#!/bin/bash
#------------------------------------------------------------------------------
# =========                 |
# \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
#  \\    /   O peration     |
#   \\  /    A nd           | www.openfoam.com
#    \\/     M anipulation  |
#------------------------------------------------------------------------------
#     Copyright (C) 2019 OpenCFD Ltd.
#------------------------------------------------------------------------------
# License
#     This file is part of OpenFOAM.
#
#     OpenFOAM 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 3 of the License, or
#     (at your option) any later version.
#
#     OpenFOAM 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 OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
#
# Script
#     foamPackRelease [OPTION]
#
# Description
#     Simple script generator for packing OpenFOAM sources and submodules
#
#       $ foamPackRelease -output=some/path origin/master > create-tar
#       $ bash ./create-tar
#
#     Or directly:
#
#       $ foamPackRelease -tgz origin/master | bash
#
#     Done as two-step process to allow further manual adjustments as required
#------------------------------------------------------------------------------
Script="${0##*/}"

usage() {
    exec 1>&2
    while [ "$#" -gt 0 ]; do echo "$1"; shift; done
cat <<USAGE

Usage: ${0##*/} [OPTION] commit-ish
options:
   -output=dir      Write to alternative output directory
   -no-modules      Exclude submodules
   -no-patch        Ignore _patch number for the output tar-file
   -compress=TYPE   Compress with specified type
   -sep=SEP         Change the patch, version separator from '_' to SEP
   -tgz             Alias for -compress=tgz
   -help            Print help

Simple script generator for packing OpenFOAM and submodules.
Eg,

    $Script -output some-directory origin/master > create-tar
    sh ./create-tar

    $Script -tgz origin/master | bash

USAGE
    exit 1
}

# Report error and exit
die()
{
    exec 1>&2
    echo
    echo "Error encountered:"
    while [ "$#" -ge 1 ]; do echo "    $1"; shift; done
    echo
    echo "See '${0##*/} -help' for usage"
    echo
    exit 1
}


#-------------------------------------------------------------------------------
outputDir="."
versionSeparator='_'
unset compress skipModules skipPatchNum

while [ "$#" -gt 0 ]
do
    case "$1" in
    -h | -help*)
        usage
        ;;
    -output)
        [ "$#" -ge 2 ] || usage "'$1' option requires an argument"
        outputDir="$2"
        shift
        ;;
    -output=*)
        outputDir="${1#*=}"
        ;;
    -no-modules)
        skipModules=true
        ;;
    -no-patch)
        skipPatchNum=true
        ;;
    -compress=*)
        compress="${1#*=}"
        ;;
    -sep=*)
        versionSeparator="${1#*=}"
        ;;
    -tgz)
        compress="${1#*-}"
        ;;
    -*)
        usage "unknown option: '$*'"
        ;;
    *)
        break
        ;;
    esac
    shift
done

commit="$1"
[ "$#" -eq 1 ] && [ -n "$commit" ] || usage "Requires one argument"

# Failsafe patch, version separator
: "${versionSeparator:=_}"

#-------------------------------------------------------------------------------
# Resolve the output directory
outputDir="$(cd "$outputDir" 2>/dev/null && pwd -L)" || \
    die "Cannot resolve output directory"

[ -w "$outputDir" ] || \
    die "Output directory non-writable: $outputDir"

echo "Using outputDir=$outputDir" 1>&2

#-------------------------------------------------------------------------------
# Locate the git repository

# Locate git-dir via rev-parse
findGitDir()
{
    (
        if cd "$1" 2>/dev/null && \
            git rev-parse --is-inside-work-tree > /dev/null 2>&1
        then
            git rev-parse --show-toplevel 2>/dev/null
        fi
    )
}

echo "Find git repository ... from script location" 1>&2
gitbase=$(findGitDir "${0%/*}")

##DEBUG unset gitbase
if [ -z "$gitbase" ]
then
    echo "Find git repository ... from current directory" 1>&2
    gitbase=$(findGitDir "$PWD")
fi

[ -d "$gitbase" ] || die "Could not locate a git directory"
echo "Detected git repository at $gitbase" 1>&2


# Resolve the given commit-ish to a real commit number.
# Eg, origin/master on input, SHA1 on output
head="$(git --git-dir="$gitbase/.git" rev-parse "$commit")"

[ -n "$head" ] || die "Could resolve requested start point $commit"
echo "Resolved $commit as $head" 1>&2

#-------------------------------------------------------------------------------
# Determine the API and PATCH numbers.
# Extract from META-INFO/api-info

unset api patch sha1

# Grab the sha1 for the file
sha1=$(git --git-dir="$gitbase/.git" ls-tree "$head" META-INFO/api-info | \
    awk '{ if ($2 == "blob") { print $3 }}')


[ -n "$sha1" ] || die "Could locate git content for META-INFO/api-info"

# The api and patch
api="$(git --git-dir="$gitbase/.git" show "$sha1" | sed -ne s/api=//p)"
patch="$(git --git-dir="$gitbase/.git" show "$sha1" | sed -ne s/patch=//p)"

