                    }

                    previousParent = parentPath;
                } while (!string.IsNullOrEmpty(previousParent));

                // Now create the missing directories
                foreach (string directoryPath in missingDirectories)
                {
                    CreateDirectory(directoryPath, false);
                }

                result = true;
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "CreateIntermediateDirectoriesArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "CreateIntermediateDirectoriesIOError", ErrorCategory.WriteError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "CreateIntermediateDirectoriesUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }

            return result;
        }

        #endregion NewItem

        #region RemoveItem

        /// <summary>
        /// Removes the specified file or directory.
        /// </summary>
        /// <param name="path">
        /// The full path to the file or directory to be removed.
        /// </param>
        /// <param name="recurse">
        /// Specifies if the operation should also remove child items.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override void RemoveItem(string path, bool recurse)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            try
            {
                path = NormalizePath(path);

#if !UNIX
                bool removeStreams = false;
                FileSystemProviderRemoveItemDynamicParameters dynamicParameters = null;

                if (DynamicParameters != null)
                {
                    dynamicParameters = DynamicParameters as FileSystemProviderRemoveItemDynamicParameters;
                    if (dynamicParameters != null)
                    {
                        if ((dynamicParameters.Stream != null) && (dynamicParameters.Stream.Length > 0))
                        {
                            removeStreams = true;
                        }
                        else
                        {
                            // See if they've used the inline stream syntax. They have more than one colon.
                            int firstColon = path.IndexOf(':');
                            int secondColon = path.IndexOf(':', firstColon + 1);
                            if (secondColon > 0)
                            {
                                string streamName = path.Substring(secondColon + 1);
                                path = path.Remove(secondColon);

                                removeStreams = true;
                                dynamicParameters = new FileSystemProviderRemoveItemDynamicParameters();
                                dynamicParameters.Stream = new string[] { streamName };
                            }
                        }
                    }
                }
#endif

                FileSystemInfo fsinfo = GetFileSystemInfo(path, out bool iscontainer);
                if (fsinfo == null)
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                    Exception e = new IOException(error);
                    WriteError(new ErrorRecord(e, "ItemDoesNotExist", ErrorCategory.ObjectNotFound, path));
                    return;
                }

                if (Context != null
                    && Context.ExecutionContext.SessionState.PSVariable.Get(SpecialVariables.ProgressPreferenceVarPath.UserPath).Value is ActionPreference progressPreference
                    && progressPreference == ActionPreference.Continue)
                {
                    {
                        Task.Run(() =>
                        {
                            GetTotalFiles(path, recurse);
                        });
                        _removeStopwatch.Start();
                    }
                }

#if UNIX
                if (iscontainer)
                {
                    RemoveDirectoryInfoItem((DirectoryInfo)fsinfo, recurse, Force, true);
                }
                else
                {
                    RemoveFileInfoItem((FileInfo)fsinfo, Force);
                }
#else
                if ((!removeStreams) && iscontainer)
                {
                    RemoveDirectoryInfoItem((DirectoryInfo)fsinfo, recurse, Force, true);
                }
                else
                {
                    // If we want to remove the file streams, retrieve them and remove them.
                    if (removeStreams)
                    {
                        foreach (string desiredStream in dynamicParameters.Stream)
                        {
                            // See that it matches the name specified
                            WildcardPattern p = WildcardPattern.Get(desiredStream, WildcardOptions.IgnoreCase | WildcardOptions.CultureInvariant);
                            bool foundStream = false;

                            foreach (AlternateStreamData stream in AlternateDataStreamUtilities.GetStreams(fsinfo.FullName))
                            {
                                if (!p.IsMatch(stream.Stream))
                                {
                                    continue;
                                }

                                foundStream = true;

                                string action = string.Format(
                                    CultureInfo.InvariantCulture,
                                    FileSystemProviderStrings.StreamAction,
                                    stream.Stream, fsinfo.FullName);
                                if (ShouldProcess(action))
                                {
                                    AlternateDataStreamUtilities.DeleteFileStream(fsinfo.FullName, stream.Stream);
                                }
                            }

                            if ((!WildcardPattern.ContainsWildcardCharacters(desiredStream)) && (!foundStream))
                            {
                                string errorMessage = StringUtil.Format(
                                    FileSystemProviderStrings.AlternateDataStreamNotFound, desiredStream, fsinfo.FullName);
                                Exception e = new FileNotFoundException(errorMessage, fsinfo.FullName);

                                WriteError(new ErrorRecord(
                                    e,
                                    "AlternateDataStreamNotFound",
                                    ErrorCategory.ObjectNotFound,
                                    path));
                            }
                        }
                    }
                    else
                    {
                        RemoveFileInfoItem((FileInfo)fsinfo, Force);
                    }
                }

                if (Stopping || _removedFiles == _totalFiles)
                {
                    _removeStopwatch.Stop();
                    var progress = new ProgressRecord(REMOVE_FILE_ACTIVITY_ID, " ", " ")
                    {
                        RecordType = ProgressRecordType.Completed
                    };
                    WriteProgress(progress);
                }
#endif
            }
            catch (IOException exception)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(exception, "RemoveItemIOError", ErrorCategory.WriteError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "RemoveItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
        }

        /// <summary>
        /// Retrieves the dynamic parameters required for the Remove-Item cmdlet.
        /// </summary>
        /// <param name="path">The path of the file to process.</param>
        /// <param name="recurse">Whether to recurse into containers.</param>
        /// <returns>An instance of the FileSystemProviderRemoveItemDynamicParameters class that represents the dynamic parameters.</returns>
        protected override object RemoveItemDynamicParameters(string path, bool recurse)
        {
            if (!recurse)
            {
                return new FileSystemProviderRemoveItemDynamicParameters();
            }
            else
            {
                return null;
            }
        }

        /// <summary>
        /// Removes a directory from the file system.
        /// </summary>
        /// <param name="directory">
        /// The DirectoryInfo object representing the directory to be removed.
        /// </param>
        /// <param name="recurse">
        /// If true, ShouldProcess will be called for each item in the subtree.
        /// If false, ShouldProcess will only be called for the directory item.
        /// </param>
        /// <param name="force">
        /// If true, attempts to modify the file attributes in case of a failure so that
        /// the file can be removed.
        /// </param>
        /// <param name="rootOfRemoval">
        /// True if the DirectoryInfo being passed in is the root of the tree being removed.
        /// ShouldProcess will be called if this is true or if recurse is true.
        /// </param>
        private void RemoveDirectoryInfoItem(DirectoryInfo directory, bool recurse, bool force, bool rootOfRemoval)
        {
            Dbg.Diagnostics.Assert(directory != null, "Caller should always check directory");

            bool continueRemoval = true;

            // We only want to confirm the removal if this is the root of the
            // tree being removed or the recurse flag is specified.
            if (rootOfRemoval || recurse)
            {
                // Confirm the user wants to remove the directory
                string action = FileSystemProviderStrings.RemoveItemActionDirectory;
                continueRemoval = ShouldProcess(directory.FullName, action);
            }

            if (InternalSymbolicLinkLinkCodeMethods.IsReparsePointLikeSymlink(directory))
            {
                void WriteErrorHelper(Exception exception)
                {
                    WriteError(new ErrorRecord(exception, errorId: "DeleteSymbolicLinkFailed", ErrorCategory.WriteError, directory));
                }

                try
                {
                    if (InternalTestHooks.OneDriveTestOn)
                    {
                        WriteErrorHelper(new IOException());
                        return;
                    }
                    else
                    {
                        // Name surrogates should just be detached.
                        directory.Delete();
                    }
                }
                catch (Exception e)
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.CannotRemoveItem, directory.FullName, e.Message);
                    var exception = new IOException(error, e);
                    WriteErrorHelper(exception);
                }

                return;
            }

            if (continueRemoval)
            {
                // Loop through each of the contained directories and recurse into them for
                // removal.
                foreach (DirectoryInfo childDir in directory.EnumerateDirectories())
                {
                    // Making sure to obey the StopProcessing.
                    if (Stopping)
                    {
                        return;
                    }

                    if (childDir != null)
                    {
                        RemoveDirectoryInfoItem(childDir, recurse, force, false);
                    }
                }

                // Loop through each of the contained files and remove them.
                IEnumerable<FileInfo> files = null;

                if (!string.IsNullOrEmpty(Filter))
                {
                    files = directory.EnumerateFiles(Filter);
                }
                else
                {
                    files = directory.EnumerateFiles();
                }

                foreach (FileInfo file in files)
                {
                    // Making sure to obey the StopProcessing.
                    if (Stopping)
                    {
                        return;
                    }

                    if (file != null)
                    {
                        long fileBytesSize = file.Length;

                        if (recurse)
                        {
                            // When recurse is specified we need to confirm each
                            // item before removal.
                            RemoveFileInfoItem(file, force);
                        }
                        else
                        {
                            // When recurse is not specified just delete all the
                            // subitems without confirming with the user.
                            RemoveFileSystemItem(file, force);
                        }

                        if (_totalFiles > 0)
                        {
                            _removedFiles++;
                            _removedBytes += fileBytesSize;
                            if (_removeStopwatch.Elapsed.TotalSeconds > ProgressBarDurationThreshold)
                            {
                                double speed = _removedBytes / 1024 / 1024 / _removeStopwatch.Elapsed.TotalSeconds;
                                var progress = new ProgressRecord(
                                    REMOVE_FILE_ACTIVITY_ID,
                                    StringUtil.Format(FileSystemProviderStrings.RemovingLocalFileActivity, _removedFiles, _totalFiles),
                                    StringUtil.Format(FileSystemProviderStrings.RemovingLocalBytesStatus, Utils.DisplayHumanReadableFileSize(_removedBytes), Utils.DisplayHumanReadableFileSize(_totalBytes), speed)
                                );
                                var percentComplete = _totalBytes != 0 ? (int)Math.Min(_removedBytes * 100 / _totalBytes, 100) : 100;
                                progress.PercentComplete = percentComplete;
                                progress.RecordType = ProgressRecordType.Processing;
                                WriteProgress(progress);
                            }
                        }
                    }
                }

                // Check to see if the item has children
                bool hasChildren = DirectoryInfoHasChildItems(directory);

                if (hasChildren && !force)
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.DirectoryNotEmpty, directory.FullName);
                    Exception e = new IOException(error);
                    WriteError(new ErrorRecord(e, "DirectoryNotEmpty", ErrorCategory.WriteError, directory));
                }
                else // !hasChildren || force
                {
                    // Finally, remove the directory
                    RemoveFileSystemItem(directory, force);
                }
            }
        }

        /// <summary>
        /// Removes a file from the file system.
        /// </summary>
        /// <param name="file">
        /// The FileInfo object representing the file to be removed.
        /// </param>
        /// <param name="force">
        /// If true, attempts to modify the file attributes in case of a failure so that
        /// the file can be removed.
        /// </param>
        private void RemoveFileInfoItem(FileInfo file, bool force)
        {
            Dbg.Diagnostics.Assert(
                file != null,
                "Caller should always check file");

            string action = FileSystemProviderStrings.RemoveItemActionFile;

            if (ShouldProcess(file.FullName, action))
            {
                RemoveFileSystemItem(file, force);
            }
        }

        /// <summary>
        /// Removes the file system object from the file system.
        /// </summary>
        /// <param name="fileSystemInfo">
        /// The FileSystemInfo object representing the file or directory to be removed.
        /// </param>
        /// <param name="force">
        /// If true, the readonly and hidden attributes will be masked off in the case of
        /// an error, and the removal will be attempted again. If false, exceptions are
        /// written to the error pipeline.
        /// </param>
        private void RemoveFileSystemItem(FileSystemInfo fileSystemInfo, bool force)
        {
            Dbg.Diagnostics.Assert(
                fileSystemInfo != null,
                "Caller should always check fileSystemInfo");

            // First check if we can delete this file when force is not specified.
            if (!Force &&
                (fileSystemInfo.Attributes & (FileAttributes.Hidden | FileAttributes.System | FileAttributes.ReadOnly)) != 0)
            {
                string error = StringUtil.Format(FileSystemProviderStrings.PermissionError);
                Exception e = new IOException(error);

                ErrorDetails errorDetails =
                    new ErrorDetails(this, "FileSystemProviderStrings",
                        "CannotRemoveItem",
                        fileSystemInfo.FullName,
                        e.Message);

                ErrorRecord errorRecord = new ErrorRecord(e, "RemoveFileSystemItemUnAuthorizedAccess", ErrorCategory.PermissionDenied, fileSystemInfo);
                errorRecord.ErrorDetails = errorDetails;

                WriteError(errorRecord);
                return;
            }

            // Store the old attributes in case we fail to delete
            FileAttributes oldAttributes = fileSystemInfo.Attributes;
            bool attributeRecoveryRequired = false;

            try
            {
                // Try to delete the item.  Strip any problematic attributes
                // if they've specified force.
                if (force)
                {
                    fileSystemInfo.Attributes &= ~(FileAttributes.Hidden | FileAttributes.ReadOnly | FileAttributes.System);
                    attributeRecoveryRequired = true;
                }

                fileSystemInfo.Delete();

                if (force)
                {
                    attributeRecoveryRequired = false;
                }
            }
            catch (Exception fsException)
            {
                ErrorDetails errorDetails =
                    new ErrorDetails(this, "FileSystemProviderStrings",
                        "CannotRemoveItem",
                        fileSystemInfo.FullName,
                        fsException.Message);

                if ((fsException is System.Security.SecurityException) ||
                    (fsException is UnauthorizedAccessException))
                {
                    ErrorRecord errorRecord = new ErrorRecord(fsException, "RemoveFileSystemItemUnAuthorizedAccess", ErrorCategory.PermissionDenied, fileSystemInfo);
                    errorRecord.ErrorDetails = errorDetails;

                    WriteError(errorRecord);
                }
                else if (fsException is ArgumentException)
                {
                    ErrorRecord errorRecord = new ErrorRecord(fsException, "RemoveFileSystemItemArgumentError", ErrorCategory.InvalidArgument, fileSystemInfo);
                    errorRecord.ErrorDetails = errorDetails;

                    WriteError(errorRecord);
                }
                else if ((fsException is IOException) ||
                    (fsException is FileNotFoundException) ||
                    (fsException is DirectoryNotFoundException))
                {
                    ErrorRecord errorRecord = new ErrorRecord(fsException, "RemoveFileSystemItemIOError", ErrorCategory.WriteError, fileSystemInfo);
                    errorRecord.ErrorDetails = errorDetails;

                    WriteError(errorRecord);
                }
                else
                {
                    throw;
                }
            }
            finally
            {
                if (attributeRecoveryRequired)
                {
                    try
                    {
                        if (fileSystemInfo.Exists)
                        {
                            fileSystemInfo.Attributes = oldAttributes;
                        }
                    }
                    catch (Exception attributeException)
                    {
                        if ((attributeException is System.IO.DirectoryNotFoundException) ||
                            (attributeException is System.Security.SecurityException) ||
                            (attributeException is System.ArgumentException) ||
                            (attributeException is System.IO.FileNotFoundException) ||
                            (attributeException is System.IO.IOException))
                        {
                            ErrorDetails attributeDetails = new ErrorDetails(
                                this, "FileSystemProviderStrings",
                                    "CannotRestoreAttributes",
                                    fileSystemInfo.FullName,
                                    attributeException.Message);

                            ErrorRecord errorRecord = new ErrorRecord(attributeException, "RemoveFileSystemItemCannotRestoreAttributes", ErrorCategory.PermissionDenied, fileSystemInfo);
                            errorRecord.ErrorDetails = attributeDetails;

                            WriteError(errorRecord);
                        }
                        else
                            throw;
                    }
                }
            }
        }

        #endregion RemoveItem

        #region ItemExists

        /// <summary>
        /// Determines if a file or directory exists at the specified path.
        /// </summary>
        /// <param name="path">
        /// The path of the item to check.
        /// </param>
        /// <returns>
        /// True if a file or directory exists at the specified path, false otherwise.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override bool ItemExists(string path)
        {
            ErrorRecord error = null;
            bool result = ItemExists(path, out error);

            if (error != null)
            {
                WriteError(error);
            }

            return result;
        }

        /// <summary>
        /// Implementation of ItemExists for the provider. This implementation
        /// allows the caller to decide if it wants to WriteError or not based
        /// on the returned ErrorRecord.
        /// </summary>
        /// <param name="path">
        /// The path of the object to check
        /// </param>
        /// <param name="error">
        /// An error record is returned in this parameter if there was an error.
        /// </param>
        /// <returns>
        /// True if an object exists at the specified path, false otherwise.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        private bool ItemExists(string path, out ErrorRecord error)
        {
            error = null;

            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            bool result = false;

            path = NormalizePath(path);

            try
            {
                var fsinfo = GetFileSystemInfo(path, out bool _);
                result = fsinfo != null;

                FileSystemItemProviderDynamicParameters itemExistsDynamicParameters =
                    DynamicParameters as FileSystemItemProviderDynamicParameters;

                // If the items see if we need to check the age of the file...
                if (result && itemExistsDynamicParameters != null)
                {
                    DateTime lastWriteTime = fsinfo.LastWriteTime;

                    if (itemExistsDynamicParameters.OlderThan.HasValue)
                    {
                        result &= lastWriteTime < itemExistsDynamicParameters.OlderThan.Value;
                    }

                    if (itemExistsDynamicParameters.NewerThan.HasValue)
                    {
                        result &= lastWriteTime > itemExistsDynamicParameters.NewerThan.Value;
                    }
                }
            }
            catch (System.Security.SecurityException security)
            {
                error = new ErrorRecord(security, "ItemExistsSecurityError", ErrorCategory.PermissionDenied, path);
            }
            catch (ArgumentException argument)
            {
                error = new ErrorRecord(argument, "ItemExistsArgumentError", ErrorCategory.InvalidArgument, path);
            }
            catch (UnauthorizedAccessException unauthorized)
            {
                error = new ErrorRecord(unauthorized, "ItemExistsUnauthorizedAccessError", ErrorCategory.PermissionDenied, path);
            }
            catch (PathTooLongException pathTooLong)
            {
                error = new ErrorRecord(pathTooLong, "ItemExistsPathTooLongError", ErrorCategory.InvalidArgument, path);
            }
            catch (NotSupportedException notSupported)
            {
                error = new ErrorRecord(notSupported, "ItemExistsNotSupportedError", ErrorCategory.InvalidOperation, path);
            }

            return result;
        }

        /// <summary>
        /// Adds -OlderThan, -NewerThan dynamic properties.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item to get the dynamic parameters for.
        /// </param>
        /// <returns>
        /// Overrides of this method should return an object that has properties and fields decorated with
        /// parsing attributes similar to a cmdlet class or a
        /// <see cref="System.Management.Automation.RuntimeDefinedParameterDictionary"/>.
        ///
        /// The default implementation returns null. (no additional parameters)
        /// </returns>
        protected override object ItemExistsDynamicParameters(string path)
        {
            using (PSTransactionManager.GetEngineProtectionScope())
            {
                return new FileSystemItemProviderDynamicParameters();
            }
        }

        #endregion ItemExists

        #region HasChildItems

        /// <summary>
        /// Determines if the given path is a directory, and has children.
        /// </summary>
        /// <param name="path">
        /// The full path to the directory.
        /// </param>
        /// <returns>
        /// True if the path refers to a directory that contains other
        /// directories or files.  False otherwise.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override bool HasChildItems(string path)
        {
            bool result = false;

            // verify parameters
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            // First check to see if it is a directory
            try
            {
                DirectoryInfo directory = new DirectoryInfo(path);

                // If the above didn't throw an exception, check to
                // see if we should proceed and if it contains any children
                if ((directory.Attributes & FileAttributes.Directory) != FileAttributes.Directory)
                    return false;

                result = DirectoryInfoHasChildItems(directory);
            }
            catch (ArgumentNullException)
            {
                // Since we couldn't convert the path to a DirectoryInfo
                // the path could not be a file system container with
                // children
                result = false;
            }
            catch (ArgumentException)
            {
                // Since we couldn't convert the path to a DirectoryInfo
                // the path could not be a file system container with
                // children
                result = false;
            }
            catch (UnauthorizedAccessException)
            {
                // Since we couldn't convert the path to a DirectoryInfo
                // the path could not be a file system container with
                // children
                result = false;
            }
            catch (IOException)
            {
                // Since we couldn't convert the path to a DirectoryInfo
                // the path could not be a file system container with
                // children
                result = false;
            }
            catch (NotSupportedException)
            {
                // Happens when we try to access an alternate data stream
                result = false;
            }

            return result;
        }

        private static bool DirectoryInfoHasChildItems(DirectoryInfo directory)
        {
            Dbg.Diagnostics.Assert(
                directory != null,
                "The caller should verify directory.");

            bool result = false;

            IEnumerable<FileSystemInfo> children = directory.EnumerateFileSystemInfos();

            if (children.Any())
            {
                result = true;
            }

            return result;
        }

        #endregion HasChildItems

        #region CopyItem

        /// <summary>
        /// Copies an item at the specified path to the given destination.
        /// </summary>
        /// <param name="path">
        /// The path of the item to copy.
        /// </param>
        /// <param name="destinationPath">
        /// The path of the destination.
        /// </param>
        /// <param name="recurse">
        /// Specifies if the operation should also copy child items.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        ///     destination path is null or empty.
        /// </exception>
        /// <returns>
        /// Nothing.  Copied items are written to the context's pipeline.
        /// </returns>
        protected override void CopyItem(
            string path,
            string destinationPath,
            bool recurse)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            if (string.IsNullOrEmpty(destinationPath))
            {
                throw PSTraceSource.NewArgumentException(nameof(destinationPath));
            }

            path = NormalizePath(path);
            destinationPath = NormalizePath(destinationPath);

            PSSession fromSession = null;
            PSSession toSession = null;

            CopyItemDynamicParameters copyDynamicParameter = DynamicParameters as CopyItemDynamicParameters;

            if (copyDynamicParameter != null)
            {
                if (copyDynamicParameter.FromSession != null)
                {
                    fromSession = copyDynamicParameter.FromSession;
                }
                else
                {
                    toSession = copyDynamicParameter.ToSession;
                }
            }

            _excludeMatcher = SessionStateUtilities.CreateWildcardsFromStrings(Exclude, WildcardOptions.IgnoreCase);

            // if the source and destination path are same (for a local copy) then flag it as error.
            if ((toSession == null) && (fromSession == null) && InternalSymbolicLinkLinkCodeMethods.IsSameFileSystemItem(path, destinationPath))
            {
                string error = StringUtil.Format(FileSystemProviderStrings.CopyError, path);
                Exception e = new IOException(error);
                e.Data[SelfCopyDataKey] = destinationPath;
                WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, path));
                return;
            }
            // Copy-Item from session
            if (fromSession != null)
            {
                CopyItemFromRemoteSession(path, destinationPath, recurse, Force, fromSession);
            }
            else
            {
                // Copy-Item to session
                if (toSession != null)
                {
                    using (System.Management.Automation.PowerShell ps = System.Management.Automation.PowerShell.Create())
                    {
                        ps.Runspace = toSession.Runspace;
                        CopyItemLocalOrToSession(path, destinationPath, recurse, Force, ps);
                    }
                }
                else // Copy-Item local
                {
                    if (Context != null && Context.ExecutionContext.SessionState.PSVariable.Get(SpecialVariables.ProgressPreferenceVarPath.UserPath).Value is ActionPreference progressPreference && progressPreference == ActionPreference.Continue)
                    {
                        {
                            Task.Run(() =>
                            {
                                GetTotalFiles(path, recurse);
                            });
                            _copyStopwatch.Start();
                        }
                    }

                    CopyItemLocalOrToSession(path, destinationPath, recurse, Force, null);
                    if (Stopping || _copiedFiles == _totalFiles)
                    {
                        _copyStopwatch.Stop();
                        var progress = new ProgressRecord(COPY_FILE_ACTIVITY_ID, " ", " ");
                        progress.RecordType = ProgressRecordType.Completed;
                        WriteProgress(progress);
                    }
                }
            }

            _excludeMatcher.Clear();
            _excludeMatcher = null;
        }

        private void GetTotalFiles(string path, bool recurse)
        {
            bool isContainer = IsItemContainer(path);

            try
            {
                if (isContainer)
                {
                    var enumOptions = new EnumerationOptions()
                    {
                        IgnoreInaccessible = true,
                        AttributesToSkip = 0,
                        RecurseSubdirectories = recurse
                    };

                    var directory = new DirectoryInfo(path);
                    foreach (var file in directory.EnumerateFiles("*", enumOptions))
                    {
                        if (!SessionStateUtilities.MatchesAnyWildcardPattern(file.Name, _excludeMatcher, defaultValue: false))
                        {
                            _totalFiles++;
                            _totalBytes += file.Length;
                        }
                    }
                }
                else
                {
                    var file = new FileInfo(path);
                    if (!SessionStateUtilities.MatchesAnyWildcardPattern(file.Name, _excludeMatcher, defaultValue: false))
                    {
                        _totalFiles++;
                        _totalBytes += file.Length;
                    }
                }
            }
            catch
            {
                // ignore exception
            }
        }

        private void CopyItemFromRemoteSession(string path, string destinationPath, bool recurse, bool force, PSSession fromSession)
        {
            using (System.Management.Automation.PowerShell ps = System.Management.Automation.PowerShell.Create())
            {
                ps.Runspace = fromSession.Runspace;

