#!/bin/bash

# stop on any unhandled error
set -e

# @TODO: pipefail not in POSIX
set -o pipefail

# show commands (debug)
#set -x

# shellcheck source=src/container/output.inc.sh
source "/output.inc.sh"

# The .deb builders output all artifacts in the parent directory of the source
# directory, so ensure this scripts runs there
cd /tmp/build || (log_error "Unable to change directory to /tmp/build"; exit 1)

# Run Lintian, but don't exit on errors since 'unstable' and 'sid' releases
# will likely always emit errors if package complex enough
echo
log_info "Create lintian.log"
# Seems that --color=auto isn't enough inside a container, so use 'always'.
# Using --profle=debian is not needed as build container always matches target
# Debian/Ubuntu release and Lintian in them should automatically default to
# correct profile. Show info and overrides to be as verbose as possible.
lintian --verbose --info --color=always --display-level=">=pedantic" --display-experimental ./*.changes | tee -a "lintian.log" || true

# @TODO: Run Lintian in background (with & and later run 'wait') so that the
# filelist log can be created in parallel? Will it make overall progress faster?

# Run blhc, ignore errors caused by findings.
# Strip all ANSI terminal escape sequences, since otherwise blhc will not
# recognize the format. Sort file so comparing changes with diff is consistent
# and not polluted by parallel builds outputting build commands at random.
echo
log_info "Create blhc.log"
sed -E -e 's/\x1b\[[0-9;]+[mK]//g' "$BUILD_LOG" > /tmp/build_nocolor.log
blhc --all --color /tmp/build_nocolor.log | sort | tee -a "blhc.log" || true

# Symlink *.changes and *.buildinfo to an unversioned filename so that the diff
# steps that run later can compare them, and also meld can compare them
for x in *.buildinfo
do
  ln -sf "$x" buildinfo.log
done
for x in *.changes
do
  ln -sf "$x" changes.log
done

# Log package contents
echo
log_info "Create filelist.log"
for package in *.deb
do
  # Skip this if build was source-only and no *.deb files were found and
  # variable is just literal "*.deb"
  if [ "$package" == "*.deb" ]
  then
    break
  fi

  # shellcheck disable=SC2129
  echo "$package" | cut -d '_' -f 1 >> "filelist.log"
  dpkg-deb --contents "$package" | awk '{print $1 " " $2 " " $6 " " $7 " " $8}' | sort -k 3 >> "filelist.log"
  echo "------------------------------------------------" >> "filelist.log"
done

# @TODO: Both of these have the same output showing what files are new/changed
# and could be easily done, but offers no additional value:
#   debdiff --from previous/*.deb --to *.deb
#   debdiff previous/*.changes *.changes

# @TODO: Log output of `ldd -v` for each binary to track how dynamic dependencies change?

echo
log_info "Create control.log and maintainer-scripts.log"
for package in *.deb
do
  # Skip this if build was source-only and no *.deb files were found and
  # variable is just literal "*.deb"
  if [ "$package" == "*.deb" ]
  then
    break
  fi

  # shellcheck disable=SC2129
  PACKAGE_NAME="$(echo "$package" | cut -d '_' -f 1)"
  # Extract to directory with package name
  dpkg-deb --control "$package" "$PACKAGE_NAME"
  # Delete files not worth tracking
  (cd "$PACKAGE_NAME" && rm --force md5sums templates)

  # Copy 'control' contents into common file, but skip if directory has none
  if [ -n "$(ls --almost-all "$PACKAGE_NAME/control")" ]
  then
    # Use tail to list contents in one single file with headers between
    echo "==> $PACKAGE_NAME/control <==" >> control.log
    tail --lines=9999 "$PACKAGE_NAME"/control >> control.log
  fi

  # Clean up 'control' files, not needed in next step
  rm --recursive --force "$PACKAGE_NAME/control"

  # Copy 'pre/post/inst/rm' contents into common file, but skip if directory has none
  if [ -n "$(ls --almost-all "$PACKAGE_NAME/")" ]
  then
    # Use tail to list contents in one single file with headers between
    tail --lines=9999 "$PACKAGE_NAME"/* >> maintainer-scripts.log
  fi

  # Clean up temporary directory completely
  rm --recursive --force "$PACKAGE_NAME"
done

# Crude but fast and simple way to clean away ANSI color codes from logs
# @TODO: As 'less -K' and other tools support reading colored logs, we could
# consider keeping around colored logs in addition to plain logs for some files
sed -e 's/\x1b\[[0-9;]*[mK]//g' -i ./*.log

# Automatically do comparisons to previous build if exists
if [ -d "previous" ]
then
  for LOGFILE in *.log
  do
    # For each log, if a previous one with same name is found, create a diff
    # file but if there are no difference, remove the empty file
    if [ -f "previous/$LOGFILE" ]
    then
      ! diff -u "previous/$LOGFILE" "$LOGFILE" > "$LOGFILE.diff" || rm "$LOGFILE.diff" &
    fi
  done

  echo
  log_info "Create diffoscope report comparing to previous build"
  # Force diffoscope to terminate after 5 minutes. If diffoscope takes longer
  # than that, the output is probably massive and unreadable. Diffoscope is more
  # useful for hunting small changes which might be hard to find with other
  # tools.
  timeout --verbose --kill-after=8m 5m \
    diffoscope --html=diffoscope.html \
    --exclude='*.log' --exclude='*.diff' --exclude='*.build' --exclude='*.html' \
    --exclude=previous --exclude=last-tagged --exclude=source \
    previous/ . || true
    # Exit status is zero only if inputs are identical, so ignore exit code
fi

# @TODO: This is a duplicate of above as boilerplate before refactoring into
# functions
# Automatically do comparisons to previous build if exists
if [ -d "last-tagged" ]
then
  for LOGFILE in *.log
  do
    # For each log file can also be found from previous build, compare to
    # current using diff, but if there are no difference, remove the empty file
    if [ -f "last-tagged/$LOGFILE" ]
    then
      ! diff -u "last-tagged/$LOGFILE" "$LOGFILE" > "$LOGFILE.last-tagged.diff" || rm "$LOGFILE.last-tagged.diff" &
    fi
  done

  echo
  log_info "Create diffoscope report comparing to last tagged build"
  # Force diffoscope to terminate after 5 minutes. If diffoscope takes longer
  # than that, the output is probably massive and unreadable. Diffoscope is more
  # useful for hunting small changes which might be hard to find with other
  # tools.
  timeout --verbose --kill-after=8m 5m \
    diffoscope --html=diffoscope.last-tagged.html \
    --exclude='*.log' --exclude='*.diff' --exclude='*.build' --exclude='*.html' \
    --exclude=previous --exclude=last-tagged --exclude=source \
    last-tagged/ . || true
    # Exit status is zero only if inputs are identical, so ignore exit code
fi

# Note: Command `dpkg-deb --info filename.deb` just lists package size and
# debian/control snippet, not very useful for comparisons.
#
# Note: File list from commands `dpkg-deb --contents filename.deb` and `dpkg
# --contents filename.deb` is identical and contains fimestamps (of upstream
# release date?), so a diff would always show every single line as having
# changes and thus not suitable for comparisons.


# Wait to ensure all processes that were backgrounded earlier have completed too
wait

echo
log_info "Build completed in $((EPOCHSECONDS - BUILD_START_TIME)) seconds and created:"
# Don't show the mountpoint dir 'source'
ls --width=5 --size --human-readable --color=always --ignore={source,previous,last-tagged}
