/**
 * Copyright (C) 2001-2015 Klaralvdalens Datakonsult AB.  All rights reserved.
 *
 * This file is part of the KGantt library.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "kganttconstraint.h"
#include "kganttconstraint_p.h"

#include <QDateTime>

using namespace KGantt;

/*!\class KGantt::Constraint
 *\ingroup KGantt
 * \brief A class used to represent a dependency.
 *
 * Instances of this class represent a dependency between the
 * data items pointed to by a start-QModelIndex and an
 * end-QModelIndex.
 */

/*!\enum KGantt::Constraint::Type
 * This enum is unused for now.
 */

/*!\enum KGantt::Constraint::ConstraintDataRole
 * Data roles used when specifying the pen to draw constraints with.
 * \sa setData
 */

Constraint::Private::Private()
    : type( TypeSoft ),
      relationType( FinishStart )
{
}

Constraint::Private::Private( const Private& other )
    : QSharedData( other ),
      start( other.start ),
      end( other.end ),
      type( other.type ),
      relationType( other.relationType ),
      data( other.data )
{
}

/*! Constructor. Creates a dependency for \a idx2 on \a idx1.
 * \param type controls if the constraint is a soft one that
 * is allowed to be broken (ie, go backwards in time) or a hard
 * constraint that will not allow the user to move an item so
 * that the constraint would have to go backwards. The default is
 * TypeSoft.
 *
 * Actually enforcing hard constraints is the responsibility of
 * the AbstractGrid subclass used in the view.
 *
 * \param relationType defines how the tasks depends on each other.
 * relationType can be FinishStart (default), FinishFinish, StartStart or StartFinish.
 */
Constraint::Constraint( const QModelIndex& idx1,
                        const QModelIndex& idx2,
                        Constraint::Type type,
                        Constraint::RelationType relationType,
                        const Constraint::DataMap& datamap )
    : d( new Private )
{
    d->start=idx1;
    d->end=idx2;
    d->type=type;
    d->relationType=relationType;
    d->data=datamap;
    Q_ASSERT_X( idx1 != idx2 || !idx1.isValid(), "Constraint::Constraint", "cannot create a constraint with idx1 == idx2" );
}

/*! Default constructor, created an invalid constraint. */
Constraint::Constraint()
    : d( new Private )
{
}

/*! Copy-Constructor. */
Constraint::Constraint( const Constraint& other )
    : d( other.d )
{
}

/*! Destructor */
Constraint::~Constraint()
{
}

/*! Assignment operator. */
Constraint& Constraint::operator=( const Constraint& other )
{
    d = other.d;
    return *this;
}

/*! This is unused for now. */
Constraint::Type Constraint::type() const
{
    return d->type;
}

/*! This is unused for now. */
Constraint::RelationType Constraint::relationType() const
{
    return d->relationType;
}

/*! \returns The dependency index */
QModelIndex Constraint::startIndex() const
{
    return d->start;
}

/*! \returns The constrained index */
QModelIndex Constraint::endIndex() const
{
    return d->end;
}

/*! \returns The data associated with this index for the specified role.
 * \param role The role to fetch the data for.
 * \sa ConstraintDataRole
 */
QVariant Constraint::data( int role ) const
{
    return d->data.value( role );
}

/*! Set data on this index for the specified role.
 * \param role The role to set the data for.
 * \param value The data to set on the index.
 * \sa ConstraintDataRole
 */
void Constraint::setData( int role, const QVariant& value )
{
    d->data.insert( role, value );
}

/*! Set data on this constraint to the keys/values in \a datamap.
 * Clears any existing data from the constraint.
 */
void Constraint::setDataMap( const QMap< int, QVariant >& datamap )
{
    d->data = datamap;
}

/*! \returns all the data set on this constraint. \see setDataMap
 */
QMap< int, QVariant > Constraint::dataMap() const
{
    return d->data;
}


bool Constraint::compareIndexes(const Constraint& other) const
{
    return (d->start==other.startIndex() || (!d->start.isValid() && !other.startIndex().isValid()))
        && (d->end==other.endIndex() || (!d->end.isValid() && !other.endIndex().isValid()));
}

/*! Compare two Constraint objects. Two Constraints are equal
 * if the have the same start and end indexes
 */
bool Constraint::operator==( const Constraint& other ) const
{
    if ( d == other.d ) return true;
    return ( *d ).equals( *( other.d ) );
}

/*!\internal*/
uint Constraint::hash() const
{
    return ::qHash( d->start ) ^ ::qHash( d->end ) ^ ::qHash( static_cast<uint>( d->type ) );
}

#ifndef QT_NO_DEBUG_STREAM

QDebug operator<<( QDebug dbg, const Constraint& c )
{
    return c.debug( dbg );
}

QDebug Constraint::debug( QDebug dbg ) const
{
    dbg << "KGantt::Constraint[ start=" << d->start << "end=" << d->end << "relationType=" << d->relationType << "], data=" << d->data;
    return dbg;
}

#endif /* QT_NO_DEBUG_STREAM */

#ifndef KDAB_NO_UNIT_TESTS

#include <QStandardItemModel>

#include "unittest/test.h"

KDAB_SCOPED_UNITTEST_SIMPLE( KGantt, Constraint, "test" )
{
    QStandardItemModel dummyModel( 100, 100 );
    QModelIndex idx1 = dummyModel.index( 7, 17, QModelIndex() );
    QModelIndex idx2 = dummyModel.index( 42, 17, QModelIndex() );

    Constraint c1 = Constraint( QModelIndex(), QModelIndex(), Constraint::TypeSoft );
    Constraint c2 = Constraint( QModelIndex(), QModelIndex(), Constraint::TypeSoft );
    Constraint c3 = c2;
    Constraint c4( idx1, idx2 );
    Constraint c5( idx2, idx1 );

    assertTrue( c1==c2 );
    assertEqual( qHash( c1 ), qHash( c2 ) );
    assertTrue( c1==c3 );
    assertEqual( qHash( c1 ), qHash( c3 ) );
    assertTrue( c2==c3 );
    assertEqual( qHash( c2 ), qHash( c3 ) );

    assertFalse( c2==c4 );
    assertNotEqual( qHash( c2 ), qHash( c4 ) );

    assertFalse( c4==c5 );

    assertEqual( c3.type(), Constraint::TypeSoft );

    dummyModel.removeRow( 8 );
    assertFalse( c4==c5 );
}

#endif /* KDAB_NO_UNIT_TESTS */