                InitializeFunctionPSCopyFileFromRemoteSession(ps);

                try
                {
                    // get info on source
                    ps.AddCommand(CopyFileRemoteUtils.PSCopyFromSessionHelperName);
                    ps.AddParameter("getPathItems", path);

                    Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);
                    if (op == null)
                    {
                        Exception e = new IOException(string.Format(CultureInfo.InvariantCulture, FileSystemProviderStrings.CopyItemRemotelyFailedToReadFile, path));
                        WriteError(new ErrorRecord(e, "CopyItemRemotelyFailedToReadFile", ErrorCategory.WriteError, path));
                        return;
                    }

                    bool exists = (bool)(op["Exists"]);
                    if (!exists)
                    {
                        throw PSTraceSource.NewArgumentNullException(SessionStateStrings.PathNotFound, path);
                    }

                    if (op["Items"] != null)
                    {
                        PSObject obj = (PSObject)op["Items"];
                        ArrayList itemsList = (ArrayList)obj.BaseObject;
                        foreach (PSObject item in itemsList)
                        {
                            Hashtable ItemInfo = (Hashtable)item.BaseObject;
                            string itemName = (string)ItemInfo["Name"];
                            string itemFullName = (string)ItemInfo["FullName"];
                            bool isContainer = (bool)ItemInfo["IsDirectory"];

                            if (isContainer)
                            {
                                if (File.Exists(destinationPath))
                                {
                                    Exception e = new IOException(string.Format(
                                        CultureInfo.InvariantCulture,
                                        FileSystemProviderStrings.CopyItemRemotelyDestinationIsFile,
                                        path,
                                        destinationPath));
                                    WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, destinationPath));
                                    return;
                                }

                                CopyDirectoryFromRemoteSession(
                                    itemName,
                                    itemFullName,
                                    destinationPath,
                                    force,
                                    recurse,
                                    ps);
                            }
                            else
                            {
                                bool excludeFile = SessionStateUtilities.MatchesAnyWildcardPattern(itemName, _excludeMatcher, false);
                                if (!excludeFile)
                                {
                                    long itemSize = (long)ItemInfo["FileSize"];
                                    CopyFileFromRemoteSession(itemName, itemFullName, destinationPath, force, ps, itemSize);
                                }
                            }
                        }
                    }
                }
                finally
                {
                    RemoveFunctionsPSCopyFileFromRemoteSession(ps);
                }
            }
        }

        private void CopyItemLocalOrToSession(string path, string destinationPath, bool recurse, bool Force, System.Management.Automation.PowerShell ps)
        {
            bool isContainer = IsItemContainer(path);

            InitializeFunctionsPSCopyFileToRemoteSession(ps);

            try
            {
                if (isContainer)
                {
                    // Get the directory info
                    DirectoryInfo dir = new DirectoryInfo(path);

                    // Now copy the directory to the destination
                    CopyDirectoryInfoItem(dir, destinationPath, recurse, Force, ps);
                }
                else // !isContainer
                {
                    // Get the file info
                    FileInfo file = new FileInfo(path);

                    CopyFileInfoItem(file, destinationPath, Force, ps);
                }
            }
            finally
            {
                RemoveFunctionPSCopyFileToRemoteSession(ps);
            }
        }

        private void CopyDirectoryInfoItem(
            DirectoryInfo directory,
            string destination,
            bool recurse,
            bool force,
            System.Management.Automation.PowerShell ps)
        {
            Dbg.Diagnostics.Assert(
                directory != null,
                "The caller should verify directory.");

            // Generate the path based on whether the destination path exists and
            // is a container.
            // If the destination exists and is a container the directory we are copying
            // will become a child of that directory.
            // If the destination doesn't exist we will just try to copy to that new
            // path.

            if (ps == null)
            {
                if (IsItemContainer(destination))
                {
                    destination = MakePath(destination, directory.Name);
                }
            }
            else
            {
                if (RemoteDirectoryExist(ps, destination))
                {
                    destination = Path.Combine(destination, directory.Name);
                }
            }

            s_tracer.WriteLine("destination = {0}", destination);

            // Confirm the copy with the user
            string action = FileSystemProviderStrings.CopyItemActionDirectory;

            string resource = StringUtil.Format(FileSystemProviderStrings.CopyItemResourceFileTemplate, directory.FullName, destination);

            if (ShouldProcess(resource, action))
            {
                // Create the new directory
                // CreateDirectory does the WriteItemObject for the new DirectoryInfo
                if (ps == null)
                {
                    CreateDirectory(destination, true);
                }
                else
                {
                    // Verify that the destination is not a file on the remote end
                    if (RemoteDestinationPathIsFile(destination, ps))
                    {
                        Exception e = new IOException(string.Format(CultureInfo.InvariantCulture,
                                                                    FileSystemProviderStrings.CopyItemRemoteDestinationIsFile,
                                                                    destination));
                        WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, destination));
                        return;
                    }

                    destination = CreateDirectoryOnRemoteSession(destination, force, ps);
                    if (destination == null)
                    {
                        return;
                    }
                }

                if (recurse)
                {
                    // Now copy all the files to that directory
                    IEnumerable<FileInfo> files = null;

                    if (string.IsNullOrEmpty(Filter))
                    {
                        files = directory.EnumerateFiles();
                    }
                    else
                    {
                        files = directory.EnumerateFiles(Filter);
                    }

                    foreach (FileInfo file in files)
                    {
                        // Making sure to obey the StopProcessing.
                        if (Stopping)
                        {
                            return;
                        }

                        if (file != null)
                        {
                            try
                            {
                                // CopyFileInfoItem does the WriteItemObject for the new FileInfo
                                CopyFileInfoItem(file, destination, force, ps);
                            }
                            catch (ArgumentException argException)
                            {
                                WriteError(new ErrorRecord(argException, "CopyDirectoryInfoItemArgumentError", ErrorCategory.InvalidArgument, file));
                            }
                            catch (IOException ioException)
                            {
                                // IOException contains specific message about the error occurred and so no need for errordetails.
                                WriteError(new ErrorRecord(ioException, "CopyDirectoryInfoItemIOError", ErrorCategory.WriteError, file));
                            }
                            catch (UnauthorizedAccessException accessException)
                            {
                                WriteError(new ErrorRecord(accessException, "CopyDirectoryInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, file));
                            }
                        }
                    }

                    // Now copy all the directories to that directory
                    foreach (DirectoryInfo childDir in directory.EnumerateDirectories())
                    {
                        // Making sure to obey the StopProcessing.
                        if (Stopping)
                        {
                            return;
                        }

                        if (childDir != null)
                        {
                            try
                            {
                                CopyDirectoryInfoItem(childDir, destination, recurse, force, ps);
                            }
                            catch (ArgumentException argException)
                            {
                                WriteError(new ErrorRecord(argException, "CopyDirectoryInfoItemArgumentError", ErrorCategory.InvalidArgument, childDir));
                            }
                            catch (IOException ioException)
                            {
                                // IOException contains specific message about the error occurred and so no need for errordetails.
                                WriteError(new ErrorRecord(ioException, "CopyDirectoryInfoItemIOError", ErrorCategory.WriteError, childDir));
                            }
                            catch (UnauthorizedAccessException accessException)
                            {
                                WriteError(new ErrorRecord(accessException, "CopyDirectoryInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, childDir));
                            }
                        }
                    }
                }
            }
        }

        private void CopyFileInfoItem(FileInfo file, string destinationPath, bool force, System.Management.Automation.PowerShell ps)
        {
            Dbg.Diagnostics.Assert(
                file != null,
                "The caller should verify file.");

            // If the destination is a container, add the file name
            // to the destination path.
            if (ps == null)
            {
                if (IsItemContainer(destinationPath))
                {
                    destinationPath = MakePath(destinationPath, file.Name);
                }

                // if the source and destination path are same then flag it as error.
                if (InternalSymbolicLinkLinkCodeMethods.IsSameFileSystemItem(destinationPath, file.FullName))
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.CopyError, destinationPath);
                    Exception e = new IOException(error);
                    e.Data[SelfCopyDataKey] = file.FullName;
                    WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, destinationPath));
                    return;
                }
                // Verify that the target doesn't represent a device name
                if (PathIsReservedDeviceName(destinationPath, "CopyError"))
                {
                    return;
                }
            }

            // Confirm the copy with the user
            string action = FileSystemProviderStrings.CopyItemActionFile;

            string resource = StringUtil.Format(FileSystemProviderStrings.CopyItemResourceFileTemplate, file.FullName, destinationPath);

            bool excludeFile = SessionStateUtilities.MatchesAnyWildcardPattern(file.Name, _excludeMatcher, defaultValue: false);

            if (!excludeFile)
            {
                if (ShouldProcess(resource, action))
                {
                    try
                    {
                        if (ps == null)
                        {
                            // Now copy the file
                            // We assume that if we get called we want to make
                            // the copy even if the destination already exists.
                            file.CopyTo(destinationPath, true);

                            FileInfo result = new FileInfo(destinationPath);
                            WriteItemObject(result, destinationPath, false);

                            if (_totalFiles > 0)
                            {
                                _copiedFiles++;
                                _copiedBytes += file.Length;
                                if (_copyStopwatch.Elapsed.TotalSeconds > ProgressBarDurationThreshold)
                                {
                                    double speed = (double)(_copiedBytes / 1024 / 1024) / _copyStopwatch.Elapsed.TotalSeconds;
                                    var progress = new ProgressRecord(
                                        COPY_FILE_ACTIVITY_ID,
                                        StringUtil.Format(FileSystemProviderStrings.CopyingLocalFileActivity, _copiedFiles, _totalFiles),
                                        StringUtil.Format(FileSystemProviderStrings.CopyingLocalBytesStatus, Utils.DisplayHumanReadableFileSize(_copiedBytes), Utils.DisplayHumanReadableFileSize(_totalBytes), speed)
                                    );
                                    var percentComplete = _totalBytes != 0 ? (int)Math.Min(_copiedBytes * 100 / _totalBytes, 100) : 100;
                                    progress.PercentComplete = percentComplete;
                                    progress.RecordType = ProgressRecordType.Processing;
                                    WriteProgress(progress);
                                }
                            }
                        }
                        else
                        {
                            PerformCopyFileToRemoteSession(file, destinationPath, ps);
                        }
                    }
                    catch (System.UnauthorizedAccessException unAuthorizedAccessException)
                    {
                        if (force)
                        {
                            try
                            {
                                if (ps == null)
                                {
                                    // If the destination exists and force is specified,
                                    // mask of the readonly and hidden attributes and
                                    // try again
                                    FileInfo destinationItem = new FileInfo(destinationPath);

                                    destinationItem.Attributes &= ~(FileAttributes.ReadOnly | FileAttributes.Hidden);
                                }
                                else
                                {
                                    PerformCopyFileToRemoteSession(file, destinationPath, ps);
                                }
                            }
                            catch (Exception exception)
                            {
                                if ((exception is FileNotFoundException) ||
                                    (exception is DirectoryNotFoundException) ||
                                    (exception is System.Security.SecurityException) ||
                                    (exception is ArgumentException) ||
                                    (exception is IOException))
                                {
                                    // Write out the original error since we failed to force the copy
                                    WriteError(new ErrorRecord(unAuthorizedAccessException, "CopyFileInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, file));
                                }
                                else
                                {
                                    throw;
                                }
                            }

                            file.CopyTo(destinationPath, true);

                            FileInfo result = new FileInfo(destinationPath);
                            WriteItemObject(result, destinationPath, false);
                        }
                        else
                        {
                            WriteError(new ErrorRecord(unAuthorizedAccessException, "CopyFileInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, file));
                        }
                    }
                    catch (IOException ioException)
                    {
                        WriteError(new ErrorRecord(ioException, "CopyFileInfoItemIOError", ErrorCategory.WriteError, file));
                    }
                }
            }
        }

        private void CopyDirectoryFromRemoteSession(
            string sourceDirectoryName,
            string sourceDirectoryFullName,
            string destination,
            bool force,
            bool recurse,
            System.Management.Automation.PowerShell ps)
        {
            Dbg.Diagnostics.Assert((sourceDirectoryName != null && sourceDirectoryFullName != null), "The caller should verify directory.");

            if (IsItemContainer(destination))
            {
                destination = MakePath(destination, sourceDirectoryName);
            }

            s_tracer.WriteLine("destination = {0}", destination);

            // Confirm the copy with the user
            string action = FileSystemProviderStrings.CopyItemActionDirectory;
            string resource = StringUtil.Format(FileSystemProviderStrings.CopyItemResourceFileTemplate, sourceDirectoryFullName, destination);

            if (ShouldProcess(resource, action))
            {
                // Create destinationPath directory. This will fail if the directory already exists
                // and Force is not selected.
                CreateDirectory(destination, false);

                // If failed to create directory
                if (!Directory.Exists(destination))
                {
                    return;
                }

                if (recurse)
                {
                    // Get all the files for that directory from the remote session
                    ps.AddCommand(CopyFileRemoteUtils.PSCopyFromSessionHelperName);
                    ps.AddParameter("getPathDir", sourceDirectoryFullName);

                    Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);
                    if (op == null)
                    {
                        Exception e = new IOException(string.Format(
                                                      CultureInfo.InvariantCulture,
                                                      FileSystemProviderStrings.CopyItemRemotelyFailedToGetDirectoryChildItems,
                                                      sourceDirectoryFullName));
                        WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, sourceDirectoryFullName));
                        return;
                    }

                    if (op["Files"] != null)
                    {
                        PSObject obj = (PSObject)op["Files"];
                        ArrayList filesList = (ArrayList)obj.BaseObject;

                        foreach (PSObject fileObject in filesList)
                        {
                            Hashtable file = (Hashtable)fileObject.BaseObject;
                            string fileName = (string)file["FileName"];
                            string filePath = (string)file["FilePath"];
                            long fileSize = (long)file["FileSize"];

                            // Making sure to obey the StopProcessing.
                            if (Stopping)
                            {
                                return;
                            }

                            bool excludeFile = SessionStateUtilities.MatchesAnyWildcardPattern(fileName, _excludeMatcher, defaultValue: false);

                            if (!excludeFile)
                            {
                                // If an exception is thrown in the remote session, it is surface to the user via PowerShell Write-Error.
                                CopyFileFromRemoteSession(fileName,
                                                          filePath,
                                                          destination,
                                                          force,
                                                          ps,
                                                          fileSize);
                            }
                        }
                    }

                    if (op["Directories"] != null)
                    {
                        PSObject obj = (PSObject)op["Directories"];
                        ArrayList directories = (ArrayList)obj.BaseObject;

                        foreach (PSObject dirObject in directories)
                        {
                            Hashtable dir = (Hashtable)dirObject.BaseObject;
                            string dirName = (string)dir["Name"];
                            string dirFullName = (string)dir["FullName"];

                            // Making sure to obey the StopProcessing.
                            if (Stopping)
                            {
                                return;
                            }

                            // If an exception is thrown in the remote session, it is surface to the user via PowerShell Write-Error.
                            CopyDirectoryFromRemoteSession(dirName,
                                                           dirFullName,
                                                           destination,
                                                           force,
                                                           recurse,
                                                           ps);
                        }
                    }
                }
            }
        }

        private ArrayList GetRemoteSourceAlternateStreams(System.Management.Automation.PowerShell ps, string path)
        {
            ArrayList streams = null;
            bool supportsAlternateStreams = false;

            ps.AddCommand(CopyFileRemoteUtils.PSCopyFromSessionHelperName);
            ps.AddParameter("supportAltStreamPath", path);

            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);
            if (op != null && op["SourceSupportsAlternateStreams"] != null)
            {
                supportsAlternateStreams = (bool)op["SourceSupportsAlternateStreams"];
            }

            if (supportsAlternateStreams)
            {
                PSObject obj = (PSObject)op["Streams"];
                streams = (ArrayList)obj.BaseObject;
            }

            return streams;
        }

        private void InitializeFunctionPSCopyFileFromRemoteSession(System.Management.Automation.PowerShell ps)
        {
            if ((ps == null) || !ValidRemoteSessionForScripting(ps.Runspace))
            {
                return;
            }

            ps.AddScript(CopyFileRemoteUtils.AllCopyFromRemoteScripts);
            SafeInvokeCommand.Invoke(ps, this, null, false);
        }

        private void RemoveFunctionsPSCopyFileFromRemoteSession(System.Management.Automation.PowerShell ps)
        {
            if ((ps == null) || !ValidRemoteSessionForScripting(ps.Runspace))
            {
                return;
            }

            const string remoteScript = @"
                Microsoft.PowerShell.Management\Remove-Item function:PSCopyFromSessionHelper -ea SilentlyContinue -Force
                Microsoft.PowerShell.Management\Remove-Item function:PSCopyRemoteUtils -ea SilentlyContinue -Force
            ";
            ps.AddScript(remoteScript);
            SafeInvokeCommand.Invoke(ps, this, null, false);
        }

        private static bool ValidRemoteSessionForScripting(Runspace runspace)
        {
            if (runspace is not RemoteRunspace)
            {
                return false;
            }

            PSLanguageMode languageMode = runspace.SessionStateProxy.LanguageMode;
            if (languageMode == PSLanguageMode.ConstrainedLanguage || languageMode == PSLanguageMode.NoLanguage)
            {
                // SessionStateInternal.ValidateRemotePathAndGetRoot checked for expected helper functions on the
                // restricted session and will have returned an error if they are missing.  So at this point we
                // assume the session is set up with the needed helper functions.
                return false;
            }

            return true;
        }

        private Hashtable GetRemoteFileMetadata(string filePath, System.Management.Automation.PowerShell ps)
        {
            ps.AddCommand(CopyFileRemoteUtils.PSCopyFromSessionHelperName);
            ps.AddParameter("getMetaFilePath", filePath);
            Hashtable metadata = SafeInvokeCommand.Invoke(ps, this, null);
            return metadata;
        }

        private void SetFileMetadata(string sourceFileFullName, FileInfo destinationFile, System.Management.Automation.PowerShell ps)
        {
            Hashtable metadata = GetRemoteFileMetadata(sourceFileFullName, ps);

            if (metadata != null)
            {
                // LastWriteTime
                if (metadata["LastWriteTimeUtc"] != null)
                {
                    destinationFile.LastWriteTimeUtc = (DateTime)metadata["LastWriteTimeUtc"];
                }

                if (metadata["LastWriteTime"] != null)
                {
                    destinationFile.LastWriteTime = (DateTime)metadata["LastWriteTime"];
                }

                // Attributes
                if (metadata["Attributes"] != null)
                {
                    PSObject obj = (PSObject)metadata["Attributes"];
                    foreach (string value in (ArrayList)obj.BaseObject)
                    {
                        if (string.Equals(value, "ReadOnly", StringComparison.OrdinalIgnoreCase))
                        {
                            destinationFile.Attributes |= FileAttributes.ReadOnly;
                        }
                        else if (string.Equals(value, "Hidden", StringComparison.OrdinalIgnoreCase))
                        {
                            destinationFile.Attributes |= FileAttributes.Hidden;
                        }
                        else if (string.Equals(value, "Archive", StringComparison.OrdinalIgnoreCase))
                        {
                            destinationFile.Attributes |= FileAttributes.Archive;
                        }
                        else if (string.Equals(value, "System", StringComparison.OrdinalIgnoreCase))
                        {
                            destinationFile.Attributes |= FileAttributes.System;
                        }
                    }
                }
            }
        }

        private void CopyFileFromRemoteSession(
            string sourceFileName,
            string sourceFileFullName,
            string destinationPath,
            bool force,
            System.Management.Automation.PowerShell ps,
            long fileSize = 0)
        {
            Dbg.Diagnostics.Assert(sourceFileFullName != null, "The caller should verify file.");

            // If the destination is a container, add the file name
            // to the destination path.
            if (IsItemContainer(destinationPath))
            {
                destinationPath = MakePath(destinationPath, sourceFileName);
            }

            // Verify that the target doesn't represent a device name
            if (PathIsReservedDeviceName(destinationPath, "CopyError"))
            {
                return;
            }

            FileInfo destinationFile = new FileInfo(destinationPath);

            string action = FileSystemProviderStrings.CopyItemActionFile;
            string resource = StringUtil.Format(FileSystemProviderStrings.CopyItemResourceFileTemplate, sourceFileFullName, destinationPath);

            if (ShouldProcess(resource, action))
            {
                bool result = PerformCopyFileFromRemoteSession(sourceFileFullName, destinationFile, destinationPath, force, ps, fileSize, false, null);

                // Copying the file from the remote session completed successfully
                if (result)
                {
                    // Check if the remote source file has any alternate data streams
                    ArrayList remoteFileStreams = GetRemoteSourceAlternateStreams(ps, sourceFileFullName);
                    if ((remoteFileStreams != null) && (remoteFileStreams.Count > 0))
                    {
                        foreach (string streamName in remoteFileStreams)
                        {
                            result = PerformCopyFileFromRemoteSession(sourceFileFullName, destinationFile, destinationPath, force, ps, fileSize, true, streamName);
                            if (!result)
                            {
                                break;
                            }
                        }
                    }
                }

                // The file was copied successfully. Now, set the file metadata
                if (result)
                {
                    SetFileMetadata(sourceFileFullName, destinationFile, ps);
                }
            }
        }

        private bool PerformCopyFileFromRemoteSession(string sourceFileFullName, FileInfo destinationFile, string destinationPath, bool force, System.Management.Automation.PowerShell ps,
                                                      long fileSize, bool isAlternateDataStream, string streamName)
        {
            bool success = false;
            string activity = string.Format(CultureInfo.InvariantCulture,
                                            FileSystemProviderStrings.CopyItemRemotelyProgressActivity,
                                            sourceFileFullName,
                                            destinationFile.FullName);
            string statusDescription = string.Format(CultureInfo.InvariantCulture,
                                                        FileSystemProviderStrings.CopyItemRemotelyStatusDescription,
                                                        ps.Runspace.ConnectionInfo.ComputerName,
                                                        "localhost");

            ProgressRecord progress = new ProgressRecord(0, activity, statusDescription);
            progress.PercentComplete = 0;
            progress.RecordType = ProgressRecordType.Processing;
            WriteProgress(progress);
            FileStream wStream = null;
            bool errorWhileCopyRemoteFile = false;

            try
            {
                // The main data stream
                if (!isAlternateDataStream)
                {
                    // If force is specified, and the file already exist at the destination, mask of the readonly, hidden, and system attributes
                    if (force && File.Exists(destinationFile.FullName))
                    {
                        destinationFile.Attributes &= ~(FileAttributes.ReadOnly | FileAttributes.Hidden | FileAttributes.System);
                    }

                    wStream = new FileStream(destinationFile.FullName, FileMode.Create);
                }

#if !UNIX
                // an alternate stream
                else
                {
                    wStream = AlternateDataStreamUtilities.CreateFileStream(destinationFile.FullName, streamName, FileMode.Append, FileAccess.Write, FileShare.ReadWrite);
                }
#endif
                const long fragmentSize = FILETRANSFERSIZE;
                long copiedSoFar = 0;
                long currentIndex = 0;

                while (true)
                {
                    ps.AddCommand(CopyFileRemoteUtils.PSCopyFromSessionHelperName);
                    ps.AddParameter("copyFromFilePath", sourceFileFullName);
                    ps.AddParameter("copyFromStart", currentIndex);
                    ps.AddParameter("copyFromNumBytes", fragmentSize);
                    if (force)
                    {
                        ps.AddParameter(nameof(force), true);
                    }

#if !UNIX
                    if (isAlternateDataStream)
                    {
                        ps.AddParameter("isAlternateStream", true);
                        ps.AddParameter(nameof(streamName), streamName);
                    }
#endif

                    Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);

                    // Check if there was an exception when reading the remote file.
                    if (op == null)
                    {
                        errorWhileCopyRemoteFile = true;
                        Exception e = new IOException(string.Format(CultureInfo.InvariantCulture,
                                                                    FileSystemProviderStrings.CopyItemRemotelyFailedToReadFile,
                                                                    sourceFileFullName));
                        WriteError(new ErrorRecord(e, "FailedToCopyFileFromRemoteSession", ErrorCategory.WriteError, sourceFileFullName));
                        break;
                    }

                    if (op["ExceptionThrown"] != null)
                    {
                        bool failedToReadFile = (bool)(op["ExceptionThrown"]);
                        if (failedToReadFile)
                        {
                            // The error is written to the error array via SafeInvokeCommand
                            errorWhileCopyRemoteFile = true;
                            break;
                        }
                    }