[ -n "$api" ] || die "Could resolve api value"

# Determine the BUILD information from git, as per wmakeBuildInfo.
build="$(git --git-dir="$gitbase/.git" log -1 --date=short --format='%h=%ad' 2>/dev/null|sed 's/-//g;s/=/-/')"

echo "Detected api, patch, build as '$api', '$patch', '$build'" 1>&2

# Define the output names
dirPrefix="OpenFOAM-v${api}"
tarName="OpenFOAM-v${api}"

if [ "$skipPatchNum" = true ]
then
    echo "Ignoring patch number for output name" 1>&2
elif [ "${patch:-0}" -gt 0 ]
then
    tarName="${tarName}${versionSeparator}${patch}"
fi

echo 1>&2
echo "Tar-file name:   $tarName.tar" 1>&2
echo "Directory name:  $dirPrefix/" 1>&2
echo 1>&2

#-------------------------------------------------------------------------------

# Create main tar
echo '#!/bin/bash'
echo "cd '$gitbase/' || exit"
echo "api='$api'"
echo "patch='${patch:-0}'"
echo "build='$build'"
echo "head='$head'"
echo "outputDir='$outputDir'"
echo "dirPrefix='$dirPrefix'"
echo "tarName='$tarName'"
# Note - directory separator '/' encoded as '@' for manifest name
echo 'manifest="${dirPrefix}@META-INFO@manifest.txt"'
echo 'buildInfo="${dirPrefix}@META-INFO@build-info"'
echo '#--------'
echo 'set -x'
echo 'umask 0022'
echo 'git -c tar.umask=user archive --format=tar --prefix="$dirPrefix/" -o "$outputDir/$tarName.tar" "$head"'


# Tag build information with underscore to distinguish from "real" build
# information when git is available.
echo 'echo build="${build:+_}$build" > "$outputDir/$buildInfo"'

echo '{'
echo '  echo api="$api"'
echo '  echo patch="$patch"'
echo '  echo head="$head"'
echo '  echo'
echo '  git ls-tree -r "$head"'
echo '} > "$outputDir/$manifest"'


#------------------------------------------------------------------------------
# Add in mpdules
if [ "$skipModules" != true ]
then
    git --git-dir="$gitbase/.git" ls-tree "$head" modules/ | \
        while read mode gittype sha1 module
    do
        [ "$gittype" == commit ] || continue

        echo
        echo "module=\""$module"\""
        echo "commit=\""$sha1"\""
        echo "tarModule=\""$tarName-${module##*/}"\""
        echo
        echo 'if pushd "$module"; then'
        echo 'git -c tar.umask=user archive --format=tar --prefix="$dirPrefix/$module/" -o "$outputDir/$tarModule.tar" "$commit"'
        echo 'tar -Af "$outputDir/$tarName.tar" "$outputDir/$tarModule.tar"'
        echo 'rm -f "$outputDir/$tarModule.tar"'
        echo '{'
        echo '  echo'
        echo '  echo "$module"'
        echo '  echo commit="$commit"'
        echo '  echo'
        echo '  git ls-tree -r "$commit"'
        echo '} >> "$outputDir/$manifest"'
        echo 'popd; fi'
    done
fi

#------------------------------------------------------------------------------
# Add in build-info and manifest files
# Decode '@' in the names as '/' directory separator

echo
echo '{ echo; echo "# End"; } >> "$outputDir/$manifest"'

echo
echo "echo 'Adding build-info and manifest files'"
echo 'if pushd "$outputDir"; then'
echo "tar --owner=root --group=root --append --transform='s|@|/|g' -v -f \"\$tarName.tar\" \"\$buildInfo\" \"\$manifest\""
echo 'rm -f "$buildInfo" "$manifest"'
echo 'popd; fi'

echo
echo "# End of creating archive"
echo

#------------------------------------------------------------------------------
# Compression

case "$compress" in
    ('')
    echo "No compression requested" 1>&2
    ;;

    (gz | gzip)
    echo "Using gzip compression" 1>&2
    echo 'gzip -9 "$outputDir/$tarName.tar"'
    echo
    echo '# End of compression'
    ;;

    (tgz)
    echo "Using gzip compression with tgz ending" 1>&2
    echo 'gzip -c -9 "$outputDir/$tarName.tar" > "$outputDir/$tarName.tgz"'
    echo 'rm -f "$outputDir/$tarName.tar"'
    echo
    echo '# End of compression'
    ;;

    (bz | bzip | bzip2)
    echo "Using bzip2 compression" 1>&2
    echo 'bzip2 -9 "$outputDir/$tarName.tar"'
    echo
    echo '# End of compression'
    ;;

    (xz)
    echo "Using xz compression" 1>&2
    echo 'xz -9 "$outputDir/$tarName.tar"'
    echo
    echo '# End of compression'
    ;;

    (*)
    echo "Unknown compression scheme: $compress" 1>&2
    ;;
esac

#------------------------------------------------------------------------------