                    // To accommodate empty files
                    string content = string.Empty;
                    if (op["b64Fragment"] != null)
                    {
                        content = (string)op["b64Fragment"];
                    }

                    bool more = (bool)op["moreAvailable"];
                    currentIndex += fragmentSize;
                    byte[] bytes = System.Convert.FromBase64String(content);
                    wStream.Write(bytes, 0, bytes.Length);
                    copiedSoFar += bytes.Length;

                    if (wStream.Length > 0)
                    {
                        int percentage = (int)(copiedSoFar * 100 / wStream.Length);
                        progress.PercentComplete = percentage;
                        WriteProgress(progress);
                    }

                    if (!more)
                    {
                        success = true;
                        break;
                    }
                }

                progress.PercentComplete = 100;
                progress.RecordType = ProgressRecordType.Completed;
                WriteProgress(progress);
            }
            catch (IOException ioException)
            {
                // IOException takes care of FileNotFoundException, DirectoryNotFoundException, and PathTooLongException
                WriteError(new ErrorRecord(ioException, "CopyItemRemotelyIOError", ErrorCategory.WriteError, sourceFileFullName));
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "CopyItemRemotelyArgumentError", ErrorCategory.WriteError, sourceFileFullName));
            }
            catch (NotSupportedException notSupportedException)
            {
                WriteError(new ErrorRecord(notSupportedException, "CopyFileInfoRemotelyPathRefersToANonFileDevice", ErrorCategory.InvalidArgument, sourceFileFullName));
            }
            catch (SecurityException securityException)
            {
                WriteError(new ErrorRecord(securityException, "CopyFileInfoRemotelyUnauthorizedAccessError", ErrorCategory.PermissionDenied, sourceFileFullName));
            }
            catch (UnauthorizedAccessException unauthorizedAccessException)
            {
                WriteError(new ErrorRecord(unauthorizedAccessException, "CopyFileInfoItemRemotelyUnauthorizedAccessError", ErrorCategory.PermissionDenied, sourceFileFullName));
            }
            finally
            {
                wStream?.Dispose();

                // If copying the file from the remote session failed, then remove it.
                if (errorWhileCopyRemoteFile && File.Exists(destinationFile.FullName))
                {
                    if (!(destinationFile.Attributes.HasFlag(FileAttributes.ReadOnly) ||
                            destinationFile.Attributes.HasFlag(FileAttributes.Hidden) ||
                            destinationFile.Attributes.HasFlag(FileAttributes.System)))
                    {
                        RemoveFileSystemItem(destinationFile, true);
                    }
                }
            }

            return success;
        }

        private void InitializeFunctionsPSCopyFileToRemoteSession(System.Management.Automation.PowerShell ps)
        {
            if ((ps == null) || !ValidRemoteSessionForScripting(ps.Runspace))
            {
                return;
            }

            ps.AddScript(CopyFileRemoteUtils.AllCopyToRemoteScripts);
            SafeInvokeCommand.Invoke(ps, this, null, false);
        }

        private void RemoveFunctionPSCopyFileToRemoteSession(System.Management.Automation.PowerShell ps)
        {
            if ((ps == null) || !ValidRemoteSessionForScripting(ps.Runspace))
            {
                return;
            }

            const string remoteScript = @"
                Microsoft.PowerShell.Management\Remove-Item function:PSCopyToSessionHelper -ea SilentlyContinue -Force
                Microsoft.PowerShell.Management\Remove-Item function:PSCopyRemoteUtils -ea SilentlyContinue -Force
            ";
            ps.AddScript(remoteScript);
            SafeInvokeCommand.Invoke(ps, this, null, false);
        }

        // If the target supports alternate data streams the following must be true:
        // 1) The remote session must be PowerShell V3 or higher to support Streams
        // 2) The target drive must be NTFS
        private bool RemoteTargetSupportsAlternateStreams(System.Management.Automation.PowerShell ps, string path)
        {
            bool supportsAlternateStreams = false;

            ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
            ps.AddParameter("supportAltStreamPath", path);

            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);
            if (op != null && op["TargetSupportsAlternateStreams"] != null)
            {
                supportsAlternateStreams = (bool)op["TargetSupportsAlternateStreams"];
            }

            return supportsAlternateStreams;
        }

        // Validate that the given remotePath exists, and do the following:
        // 1) If the remotePath is a FileInfo, then just return the remotePath.
        // 2) If the remotePath is a DirectoryInfo, then return the remotePath + the given filename.
        // 3) If the remote path does not exist, but its parent does, and it is a DirectoryInfo, then return the remotePath.
        // 4) If the remotePath or its parent do not exist, return null.
        private string MakeRemotePath(System.Management.Automation.PowerShell ps, string remotePath, string filename)
        {
            bool isFileInfo = false;
            bool isDirectoryInfo = false;
            bool parentIsDirectoryInfo = false;
            string path = null;

            ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
            ps.AddParameter(nameof(remotePath), remotePath);
            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);

            if (op != null)
            {
                if (op["IsDirectoryInfo"] != null)
                {
                    isDirectoryInfo = (bool)op["IsDirectoryInfo"];
                }

                if (op["IsFileInfo"] != null)
                {
                    isFileInfo = (bool)op["IsFileInfo"];
                }

                if (op["ParentIsDirectoryInfo"] != null)
                {
                    parentIsDirectoryInfo = (bool)op["ParentIsDirectoryInfo"];
                }
            }

            if (isFileInfo)
            {
                // The destination is a file, so we are going to overwrite it.
                path = remotePath;
            }
            else if (isDirectoryInfo)
            {
                // The destination is a directory, so append the file name to the path.
                path = Path.Combine(remotePath, filename);
            }
            else if (parentIsDirectoryInfo)
            {
                // At this point we know that the remotePath is neither a file or a directory on the remote target.
                // However, if the parent of the remotePath exists, then we are doing a copy-item operation in which
                // the destination file name is already being passed, e.g.,
                // copy-item -path c:\localDir\foo.txt -destination d:\remoteDir\bar.txt -toSession $s
                // Note that d:\remoteDir is a directory that exists on the remote target machine.
                path = remotePath;
            }

            return path;
        }

        private bool RemoteDirectoryExist(System.Management.Automation.PowerShell ps, string path)
        {
            bool pathExists = false;

            ps.AddCommand(CopyFileRemoteUtils.PSCopyRemoteUtilsName);
            ps.AddParameter("dirPathExists", path);
            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);

            if (op != null)
            {
                if (op["Exists"] != null)
                    pathExists = (bool)op["Exists"];
            }

            return pathExists;
        }

        private bool CopyFileStreamToRemoteSession(FileInfo file, string destinationPath, System.Management.Automation.PowerShell ps, bool isAlternateStream, string streamName)
        {
            string activity = string.Format(CultureInfo.InvariantCulture,
                                            FileSystemProviderStrings.CopyItemRemotelyProgressActivity,
                                            file.FullName,
                                            destinationPath);
            string statusDescription = string.Format(CultureInfo.InvariantCulture,
                                                     FileSystemProviderStrings.CopyItemRemotelyStatusDescription,
                                                     "localhost",
                                                     ps.Runspace.ConnectionInfo.ComputerName);

            ProgressRecord progress = new ProgressRecord(0, activity, statusDescription);
            progress.PercentComplete = 0;
            progress.RecordType = ProgressRecordType.Processing;
            WriteProgress(progress);

            // 4MB gives the best results without spiking the resources on the remote connection.
            const int fragmentSize = FILETRANSFERSIZE;
            byte[] fragment = null;
            int iteration = 0;
            bool success = false;

            FileStream fStream = null;
            try
            {
                // Main data stream
                if (!isAlternateStream)
                {
                    fStream = File.OpenRead(file.FullName);
                }
#if !UNIX
                else
                {
                    fStream = AlternateDataStreamUtilities.CreateFileStream(file.FullName, streamName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
                }
#endif
                long remainingFileSize = fStream != null ? fStream.Length : 0;
                do
                {
                    if (Stopping)
                    {
                        return false;
                    }

                    iteration++;
                    int toRead = fragmentSize;
                    if (toRead > remainingFileSize)
                    {
                        toRead = (int)remainingFileSize;
                    }

                    if (fragment == null)
                    {
                        fragment = new byte[toRead];
                    }
                    else if (toRead < fragmentSize)
                    {
                        fragment = new byte[toRead];
                    }

                    int readSoFar = 0;
                    while (readSoFar < toRead)
                    {
                        readSoFar += fStream.Read(fragment, 0, toRead);
                    }

                    remainingFileSize -= readSoFar;

                    string b64Fragment = System.Convert.ToBase64String(fragment);

                    // Main data stream
                    if (!isAlternateStream)
                    {
                        ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
                        ps.AddParameter("copyToFilePath", destinationPath);
                        ps.AddParameter("createFile", (iteration == 1));

                        if ((iteration == 1) && (b64Fragment.Length == 0))
                        {
                            // This fixes the case in which the user tries to copy an empty file between sessions.
                            // Scenario 1: The user creates an empty file using the Out-File cmdlet.
                            //             In this case the file length is 6.
                            //             "" | out-file test.txt
                            // Scenario 2: The user generates an empty file using the New-Item cmdlet.
                            //             In this case the file length is 0.
                            //             New-Item -Path test.txt -Type File
                            // Because of this, when we create the file on the remote session, we need to check
                            // the length of b64Fragment to figure out if we are creating an empty file.
                            ps.AddParameter("emptyFile", true);
                        }
                        else
                        {
                            ps.AddParameter("b64Fragment", b64Fragment);
                        }
                    }
                    else
                    {
                        ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
                        ps.AddParameter("copyToFilePath", destinationPath);
                        ps.AddParameter("b64Fragment", b64Fragment);
                        ps.AddParameter(nameof(streamName), streamName);
                    }

                    Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);
                    if (op == null || op["BytesWritten"] == null)
                    {
                        // write error to stream
                        Exception e = new IOException(string.Format(CultureInfo.InvariantCulture, FileSystemProviderStrings.CopyItemRemotelyFailed, file));
                        WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, file.FullName));
                        return false;
                    }

                    if ((int)(op["BytesWritten"]) != toRead)
                    {
                        Exception e = new IOException(string.Format(CultureInfo.InvariantCulture, FileSystemProviderStrings.CopyItemRemotelyFailed, file));
                        WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, file.FullName));
                        return false;
                    }

                    if (fStream.Length > 0)
                    {
                        int percentage = (int)((fStream.Length - remainingFileSize) * 100 / fStream.Length);
                        progress.PercentComplete = percentage;
                        WriteProgress(progress);
                    }
                } while (remainingFileSize > 0);
                progress.PercentComplete = 100;
                progress.RecordType = ProgressRecordType.Completed;
                WriteProgress(progress);
                success = true;
            }
            catch (IOException ioException)
            {
                // IOException takes care of FileNotFoundException, DirectoryNotFoundException, and PathTooLongException
                WriteError(new ErrorRecord(ioException, "CopyItemRemotelyIOError", ErrorCategory.WriteError, file.FullName));
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "CopyItemRemotelyArgumentError", ErrorCategory.WriteError, file.FullName));
            }
            catch (NotSupportedException notSupportedException)
            {
                WriteError(new ErrorRecord(notSupportedException, "CopyFileInfoRemotelyPathRefersToANonFileDevice", ErrorCategory.InvalidArgument, file.FullName));
            }
            catch (SecurityException securityException)
            {
                WriteError(new ErrorRecord(securityException, "CopyFileInfoRemotelyUnauthorizedAccessError", ErrorCategory.PermissionDenied, file.FullName));
            }
            finally
            {
                fStream?.Dispose();
            }

            return success;
        }

        // Returns a hash table with metadata about this file info.
        //
        private static Hashtable GetFileMetadata(FileInfo file)
        {
            Hashtable metadata = new Hashtable();

            // LastWriteTime
            metadata.Add("LastWriteTime", file.LastWriteTime);
            metadata.Add("LastWriteTimeUtc", file.LastWriteTimeUtc);

            // File attributes
            metadata.Add("Attributes", file.Attributes);

            return metadata;
        }

        private void SetRemoteFileMetadata(FileInfo file, string remoteFilePath, System.Management.Automation.PowerShell ps)
        {
            Hashtable metadata = GetFileMetadata(file);
            if (metadata != null)
            {
                ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
                ps.AddParameter("metaDataFilePath", remoteFilePath);
                ps.AddParameter("metaDataToSet", metadata);
                SafeInvokeCommand.Invoke(ps, this, null, false);
            }
        }

        private bool PerformCopyFileToRemoteSession(FileInfo file, string destinationPath, System.Management.Automation.PowerShell ps)
        {
            // Make the remote path
            var remoteFilePath = MakeRemotePath(ps, destinationPath, file.Name);

            if (string.IsNullOrEmpty(remoteFilePath))
            {
                Exception e = new ArgumentException(string.Format(CultureInfo.InvariantCulture, SessionStateStrings.PathNotFound, destinationPath));
                WriteError(new ErrorRecord(e, "RemotePathNotFound", ErrorCategory.WriteError, destinationPath));
                return false;
            }

            bool result = CopyFileStreamToRemoteSession(file, remoteFilePath, ps, false, null);

#if !UNIX
            bool targetSupportsAlternateStreams = RemoteTargetSupportsAlternateStreams(ps, remoteFilePath);

            // Once the file is copied successfully, check if the file has any alternate data streams
            if (result && targetSupportsAlternateStreams)
            {
                foreach (AlternateStreamData stream in AlternateDataStreamUtilities.GetStreams(file.FullName))
                {
                    if (!(string.Equals(":$DATA", stream.Stream, StringComparison.OrdinalIgnoreCase)))
                    {
                        result = CopyFileStreamToRemoteSession(file, remoteFilePath, ps, true, stream.Stream);
                        if (!result)
                        {
                            break;
                        }
                    }
                }
            }
#endif
            if (result)
            {
                SetRemoteFileMetadata(file, Path.Combine(destinationPath, file.Name), ps);
            }

            return result;
        }

        private bool RemoteDestinationPathIsFile(string destination, System.Management.Automation.PowerShell ps)
        {
            ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
            ps.AddParameter("isFilePath", destination);

            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);

            if (op == null || op["IsFileInfo"] == null)
            {
                Exception e = new IOException(string.Format(
                                                    CultureInfo.InvariantCulture,
                                                    FileSystemProviderStrings.CopyItemRemotelyFailedToValidateIfDestinationIsFile,
                                                    destination));
                WriteError(new ErrorRecord(e, "CopyError", ErrorCategory.WriteError, destination));
                return false;
            }

            return (bool)(op["IsFileInfo"]);
        }

        private string CreateDirectoryOnRemoteSession(string destination, bool force, System.Management.Automation.PowerShell ps)
        {
            ps.AddCommand(CopyFileRemoteUtils.PSCopyToSessionHelperName);
            ps.AddParameter("createDirectoryPath", destination);
            if (force)
            {
                ps.AddParameter(nameof(force), true);
            }

            Hashtable op = SafeInvokeCommand.Invoke(ps, this, null);

            // If op == null,  SafeInvokeCommand.Invoke throwns an error.
            if (op["ExceptionThrown"] != null)
            {
                // If an error is thrown on the remote session, it is written via SafeInvokeCommand.Invoke.
                if ((bool)op["ExceptionThrown"])
                    return null;
            }

            if (force && (op["DirectoryPath"] == null))
            {
                Exception e = new IOException(string.Format(CultureInfo.InvariantCulture,
                                                            FileSystemProviderStrings.CopyItemRemotelyFailedToCreateDirectory,
                                                            destination));
                WriteError(new ErrorRecord(e, "FailedToCreateDirectory", ErrorCategory.WriteError, destination));
                return null;
            }

            string path = (string)(op["DirectoryPath"]);

            if ((!force) && (bool)op["PathExists"])
            {
                Exception e = new IOException(StringUtil.Format(FileSystemProviderStrings.DirectoryExist, path));
                WriteError(new ErrorRecord(e, "DirectoryExist", ErrorCategory.ResourceExists, path));
                return null;
            }

            return path;
        }

        // Returns true if the destination path represents a device name, and write an error to the user.
        private bool PathIsReservedDeviceName(string destinationPath, string errorId)
        {
            bool pathIsReservedDeviceName = false;
            if (Utils.IsReservedDeviceName(destinationPath))
            {
                pathIsReservedDeviceName = true;
                string error = StringUtil.Format(FileSystemProviderStrings.TargetCannotContainDeviceName, destinationPath);
                Exception e = new IOException(error);
                WriteError(new ErrorRecord(e, errorId, ErrorCategory.WriteError, destinationPath));
            }

            return pathIsReservedDeviceName;
        }

        private long _totalFiles;
        private long _totalBytes;
        private long _copiedFiles;
        private long _copiedBytes;
        private readonly Stopwatch _copyStopwatch = new Stopwatch();

        private long _removedBytes;
        private long _removedFiles;
        private readonly Stopwatch _removeStopwatch = new();

        private const double ProgressBarDurationThreshold = 2.0;
        #endregion CopyItem

        #endregion ContainerCmdletProvider members

        #region NavigationCmdletProvider members

        /// <summary>
        /// Gets the parent of the given path.
        /// </summary>
        /// <param name="path">
        /// The path of which to get the parent.
        /// </param>
        /// <param name="root">
        /// The root of the drive.
        /// </param>
        /// <returns>
        /// The parent of the given path.
        /// </returns>
        protected override string GetParentPath(string path, string root)
        {
            string parentPath = base.GetParentPath(path, root);
            if (!Utils.PathIsUnc(path))
            {
                parentPath = EnsureDriveIsRooted(parentPath);
            }
#if !UNIX
            else if (parentPath.Equals(StringLiterals.DefaultPathSeparatorString, StringComparison.Ordinal))
            {
                // make sure we return two backslashes so it still results in a UNC path
                parentPath = "\\\\";
            }

            if (!parentPath.EndsWith(StringLiterals.DefaultPathSeparator)
                && Utils.PathIsDevicePath(parentPath)
                && parentPath.Length - parentPath.Replace(StringLiterals.DefaultPathSeparatorString, string.Empty).Length == 3)
            {
                // Device paths start with either "\\.\" or "\\?\"
                // When referring to the root, like: "\\.\CDROM0\" then it needs the trailing separator to be valid.
                parentPath += StringLiterals.DefaultPathSeparator;
            }
#endif
            s_tracer.WriteLine("GetParentPath returning '{0}'", parentPath);
            return parentPath;
        }

        // Note: we don't use IO.Path.IsPathRooted as this deals with "invalid" i.e. unnormalized paths
        private static bool IsAbsolutePath(string path)
        {
            // check if we're on a single root filesystem and it's an absolute path
            if (LocationGlobber.IsSingleFileSystemAbsolutePath(path))
            {
                return true;
            }

            return path.Contains(':');
        }

        /// <summary>
        /// Determines if the specified path is a root of a UNC share
        /// by counting the path separators "\" following "\\". If only
        /// one path separator is found we know the path is in the form
        /// "\\server\share" and is a valid UNC root.
        /// </summary>
        /// <param name="path">
        /// The path to check to see if its a UNC root.
        /// </param>
        /// <returns>
        /// True if the path is a UNC root, or false otherwise.
        /// </returns>
        private static bool IsUNCRoot(string path)
        {
            bool result = false;

            if (!string.IsNullOrEmpty(path))
            {
                if (Utils.PathIsUnc(path))
                {
                    int lastIndex = path.Length - 1;

                    if (path[path.Length - 1] == '\\')
                    {
                        lastIndex--;
                    }

                    int separatorsFound = 0;
                    do
                    {
                        lastIndex = path.LastIndexOf('\\', lastIndex);
                        if (lastIndex == -1)
                        {
                            break;
                        }

                        --lastIndex;
                        if (lastIndex < 3)
                        {
                            break;
                        }

                        ++separatorsFound;
                    } while (lastIndex > 3);

                    if (separatorsFound == 1)
                    {
                        result = true;
                    }
                }
            }

            return result;
        }

        /// <summary>
        /// Determines if the specified path is either a drive root or a UNC root.
        /// </summary>
        /// <param name="path">
        /// The path
        /// </param>
        /// <returns>
        /// True if the path is either a drive root or a UNC root, or false otherwise.
        /// </returns>
        private static bool IsPathRoot(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                return false;
            }

            bool isDriveRoot = string.Equals(path, Path.GetPathRoot(path), StringComparison.OrdinalIgnoreCase);
            bool isUNCRoot = IsUNCRoot(path);
            bool result = isDriveRoot || isUNCRoot;
            s_tracer.WriteLine("result = {0}; isDriveRoot = {1}; isUNCRoot = {2}", result, isDriveRoot, isUNCRoot);
            return result;
        }

        /// <summary>
        /// Normalizes the path that was passed in and returns it as a normalized
        /// path relative to the given basePath.
        /// </summary>
        /// <param name="path">
        /// A fully qualifiedpath to an item. The item must exist,
        /// or the provider writes out an error.
        /// </param>
        /// <param name="basePath">
        /// The path that the normalized path should be relative to.
        /// </param>
        /// <returns>
        /// A normalized path, relative to the given basePath.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override string NormalizeRelativePath(
            string path,
            string basePath)
        {
            if (string.IsNullOrEmpty(path) || !IsValidPath(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            basePath ??= string.Empty;

            s_tracer.WriteLine("basePath = {0}", basePath);

            string result = path;

            do // false loop
            {
                path = NormalizePath(path);
                path = EnsureDriveIsRooted(path);

                // If it's not fully normalized, normalize it.
                path = NormalizeRelativePathHelper(path, basePath);

                basePath = NormalizePath(basePath);
                basePath = EnsureDriveIsRooted(basePath);

                result = path;
                if (string.IsNullOrEmpty(result))
                {
                    break;
                }

                try
                {
                    string originalPathComparison = path;
                    if (!originalPathComparison.EndsWith(StringLiterals.DefaultPathSeparator))
                    {
                        originalPathComparison += StringLiterals.DefaultPathSeparator;
                    }

                    string basePathComparison = basePath;
                    if (!basePathComparison.EndsWith(StringLiterals.DefaultPathSeparator))
                    {
                        basePathComparison += StringLiterals.DefaultPathSeparator;
                    }

                    if (originalPathComparison.StartsWith(basePathComparison, StringComparison.OrdinalIgnoreCase))
                    {
                        if (!Utils.PathIsUnc(result))
                        {
                            // Add the base path back on so that it can be used for
                            // processing
                            if (!result.StartsWith(basePath, StringComparison.Ordinal))
                            {
                                result = MakePath(basePath, result);
                            }
                        }

                        if (IsPathRoot(result))
                        {
                            result = EnsureDriveIsRooted(result);
                        }
                        else
                        {
                            // Now ensure that we have the proper casing by
                            // getting the names of the files and directories that match
                            string directoryPath = GetParentPath(result, string.Empty);

                            if (string.IsNullOrEmpty(directoryPath))
                            {
                                return string.Empty;
                            }

#if UNIX
                            // We don't use the Directory.EnumerateFiles() for Unix because the path
                            // may contain additional globbing patterns such as '[ab]'
                            // which Directory.EnumerateFiles() processes, giving undesirable
                            // results in this context.
                            if (!File.Exists(result) && !Directory.Exists(result))
                            {
                                string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                                Exception e = new IOException(error);
                                WriteError(new ErrorRecord(
                                    e,
                                    "ItemDoesNotExist",
                                    ErrorCategory.ObjectNotFound,
                                    path));
                                break;
                            }
#else
                            string leafName = GetChildName(result);

                            // Use the Directory class to get the real path (this will
                            // ensure the proper casing
                            IEnumerable<string> files = Directory.EnumerateFiles(directoryPath, leafName);

                            if (files == null || !files.Any())
                            {
                                files = Directory.EnumerateDirectories(directoryPath, leafName);
                            }

                            if (files == null || !files.Any())
                            {
                                string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                                Exception e = new IOException(error);
                                WriteError(new ErrorRecord(
                                    e,
                                    "ItemDoesNotExist",
                                    ErrorCategory.ObjectNotFound,
                                    path));
                                break;
                            }

                            result = files.First();
#endif

                            if (result.StartsWith(basePath, StringComparison.Ordinal))
                            {
                                result = result.Substring(basePath.Length);
                            }
                            else
                            {
                                string error = StringUtil.Format(FileSystemProviderStrings.PathOutSideBasePath, path);
                                Exception e =
                                    new ArgumentException(error);
                                WriteError(new ErrorRecord(
                                    e,
                                    "PathOutSideBasePath",
                                    ErrorCategory.InvalidArgument,
                                    null));
                                break;
                            }
                        }
                    }
                }
                catch (ArgumentException argumentException)
                {
                    WriteError(new ErrorRecord(argumentException, "NormalizeRelativePathArgumentError", ErrorCategory.InvalidArgument, path));
                    break;
                }
                catch (DirectoryNotFoundException directoryNotFound)
                {
                    WriteError(new ErrorRecord(directoryNotFound, "NormalizeRelativePathDirectoryNotFoundError", ErrorCategory.ObjectNotFound, path));
                    break;
                }
                catch (IOException ioError)
                {
                    // IOException contains specific message about the error occurred and so no need for errordetails.
                    WriteError(new ErrorRecord(ioError, "NormalizeRelativePathIOError", ErrorCategory.ReadError, path));
                    break;
                }
                catch (UnauthorizedAccessException accessException)
                {
                    WriteError(new ErrorRecord(accessException, "NormalizeRelativePathUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
                    break;
                }
            } while (false);

            return result;
        }

        /// <summary>
        /// Normalizes the path that was passed in and returns the normalized path
        /// as a relative path to the basePath that was passed.
        /// </summary>
        /// <param name="path">
        /// A fully qualified provider specific path to an item. The item should exist
        /// or the provider should write out an error.
        /// </param>
        /// <param name="basePath">
        /// The path that the return value should be relative to.
        /// </param>
        /// <returns>
        /// A normalized path that is relative to the basePath that was passed. The
        /// provider should parse the path parameter, normalize the path, and then
        /// return the normalized path relative to the basePath.
        /// </returns>
        /// <remarks>
        /// This method does not have to be purely syntactical parsing of the path. It
        /// is encouraged that the provider actually use the path to lookup in its store
        /// and create a relative path that matches the casing, and standardized path syntax.
        ///
        /// Note, the base class implementation uses GetParentPath, GetChildName, and MakePath
        /// to normalize the path and then make it relative to basePath. All string comparisons
        /// are done using StringComparison.InvariantCultureIgnoreCase.
        /// </remarks>
        private string NormalizeRelativePathHelper(string path, string basePath)
        {
            if (path == null)
            {
                throw PSTraceSource.NewArgumentNullException(nameof(path));
            }

            if (path.Length == 0)
            {
                return string.Empty;
            }

            basePath ??= string.Empty;

            s_tracer.WriteLine("basePath = {0}", basePath);

#if !UNIX
            // Remove alternate data stream references
            // See if they've used the inline stream syntax. They have more than one colon.
            string alternateDataStream = string.Empty;
            int firstColon = path.IndexOf(':');
            int secondColon = path.IndexOf(':', firstColon + 1);
            if (secondColon > 0)
            {
                string newPath = path.Substring(0, secondColon);
                alternateDataStream = path.Replace(newPath, string.Empty);
                path = newPath;
            }
#endif

            string result = path;

            do // false loop
            {
                // Convert to the correct path separators and trim trailing separators
                path = path.Replace(StringLiterals.AlternatePathSeparator, StringLiterals.DefaultPathSeparator);
                string originalPath = path;

                path = path.TrimEnd(StringLiterals.DefaultPathSeparator);
                basePath = basePath.Replace(StringLiterals.AlternatePathSeparator, StringLiterals.DefaultPathSeparator);
                basePath = basePath.TrimEnd(StringLiterals.DefaultPathSeparator);

                path = RemoveRelativeTokens(path);

                // See if the base and the path are already the same. We resolve this to
                // ..\Leaf, since resolving "." to "." doesn't offer much information.
                if (string.Equals(path, basePath, StringComparison.OrdinalIgnoreCase) &&
                    (!originalPath.EndsWith(StringLiterals.DefaultPathSeparator)))
                {
                    string childName = GetChildName(path);
                    result = MakePath("..", childName);
                    break;
                }

                Stack<string> tokenizedPathStack = null;

                // If the base path isn't really a base, then we resolve to a parent
                // path (such as ../../foo)
                // For example: base = c:/temp/bar/baz
                //              path = c:/temp/foo
                if ((
                    !(path + StringLiterals.DefaultPathSeparator).StartsWith(
                    basePath + StringLiterals.DefaultPathSeparator, StringComparison.OrdinalIgnoreCase)) &&
                    (!string.IsNullOrEmpty(basePath))
                    )
                {
                    result = string.Empty;
                    string commonBase = GetCommonBase(path, basePath);

                    Stack<string> parentNavigationStack = TokenizePathToStack(basePath, commonBase);
                    int parentPopCount = parentNavigationStack.Count;

                    if (string.IsNullOrEmpty(commonBase))
                    {
                        parentPopCount--;
                    }

                    for (int leafCounter = 0; leafCounter < parentPopCount; leafCounter++)
                    {
                        result = MakePath("..", result);
                    }

                    // This is true if we get passed a base path like:
                    //    c:\directory1\directory2
                    // and an actual path of
                    //    c:\directory1
                    // Which happens when the user is in c:\directory1\directory2
                    // and wants to resolve something like:
                    // ..\..\dir*
                    // In that case (as above,) we keep the ..\..\directory1
                    // instead of ".." as would usually be returned
                    if (!string.IsNullOrEmpty(commonBase))
                    {
                        if (string.Equals(path, commonBase, StringComparison.OrdinalIgnoreCase) &&
                            (!path.EndsWith(StringLiterals.DefaultPathSeparator)))
                        {
                            string childName = GetChildName(path);
                            result = MakePath("..", result);
                            result = MakePath(result, childName);
                        }
                        else
                        {
                            string[] childNavigationItems = TokenizePathToStack(path, commonBase).ToArray();

                            for (int leafCounter = 0; leafCounter < childNavigationItems.Length; leafCounter++)
                            {
                                result = MakePath(result, childNavigationItems[leafCounter]);
                            }
                        }
                    }
                }
                // Otherwise, we resolve to a child path (such as foo/bar)
                else
                {
                    // If the path is a root, then the result will either be empty or the root depending
                    // on the value of basePath.
                    if (IsPathRoot(path))
                    {
                        if (string.IsNullOrEmpty(basePath))
                        {
                            result = path;
                            break;
                        }
                        else
                        {
                            result = string.Empty;
                            break;
                        }
                    }

                    tokenizedPathStack = TokenizePathToStack(path, basePath);

                    // Now we have to normalize the path
                    // by processing each token on the stack
                    Stack<string> normalizedPathStack;

                    try
                    {
                        normalizedPathStack = NormalizeThePath(basePath, tokenizedPathStack);
                    }
                    catch (ArgumentException argumentException)
                    {
                        WriteError(new ErrorRecord(argumentException, "NormalizeRelativePathHelperArgumentError", ErrorCategory.InvalidArgument, null));
                        result = null;
                        break;
                    }

                    // Now that the path has been normalized, create the relative path
                    result = CreateNormalizedRelativePathFromStack(normalizedPathStack);
                }
            } while (false);

#if !UNIX
            if (!string.IsNullOrEmpty(alternateDataStream))
            {
                result += alternateDataStream;
            }
#endif

            return result;
        }

        private string RemoveRelativeTokens(string path)
        {
            string testPath = path.Replace('/', '\\');
            if (
                !testPath.Contains('\\') ||
                testPath.StartsWith(".\\", StringComparison.Ordinal) ||
                testPath.StartsWith("..\\", StringComparison.Ordinal) ||
                testPath.EndsWith("\\.", StringComparison.Ordinal) ||
                testPath.EndsWith("\\..", StringComparison.Ordinal) ||
                testPath.Contains("\\.\\", StringComparison.Ordinal) ||
                testPath.Contains("\\..\\", StringComparison.Ordinal))
            {
                try
                {
                    Stack<string> tokenizedPathStack = TokenizePathToStack(path, string.Empty);
                    Stack<string> normalizedPath = NormalizeThePath(string.Empty, tokenizedPathStack);
                    return CreateNormalizedRelativePathFromStack(normalizedPath);
                }
                catch (UnauthorizedAccessException)
                {
                    // Catch any errors here, as we may be in an AppContainer
                }
            }

            return path;
        }

        /// <summary>
        /// Get the common base path of two paths.
        /// </summary>
        /// <param name="path1">One path.</param>
        /// <param name="path2">Another path.</param>
        private string GetCommonBase(string path1, string path2)
        {
            // Always see if the shorter path is a substring of the
            // longer path. If it is not, take the child off of the longer
            // path and compare again.
            while (!string.Equals(path1, path2, StringComparison.OrdinalIgnoreCase))
            {
                if (path2.Length > path1.Length)
                {
                    path2 = GetParentPath(path2, null);
                }
                else
                {
                    path1 = GetParentPath(path1, null);
                }
            }

            return path1;
        }

        /// <summary>
        /// Tokenizes the specified path onto a stack.
        /// </summary>
        /// <param name="path">
        /// The path to tokenize.
        /// </param>
        /// <param name="basePath">
        /// The base part of the path that should not be tokenized.
        /// </param>
        /// <returns>
        /// A stack containing the tokenized path with leaf elements on the bottom
        /// of the stack and the most ancestral parent at the top.
        /// </returns>
        private Stack<string> TokenizePathToStack(string path, string basePath)
        {
            Stack<string> tokenizedPathStack = new Stack<string>();

            string tempPath = path;
            string previousParent = path;

            while (tempPath.Length > basePath.Length)
            {
                // Get the child name and push it onto the stack
                // if its valid
                string childName = GetChildName(tempPath);
                if (string.IsNullOrEmpty(childName))
                {
                    // Push the parent on and then stop
                    s_tracer.WriteLine("tokenizedPathStack.Push({0})", tempPath);
                    tokenizedPathStack.Push(tempPath);
                    break;
                }

                s_tracer.WriteLine("tokenizedPathStack.Push({0})", childName);
                tokenizedPathStack.Push(childName);

                // Get the parent path and verify if we have to continue
                // tokenizing
                // We are done if the remaining path is:
                // - the same as the previous path
                // - a UNC path that is the root of a UNC share
                // - not a UNC path and the string length is less than or
                //   equal to 3. "C:\"
                tempPath = GetParentPath(tempPath, basePath);
                if (tempPath.Length >= previousParent.Length ||
                    IsPathRoot(tempPath))
                {
                    if (string.IsNullOrEmpty(basePath))
                    {
                        s_tracer.WriteLine("tokenizedPathStack.Push({0})", tempPath);
                        tokenizedPathStack.Push(tempPath);
                    }

                    break;
                }

                previousParent = tempPath;
            }

            return tokenizedPathStack;
        }

        /// <summary>
        /// Given the tokenized path, the relative path elements are removed.
        /// </summary>
        /// <param name="basepath">
        ///   String containing basepath for which we are trying to find the relative path.
        /// </param>
        /// <param name="tokenizedPathStack">
        /// A stack containing path elements where the leaf most element is at
        /// the bottom of the stack and the most ancestral parent is on the top.
        /// Generally this stack comes from TokenizePathToStack().
        /// </param>
        /// <returns>
        /// A stack in reverse order with the path elements normalized and all relative
        /// path tokens removed.
        /// </returns>
        private Stack<string> NormalizeThePath(string basepath, Stack<string> tokenizedPathStack)
        {
            Stack<string> normalizedPathStack = new Stack<string>();
            string currentPath = basepath;

            while (tokenizedPathStack.Count > 0)
            {
                string childName = tokenizedPathStack.Pop();

                s_tracer.WriteLine("childName = {0}", childName);

                // Ignore the current directory token
                if (childName.Equals(".", StringComparison.OrdinalIgnoreCase))
                {
                    // Just ignore it and move on.
                    continue;
                }
                else if (childName.Equals("..", StringComparison.OrdinalIgnoreCase))
                {
                    if (normalizedPathStack.Count > 0)
                    {
                        // Pop the result and continue processing
                        string poppedName = normalizedPathStack.Pop();
                        // update our currentpath to reflect the change.
                        if (currentPath.Length > poppedName.Length)
                        {
                            currentPath = currentPath.Substring(0, currentPath.Length - poppedName.Length - 1);
                        }
                        else
                        {
                            currentPath = string.Empty;
                        }

                        s_tracer.WriteLine("normalizedPathStack.Pop() : {0}", poppedName);
                        continue;
                    }
                    else
                    {
                        throw PSTraceSource.NewArgumentException("path", FileSystemProviderStrings.PathOutSideBasePath);
                    }
                }
                else
                {
                    currentPath = MakePath(currentPath, childName);

                    var fsinfo = GetFileSystemInfo(currentPath, out bool _);

                    // Clean up the child name to proper casing and short-path
                    // expansion if required. Also verify that .NET hasn't over-normalized
                    // the path
                    if (fsinfo != null)
                    {
                        // This might happen if you've passed a child name of two or more dots,
                        // which the .NET APIs treat as the parent directory
                        if (fsinfo.FullName.Length < currentPath.Length)
                        {
                            throw PSTraceSource.NewArgumentException("path", FileSystemProviderStrings.ItemDoesNotExist, currentPath);
                        }

                        // Expand the short file name
                        if (fsinfo.Name.Length >= childName.Length)
                        {
                            childName = fsinfo.Name;
                        }
                    }
                    else
                    {
                        // We couldn't find the item
                        if (tokenizedPathStack.Count == 0)
                        {
                            throw PSTraceSource.NewArgumentException("path", FileSystemProviderStrings.ItemDoesNotExist, currentPath);
                        }
                    }
                }

                s_tracer.WriteLine("normalizedPathStack.Push({0})", childName);
                normalizedPathStack.Push(childName);
            }

            return normalizedPathStack;
        }

        /// <summary>
        /// Pops each leaf element of the stack and uses MakePath to generate the relative path.
        /// </summary>
        /// <param name="normalizedPathStack">
        /// The stack containing the leaf elements of the path.
        /// </param>
        /// <returns>
        /// A path that is made up of the leaf elements on the given stack.
        /// </returns>
        /// <remarks>
        /// The elements on the stack start from the leaf element followed by its parent
        /// followed by its parent, etc. Each following element on the stack is the parent
        /// of the one before it.
        /// </remarks>
        private string CreateNormalizedRelativePathFromStack(Stack<string> normalizedPathStack)
        {
            string leafElement = string.Empty;

            while (normalizedPathStack.Count > 0)
            {
                if (string.IsNullOrEmpty(leafElement))
                {
                    leafElement = normalizedPathStack.Pop();
                }
                else
                {
                    string parentElement = normalizedPathStack.Pop();
                    leafElement = MakePath(parentElement, leafElement);
                }
            }

            return leafElement;
        }

        /// <summary>
        /// Gets the name of the leaf element of the specified path.
        /// </summary>
        /// <param name="path">
        /// The fully qualified path to the item.
        /// </param>
        /// <returns>
        /// The leaf element of the specified path.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override string GetChildName(string path)
        {
            // Verify the parameters

            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            // Normalize the path
            path = path.Replace(StringLiterals.AlternatePathSeparator, StringLiterals.DefaultPathSeparator);

            // Trim trailing back slashes
            path = path.TrimEnd(StringLiterals.DefaultPathSeparator);

            string result = null;

            int separatorIndex = path.LastIndexOf(StringLiterals.DefaultPathSeparator);

            if (separatorIndex == -1)
            {
                // Since there was no path separator return an empty string
                result = EnsureDriveIsRooted(path);
            }
            else
            {
                result = path.Substring(separatorIndex + 1);
            }

            return result;
        }

        private static string EnsureDriveIsRooted(string path)
        {
            string result = path;

            // Find the drive separator
            int index = path.IndexOf(':');

            if (index != -1)
            {
                // if the drive separator is the end of the path, add
                // the root path separator back
                if (index + 1 == path.Length)
                {
                    result = path + StringLiterals.DefaultPathSeparator;
                }
            }

            return result;
        }

        /// <summary>
        /// Determines if the item at the specified path is a directory.
        /// </summary>
        /// <param name="path">
        /// The path to the file or directory to check.
        /// </param>
        /// <returns>
        /// True if the item at the specified path is a directory.
        /// False otherwise.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        protected override bool IsItemContainer(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            return Directory.Exists(path);
        }

        #region MoveItem

        /// <summary>
        /// Moves an item at the specified path to the given destination.
        /// </summary>
        /// <param name="path">
        /// The path of the item to move.
        /// </param>
        /// <param name="destination">
        /// The path of the destination.
        /// </param>
        /// <returns>
        /// Nothing.  Moved items are written to the context's pipeline.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        ///     destination is null or empty.
        /// </exception>
        protected override void MoveItem(
            string path,
            string destination)
        {
            // Check the parameters

            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            if (string.IsNullOrEmpty(destination))
            {
                throw PSTraceSource.NewArgumentException(nameof(destination));
            }

            path = NormalizePath(path);
            destination = NormalizePath(destination);

            // Verify that the target doesn't represent a device name
            if (PathIsReservedDeviceName(destination, "MoveError"))
            {
                return;
            }

            try
            {
                bool isContainer = IsItemContainer(path);
                s_tracer.WriteLine("Moving {0} to {1}", path, destination);

                if (isContainer)
                {
                    // Get the DirectoryInfo
                    DirectoryInfo dir = new DirectoryInfo(path);

                    if (ItemExists(destination) &&
                        IsItemContainer(destination))
                    {
                        destination = MakePath(destination, dir.Name);
                    }

                    // Don't allow moving a directory into itself or its sub-directory.
                    string pathWithoutEndingSeparator = Path.TrimEndingDirectorySeparator(path);
                    if (destination.StartsWith(pathWithoutEndingSeparator + Path.DirectorySeparatorChar)
                        || destination.Equals(pathWithoutEndingSeparator, StringComparison.OrdinalIgnoreCase))
                    {
                        string error = StringUtil.Format(FileSystemProviderStrings.TargetCannotBeSubdirectoryOfSource, destination);
                        var e = new IOException(error);
                        WriteError(new ErrorRecord(e, "MoveItemArgumentError", ErrorCategory.InvalidArgument, destination));
                        return;
                    }

                    // Get the confirmation text
                    string action = FileSystemProviderStrings.MoveItemActionDirectory;

                    string resource = StringUtil.Format(FileSystemProviderStrings.MoveItemResourceFileTemplate, dir.FullName, destination);

                    // Confirm the move with the user
                    if (ShouldProcess(resource, action))
                    {
                        // Now move the directory
                        MoveDirectoryInfoItem(dir, destination, Force);
                    }
                }
                else
                {
                    // Get the FileInfo
                    FileInfo file = new FileInfo(path);

                    Dbg.Diagnostics.Assert(
                        file != null,
                        "FileInfo should be throwing an exception but it's " +
                        "returning null instead");

                    if (IsItemContainer(destination))
                    {
                        // Construct the new file path from the destination
                        // directory and the file name
                        destination = MakePath(destination, file.Name);
                    }

                    // Get the confirmation text
                    string action = FileSystemProviderStrings.MoveItemActionFile;

                    string resource = StringUtil.Format(FileSystemProviderStrings.MoveItemResourceFileTemplate, file.FullName, destination);

                    // Confirm the move with the user
                    if (ShouldProcess(resource, action))
                    {
                        MoveFileInfoItem(file, destination, Force, true);
                    }
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "MoveItemArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "MoveItemIOError", ErrorCategory.WriteError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "MoveItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
        }

        private void MoveFileInfoItem(
            FileInfo file,
            string destination,
            bool force,
            bool output)
        {
            Dbg.Diagnostics.Assert(
                file != null,
                "The caller should verify file.");

            Dbg.Diagnostics.Assert(
                !string.IsNullOrEmpty(destination),
                "THe caller should verify destination.");

            try
            {
                // Move the file
                file.MoveTo(destination);

                if (output)
                {
                    WriteItemObject(
                        file,
                        file.FullName,
                        false);
                }
            }
            catch (System.UnauthorizedAccessException unauthorizedAccess)
            {
                // This error is thrown when the readonly bit is set.
                if (force)
                {
                    try
                    {
                        // mask off the readonly and hidden bits and try again
                        file.Attributes &= ~(FileAttributes.ReadOnly | FileAttributes.Hidden);

                        file.MoveTo(destination);

                        if (output)
                        {
                            WriteItemObject(file, file.FullName, false);
                        }
                    }
                    catch (Exception e)
                    {
                        if ((e is IOException) ||
                            (e is ArgumentNullException) ||
                            (e is ArgumentException) ||
                            (e is System.Security.SecurityException) ||
                            (e is UnauthorizedAccessException) ||
                            (e is FileNotFoundException) ||
                            (e is DirectoryNotFoundException) ||
                            (e is PathTooLongException) ||
                            (e is NotSupportedException))
                        {
                            // If any exception occurs return the original error
                            WriteError(new ErrorRecord(unauthorizedAccess, "MoveFileInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, file));
                        }
                        else
                            throw;
                    }
                }
                else
                {
                    WriteError(new ErrorRecord(unauthorizedAccess, "MoveFileInfoItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, file));
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "MoveFileInfoItemArgumentError", ErrorCategory.InvalidArgument, file));
            }
            catch (IOException ioException)
            {
                // check if destination file exists. if force is specified then we should delete the destination before moving
                if (force && File.Exists(destination))
                {
                    FileInfo destfile = new FileInfo(destination);
                    if (destfile != null)
                    {
                        try
                        {
                            // Make sure the file is not read only
                            destfile.Attributes &= ~(FileAttributes.ReadOnly | FileAttributes.Hidden);
                            destfile.Delete();
                            file.MoveTo(destination);

                            if (output)
                            {
                                WriteItemObject(file, file.FullName, false);
                            }
                        }
                        catch (Exception exception)
                        {
                            if ((exception is FileNotFoundException) ||
                                (exception is DirectoryNotFoundException) ||
                                (exception is UnauthorizedAccessException) ||
                                (exception is System.Security.SecurityException) ||
                                (exception is ArgumentException) ||
                                (exception is PathTooLongException) ||
                                (exception is NotSupportedException) ||
                                (exception is ArgumentNullException) ||
                                (exception is IOException))
                            {
                                // IOException contains specific message about the error occurred and so no need for errordetails.
                                WriteError(new ErrorRecord(ioException, "MoveFileInfoItemIOError", ErrorCategory.WriteError, destfile));
                            }
                            else
                                throw;
                        }
                    }
                    else
                    {
                        // IOException contains specific message about the error occurred and so no need for errordetails.
                        WriteError(new ErrorRecord(ioException, "MoveFileInfoItemIOError", ErrorCategory.WriteError, file));
                    }
                }
                else
                {
                    // IOException contains specific message about the error occurred and so no need for errordetails.
                    WriteError(new ErrorRecord(ioException, "MoveFileInfoItemIOError", ErrorCategory.WriteError, file));
                }
            }
        }

        private void MoveDirectoryInfoItem(
            DirectoryInfo directory,
            string destination,
            bool force)
        {
            Dbg.Diagnostics.Assert(
                directory != null,
                "The caller should verify directory.");

            Dbg.Diagnostics.Assert(
                !string.IsNullOrEmpty(destination),
                "The caller should verify destination.");

            try
            {
                MoveDirectoryInfoUnchecked(directory, destination, force);

                WriteItemObject(
                    directory,
                    directory.FullName,
                    true);
            }
            catch (System.UnauthorizedAccessException unauthorizedAccess)
            {
                // This error is thrown when the readonly bit is set.
                if (force)
                {
                    try
                    {
                        // mask off the readonly and hidden bits and try again
                        directory.Attributes &= ~(FileAttributes.ReadOnly | FileAttributes.Hidden);

                        MoveDirectoryInfoUnchecked(directory, destination, force);

                        WriteItemObject(directory, directory.FullName, true);
                    }
                    catch (IOException)
                    {
                        WriteError(new ErrorRecord(unauthorizedAccess, "MoveDirectoryItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, directory));
                    }
                    catch (Exception exception)
                    {
                        if ((exception is FileNotFoundException) ||
                            (exception is ArgumentNullException) ||
                            (exception is DirectoryNotFoundException) ||
                            (exception is System.Security.SecurityException) ||
                            (exception is ArgumentException))
                        {
                            WriteError(new ErrorRecord(unauthorizedAccess, "MoveDirectoryItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, directory));
                        }
                        else
                            throw;
                    }
                }
                else
                {
                    WriteError(new ErrorRecord(unauthorizedAccess, "MoveDirectoryItemUnauthorizedAccessError", ErrorCategory.PermissionDenied, directory));
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "MoveDirectoryItemArgumentError", ErrorCategory.InvalidArgument, directory));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "MoveDirectoryItemIOError", ErrorCategory.WriteError, directory));
            }
        }

        /// <summary>
        /// Implements the file move operation for directories without handling any error scenarios.
        /// In particular, this attempts to rename or copy+delete the file,
        /// but passes any exceptional behavior through to the caller.
        /// </summary>
        /// <param name="directory">The directory to move.</param>
        /// <param name="destinationPath">The destination path to move the directory to.</param>
        /// <param name="force">If true, force move the directory, overwriting anything at the destination.</param>
        private void MoveDirectoryInfoUnchecked(DirectoryInfo directory, string destinationPath, bool force)
        {
            try
            {
                if (InternalTestHooks.ThrowExdevErrorOnMoveDirectory)
                {
                    throw new IOException("Invalid cross-device link");
                }

                directory.MoveTo(destinationPath);
            }
#if UNIX
            // This is the errno returned by the rename() syscall
            // when an item is attempted to be renamed across filesystem mount boundaries.
            // 0x80131620 is returned if the source and destination do not have the same root path
            catch (IOException e) when (e.HResult == 18 || e.HResult == -2146232800)
#else
            // 0x80070005 ACCESS_DENIED is returned when trying to move files across volumes like DFS
            // 0x80131620 is returned if the source and destination do not have the same root path
            catch (IOException e) when (e.HResult == -2147024891 || e.HResult == -2146232800)
#endif
            {
                // Rather than try to ascertain whether we can rename a directory ahead of time,
                // it's both faster and more correct to try to rename it and fall back to copy/deleting it
                // See also: https://github.com/coreutils/coreutils/blob/439741053256618eb651e6d43919df29625b8714/src/mv.c#L212-L216
                CopyAndDelete(directory, destinationPath, force);
            }
        }

        private void CopyAndDelete(DirectoryInfo directory, string destination, bool force)
        {
            if (!ItemExists(destination))
            {
                CreateDirectory(destination, false);
            }
            else if (ItemExists(destination) && !IsItemContainer(destination))
            {
                string errorMessage = StringUtil.Format(FileSystemProviderStrings.DirectoryExist, destination);
                Exception e = new IOException(errorMessage);

                WriteError(new ErrorRecord(
                    e,
                    "DirectoryExist",
                    ErrorCategory.ResourceExists,
                    destination));
                return;
            }

            foreach (FileInfo file in directory.EnumerateFiles())
            {
                MoveFileInfoItem(file, Path.Combine(destination, file.Name), force, false);
            }

            foreach (DirectoryInfo dir in directory.EnumerateDirectories())
            {
                CopyAndDelete(dir, Path.Combine(destination, dir.Name), force);
            }

            if (!directory.EnumerateDirectories().Any() && !directory.EnumerateFiles().Any())
            {
                RemoveItem(directory.FullName, false);
            }
        }

        #endregion MoveItem

        #endregion NavigationCmdletProvider members

        #region IPropertyCmdletProvider

        /// <summary>
        /// Gets a property for the given item.
        /// </summary>
        /// <param name="path">The fully qualified path to the item.</param>
        /// <param name="providerSpecificPickList">
        /// The list of properties to get.  Examples include "Attributes", "LastAccessTime,"
        /// and other properties defined by
        /// <see cref="System.IO.DirectoryInfo"/> and
        /// <see cref="System.IO.FileInfo"/>
        /// </param>
        public void GetProperty(string path, Collection<string> providerSpecificPickList)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            PSObject result = null;

            try
            {
                var fileSystemObject = GetFileSystemInfo(path, out bool isDirectory);

                if (fileSystemObject == null)
                {
                    string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                    Exception e = new IOException(error);
                    WriteError(new ErrorRecord(
                        e,
                        "ItemDoesNotExist",
                        ErrorCategory.ObjectNotFound,
                        path));
                }
                else
                {
                    // Finally get the properties
                    if (providerSpecificPickList == null || providerSpecificPickList.Count == 0)
                    {
                        result = PSObject.AsPSObject(fileSystemObject);
                    }
                    else
                    {
                        foreach (string property in providerSpecificPickList)
                        {
                            if (property != null && property.Length > 0)
                            {
                                try
                                {
                                    PSObject mshObject = PSObject.AsPSObject(fileSystemObject);
                                    PSMemberInfo member = mshObject.Properties[property];
                                    object value;
                                    if (member != null)
                                    {
                                        value = member.Value;
                                        result ??= new PSObject();

                                        result.Properties.Add(new PSNoteProperty(property, value));
                                    }
                                    else
                                    {
                                        string error =
                                            StringUtil.Format(
                                                FileSystemProviderStrings.PropertyNotFound,
                                                property);
                                        Exception e = new IOException(error);
                                        WriteError(new ErrorRecord(e, "GetValueError", ErrorCategory.ReadError, property));
                                    }
                                }
                                catch (GetValueException exception)
                                {
                                    WriteError(new ErrorRecord(exception, "GetValueError", ErrorCategory.ReadError, property));
                                }
                            }
                        }
                    }
                }
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "GetPropertyArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "GetPropertyIOError", ErrorCategory.ReadError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                WriteError(new ErrorRecord(accessException, "GetPropertyUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }

            if (result != null)
            {
                WritePropertyObject(result, path);
            }
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the get-itemproperty cmdlet.
        /// This feature is not required by the File System provider.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <param name="providerSpecificPickList">
        /// A list of properties that should be retrieved. If this parameter is null
        /// or empty, all properties should be retrieved.
        /// </param>
        /// <returns>
        /// Null.  This feature is not required by the File System provider.
        /// </returns>
        public object GetPropertyDynamicParameters(
            string path,
            Collection<string> providerSpecificPickList)
        {
            return null;
        }

        /// <summary>
        /// Sets the specified properties on the item at the given path.
        /// </summary>
        /// <param name="path">
        /// The path of the item on which to set the properties.
        /// </param>
        /// <param name="propertyToSet">
        /// A PSObject which contains a collection of the names and values
        /// of the properties to be set.  The File System provider supports setting
        /// only the "Attributes" property.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        /// <exception cref="System.ArgumentNullException">
        ///     propertyToSet is null.
        /// </exception>
        public void SetProperty(string path, PSObject propertyToSet)
        {
            // verify parameters

            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            if (propertyToSet == null)
            {
                throw PSTraceSource.NewArgumentNullException(nameof(propertyToSet));
            }

            path = NormalizePath(path);

            PSObject results = new PSObject();

            var fsinfo = GetFileSystemInfo(path, out bool isDirectory);

            // Create a PSObject with either a DirectoryInfo or FileInfo object at its core.
            if (fsinfo != null)
            {
                PSObject fileSystemInfoShell = PSObject.AsPSObject(fsinfo);

                bool propertySet = false;

                foreach (PSMemberInfo property in propertyToSet.Properties)
                {
                    object propertyValue = property.Value;

                    // Get the confirmation text
                    string action = null;

                    if (isDirectory)
                    {
                        action = FileSystemProviderStrings.SetPropertyActionDirectory;
                    }
                    else
                    {
                        action = FileSystemProviderStrings.SetPropertyActionFile;
                    }

                    string resourceTemplate = FileSystemProviderStrings.SetPropertyResourceTemplate;

                    string propertyValueString;

                    try
                    {
                        // Use a PSObject to get the string representation of the property value
                        PSObject propertyValuePSObject = PSObject.AsPSObject(propertyValue);
                        propertyValueString = propertyValuePSObject.ToString();
                    }
                    catch (Exception e)
                    {
                        Dbg.Diagnostics.Assert(
                            false,
                            "FileSystemProvider.SetProperty exception " + e.Message);
                        throw;
                    }

                    string resource =
                        string.Format(
                            Host.CurrentCulture,
                            resourceTemplate,
                            path,
                            property.Name,
                            propertyValueString);

                    // Confirm the set with the user
                    if (ShouldProcess(resource, action))
                    {
                        PSObject mshObject = PSObject.AsPSObject(fileSystemInfoShell);
                        PSMemberInfo member = mshObject.Properties[property.Name];

                        if (member != null)
                        {
                            if (string.Equals(property.Name, "attributes", StringComparison.OrdinalIgnoreCase))
                            {
                                FileAttributes attributes;

                                if (propertyValue is FileAttributes)
                                    attributes = (FileAttributes)propertyValue;
                                else
                                    attributes = (FileAttributes)Enum.Parse(typeof(FileAttributes), propertyValueString, true);

                                if ((attributes & ~(FileAttributes.Archive | FileAttributes.Hidden |
                                                        FileAttributes.Normal | FileAttributes.ReadOnly | FileAttributes.System)) != 0)
                                {
                                    string error =
                                        StringUtil.Format(
                                            FileSystemProviderStrings.AttributesNotSupported,
                                            property);
                                    Exception e = new IOException(error);
                                    WriteError(new ErrorRecord(e, "SetPropertyError", ErrorCategory.ReadError, property));
                                    continue;
                                }
                            }

                            member.Value = propertyValue;
                            results.Properties.Add(new PSNoteProperty(property.Name, propertyValue));
                            propertySet = true;
                        }
                        else
                        {
                            string error =
                                StringUtil.Format(
                                    FileSystemProviderStrings.PropertyNotFound,
                                    property);
                            Exception e = new IOException(error);
                            WriteError(new ErrorRecord(e, "SetPropertyError", ErrorCategory.ReadError, property));
                        }
                    }
                }

                if (propertySet)
                {
                    WritePropertyObject(results, path);
                }
            }
            else
            {
                string error = StringUtil.Format(FileSystemProviderStrings.ItemDoesNotExist, path);
                Exception e = new IOException(error);
                WriteError(new ErrorRecord(
                    e,
                    "ItemDoesNotExist",
                    ErrorCategory.ObjectNotFound,
                    path));
            }
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the set-itemproperty cmdlet.
        /// This feature is not required by the File System provider.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to set the dynamic parameters.
        /// </param>
        /// <param name="propertyValue">
        /// A PSObject which contains a collection of the name, type, value
        /// of the properties to be set.
        /// </param>
        /// <returns>
        /// Null.  This feature is not required by the File System provider.
        /// </returns>
        public object SetPropertyDynamicParameters(
            string path,
            PSObject propertyValue)
        {
            return null;
        }

        /// <summary>
        /// Clears the specified properties on the item at the given path.
        /// The File System provider supports only the "Attributes" property.
        /// </summary>
        /// <param name="path">
        /// The path of the item on which to clear the properties.
        /// </param>
        /// <param name="propertiesToClear">
        /// A collection of the names of the properties to clear.  The File System
        /// provider supports clearing only the "Attributes" property.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     Path is null or empty.
        /// </exception>
        /// <exception cref="System.ArgumentNullException">
        ///     propertiesToClear is null or count is zero.
        /// </exception>
        public void ClearProperty(
            string path,
            Collection<string> propertiesToClear)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            if (propertiesToClear == null ||
                propertiesToClear.Count == 0)
            {
                throw PSTraceSource.NewArgumentNullException(nameof(propertiesToClear));
            }

            // Only the attributes property can be cleared
            if (propertiesToClear.Count > 1 ||
                Host.CurrentCulture.CompareInfo.Compare("Attributes", propertiesToClear[0], CompareOptions.IgnoreCase) != 0)
            {
                throw PSTraceSource.NewArgumentException(nameof(propertiesToClear), FileSystemProviderStrings.CannotClearProperty);
            }

            try
            {
                // Now the only entry in the array should be the Attributes, so clear them
                FileSystemInfo fileSystemInfo = null;

                // Get the confirmation text
                string action = null;

                bool isContainer = IsItemContainer(path);
                if (isContainer)
                {
                    action = FileSystemProviderStrings.ClearPropertyActionDirectory;

                    fileSystemInfo = new DirectoryInfo(path);
                }
                else
                {
                    action = FileSystemProviderStrings.ClearPropertyActionFile;

                    fileSystemInfo = new FileInfo(path);
                }

                string resourceTemplate = FileSystemProviderStrings.ClearPropertyResourceTemplate;

                string resource =
                    string.Format(
                        Host.CurrentCulture,
                        resourceTemplate,
                        fileSystemInfo.FullName,
                        propertiesToClear[0]);

                // Confirm the set with the user
                if (ShouldProcess(resource, action))
                {
                    fileSystemInfo.Attributes = FileAttributes.Normal;
                    PSObject result = new PSObject();
                    result.Properties.Add(new PSNoteProperty(propertiesToClear[0], fileSystemInfo.Attributes));

                    // Now write out the attribute that was cleared.
                    WritePropertyObject(result, path);
                }
            }
            catch (UnauthorizedAccessException unauthorizedAccessException)
            {
                WriteError(new ErrorRecord(unauthorizedAccessException, "ClearPropertyUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "ClearPropertyArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "ClearPropertyIOError", ErrorCategory.WriteError, path));
            }
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the clear-itemproperty cmdlet.
        /// This feature is not required by the File System provider.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to set the dynamic parameters.
        /// </param>
        /// <param name="propertiesToClear">
        /// A collection of the names of the properties to clear.
        /// </param>
        /// <returns>
        /// Null.  This feature is not required by the File System provider.
        /// </returns>
        public object ClearPropertyDynamicParameters(
            string path,
            Collection<string> propertiesToClear)
        {
            return null;
        }

        #endregion IPropertyCmdletProvider

        #region IContentCmdletProvider

        /// <summary>
        /// Creates an instance of the FileSystemContentStream class, opens
        /// the specified file for reading, and returns the IContentReader interface
        /// to it.
        /// </summary>
        /// <param name="path">
        /// The path of the file to be opened for reading.
        /// </param>
        /// <returns>
        /// An IContentReader for the specified file.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        public IContentReader GetContentReader(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            // Defaults for the file read operation
            string delimiter = "\n";
            Encoding encoding = Encoding.Default;
            bool waitForChanges = false;

            bool streamTypeSpecified = false;
            bool usingByteEncoding = false;
            bool delimiterSpecified = false;
            bool isRawStream = false;
            string streamName = null;

            // Get the dynamic parameters.
            // They override the defaults specified above.
            if (DynamicParameters != null)
            {
                FileSystemContentReaderDynamicParameters dynParams =
                    DynamicParameters as FileSystemContentReaderDynamicParameters;

                if (dynParams != null)
                {
                    // -raw is not allowed when -first,-last or -wait is specified
                    // this call will validate that and throws.
                    ValidateParameters(dynParams.Raw);

                    isRawStream = dynParams.Raw;

                    // Get the delimiter
                    delimiterSpecified = dynParams.DelimiterSpecified;
                    if (delimiterSpecified)
                        delimiter = dynParams.Delimiter;

                    // Get the stream type
                    usingByteEncoding = dynParams.AsByteStream;
                    streamTypeSpecified = dynParams.WasStreamTypeSpecified;

                    if (usingByteEncoding && streamTypeSpecified)
                    {
                        WriteWarning(FileSystemProviderStrings.EncodingNotUsed);
                    }

                    if (streamTypeSpecified)
                    {
                        encoding = dynParams.Encoding;
                    }

                    // Get the wait value
                    waitForChanges = dynParams.Wait;

#if !UNIX
                    // Get the stream name
                    streamName = dynParams.Stream;
#endif
                }
            }

#if !UNIX
            // See if they've used the inline stream syntax. They have more than one colon.
            int firstColon = path.IndexOf(':');
            int secondColon = path.IndexOf(':', firstColon + 1);
            if (secondColon > 0)
            {
                streamName = path.Substring(secondColon + 1);
                path = path.Remove(secondColon);
            }
#endif

            FileSystemContentReaderWriter stream = null;

            try
            {
                // Get-Content will write a non-terminating error if the target is a directory.
                // On Windows, the streamName must be null or empty for it to write the error. Otherwise, the
                // alternate data stream is not a directory, even if it's set on a directory.
                if (Directory.Exists(path)
#if !UNIX
                    && string.IsNullOrEmpty(streamName)
#endif
                    )
                {
                    string errMsg = StringUtil.Format(SessionStateStrings.GetContainerContentException, path);
                    ErrorRecord error = new ErrorRecord(new InvalidOperationException(errMsg), "GetContainerContentException", ErrorCategory.InvalidOperation, null);
                    WriteError(error);
                    return stream;
                }

                // Users can't both read as bytes, and specify a delimiter
                if (delimiterSpecified)
                {
                    if (usingByteEncoding)
                    {
                        Exception e =
                            new ArgumentException(FileSystemProviderStrings.DelimiterError, "delimiter");
                        WriteError(new ErrorRecord(
                            e,
                            "GetContentReaderArgumentError",
                            ErrorCategory.InvalidArgument,
                            path));
                    }
                    else
                    {
                        // Initialize the file reader
                        stream = new FileSystemContentReaderWriter(path, streamName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, delimiter, encoding, waitForChanges, this, isRawStream);
                    }
                }
                else
                {
                    stream = new FileSystemContentReaderWriter(path, streamName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, encoding, usingByteEncoding, waitForChanges, this, isRawStream);
                }
            }
            catch (PathTooLongException pathTooLong)
            {
                WriteError(new ErrorRecord(pathTooLong, "GetContentReaderPathTooLongError", ErrorCategory.InvalidArgument, path));
            }
            catch (FileNotFoundException fileNotFound)
            {
                WriteError(new ErrorRecord(fileNotFound, "GetContentReaderFileNotFoundError", ErrorCategory.ObjectNotFound, path));
            }
            catch (DirectoryNotFoundException directoryNotFound)
            {
                WriteError(new ErrorRecord(directoryNotFound, "GetContentReaderDirectoryNotFoundError", ErrorCategory.ObjectNotFound, path));
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "GetContentReaderArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "GetContentReaderIOError", ErrorCategory.ReadError, path));
            }
            catch (System.Security.SecurityException securityException)
            {
                WriteError(new ErrorRecord(securityException, "GetContentReaderSecurityError", ErrorCategory.PermissionDenied, path));
            }
            catch (UnauthorizedAccessException unauthorizedAccess)
            {
                WriteError(new ErrorRecord(unauthorizedAccess, "GetContentReaderUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }

            return stream;
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the get-content cmdlet.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <returns>
        /// An object that has properties and fields decorated with
        /// parsing attributes similar to a cmdlet class.
        /// </returns>
        public object GetContentReaderDynamicParameters(string path)
        {
            return new FileSystemContentReaderDynamicParameters(this);
        }

        /// <summary>
        /// Creates an instance of the FileSystemContentStream class, opens
        /// the specified file for writing, and returns the IContentReader interface
        /// to it.
        /// </summary>
        /// <param name="path">
        /// The path of the file to be opened for writing.
        /// </param>
        /// <returns>
        /// An IContentWriter for the specified file.
        /// </returns>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        public IContentWriter GetContentWriter(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            // If this is true, then the content will be read as bytes
            bool usingByteEncoding = false;
            bool streamTypeSpecified = false;
            Encoding encoding = Encoding.Default;
            const FileMode filemode = FileMode.OpenOrCreate;
            string streamName = null;
            bool suppressNewline = false;

            // Get the dynamic parameters
            if (DynamicParameters != null)
            {
                FileSystemContentWriterDynamicParameters dynParams =
                    DynamicParameters as FileSystemContentWriterDynamicParameters;

                if (dynParams != null)
                {
                    usingByteEncoding = dynParams.AsByteStream;
                    streamTypeSpecified = dynParams.WasStreamTypeSpecified;

                    if (usingByteEncoding && streamTypeSpecified)
                    {
                        WriteWarning(FileSystemProviderStrings.EncodingNotUsed);
                    }

                    if (streamTypeSpecified)
                    {
                        encoding = dynParams.Encoding;
                    }

#if !UNIX
                    streamName = dynParams.Stream;
#endif
                    suppressNewline = dynParams.NoNewline.IsPresent;
                }
            }

#if !UNIX
            // See if they've used the inline stream syntax. They have more than one colon.
            int firstColon = path.IndexOf(':');
            int secondColon = path.IndexOf(':', firstColon + 1);
            if (secondColon > 0)
            {
                streamName = path.Substring(secondColon + 1);
                path = path.Remove(secondColon);
            }
#endif

            FileSystemContentReaderWriter stream = null;

            try
            {
                // Add-Content and Set-Content will write a non-terminating error if the target is a directory.
                // On Windows, the streamName must be null or empty for it to write the error. Otherwise, the
                // alternate data stream is not a directory, even if it's set on a directory.
                if (Directory.Exists(path)
#if !UNIX
                    && string.IsNullOrEmpty(streamName)
#endif
                    )
                {
                    string errMsg = StringUtil.Format(SessionStateStrings.WriteContainerContentException, path);
                    ErrorRecord error = new ErrorRecord(new InvalidOperationException(errMsg), "WriteContainerContentException", ErrorCategory.InvalidOperation, null);
                    WriteError(error);
                    return stream;
                }

                stream = new FileSystemContentReaderWriter(path, streamName, filemode, FileAccess.Write, FileShare.ReadWrite, encoding, usingByteEncoding, false, this, false, suppressNewline);
            }
            catch (PathTooLongException pathTooLong)
            {
                WriteError(new ErrorRecord(pathTooLong, "GetContentWriterPathTooLongError", ErrorCategory.InvalidArgument, path));
            }
            catch (FileNotFoundException fileNotFound)
            {
                WriteError(new ErrorRecord(fileNotFound, "GetContentWriterFileNotFoundError", ErrorCategory.ObjectNotFound, path));
            }
            catch (DirectoryNotFoundException directoryNotFound)
            {
                WriteError(new ErrorRecord(directoryNotFound, "GetContentWriterDirectoryNotFoundError", ErrorCategory.ObjectNotFound, path));
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "GetContentWriterArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "GetContentWriterIOError", ErrorCategory.WriteError, path));
            }
            catch (System.Security.SecurityException securityException)
            {
                WriteError(new ErrorRecord(securityException, "GetContentWriterSecurityError", ErrorCategory.PermissionDenied, path));
            }
            catch (UnauthorizedAccessException unauthorizedAccess)
            {
                WriteError(new ErrorRecord(unauthorizedAccess, "GetContentWriterUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
            }

            return stream;
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the set-content and
        /// add-content cmdlets.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <returns>
        /// An object that has properties and fields decorated with
        /// parsing attributes similar to a cmdlet class.
        /// </returns>
        public object GetContentWriterDynamicParameters(string path)
        {
            return new FileSystemContentWriterDynamicParameters(this);
        }

        /// <summary>
        /// Clears the content of the specified file.
        /// </summary>
        /// <param name="path">
        /// The path to the file of which to clear the contents.
        /// </param>
        /// <exception cref="System.ArgumentException">
        ///     path is null or empty.
        /// </exception>
        public void ClearContent(string path)
        {
            if (string.IsNullOrEmpty(path))
            {
                throw PSTraceSource.NewArgumentException(nameof(path));
            }

            path = NormalizePath(path);

            try
            {
#if !UNIX
                bool clearStream = false;
                string streamName = null;
                FileSystemClearContentDynamicParameters dynamicParameters = null;
                FileSystemContentWriterDynamicParameters writerDynamicParameters = null;

                // We get called during:
                //     - Clear-Content
                //     - Set-Content, in the phase that clears the path first.
                if (DynamicParameters != null)
                {
                    dynamicParameters = DynamicParameters as FileSystemClearContentDynamicParameters;
                    writerDynamicParameters = DynamicParameters as FileSystemContentWriterDynamicParameters;

                    if (dynamicParameters != null)
                    {
                        if ((dynamicParameters.Stream != null) && (dynamicParameters.Stream.Length > 0))
                            clearStream = true;
                        streamName = dynamicParameters.Stream;
                    }
                    else if (writerDynamicParameters != null)
                    {
                        if ((writerDynamicParameters.Stream != null) && (writerDynamicParameters.Stream.Length > 0))
                            clearStream = true;
                        streamName = writerDynamicParameters.Stream;
                    }

                    if (string.IsNullOrEmpty(streamName))
                    {
                        // See if they've used the inline stream syntax. They have more than one colon.
                        int firstColon = path.IndexOf(':');
                        int secondColon = path.IndexOf(':', firstColon + 1);
                        if (secondColon > 0)
                        {
                            streamName = path.Substring(secondColon + 1);
                            path = path.Remove(secondColon);

                            clearStream = true;
                        }
                    }
                }

                // If they're just working on the DATA stream, don't use the Alternate Data Stream
                // utils to clear the stream - otherwise, the Win32 API will trash the other streams.
                if (string.Equals(":$DATA", streamName, StringComparison.OrdinalIgnoreCase))
                {
                    clearStream = false;
                }

#endif
                // On Windows, determine if our argument is a directory only after we determine if
                // we're being asked to work with an alternate data stream, because directories can have
                // alternate data streams on them that are not child items. These alternate data streams
                // must be treated as data streams, even if they're attached to directories. However,
                // if asked to work with a directory without a data stream specified, write a non-terminating
                // error instead of clearing all child items of the directory. (On non-Windows, alternate
                // data streams don't exist, so in that environment always write the error when addressing
                // a directory.)
                if (Directory.Exists(path)
#if !UNIX
                    && !clearStream
#endif
                    )
                {
                    string errorMsg = StringUtil.Format(SessionStateStrings.ClearDirectoryContent, path);
                    WriteError(new ErrorRecord(new NotSupportedException(errorMsg), "ClearDirectoryContent", ErrorCategory.InvalidOperation, path));
                    return;
                }
#if !UNIX
                if (clearStream)
                {
                    FileStream fileStream = null;

                    string streamAction = string.Format(
                        CultureInfo.InvariantCulture,
                        FileSystemProviderStrings.StreamAction,
                        streamName, path);
                    if (ShouldProcess(streamAction))
                    {
                        // If we've been called as part of Clear-Content, validate that the stream exists.
                        // This is because the core API doesn't support truncate mode.
                        if (dynamicParameters != null)
                        {
                            fileStream = AlternateDataStreamUtilities.CreateFileStream(path, streamName, FileMode.Open, FileAccess.Write, FileShare.Write);
                            fileStream.Dispose();
                        }

                        fileStream = AlternateDataStreamUtilities.CreateFileStream(
                            path, streamName, FileMode.Create, FileAccess.Write, FileShare.Write);
                        fileStream.Dispose();
                    }
                }
                else
#endif
                {
                    string action = FileSystemProviderStrings.ClearContentActionFile;
                    string resource = StringUtil.Format(FileSystemProviderStrings.ClearContentesourceTemplate, path);

                    if (!ShouldProcess(resource, action))
                        return;

                    FileStream fileStream = new FileStream(path, FileMode.Truncate, FileAccess.Write, FileShare.Write);
                    fileStream.Dispose();
                }

                // For filesystem once content is cleared
                WriteItemObject(string.Empty, path, false);
            }
            catch (ArgumentException argException)
            {
                WriteError(new ErrorRecord(argException, "ClearContentArgumentError", ErrorCategory.InvalidArgument, path));
            }
            catch (IOException ioException)
            {
                // IOException contains specific message about the error occurred and so no need for errordetails.
                WriteError(new ErrorRecord(ioException, "ClearContentIOError", ErrorCategory.WriteError, path));
            }
            catch (UnauthorizedAccessException accessException)
            {
                if (Force)
                {
                    //// Store the old attributes so that we can recover them
                    FileAttributes oldAttributes = File.GetAttributes(path);

                    try
                    {
                        // Since a security exception was thrown, try to mask off
                        // the hidden and readonly bits and then retry.
                        File.SetAttributes(path, (File.GetAttributes(path) & ~(FileAttributes.Hidden | FileAttributes.ReadOnly)));
                        FileStream fileStream = new FileStream(path, FileMode.Truncate, FileAccess.Write, FileShare.Write);
                        fileStream.Dispose();

                        // For filesystem once content is cleared
                        WriteItemObject(string.Empty, path, false);
                    }
                    catch (UnauthorizedAccessException failure)
                    {
                        WriteError(new ErrorRecord(failure, "RemoveFileSystemItemUnAuthorizedAccess", ErrorCategory.PermissionDenied, path));
                    }
                    finally
                    {
                        //// Reset the attributes
                        File.SetAttributes(path, oldAttributes);
                    }
                }
                else
                {
                    WriteError(new ErrorRecord(accessException, "ClearContentUnauthorizedAccessError", ErrorCategory.PermissionDenied, path));
                }
            }
        }

        /// <summary>
        /// Gets the dynamic property parameters required by the clear-content cmdlet.
        /// </summary>
        /// <param name="path">
        /// If the path was specified on the command line, this is the path
        /// to the item for which to get the dynamic parameters.
        /// </param>
        /// <returns>
        /// A FileSystemClearContentDynamicParameters that provides access to the -Stream dynamic parameter.
        /// </returns>
        public object ClearContentDynamicParameters(string path)
        {
            return new FileSystemClearContentDynamicParameters();
        }

        #endregion IContentCmdletProvider

        /// <summary>
        /// -raw is not allowed when -first,-last or -wait is specified
        /// this call will validate that and throws.
        /// </summary>
        private void ValidateParameters(bool isRawSpecified)
        {
            if (isRawSpecified)
            {
                if (this.Context.MyInvocation.BoundParameters.ContainsKey("TotalCount"))
                {
                    string message = StringUtil.Format(FileSystemProviderStrings.NoFirstLastWaitForRaw, "Raw", "TotalCount");
                    throw new PSInvalidOperationException(message);
                }

                if (this.Context.MyInvocation.BoundParameters.ContainsKey("Tail"))
                {
                    string message = StringUtil.Format(FileSystemProviderStrings.NoFirstLastWaitForRaw, "Raw", "Tail");
                    throw new PSInvalidOperationException(message);
                }

                if (this.Context.MyInvocation.BoundParameters.ContainsKey("Wait"))
                {
                    string message = StringUtil.Format(FileSystemProviderStrings.NoFirstLastWaitForRaw, "Raw", "Wait");
                    throw new PSInvalidOperationException(message);
                }

                if (this.Context.MyInvocation.BoundParameters.ContainsKey("Delimiter"))
                {
                    string message = StringUtil.Format(FileSystemProviderStrings.NoFirstLastWaitForRaw, "Raw", "Delimiter");
                    throw new PSInvalidOperationException(message);
                }
            }
        }

        /// <summary>
        /// The API 'PathIsNetworkPath' is not available in CoreSystem.
        /// This implementation is based on the 'PathIsNetworkPath' API.
        /// </summary>
        /// <param name="path"></param>
        /// <returns></returns>
        internal static bool PathIsNetworkPath(string path)
        {
#if UNIX
            return false;
#else
            return WinPathIsNetworkPath(path);
#endif
        }

#if !UNIX
        /// <summary>
        /// The API 'PathIsNetworkPath' is not available in CoreSystem.
        /// This implementation is based on the 'PathIsNetworkPath' API.
        /// </summary>
        /// <param name="path">A file system path.</param>
        /// <returns>True if the path is a network path.</returns>
        internal static bool WinPathIsNetworkPath(string path)
            {
                if (string.IsNullOrEmpty(path))
                {
                    return false;
                }

                if (Utils.PathIsUnc(path, networkOnly : true))
                {
                    return true;
                }

                if (path.Length > 1 && path[1] == ':' && char.IsAsciiLetter(path[0]))
                {
                    // path[0] is ASCII letter, e.g. is in 'A'-'Z' or 'a'-'z'.
                    int errorCode = Interop.Windows.GetUNCForNetworkDrive(path[0], out string _);

                    // From the 'IsNetDrive' API.
                    // 0: success; 1201: connection closed; 31: device error
                    if (errorCode == Interop.Windows.ERROR_SUCCESS ||
                        errorCode == Interop.Windows.ERROR_CONNECTION_UNAVAIL ||
                        errorCode == Interop.Windows.ERROR_GEN_FAILURE)
                    {
                        return true;
                    }
                }

                return false;
            }
#endif

        #region InodeTracker
        /// <summary>
        /// Tracks visited files/directories by caching their device IDs and inodes.
        /// </summary>
        private sealed class InodeTracker
        {
            private readonly HashSet<(UInt64, UInt64)> _visitations;

            /// <summary>
            /// Construct a new InodeTracker with an initial path.
            /// </summary>
            internal InodeTracker(string path)
            {
                _visitations = new HashSet<(UInt64, UInt64)>();

                if (InternalSymbolicLinkLinkCodeMethods.GetInodeData(path, out (UInt64, UInt64) inodeData))
                {
                    _visitations.Add(inodeData);
                }
            }

            /// <summary>
            /// Attempt to mark a path as having been visited.
            /// </summary>
            /// <param name="path">
            /// Path to the file system item to be visited.
            /// </param>
            /// <returns>
            /// True if the path had not been previously visited and was
            /// successfully marked as visited, false otherwise.
            /// </returns>
            internal bool TryVisitPath(string path)
            {
                bool returnValue = false;

                if (InternalSymbolicLinkLinkCodeMethods.GetInodeData(path, out (UInt64, UInt64) inodeData))
                {
                    returnValue = _visitations.Add(inodeData);
                }

                return returnValue;
            }
        }

        #endregion
    }

    internal static class SafeInvokeCommand
    {
        public static Hashtable Invoke(System.Management.Automation.PowerShell ps, FileSystemProvider fileSystemContext, CmdletProviderContext cmdletContext)
        {
            return Invoke(ps, fileSystemContext, cmdletContext, true);
        }

        public static Hashtable Invoke(System.Management.Automation.PowerShell ps, FileSystemProvider fileSystemContext, CmdletProviderContext cmdletContext, bool shouldHaveOutput)
        {
            bool useFileSystemProviderContext = (cmdletContext == null);

            if (useFileSystemProviderContext)
            {
                Dbg.Diagnostics.Assert(fileSystemContext != null, "The caller should verify FileSystemProvider context.");
            }

            Collection<Hashtable> output;
            try
            {
                output = ps.Invoke<Hashtable>();
            }
            catch (Exception e)
            {
                if (useFileSystemProviderContext)
                {
                    fileSystemContext.WriteError(new ErrorRecord(e, "CopyFileRemoteExecutionError", ErrorCategory.InvalidOperation, ps));
                    ps.Commands.Clear();
                }
                else
                {
                    cmdletContext.WriteError(new ErrorRecord(e, "CopyFileRemoteExecutionError", ErrorCategory.InvalidOperation, ps));
                    ps.Commands.Clear();
                }

                return null;
            }

            if (ps.HadErrors)
            {
                foreach (var error in ps.Streams.Error)
                {
                    if (useFileSystemProviderContext)
                    {
                        fileSystemContext.WriteError(error);
                    }
                    else
                    {
                        cmdletContext.WriteError(error);
                    }
                }
            }

            ps.Commands.Clear();

            if (shouldHaveOutput)
            {
                if (output.Count != 1 || output[0].GetType() != typeof(Hashtable))
                {
                    // unexpected output
                    Dbg.Diagnostics.Assert(output[0] != null, "Expected an output from the remote call.");
                    return null;
                }

                return (Hashtable)output[0];
            }

            return null;
        }
    }

    #endregion

    #region Dynamic Parameters

    internal sealed class CopyItemDynamicParameters
    {
        [Parameter]
        [ValidateNotNullOrEmpty]
        public PSSession FromSession { get; set; }

        [Parameter]
        [ValidateNotNullOrEmpty]
        public PSSession ToSession { get; set; }
    }

    /// <summary>
    /// Defines the container cmdlet dynamic providers.
    /// </summary>
    internal sealed class GetChildDynamicParameters
    {
        /// <summary>
        /// Gets or sets the attribute filtering enum evaluator.
        /// </summary>
        [Parameter]
        public FlagsExpression<FileAttributes> Attributes { get; set; }

        /// <summary>
        /// Gets or sets the flag to follow symbolic links when recursing.
        /// </summary>
        [Parameter]
        public SwitchParameter FollowSymlink { get; set; }

        /// <summary>
        /// Gets or sets the filter directory flag.
        /// </summary>
        [Parameter]
        [Alias("ad")]
        public SwitchParameter Directory
        {
            get { return _attributeDirectory; }

            set { _attributeDirectory = value; }
        }

        private bool _attributeDirectory;

        /// <summary>
        /// Gets or sets the filter file flag.
        /// </summary>
        [Parameter]
        [Alias("af")]
        public SwitchParameter File
        {
            get { return _attributeFile; }

            set { _attributeFile = value; }
        }

        private bool _attributeFile;

        /// <summary>
        /// Gets or sets the filter hidden flag.
        /// </summary>
        [Parameter]
        [Alias("ah", "h")]
        public SwitchParameter Hidden
        {
            get { return _attributeHidden; }

            set { _attributeHidden = value; }
        }

        private bool _attributeHidden;

        /// <summary>
        /// Gets or sets the filter readonly flag.
        /// </summary>
        [Parameter]
        [Alias("ar")]
        public SwitchParameter ReadOnly
        {
            get { return _attributeReadOnly; }

            set { _attributeReadOnly = value; }
        }

        private bool _attributeReadOnly;

        /// <summary>
        /// Gets or sets the filter system flag.
        /// </summary>
        [Parameter]
        [Alias("as")]
        public SwitchParameter System
        {
            get { return _attributeSystem; }

            set { _attributeSystem = value; }
        }

        private bool _attributeSystem;
    }

    /// <summary>
    /// Defines the dynamic parameters used by both the content reader and writer.
    /// </summary>
    public class FileSystemContentDynamicParametersBase
    {
        internal FileSystemContentDynamicParametersBase(FileSystemProvider provider)
        {
            _provider = provider;
        }

        private readonly FileSystemProvider _provider;

        /// <summary>
        /// Gets or sets the encoding method used when
        /// reading data from the file.
        /// </summary>
        [Parameter]
        [ArgumentToEncodingTransformation]
        [ArgumentEncodingCompletions]
        [ValidateNotNullOrEmpty]
        public Encoding Encoding
        {
            get
            {
                return _encoding;
            }

            set
            {
                // Check for UTF-7 by checking for code page 65000
                // See: https://learn.microsoft.com/dotnet/core/compatibility/corefx#utf-7-code-paths-are-obsolete
                if (value != null && value.CodePage == 65000)
                {
                    _provider.WriteWarning(PathUtilsStrings.Utf7EncodingObsolete);
                }
                _encoding = value;
                // If an encoding was explicitly set, be sure to capture that.
                WasStreamTypeSpecified = true;
            }
        }

        private Encoding _encoding = Encoding.Default;

        /// <summary>
        /// Return file contents as a byte stream or create file from a series of bytes.
        /// </summary>
        [Parameter]
        public SwitchParameter AsByteStream { get; set; }

#if !UNIX
        /// <summary>
        /// A parameter to return a stream of an item.
        /// </summary>
        [Parameter]
        public string Stream { get; set; }
#endif

        /// <summary>
        /// Gets the status of the StreamType parameter.  Returns true
        /// if the stream was opened with a user-specified encoding, false otherwise.
        /// </summary>
        public bool WasStreamTypeSpecified { get; private set; }
    }

    /// <summary>
    /// Defines the dynamic parameters used by the Clear-Content cmdlet.
    /// </summary>
    public class FileSystemClearContentDynamicParameters
    {
#if !UNIX
        /// <summary>
        /// A parameter to return a stream of an item.
        /// </summary>
        [Parameter]
        public string Stream { get; set; }
#endif
    }

    /// <summary>
    /// Defines the dynamic parameters used by the set-content and
    /// add-content cmdlets.
    /// </summary>
    public class FileSystemContentWriterDynamicParameters : FileSystemContentDynamicParametersBase
    {
        internal FileSystemContentWriterDynamicParameters(FileSystemProvider provider) : base(provider) { }

        /// <summary>
        /// False to add a newline to the end of the output string, true if not.
        /// </summary>
        [Parameter]
        public SwitchParameter NoNewline
        {
            get
            {
                return _suppressNewline;
            }

            set
            {
                _suppressNewline = value;
            }
        }

        private bool _suppressNewline = false;
    }

    /// <summary>
    /// Defines the dynamic parameters used by the get-content cmdlet.
    /// </summary>
    public class FileSystemContentReaderDynamicParameters : FileSystemContentDynamicParametersBase
    {
        internal FileSystemContentReaderDynamicParameters(FileSystemProvider provider) : base(provider) { }

        /// <summary>
        /// Gets or sets the delimiter to use when reading the file.  Custom delimiters
        /// may not be used when the file is opened with a "Byte" encoding.
        /// </summary>
        [Parameter]
        public string Delimiter
        {
            get
            {
                return _delimiter;
            }

            set
            {
                DelimiterSpecified = true;
                _delimiter = value;
            }
        }

        private string _delimiter = "\n";

        /// <summary>
        /// Gets or sets the Wait flag.  The wait flag determines if we want
        /// the read-content call to poll (and wait) for changes to the file,
        /// rather than exit after the content has been read.
        /// </summary>
        [Parameter]
        public SwitchParameter Wait
        {
            get
            {
                return _wait;
            }

            set
            {
                _wait = value;
            }
        }

        private bool _wait;

        /// <summary>
        /// When the Raw switch is present, we don't do any breaks on newlines,
        /// and only emit one object to the pipeline: all of the content.
        /// </summary>
        [Parameter]
        public SwitchParameter Raw
        {
            get
            {
                return _isRaw;
            }

            set
            {
                _isRaw = value;
            }
        }

        private bool _isRaw;

        /// <summary>
        /// Gets the status of the delimiter parameter.  Returns true
        /// if the delimiter was explicitly specified by the user, false otherwise.
        /// </summary>
        public bool DelimiterSpecified
        {
            get; private set;
            // get
        }
    }

    /// <summary>
    /// Provides the dynamic parameters for test-path on the file system.
    /// </summary>
    public class FileSystemItemProviderDynamicParameters
    {
        /// <summary>
        /// A parameter to test if a file is older than a certain time or date.
        /// </summary>
        [Parameter]
        public DateTime? OlderThan { get; set; }

        /// <summary>
        /// A parameter to test if a file is newer than a certain time or date.
        /// </summary>
        [Parameter]
        public DateTime? NewerThan { get; set; }
    }

    /// <summary>
    /// Provides the dynamic parameters for Get-Item on the file system.
    /// </summary>
    public class FileSystemProviderGetItemDynamicParameters
    {
#if !UNIX
        /// <summary>
        /// A parameter to return the streams of an item.
        /// </summary>
        [Parameter]
        [ValidateNotNullOrEmpty()]
        [SuppressMessage("Microsoft.Performance", "CA1819:PropertiesShouldNotReturnArrays")]
        public string[] Stream { get; set; }
#endif
    }

    /// <summary>
    /// Provides the dynamic parameters for Remove-Item on the file system.
    /// </summary>
    public class FileSystemProviderRemoveItemDynamicParameters
    {
#if !UNIX
        /// <summary>
        /// A parameter to return the streams of an item.
        /// </summary>
        [Parameter]
        [ValidateNotNullOrEmpty()]
        [SuppressMessage("Microsoft.Performance", "CA1819:PropertiesShouldNotReturnArrays")]
        public string[] Stream { get; set; }
#endif
    }

    #endregion

    #region Symbolic Link

    /// <summary>
    /// Class to find the symbolic link target.
    /// </summary>
    public static partial class InternalSymbolicLinkLinkCodeMethods
    {
        private const int FSCTL_GET_REPARSE_POINT = 0x000900A8;

        private const int FSCTL_SET_REPARSE_POINT = 0x000900A4;

        private const int FSCTL_DELETE_REPARSE_POINT = 0x000900AC;

        private const uint IO_REPARSE_TAG_SYMLINK = 0xA000000C;

        private const uint IO_REPARSE_TAG_MOUNT_POINT = 0xA0000003;

        private const uint IO_REPARSE_TAG_APPEXECLINK = 0x8000001B;

        private const string NonInterpretedPathPrefix = @"\??\";

        [StructLayout(LayoutKind.Sequential)]
        private struct REPARSE_DATA_BUFFER_SYMBOLICLINK
        {
            public uint ReparseTag;
            public ushort ReparseDataLength;
            public ushort Reserved;
            public ushort SubstituteNameOffset;
            public ushort SubstituteNameLength;
            public ushort PrintNameOffset;
            public ushort PrintNameLength;
            public uint Flags;

            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x3FF0)]
            public byte[] PathBuffer;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct REPARSE_DATA_BUFFER_MOUNTPOINT
        {
            public uint ReparseTag;
            public ushort ReparseDataLength;
            public ushort Reserved;
            public ushort SubstituteNameOffset;
            public ushort SubstituteNameLength;
            public ushort PrintNameOffset;
            public ushort PrintNameLength;

            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x3FF0)]
            public byte[] PathBuffer;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct BY_HANDLE_FILE_INFORMATION
        {
            public uint FileAttributes;
            public FILE_TIME CreationTime;
            public FILE_TIME LastAccessTime;
            public FILE_TIME LastWriteTime;
            public uint VolumeSerialNumber;
            public uint FileSizeHigh;
            public uint FileSizeLow;
            public uint NumberOfLinks;
            public uint FileIndexHigh;
            public uint FileIndexLow;
        }

        internal struct FILE_TIME
        {
            public uint dwLowDateTime;
            public uint dwHighDateTime;
        }

        [LibraryImport(PinvokeDllNames.DeviceIoControlDllName, StringMarshalling = StringMarshalling.Utf16, SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static partial bool DeviceIoControl(IntPtr hDevice, uint dwIoControlCode,
            IntPtr InBuffer, int nInBufferSize,
            IntPtr OutBuffer, int nOutBufferSize,
            out int pBytesReturned, IntPtr lpOverlapped);

        [LibraryImport(PinvokeDllNames.GetFileInformationByHandleDllName)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static partial bool GetFileInformationByHandle(
                IntPtr hFile,
                out BY_HANDLE_FILE_INFORMATION lpFileInformation);

        /// <summary>
        /// Gets the target of the specified reparse point.
        /// </summary>
        /// <param name="instance">The object of FileInfo or DirectoryInfo type.</param>
        /// <returns>The target of the reparse point.</returns>
        [Obsolete("This method is now obsolete. Please use the .NET API 'FileSystemInfo.LinkTarget'", error: true)]
        public static string GetTarget(PSObject instance)
        {
            if (instance.BaseObject is FileSystemInfo fileSysInfo)
            {
                if (!fileSysInfo.Exists)
                {
                    throw new ArgumentException(
                        StringUtil.Format(SessionStateStrings.PathNotFound, fileSysInfo.FullName));
                }

                return fileSysInfo.LinkTarget;
            }

            return null;
        }

        /// <summary>
        /// Gets the target for a given file or directory, resolving symbolic links.
        /// </summary>
        /// <param name="instance">The FileInfo or DirectoryInfo type.</param>
        /// <returns>The file path the instance points to.</returns>
        public static string ResolvedTarget(PSObject instance)
        {
            if (instance.BaseObject is FileSystemInfo fileSysInfo)
            {
                FileSystemInfo linkTarget = fileSysInfo.ResolveLinkTarget(true);
                return linkTarget is null ? fileSysInfo.FullName : linkTarget.FullName;
            }

            return null;
        }

        /// <summary>
        /// Gets the link type of the specified reparse point.
        /// </summary>
        /// <param name="instance">The object of FileInfo or DirectoryInfo type.</param>
        /// <returns>The link type of the reparse point. SymbolicLink for symbolic links.</returns>
        public static string GetLinkType(PSObject instance)
        {
            FileSystemInfo fileSysInfo = instance.BaseObject as FileSystemInfo;

            if (fileSysInfo != null)
            {
                return InternalGetLinkType(fileSysInfo);
            }

            return null;
        }

        private static string InternalGetLinkType(FileSystemInfo fileInfo)
        {
#if UNIX
            return Platform.NonWindowsInternalGetLinkType(fileInfo);
#else
            return WinInternalGetLinkType(fileInfo.FullName);
#endif
        }

#if !UNIX
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2001:AvoidCallingProblematicMethods")]
        private static string WinInternalGetLinkType(string filePath)
        {
            // We set accessMode parameter to zero because documentation says:
            // If this parameter is zero, the application can query certain metadata
            // such as file, directory, or device attributes without accessing
            // that file or device, even if GENERIC_READ access would have been denied.
            using (SafeFileHandle handle = WinOpenReparsePoint(filePath, (FileAccess)0))
            {
                int outBufferSize = Marshal.SizeOf<REPARSE_DATA_BUFFER_SYMBOLICLINK>();

                IntPtr outBuffer = Marshal.AllocHGlobal(outBufferSize);
                bool success = false;

                try
                {
                    int bytesReturned;
                    string linkType = null;

                    // OACR warning 62001 about using DeviceIOControl has been disabled.
                    // According to MSDN guidance DangerousAddRef() and DangerousRelease() have been used.
                    handle.DangerousAddRef(ref success);

                    // Get Buffer size
                    IntPtr dangerousHandle = handle.DangerousGetHandle();

                    bool result = DeviceIoControl(
                        dangerousHandle,
                        FSCTL_GET_REPARSE_POINT,
                        InBuffer: IntPtr.Zero,
                        nInBufferSize: 0,
                        outBuffer,
                        outBufferSize,
                        out bytesReturned,
                        lpOverlapped: IntPtr.Zero);

                    if (!result)
                    {
                        // It's not a reparse point or the file system doesn't support reparse points.
                        return WinIsHardLink(ref dangerousHandle) ? "HardLink" : null;
                    }

                    REPARSE_DATA_BUFFER_SYMBOLICLINK reparseDataBuffer = Marshal.PtrToStructure<REPARSE_DATA_BUFFER_SYMBOLICLINK>(outBuffer);

                    switch (reparseDataBuffer.ReparseTag)
                    {
                        case IO_REPARSE_TAG_SYMLINK:
                            linkType = "SymbolicLink";
                            break;

                        case IO_REPARSE_TAG_MOUNT_POINT:
                            linkType = "Junction";
                            break;

                        default:
                            linkType = null;
                            break;
                    }

                    return linkType;
                }
                finally
                {
                    if (success)
                    {
                        handle.DangerousRelease();
                    }

                    Marshal.FreeHGlobal(outBuffer);
                }
            }
        }
#endif

        internal static bool IsHardLink(FileSystemInfo fileInfo)
        {
#if UNIX
            return Platform.NonWindowsIsHardLink(fileInfo);
#else
            bool isHardLink = false;

            // only check for hard link if the item is not directory
            if ((fileInfo.Attributes & System.IO.FileAttributes.Directory) != System.IO.FileAttributes.Directory)
            {
                SafeFileHandle handle = Interop.Windows.CreateFileWithSafeFileHandle(fileInfo.FullName, FileAccess.Read, FileShare.Read, FileMode.Open, Interop.Windows.FileAttributes.Normal);

                using (handle)
                {
                    var dangerousHandle = handle.DangerousGetHandle();
                    isHardLink = InternalSymbolicLinkLinkCodeMethods.WinIsHardLink(ref dangerousHandle);
                }
            }

            return isHardLink;
#endif
        }

        internal static bool IsReparsePoint(FileSystemInfo fileInfo)
        {
            return fileInfo.Attributes.HasFlag(System.IO.FileAttributes.ReparsePoint);
        }

        internal static bool IsReparsePointLikeSymlink(FileSystemInfo fileInfo)
        {
#if UNIX
            // Reparse point on Unix is a symlink.
            return IsReparsePoint(fileInfo);
#else
            if (InternalTestHooks.OneDriveTestOn && fileInfo.Name == InternalTestHooks.OneDriveTestSymlinkName)
            {
                return !InternalTestHooks.OneDriveTestRecurseOn;
            }

            Interop.Windows.WIN32_FIND_DATA data = default;
            using (Interop.Windows.SafeFindHandle handle = Interop.Windows.FindFirstFile(fileInfo.FullName, ref data))
            {
                if (handle.IsInvalid)
                {
                    // Our handle could be invalidated by something else touching the filesystem,
                    // so ensure we deal with that possibility here
                    int lastError = Marshal.GetLastWin32Error();
                    throw new Win32Exception(lastError);
                }

                // We already have the file attribute information from our Win32 call,
                // so no need to take the expense of the FileInfo.FileAttributes call
                const int FILE_ATTRIBUTE_REPARSE_POINT = 0x0400;
                if ((data.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) == 0)
                {
                    // Not a reparse point.
                    return false;
                }

                // The name surrogate bit 0x20000000 is defined in https://learn.microsoft.com/windows/win32/fileio/reparse-point-tags
                // Name surrogates (0x20000000) are reparse points that point to other named entities local to the filesystem
                // (like symlinks and mount points).
                // In the case of OneDrive, they are not name surrogates and would be safe to recurse into.
                if ((data.dwReserved0 & 0x20000000) == 0 && (data.dwReserved0 != IO_REPARSE_TAG_APPEXECLINK))
                {
                    return false;
                }
            }

            return true;
#endif
        }

        internal static bool IsSameFileSystemItem(string pathOne, string pathTwo)
        {
#if UNIX
            return Platform.NonWindowsIsSameFileSystemItem(pathOne, pathTwo);
#else
            return WinIsSameFileSystemItem(pathOne, pathTwo);
#endif
        }

#if !UNIX
        private static bool WinIsSameFileSystemItem(string pathOne, string pathTwo)
        {
            const Interop.Windows.FileAttributes Attributes = Interop.Windows.FileAttributes.BackupSemantics | Interop.Windows.FileAttributes.PosixSemantics;

            using (var sfOne = Interop.Windows.CreateFileWithSafeFileHandle(pathOne, FileAccess.Read, FileShare.Read, FileMode.Open, Attributes))
            using (var sfTwo = Interop.Windows.CreateFileWithSafeFileHandle(pathTwo, FileAccess.Read, FileShare.Read, FileMode.Open, Attributes))
            {
                if (!sfOne.IsInvalid && !sfTwo.IsInvalid)
                {
                    BY_HANDLE_FILE_INFORMATION infoOne;
                    BY_HANDLE_FILE_INFORMATION infoTwo;
                    if (GetFileInformationByHandle(sfOne.DangerousGetHandle(), out infoOne)
                        && GetFileInformationByHandle(sfTwo.DangerousGetHandle(), out infoTwo))
                    {
                        return infoOne.VolumeSerialNumber == infoTwo.VolumeSerialNumber
                               && infoOne.FileIndexHigh == infoTwo.FileIndexHigh
                               && infoOne.FileIndexLow == infoTwo.FileIndexLow;
                    }
                }
            }

            return false;
        }
#endif

        internal static bool GetInodeData(string path, out System.ValueTuple<UInt64, UInt64> inodeData)
        {
#if UNIX
            bool rv = Platform.NonWindowsGetInodeData(path, out inodeData);
#else
            bool rv = WinGetInodeData(path, out inodeData);
#endif
            return rv;
        }

#if !UNIX
        private static bool WinGetInodeData(string path, out System.ValueTuple<UInt64, UInt64> inodeData)
        {
            const Interop.Windows.FileAttributes Attributes = Interop.Windows.FileAttributes.BackupSemantics | Interop.Windows.FileAttributes.PosixSemantics;

            using (var sf = Interop.Windows.CreateFileWithSafeFileHandle(path, FileAccess.Read, FileShare.Read, FileMode.Open, Attributes))
            {
                if (!sf.IsInvalid)
                {
                    BY_HANDLE_FILE_INFORMATION info;

                    if (GetFileInformationByHandle(sf.DangerousGetHandle(), out info))
                    {
                        UInt64 tmp = info.FileIndexHigh;
                        tmp = (tmp << 32) | info.FileIndexLow;

                        inodeData = (info.VolumeSerialNumber, tmp);

                        return true;
                    }
                }
            }

            inodeData = (0, 0);

            return false;
        }
#endif

        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2001:AvoidCallingProblematicMethods")]
        internal static bool WinIsHardLink(ref IntPtr handle)
        {
            BY_HANDLE_FILE_INFORMATION handleInfo;
            bool succeeded = InternalSymbolicLinkLinkCodeMethods.GetFileInformationByHandle(handle, out handleInfo);
            return succeeded && (handleInfo.NumberOfLinks > 1);
        }

        internal static bool CreateJunction(string path, string target)
        {
#if UNIX
            return false;
#else
            ArgumentException.ThrowIfNullOrEmpty(path);
            ArgumentException.ThrowIfNullOrEmpty(target);

            using (SafeHandle handle = WinOpenReparsePoint(path, FileAccess.Write))
            {
                byte[] mountPointBytes = Encoding.Unicode.GetBytes(NonInterpretedPathPrefix + Path.GetFullPath(target));

                var mountPoint = new REPARSE_DATA_BUFFER_MOUNTPOINT();
                mountPoint.ReparseTag = IO_REPARSE_TAG_MOUNT_POINT;
                mountPoint.ReparseDataLength = (ushort)(mountPointBytes.Length + 12); // Added space for the header and null endo
                mountPoint.SubstituteNameOffset = 0;
                mountPoint.SubstituteNameLength = (ushort)mountPointBytes.Length;
                mountPoint.PrintNameOffset = (ushort)(mountPointBytes.Length + 2); // 2 as unicode null take 2 bytes.
                mountPoint.PrintNameLength = 0;
                mountPoint.PathBuffer = new byte[0x3FF0]; // Buffer for max size.
                Array.Copy(mountPointBytes, mountPoint.PathBuffer, mountPointBytes.Length);

                int nativeBufferSize = Marshal.SizeOf(mountPoint);
                IntPtr nativeBuffer = Marshal.AllocHGlobal(nativeBufferSize);
                bool success = false;

                try
                {
                    Marshal.StructureToPtr(mountPoint, nativeBuffer, false);

                    int bytesReturned = 0;

                    // OACR warning 62001 about using DeviceIOControl has been disabled.
                    // According to MSDN guidance DangerousAddRef() and DangerousRelease() have been used.
                    handle.DangerousAddRef(ref success);

                    bool result = DeviceIoControl(handle.DangerousGetHandle(), FSCTL_SET_REPARSE_POINT, nativeBuffer, mountPointBytes.Length + 20, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);

                    if (!result)
                    {
                        throw new Win32Exception(Marshal.GetLastWin32Error());
                    }

                    return result;
                }
                finally
                {
                    Marshal.FreeHGlobal(nativeBuffer);

                    if (success)
                    {
                        handle.DangerousRelease();
                    }
                }
            }
#endif
        }

#if !UNIX
        private static SafeFileHandle WinOpenReparsePoint(string reparsePoint, FileAccess accessMode)
        {
            const Interop.Windows.FileAttributes Attributes = Interop.Windows.FileAttributes.BackupSemantics | Interop.Windows.FileAttributes.OpenReparsePoint;

            SafeFileHandle reparsePointHandle = Interop.Windows.CreateFileWithSafeFileHandle(reparsePoint, accessMode, FileShare.ReadWrite | FileShare.Delete, FileMode.Open, Attributes);

            if (reparsePointHandle.IsInvalid)
            {
                // Save last error since Dispose() will do another pinvoke.
                int lastError = Marshal.GetLastPInvokeError();
                reparsePointHandle.Dispose();
                throw new Win32Exception(lastError);
            }

            return reparsePointHandle;
        }
#endif
    }

    #endregion
}

namespace System.Management.Automation.Internal
{
#if !UNIX
    #region AlternateDataStreamUtilities

    /// <summary>
    /// Represents alternate stream data retrieved from a file.
    /// </summary>
    public class AlternateStreamData
    {
        /// <summary>
        /// The name of the file that holds this stream.
        /// </summary>
        public string FileName { get; set; }

        /// <summary>
        /// The name of this stream.
        /// </summary>
        public string Stream { get; set; }

        /// <summary>
        /// The length of this stream.
        /// </summary>
        public long Length { get; set; }
    }

    /// <summary>
    /// Provides access to alternate data streams on a file.
    /// </summary>
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.MSInternal", "CA903:InternalNamespaceShouldNotContainPublicTypes",
        Justification = "Needed by both the FileSystem provider and Unblock-File cmdlet.")]
    public static partial class AlternateDataStreamUtilities
    {
        /// <summary>
        /// List all of the streams on a file.
        /// </summary>
        /// <param name="path">The fully-qualified path to the file.</param>
        /// <returns>The list of streams (and their size) in the file.</returns>
        internal static List<AlternateStreamData> GetStreams(string path)
        {
            ArgumentNullException.ThrowIfNull(path);

            List<AlternateStreamData> alternateStreams = new List<AlternateStreamData>();

            AlternateStreamNativeData findStreamData = new AlternateStreamNativeData();

            SafeFindHandle handle = NativeMethods.FindFirstStreamW(
                path, NativeMethods.StreamInfoLevels.FindStreamInfoStandard,
                findStreamData, 0);

            if (handle.IsInvalid)
            {
                int error = Marshal.GetLastWin32Error();

                // Directories don't normally have alternate streams, so this is not an exceptional state.
                // If a directory has no alternate data streams, FindFirstStreamW returns ERROR_HANDLE_EOF.
                // If the file system (such as FAT32) does not support alternate streams, then
                // ERROR_INVALID_PARAMETER is returned by FindFirstStreamW. See documentation:
                // https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-findfirststreamw
                if (error == NativeMethods.ERROR_HANDLE_EOF || error == NativeMethods.ERROR_INVALID_PARAMETER)
                {
                    return alternateStreams;
                }

                // An unexpected error was returned, that we don't know how to interpret. The most helpful
                // thing we can do at this point is simply throw the raw Win32 exception.
                throw new Win32Exception(error);
            }

            try
            {
                do
                {
                    // Remove the leading ':'
                    findStreamData.Name = findStreamData.Name.Substring(1);

                    // And trailing :$DATA (as long as it's not the default data stream)
                    const string dataStream = ":$DATA";
                    if (!string.Equals(findStreamData.Name, dataStream, StringComparison.OrdinalIgnoreCase))
                    {
                        findStreamData.Name = findStreamData.Name.Replace(dataStream, string.Empty);
                    }

                    AlternateStreamData data = new AlternateStreamData();
                    data.Stream = findStreamData.Name;
                    data.Length = findStreamData.Length;
                    data.FileName = path;

                    alternateStreams.Add(data);
                    findStreamData = new AlternateStreamNativeData();
                }
                while (NativeMethods.FindNextStreamW(handle, findStreamData));

                int lastError = Marshal.GetLastWin32Error();
                if (lastError != NativeMethods.ERROR_HANDLE_EOF)
                {
                    throw new Win32Exception(lastError);
                }
            }
            finally { handle.Dispose(); }

            return alternateStreams;
        }

        /// <summary>
        /// Creates a file stream on a file.
        /// </summary>
        /// <param name="path">The fully-qualified path to the file.</param>
        /// <param name="streamName">The name of the alternate data stream to open.</param>
        /// <param name="mode">The FileMode of the file.</param>
        /// <param name="access">The FileAccess of the file.</param>
        /// <param name="share">The FileShare of the file.</param>
        /// <returns>A FileStream that can be used to interact with the file.</returns>
        internal static FileStream CreateFileStream(string path, string streamName, FileMode mode, FileAccess access, FileShare share)
        {
            if (!TryCreateFileStream(path, streamName, mode, access, share, out var stream))
            {
                string errorMessage = StringUtil.Format(
                    FileSystemProviderStrings.AlternateDataStreamNotFound, streamName, path);
                throw new FileNotFoundException(errorMessage, $"{path}:{streamName}");
            }

            return stream;
        }

        /// <summary>
        /// Tries to create a file stream on a file.
        /// </summary>
        /// <param name="path">The fully-qualified path to the file.</param>
        /// <param name="streamName">The name of the alternate data stream to open.</param>
        /// <param name="mode">The FileMode of the file.</param>
        /// <param name="access">The FileAccess of the file.</param>
        /// <param name="share">The FileShare of the file.</param>
        /// <param name="stream">A FileStream that can be used to interact with the file.</param>
        /// <returns>True if the stream was successfully created, otherwise false.</returns>
        internal static bool TryCreateFileStream(string path, string streamName, FileMode mode, FileAccess access, FileShare share, out FileStream stream)
        {
            ArgumentNullException.ThrowIfNull(path);

            ArgumentNullException.ThrowIfNull(streamName);

            if (mode == FileMode.Append)
            {
                mode = FileMode.OpenOrCreate;
            }

            var resultPath = $"{path}:{streamName}";
            SafeFileHandle handle = NativeMethods.CreateFile(resultPath, access, share, IntPtr.Zero, mode, 0, IntPtr.Zero);

            if (handle.IsInvalid)
            {
                stream = null;
                return false;
            }

            stream = new FileStream(handle, access);
            return true;
        }

        /// <summary>
        /// Removes an alternate data stream.
        /// </summary>
        /// <param name="path">The path to the file.</param>
        /// <param name="streamName">The name of the alternate data stream to delete.</param>
        internal static void DeleteFileStream(string path, string streamName)
        {
            ArgumentNullException.ThrowIfNull(path);

            ArgumentNullException.ThrowIfNull(streamName);

            string adjustedStreamName = streamName.Trim();
            if (adjustedStreamName.IndexOf(':') != 0)
            {
                adjustedStreamName = ":" + adjustedStreamName;
            }

            string resultPath = path + adjustedStreamName;

            File.Delete(resultPath);
        }

        internal static void SetZoneOfOrigin(string path, SecurityZone securityZone)
        {
            using (FileStream fileStream = CreateFileStream(path, "Zone.Identifier", FileMode.Create, FileAccess.Write, FileShare.None))
            using (TextWriter textWriter = new StreamWriter(fileStream, Encoding.Unicode))
            {
                textWriter.WriteLine("[ZoneTransfer]");
                textWriter.WriteLine("ZoneId={0}", (int)securityZone);
            }

            // an alternative is to use IAttachmentExecute interface as described here:
            // http://joco.name/2010/12/22/windows-antivirus-api-in-net-and-a-com-interop-crash-course/
            // the code above seems cleaner and more robust than the IAttachmentExecute approach
        }

        internal static partial class NativeMethods
        {
            internal const int ERROR_HANDLE_EOF = 38;
            internal const int ERROR_INVALID_PARAMETER = 87;

            internal enum StreamInfoLevels { FindStreamInfoStandard = 0 }

            [LibraryImport(PinvokeDllNames.CreateFileDllName, EntryPoint = "CreateFileW", SetLastError = true, StringMarshalling = StringMarshalling.Utf16)]
            internal static partial SafeFileHandle CreateFile(string lpFileName,
                FileAccess dwDesiredAccess, FileShare dwShareMode,
                IntPtr lpSecurityAttributes, FileMode dwCreationDisposition,
                int dwFlagsAndAttributes, IntPtr hTemplateFile);

            [DllImport("kernel32.dll", ExactSpelling = true, CharSet = CharSet.Unicode, SetLastError = true)]
            [SuppressMessage("Microsoft.Globalization", "CA2101:SpecifyMarshalingForPInvokeStringArguments", MessageId = "AlternateStreamNativeData.Name")]
            internal static extern SafeFindHandle FindFirstStreamW(
                string lpFileName, StreamInfoLevels InfoLevel,
                [In, Out, MarshalAs(UnmanagedType.LPStruct)]
                AlternateStreamNativeData lpFindStreamData, uint dwFlags);

            [DllImport("kernel32.dll", ExactSpelling = true, CharSet = CharSet.Unicode, SetLastError = true)]
            [return: MarshalAs(UnmanagedType.Bool)]
            [SuppressMessage("Microsoft.Globalization", "CA2101:SpecifyMarshalingForPInvokeStringArguments", MessageId = "AlternateStreamNativeData.Name")]
            internal static extern bool FindNextStreamW(
                SafeFindHandle hndFindFile,
                [In, Out, MarshalAs(UnmanagedType.LPStruct)]
                AlternateStreamNativeData lpFindStreamData);
        }

        internal sealed partial class SafeFindHandle : SafeHandleZeroOrMinusOneIsInvalid
        {
            private SafeFindHandle() : base(true) { }

            protected override bool ReleaseHandle()
            {
                return FindClose(this.handle);
            }

            [LibraryImport(PinvokeDllNames.FindCloseDllName)]
            [return: MarshalAs(UnmanagedType.Bool)]
            private static partial bool FindClose(IntPtr handle);
        }

        /// <summary>
        /// Represents alternate stream data retrieved from a file.
        /// </summary>
        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
        internal class AlternateStreamNativeData
        {
            /// <summary>
            /// The length of this stream.
            /// </summary>
            public long Length;

            /// <summary>
            /// The name of this stream.
            /// </summary>
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 296)]
            public string Name;
        }
    }

    #endregion
#endif

    #region CopyFileFromRemoteUtils

    internal static class CopyFileRemoteUtils
    {
        private const string functionToken = "function ";
        private const string nameToken = "Name";
        private const string definitionToken = "Definition";

        #region PSCopyToSessionHelper

        internal const string PSCopyToSessionHelperName = @"PSCopyToSessionHelper";

        private static readonly string s_driveMaxSizeErrorFormatString = FileSystemProviderStrings.DriveMaxSizeError;
        private static readonly string s_PSCopyToSessionHelperDefinition = StringUtil.Format(PSCopyToSessionHelperDefinitionFormat, @"[ValidateNotNullOrEmpty()]", s_driveMaxSizeErrorFormatString);
        private static readonly string s_PSCopyToSessionHelperDefinitionRestricted = StringUtil.Format(PSCopyToSessionHelperDefinitionFormat, @"[ValidateUserDrive()]", s_driveMaxSizeErrorFormatString);

        private const string PSCopyToSessionHelperDefinitionFormat = @"
        param (
            [Parameter(ParameterSetName=""PSCopyFileToRemoteSession"")]
            [Parameter(ParameterSetName=""PSCopyAlternateStreamToRemoteSession"")]
            {0}

            [string] $copyToFilePath,

            [Parameter(ParameterSetName=""PSCopyFileToRemoteSession"", Mandatory=$false)]
            [Parameter(ParameterSetName=""PSCopyAlternateStreamToRemoteSession"")]
            [ValidateNotNullOrEmpty()]
            [string] $b64Fragment,

            [Parameter(ParameterSetName=""PSCopyFileToRemoteSession"")]
            [switch] $createFile = $false,

            [Parameter(ParameterSetName=""PSCopyFileToRemoteSession"")]
            [switch] $emptyFile = $false,

            [Parameter(ParameterSetName=""PSCopyAlternateStreamToRemoteSession"", Mandatory=$true)]
            [ValidateNotNullOrEmpty()]
            [string] $streamName,

            [Parameter(ParameterSetName=""PSTargetSupportsAlternateStreams"", Mandatory=$true)]
            {0}

            [string] $supportAltStreamPath,

            [Parameter(ParameterSetName=""PSSetFileMetadata"", Mandatory=$true)]
            {0}

            [string] $metaDataFilePath,

            [Parameter(ParameterSetName=""PSSetFileMetadata"", Mandatory=$true)]
            [ValidateNotNull()]
            [hashtable] $metaDataToSet,

            [Parameter(ParameterSetName=""PSRemoteDestinationPathIsFile"", Mandatory=$true)]
            {0}

            [string] $isFilePath,

            [Parameter(ParameterSetName=""PSGetRemotePathInfo"", Mandatory=$true)]
            {0}

            [string] $remotePath,

            [Parameter(ParameterSetName=""PSCreateDirectoryOnRemoteSession"", Mandatory=$true)]
            {0}

            [string] $createDirectoryPath,

            [Parameter(ParameterSetName=""PSCreateDirectoryOnRemoteSession"")]
            [switch] $force
        )

        # Checks if path drive specifies max size and if max size is exceeded
        #
        function CheckPSDriveSize
        {{
            param (
                [System.Management.Automation.PathInfo] $resolvedPath,
                [int] $fragmentLength
            )

            if (($null -ne $resolvedPath.Drive) -and ($null -ne $resolvedPath.Drive.MaximumSize))
            {{
                $maxUserSize = $resolvedPath.Drive.MaximumSize
                $dirSize = 0
                Microsoft.PowerShell.Management\Get-ChildItem -LiteralPath ($resolvedPath.Drive.Name + "":"") -Recurse | ForEach-Object {{
                    Microsoft.PowerShell.Management\Get-Item -LiteralPath $_.FullName -Stream * | ForEach-Object {{ $dirSize += $_.Length }}
                }}

                if (($dirSize + $fragmentLength) -gt $maxUserSize)
                {{
                    $msg = ""{1}"" -f $maxUserSize
                    throw $msg
                }}
            }}
        }}

        # Return a hashtable with the following members:
        #    BytesWritten - the number of bytes written to a file
        #
        function PSCopyFileToRemoteSession
        {{
            param(
                [string] $copyToFilePath,
                [string] $b64Fragment,
                [switch] $createFile = $false,
                [switch] $emptyFile = $false
            )

            $op = @{{
                BytesWritten = $null
            }}

            $wstream = $null

            try
            {{
                $filePathExists = Microsoft.PowerShell.Management\Test-Path -Path $copyToFilePath

                if ($createFile -or (! $filePathExists))
                {{
                    # If the file already exists, try to delete it.
                    if ($filePathExists)
                    {{
                        Microsoft.PowerShell.Management\Remove-Item -Path $copyToFilePath -Force -ea SilentlyContinue
                    }}

                    # Create the new file.
                    $fileInfo = Microsoft.PowerShell.Management\New-Item -Path $copyToFilePath -Type File -Force

                    if ($emptyFile)
                    {{
                        # Handle the empty file scenario.
                        $op['BytesWritten'] = 0
                        return $op
                    }}
                }}

                # Resolve path in case it is a PSDrive
                $resolvedPath = Microsoft.PowerShell.Management\Resolve-Path -literal $copyToFilePath

                # Decode
                $fragment = [System.Convert]::FromBase64String($b64Fragment)

                # Check if drive specifies max size and if max size is exceeded
                CheckPSDriveSize $resolvedPath $fragment.Length

                # Write fragment
                $wstream = Microsoft.PowerShell.Utility\New-Object -TypeName IO.FileStream -ArgumentList ($resolvedPath.ProviderPath), ([System.IO.FileMode]::Append)
                $wstream.Write($fragment, 0, $fragment.Length)

                $op['BytesWritten'] = $fragment.Length
            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}
            finally
            {{
                if ($null -ne $wstream)
                {{
                    $wstream.Dispose()
                }}
            }}

            return $op
        }}

        # Returns a hashtable with the following members:
        #    BytesWritten - number of bytes written to an alternate file stream
        #
        function PSCopyFileAlternateStreamToRemoteSession
        {{
            param (
                [string] $copyToFilePath,
                [string] $b64Fragment,
                [string] $streamName
            )

            $op = @{{
                BytesWritten = $null
            }}

            try
            {{
                # Resolve path in case it is a PSDrive
                $resolvedPath = Microsoft.PowerShell.Management\Resolve-Path -literal $copyToFilePath

                # Decode
                $fragment = [System.Convert]::FromBase64String($b64Fragment)

                # Check if drive specifies max size and if max size is exceeded
                CheckPSDriveSize $resolvedPath $fragment.Length

                # Write the stream
                Microsoft.PowerShell.Management\Add-Content -Path ($resolvedPath.ProviderPath) -Value $fragment -Encoding Byte -Stream $streamName -ErrorAction Stop
                $op['BytesWritten'] = $fragment.Length
            }}
            catch
            {{
                Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
            }}

            return $op
        }}

        # Returns a hashtable with the following member:
        #    TargetSupportsAlternateStreams - boolean to keep track of whether the target supports Alternate data streams.
        #
        function PSTargetSupportsAlternateStreams
        {{
            param (
                [string] $supportAltStreamPath
            )

            $result = @{{
                TargetSupportsAlternateStreams = $false
            }}

            # Resolve path in case it is a PSDrive
            $resolvedPath = Microsoft.PowerShell.Management\Resolve-Path -literal $supportAltStreamPath

            $targetDrive = [IO.Path]::GetPathRoot($resolvedPath.ProviderPath)
            if (-not $targetDrive)
            {{
                return $result
            }}

            # Check if the target drive is NTFS
            $driveFormat = 'NTFS'
            foreach ($drive in [System.IO.DriveInfo]::GetDrives())
            {{
                if (($drive.Name -eq $targetDrive) -and ($drive.DriveFormat -eq $driveFormat))
                {{
                    # Now, check if the target supports Add-Command -Stream. This functionality was introduced in version 3.0.
                    $addContentCmdlet = Microsoft.PowerShell.Core\Get-Command Microsoft.PowerShell.Management\Add-Content -ErrorAction SilentlyContinue
                    if ($addContentCmdlet.Parameters.Keys -contains 'Stream')
                    {{
                        $result['TargetSupportsAlternateStreams'] = $true
                        break
                    }}
                }}
            }}

            return $result
        }}

        # Sets the metadata for the given file.
        #
        function PSSetFileMetadata
        {{
            param (
                [string] $metaDataFilePath,
                [hashtable] $metaDataToSet
            )

            $item = Microsoft.PowerShell.Management\get-item $metaDataFilePath -ea SilentlyContinue -Force

            if ($item)
            {{
                # LastWriteTime
                if ($metaDataToSet['LastWriteTimeUtc'])
                {{
                    $item.LastWriteTimeUtc = $metaDataToSet['LastWriteTimeUtc']
                }}

                if ($metaDataToSet['LastWriteTime'])
                {{
                    $item.LastWriteTime = $metaDataToSet['LastWriteTime']
                }}

                # Attributes
                if ($metaDataToSet['Attributes'])
                {{
                    $item.Attributes = $metaDataToSet['Attributes']
                }}
            }}
        }}

        # Returns a hashtable with the following member:
        #    IsFileInfo - boolean to keep track of whether the given path is a remote file.
        #    IsDirectoryInfo - boolean to keep track of whether the given path is a remote directory.
        #    ParentIsDirectoryInfo - boolean to keep track of whether the given parent path is a remote directory.
        #
        function PSGetRemotePathInfo
        {{
            param (
                [string] $remotePath
            )

            try
            {{

                try
                {{
                    $parentPath = Microsoft.PowerShell.Management\Split-Path $remotePath
                }}
                # catch everything and ignore the error.
                catch {{}}

                $result = @{{
                    IsFileInfo = (Microsoft.PowerShell.Management\Test-Path $remotePath -PathType Leaf)
                    IsDirectoryInfo = (Microsoft.PowerShell.Management\Test-Path $remotePath -PathType Container)
                }}

                if ($parentPath)
                {{
                    $result['ParentIsDirectoryInfo'] = (Microsoft.PowerShell.Management\Test-Path $parentPath -PathType Container)
                }}

            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}

            return $result
        }}

        # Returns a hashtable with the following information:
        #  - IsFileInfotrue bool to keep track if the given destination is a FileInfo type.
        function PSRemoteDestinationPathIsFile
        {{
            param (
                [string] $isFilePath
            )

            $op = @{{
                IsFileInfo = $null
            }}

            try
            {{
                $op['IsFileInfo'] = (Microsoft.PowerShell.Management\Test-Path $isFilePath -PathType Leaf)
            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}

            return $op
        }}

        # Return a hash table in the following format:
        #      DirectoryPath is the directory to be created.
        #      PathExists is a bool to keep track of whether the directory already exist.
        #
        # 1) If DirectoryPath already exists:
        #     a) If -Force is specified, force create the directory. Set DirectoryPath to the created directory path.
        #     b) If not -Force is specified, then set PathExists to $true.
        # 2) If DirectoryPath does not exist, create it. Set DirectoryPath to the created directory path.
        function PSCreateDirectoryOnRemoteSession
        {{
            param (
                [string] $createDirectoryPath,
                [switch] $force = $false
            )

            $op = @{{
                DirectoryPath = $null
                PathExists = $false
            }}

            try
            {{
                if (Microsoft.PowerShell.Management\Test-Path $createDirectoryPath)
                {{
                    # -Force is specified, then force create the directory.
                    if ($force)
                    {{
                        Microsoft.PowerShell.Management\New-Item $createDirectoryPath -ItemType Directory -Force | Out-Null
                        $op['DirectoryPath'] = $createDirectoryPath
                    }}
                    else
                    {{
                        $op['PathExists'] = $true
                    }}
                }}
                else
                {{
                    Microsoft.PowerShell.Management\New-Item $createDirectoryPath -ItemType Directory | Out-Null
                    $op['DirectoryPath'] = $createDirectoryPath
                }}
            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}

            return $op
        }}

        #
        # Call helper function based on bound parameter set
        #
        $params = $PSCmdlet.MyInvocation.BoundParameters
        switch ($PSCmdlet.ParameterSetName)
        {{
            ""PSCopyFileToRemoteSession""
            {{
                return PSCopyFileToRemoteSession @params
            }}

            ""PSCopyAlternateStreamToRemoteSession""
            {{
                return PSCopyFileAlternateStreamToRemoteSession @params
            }}

            ""PSTargetSupportsAlternateStreams""
            {{
                return PSTargetSupportsAlternateStreams @params
            }}

            ""PSSetFileMetadata""
            {{
                return PSSetFileMetadata @params
            }}

            ""PSRemoteDestinationPathIsFile""
            {{
                return PSRemoteDestinationPathIsFile @params
            }}

            ""PSGetRemotePathInfo""
            {{
                return PSGetRemotePathInfo @params
            }}

            ""PSCreateDirectoryOnRemoteSession""
            {{
                return PSCreateDirectoryOnRemoteSession @params
            }}
        }}
        ";

        private static readonly string s_PSCopyToSessionHelper = functionToken + PSCopyToSessionHelperName + @"
        {
        " + s_PSCopyToSessionHelperDefinition + @"
        }
        ";

        private static readonly Hashtable s_PSCopyToSessionHelperFunction = new Hashtable() {
            {nameToken, PSCopyToSessionHelperName},
            {definitionToken, s_PSCopyToSessionHelperDefinitionRestricted}
        };

        #endregion

        #region PSCopyFromSessionHelper

        internal const string PSCopyFromSessionHelperName = @"PSCopyFromSessionHelper";

        private static readonly string s_PSCopyFromSessionHelperDefinition = StringUtil.Format(PSCopyFromSessionHelperDefinitionFormat, @"[ValidateNotNullOrEmpty()]");
        private static readonly string s_PSCopyFromSessionHelperDefinitionRestricted = StringUtil.Format(PSCopyFromSessionHelperDefinitionFormat, @"[ValidateUserDrive()]");

        private const string PSCopyFromSessionHelperDefinitionFormat = @"
        param (
            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"", Mandatory=$true)]
            {0}

            [string] $copyFromFilePath,

            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"", Mandatory=$true)]
            [ValidateRange(0, [long]::MaxValue)]
            [long] $copyFromStart,

            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"", Mandatory=$true)]
            [ValidateRange(0, [long]::MaxValue)]
            [long] $copyFromNumBytes,

            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"")]
            [switch] $force,

            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"")]
            [switch] $isAlternateStream,

            [Parameter(ParameterSetName=""PSCopyFileFromRemoteSession"")]
            [ValidateNotNullOrEmpty()]
            [string] $streamName,

            [Parameter(ParameterSetName=""PSSourceSupportsAlternateStreams"", Mandatory=$true)]
            {0}

            [string] $supportAltStreamPath,

            [Parameter(ParameterSetName=""PSGetFileMetadata"", Mandatory=$true)]
            {0}

            [string] $getMetaFilePath,

            [Parameter(ParameterSetName=""PSGetPathItems"", Mandatory=$true)]
            {0}

            [string] $getPathItems,

            [Parameter(ParameterSetName=""PSGetPathDirAndFiles"", Mandatory=$true)]
            {0}

            [string] $getPathDir
        )

        # A hash table with the following members is returned:
        #   - moreAvailable bool to keep track of whether there is more data available
        #   - b64Fragment to track of the number of bytes.
        #   - ExceptionThrown bool to keep track if an exception was thrown
        function PSCopyFileFromRemoteSession
        {{
            param(
                [string] $copyFromFilePath,
                [long] $copyFromStart,
                [long] $copyFromNumbytes,
                [switch] $force = $false,
                [switch] $isAlternateStream = $false,
                [string] $streamName
            )

            $finalResult = @{{
                b64Fragment = $null
                moreAvailable = $null
                ExceptionThrown = $false
            }}

            function PerformCopyFileFromRemoteSession
            {{
                param(
                    [string] $filePath,
                    [long] $start,
                    [long] $numBytes,
                    [switch] $isAlternateStream,
                    [string] $streamName
                )

                $op = @{{
                    b64Fragment = $null
                    moreAvailable = $false
                }}

                # Ensure bytes read is less than Max allowed
                $maxBytes = 10 * 1024 * 1024
                $numBytes = [Math]::Min($numBytes, $maxBytes)

                $rstream = $null
                try
                {{
                    if ($isAlternateStream)
                    {{
                        $content = Microsoft.PowerShell.Management\Get-Content $filePath -stream $streamName -Encoding Byte -Raw
                        $rstream = [System.IO.MemoryStream]::new($content)
                    }}
                    else
                    {{
                        $rstream = [System.IO.File]::OpenRead($filePath)
                    }}

                    # Create a new array to hold the file content
                    if ($start -lt $rstream.Length)
                    {{
                        $o = $rstream.Seek($start, 0)
                        $toRead = [Math]::Min($numBytes, $rstream.Length - $start)
                        $fragment = Microsoft.PowerShell.Utility\New-Object byte[] $toRead
                        $readsoFar = 0
                        while ($readsoFar -lt $toRead)
                        {{
                            $read = $rstream.Read($fragment, $readSoFar, $toRead - $readsoFar)
                            $readsoFar += $read
                        }}

                        $op['b64Fragment'] = [System.Convert]::ToBase64String($fragment)
                        if (($start + $readsoFar) -lt $rstream.Length)
                        {{
                            $op['moreAvailable'] = $true
                        }}
                    }}

                    $op
                }}
                finally
                {{
                    if ($null -ne $rstream)
                    {{
                        $rstream.Dispose()
                    }}
                }}
            }}

            function WriteException
            {{
                param ($ex)

                if ($ex.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $ex.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $ex.Exception
                }}

                $finalResult.ExceptionThrown = $true
            }}

            # Resolve path in case it is a PSDrive
            $resolvedFilePath = (Microsoft.PowerShell.Management\Resolve-Path -literal $copyFromFilePath).ProviderPath

            $unAuthorizedAccessException = $null
            $result = $null

            $isReadOnly = $false
            $isHidden = $false
            try
            {{
                $result = PerformCopyFileFromRemoteSession -filePath $resolvedFilePath -start $copyFromStart -numBytes $copyFromNumBytes -isAlternateStream:$isAlternateStream -streamName $streamName
                $finalResult.b64Fragment =  $result.b64Fragment
                $finalResult.moreAvailable =  $result.moreAvailable
            }}
            catch [System.UnauthorizedAccessException]
            {{
                $unAuthorizedAccessException = $_
                if ($force)
                {{
                    $exception = $null
                    try
                    {{
                        # Disable the readonly and hidden attributes and try again
                        $item = Microsoft.PowerShell.Management\Get-Item $resolvedFilePath

                        if ($item.Attributes.HasFlag([System.IO.FileAttributes]::Hidden))
                        {{
                            $isHidden = $true
                            $item.Attributes = $item.Attributes -band (-bnot ([System.IO.FileAttributes]::Hidden))
                        }}

                        if ($item.Attributes.HasFlag([System.IO.FileAttributes]::ReadOnly))
                        {{
                            $isReadOnly = $true
                            $item.Attributes = $item.Attributes -band (-bnot ([System.IO.FileAttributes]::ReadOnly))
                        }}

                        $result = PerformCopyFileFromRemoteSession -filePath $resolvedFilePath -start $copyFromStart -numBytes $copyFromNumBytes -isAlternateStream:$isAlternateStream
                        $finalResult.b64Fragment =  $result.b64Fragment
                        $finalResult.moreAvailable =  $result.moreAvailable
                    }}
                    catch
                    {{
                        $e = $_
                        if (($e.Exception.InnerException -is [System.IO.FileNotFoundException]) -or
                            ($e.Exception.InnerException -is [System.IO.DirectoryNotFoundException]) -or
                            ($e.Exception.InnerException -is [System.Security.SecurityException] ) -or
                            ($e.Exception.InnerException -is [System.ArgumentException]) -or
                            ($e.Exception.InnerException -is [System.IO.IOException]))
                        {{
                            # Write out the original error since we failed to force the copy
                            WriteException $unAuthorizedAccessException
                        }}
                        else
                        {{
                            WriteException $e
                        }}

                        $finalResult.ExceptionThrown = $true
                    }}
                }}
                else
                {{
                    $finalResult.ExceptionThrown = $true
                    WriteException $unAuthorizedAccessException
                }}
            }}
            catch
            {{
                WriteException $_
            }}
            finally
            {{
                if ($isReadOnly)
                {{
                    $item.Attributes = $item.Attributes -bor [System.IO.FileAttributes]::ReadOnly
                }}

                if ($isHidden)
                {{
                    $item.Attributes = $item.Attributes -bor [System.IO.FileAttributes]::Hidden
                }}
            }}

            return $finalResult
        }}

        # Returns a hashtable with the following members:
        #    SourceSupportsAlternateStreams - boolean to keep track of whether the source supports Alternate data streams.
        #    Streams - the list of alternate streams
        #
        function PSSourceSupportsAlternateStreams
        {{
            param ([string]$supportAltStreamPath)

            $result = @{{
                SourceSupportsAlternateStreams = $false
                Streams = @()
            }}

            # Check if the source supports 'Get-Content -Stream'. This functionality was introduced in version 3.0.
            $getContentCmdlet = Microsoft.PowerShell.Core\Get-Command Microsoft.PowerShell.Management\Get-Content -ErrorAction SilentlyContinue
            if ($getContentCmdlet.Parameters.Keys -notcontains 'Stream')
            {{
                return $result
            }}

            $result['SourceSupportsAlternateStreams'] = $true

            # Check if the file has any alternate data streams.
            $item = Microsoft.PowerShell.Management\Get-Item -Path $supportAltStreamPath -Stream * -ea SilentlyContinue
            if (-not $item)
            {{
                return $result
            }}

            foreach ($streamName in $item.Stream)
            {{
                if ($streamName -ne ':$DATA')
                {{
                    $result['Streams'] += $streamName
                }}
            }}

            return $result
        }}

        # Returns a hash table with metadata info about the file for the given path.
        #
        function PSGetFileMetadata
        {{
            param ($getMetaFilePath)

            if (-not (Microsoft.PowerShell.Management\Test-Path $getMetaFilePath))
            {{
                return
            }}

            $item = Microsoft.PowerShell.Management\Get-Item $getMetaFilePath -Force -ea SilentlyContinue
            if ($item)
            {{
                $metadata = @{{}}

                # Attributes
                $attributes = @($item.Attributes.ToString().Split(',').Trim())
                if ($attributes.Count -gt 0)
                {{
                    $metadata.Add('Attributes', $attributes)
                }}

                # LastWriteTime
                $metadata.Add('LastWriteTime', $item.LastWriteTime)
                $metadata.Add('LastWriteTimeUtc', $item.LastWriteTimeUtc)

                return $metadata
            }}
        }}

        # Converts file system path to PSDrive path
        #    Returns converted path or original path if not conversion is needed.
        function ConvertToPSDrivePath
        {{
            param (
                [System.Management.Automation.PSDriveInfo] $driveInfo,
                [string] $pathToConvert
            )

            if (!($driveInfo) -or !($driveInfo.Name) -or !($driveInfo.Root))
            {{
                return $pathToConvert
            }}

            if (! ($driveInfo.Root.StartsWith($driveInfo.Name)))
            {{
                return $pathToConvert.ToUpper().Replace($driveInfo.Root.ToUpper(), (($driveInfo.Name) + "":""))
            }}

            return $pathToConvert
        }}

        ## A hashtable is returned in the following format:
        ##  Exists - Boolean to keep track if the given path exists.
        ##  Items  - The items that Get-Item -Path $path resolves to.
        function PSGetPathItems
        {{
            param (
                [string] $getPathItems
            )

            $op = @{{
                Exists = $null
                Items = $null
            }}

            try
            {{
                if (-not (Microsoft.PowerShell.Management\Test-Path $getPathItems))
                {{
                    $op['Exists'] = $false
                    return $op
                }}

                $items = @(Microsoft.PowerShell.Management\Get-Item -Path $getPathItems | Microsoft.PowerShell.Core\ForEach-Object {{
                    @{{
                        FullName = ConvertToPSDrivePath $_.PSDrive $_.FullName;
                        Name = $_.Name;
                        FileSize = $_.Length; IsDirectory = $_ -is [System.IO.DirectoryInfo]
                     }}
                }})
                $op['Exists'] = $true
                $op['Items'] = $items

                return $op
            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}

            return $op
        }}

        # Return a hashtable with the following members:
        # Files - Array with file fullnames, and their sizes
        # Directories - Array of child directory fullnames
        function PSGetPathDirAndFiles
        {{
            param (
                [string] $getPathDir
            )

            $result = @()

            $op = @{{
                Files = $null
                Directories = $null
            }}

            try
            {{
                $item = Microsoft.PowerShell.Management\Get-Item $getPathDir

                if ($item -isnot [System.IO.DirectoryInfo])
                {{
                    return $op
                }}

                $files = @(Microsoft.PowerShell.Management\Get-ChildItem -Path $getPathDir -File | Microsoft.PowerShell.Core\ForEach-Object {{
                    @{{ FileName = $_.Name;
                        FilePath = (ConvertToPSDrivePath $_.PSDrive $_.FullName);
                        FileSize = $_.Length
                     }}
                }})

                $directories = @(Microsoft.PowerShell.Management\Get-ChildItem -Path $getPathDir -Directory | Microsoft.PowerShell.Core\ForEach-Object {{
                    @{{ Name = $_.Name;
                        FullName = (ConvertToPSDrivePath $_.PSDrive $_.FullName)
                     }}
                }})

                if ($files.count -gt 0)
                {{
                    $op['Files'] = $files
                }}

                if ($directories.count -gt 0)
                {{
                    $op['Directories'] = $directories
                }}
            }}
            catch
            {{
                if ($_.Exception.InnerException)
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception.InnerException
                }}
                else
                {{
                    Microsoft.PowerShell.Utility\Write-Error -Exception $_.Exception
                }}
            }}

            return $op
        }}

        #
        # Call helper function based on bound parameter set
        #
        $params = $PSCmdlet.MyInvocation.BoundParameters
        switch ($PSCmdlet.ParameterSetName)
        {{
            ""PSCopyFileFromRemoteSession""
            {{
                return PSCopyFileFromRemoteSession @params
            }}

            ""PSSourceSupportsAlternateStreams""
            {{
                PSSourceSupportsAlternateStreams @params
            }}

            ""PSGetFileMetadata""
            {{
                PSGetFileMetadata @params
            }}

            ""PSGetPathItems""
            {{
                PSGetPathItems @params
            }}

            ""PSGetPathDirAndFiles""
            {{
                PSGetPathDirAndFiles @params
            }}
        }}
        ";

        internal static readonly string PSCopyFromSessionHelper = functionToken + PSCopyFromSessionHelperName + @"
        {
        " + s_PSCopyFromSessionHelperDefinition + @"
        }
        ";

        private static readonly Hashtable s_PSCopyFromSessionHelperFunction = new Hashtable() {
            {nameToken, PSCopyFromSessionHelperName},
            {definitionToken, s_PSCopyFromSessionHelperDefinitionRestricted}
        };

        #endregion

        #region PSCopyRemoteUtils

        internal const string PSCopyRemoteUtilsName = @"PSCopyRemoteUtils";

        internal static readonly string PSCopyRemoteUtilsDefinition = StringUtil.Format(PSCopyRemoteUtilsDefinitionFormat, @"[ValidateNotNullOrEmpty()]", PSValidatePathFunction);
        private static readonly string s_PSCopyRemoteUtilsDefinitionRestricted = StringUtil.Format(PSCopyRemoteUtilsDefinitionFormat, @"[ValidateUserDrive()]", PSValidatePathFunction);

        private const string PSCopyRemoteUtilsDefinitionFormat = @"
        param (
            [Parameter(ParameterSetName=""PSRemoteDirectoryExist"", Mandatory=$true)]
            {0}

            [string] $dirPathExists,

            [Parameter(ParameterSetName=""PSValidatePath"", Mandatory=$true)]
            {0}

            [string] $pathToValidate,

            [Parameter(ParameterSetName=""PSValidatePath"")]
            [switch] $sourceIsRemote
        )

        # Returns a hashtable with the following member:
        #    Exists - boolean to keep track of whether the given path exists for a remote directory.
        #
        function PSRemoteDirectoryExist
        {{
            param (
                [string] $dirPathExists
            )

            $result = @{{ Exists = (Microsoft.PowerShell.Management\Test-Path $dirPathExists -PathType Container) }}

            return $result
        }}

        {1}

        #
        # Call helper function based on bound parameter set
        #
        $params = $PSCmdlet.MyInvocation.BoundParameters
        switch ($PSCmdlet.ParameterSetName)
        {{
            ""PSRemoteDirectoryExist""
            {{
                return PSRemoteDirectoryExist @params
            }}

            ""PSValidatePath""
            {{
                return PSValidatePath @params
            }}
        }}
        ";

        private const string PSValidatePathFunction = functionToken + "PSValidatePath" + @"
        {
        " + PSValidatePathDefinition + @"
        }
        ";

        internal const string PSValidatePathDefinition = @"
        # Return hashtable in the following format:
        #   Exists - boolean to keep track if the given path exists
        #   Root - the root for the given path. If wildcards are used, it returns the first drive root.
        #   IsAbsolute - boolean to keep track of whether the given path is absolute
        param (
            [string] $pathToValidate,
            [switch] $sourceIsRemote
        )

        function SafeGetDriveRoot
        {
            param (
                [System.Management.Automation.PSDriveInfo] $driveInfo
            )

            if (! ($driveInfo.Root.StartsWith($driveInfo.Name)))
            {
                return (($driveInfo.Name) + "":"")
            }
            else
            {
                $driveInfo.Root
            }
        }

        $result = @{
            Exists = $null
            Root = $null
            IsAbsolute = $null
        }

        # Validate if the path is absolute
        $result['IsAbsolute'] = (Microsoft.PowerShell.Management\Split-Path $pathToValidate -IsAbsolute)
        if (-not $result['IsAbsolute'])
        {
            return $result
        }

        # Check if the given path exists.
        $result['Exists'] = (Microsoft.PowerShell.Management\Test-Path $pathToValidate)

        # If $pathToValidate is a remote source, and it does not exist, return.
        if ($sourceIsRemote -and (-not $result['Exists']))
        {
            return $result
        }

        # If the path does not exist, check if we can find its root.
        if (-not (Microsoft.PowerShell.Management\Test-Path $pathToValidate))
        {
            $possibleRoot = $null

            try
            {
                $possibleRoot = [System.IO.Path]::GetPathRoot($pathToValidate)
            }
            # Catch everything and ignore the error.
            catch {}

            if (-not $possibleRoot)
            {
                return $result
            }

            # Now use this path to find its root.
            $pathToValidate = $possibleRoot
        }

        # Get the root path using Get-Item
        $item = Microsoft.PowerShell.Management\Get-Item $pathToValidate -ea SilentlyContinue
        if (($null -ne $item) -and ($item[0].PSProvider.Name -eq 'FileSystem'))
        {
            $result['Root'] = SafeGetDriveRoot $item[0].PSDrive
            return $result
        }

        # If this fails, try to get them via Get-PSDrive
        $fileSystemDrives = @(Microsoft.PowerShell.Management\Get-PSDrive -PSProvider FileSystem -ea SilentlyContinue)

        # If this fails, try to get them via Get-PSProvider
        if ($fileSystemDrives.Count -eq 0)
        {
            $fileSystemDrives = @((Microsoft.PowerShell.Management\Get-PSProvider -PSProvider FileSystem -ea SilentlyContinue).Drives)
        }

        foreach ($drive in  $fileSystemDrives)
        {
            if ($pathToValidate.StartsWith($drive.Root))
            {
                $result['Root'] = SafeGetDriveRoot $drive
                break
            }
        }

        return $result
        ";

        internal static readonly string PSCopyRemoteUtils = functionToken + PSCopyRemoteUtilsName + @"
        {
        " + PSCopyRemoteUtilsDefinition + @"
        }
        ";

        internal static readonly Hashtable PSCopyRemoteUtilsFunction = new Hashtable() {
            {nameToken, PSCopyRemoteUtilsName},
            {definitionToken, s_PSCopyRemoteUtilsDefinitionRestricted}
        };

        #endregion

        internal static readonly string AllCopyToRemoteScripts = s_PSCopyToSessionHelper + PSCopyRemoteUtils;

        internal static IEnumerable<Hashtable> GetAllCopyToRemoteScriptFunctions()
        {
            yield return s_PSCopyToSessionHelperFunction;
            yield return PSCopyRemoteUtilsFunction;
        }

        internal static readonly string AllCopyFromRemoteScripts = PSCopyFromSessionHelper + PSCopyRemoteUtils;

        internal static IEnumerable<Hashtable> GetAllCopyFromRemoteScriptFunctions()
        {
            yield return s_PSCopyFromSessionHelperFunction;
            yield return PSCopyRemoteUtilsFunction;
        }
    }

    #endregion
}
