#!/bin/sh
# gen-release-tarballs.sh  -  Generates release tarballs with signatures
#
# Copyright (C) 2017-2018 - David Sommerseth <davids@openvpn.net>
#
# 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.
#
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
set -u

if [ $# -ne 4 ]; then
    echo "Usage: $0 <remote-name> <tag-name> <sign-key> <dest-dir>"
    echo ""
    echo "   remote-name  -- valid remotes: `git remote | tr \\\n ' '`"
    echo "   tag-name     -- An existing release tag"
    echo "   sign-key     -- PGP key used to sign all files"
    echo "   dest-dir     -- Where to put the complete set of release tarballs"
    echo ""
    echo "   Example: $0 origin v2.4.2 /tmp/openvpn-release"
    echo
    exit 1
fi

arg_remote_name="$1"
arg_tag_name="$2"
arg_sign_key="$3"
arg_dest_dir="$4"

#
# Sanity checks
#

# Check that the tag exists
git tag | grep "$arg_tag_name" 1>/dev/null
if [ $? -ne 0 ]; then
    echo "** ERROR **  The tag '$arg_tag_name' does not exist"
    exit 2
fi

# Extract the git URL
giturl="`git remote get-url $arg_remote_name 2>/dev/null`"
if [ $? -ne 0 ]; then
    echo "** ERROR ** Invalid git remote name: $arg_remote_name"
    exit 2
fi

# Check we have the needed signing key
echo "test" | gpg -a --clearsign -u "$arg_sign_key" 2>/dev/null 1>/dev/null
if [ $? -ne 0 ]; then
    echo "** ERROR ** Failed when testing the PGP signing.  Wrong signing key?"
    exit 2;
fi


#
# Helper functions
#

get_filename()
{
    local wildcard="$1"

    res="`find . -maxdepth 1 -type f -name \"$wildcard\" | head -n1 | cut -d/ -f2-`"
    if [ $? -ne 0 ]; then
        echo "-- 'find' failed."
        exit 5
    fi
    if [ -z "$res" ]; then
        echo "-- Could not find a file with the wildcard: $wildcard"
        exit 4
    fi
    echo "$res"
}

copy_files()
{
    local fileext="$1"
    local dest="$2"

    file="`get_filename openvpn-*.*.*.$fileext`"
    if [ -z "$file" ]; then
        echo "** ERROR Failed to find source file"
        exit 5
    fi
    echo "-- Copying $file"
    cp "$file" "$dest"
    if [ $? -ne 0 ]; then
        echo "** ERROR ** Failed to copy $file to $destdir"
        exit 3;
    fi
}

sign_file()
{
    local signkey="$1"
    local srchfile="$2"
    local signtype="$3"
    local file="`get_filename $srchfile`"

    echo "-- Signing $file ..."
    case "$signtype" in
        inline)
            # Have the signature in the same file as the data
            gpg -a --clearsign -u "$signkey" "$file" 2>/dev/null
            res=$?
            if [ $res -eq 0 ]; then
                rm -f "$file"
            fi
            ;;

        detached)
            # Have the signature in a separate file
            gpg -a --detach-sign -u "$signkey" "$file" 2>/dev/null
            res=$?
            ;;

        *)
            echo "** ERROR **  Unknown signing type \"$signtype\"."
            exit 4;
    esac

    if [ $res -ne 0 ]; then
        echo "** ERROR **  Failed to sign the file $PWD/$file"
        exit 4;
    fi
}


#
# Preparations
#

# Create the destination directory, using a sub-dir with the tag-name
destdir=""
case "$arg_dest_dir" in
    /*) # Absolute path
        destdir="$arg_dest_dir/$arg_tag_name"
        ;;
    *)  # Make absolute path from relative path
        destdir="$PWD/$arg_dest_dir/$arg_tag_name"
        ;;
esac
echo "-- Destination directory: $destdir"
if [ -e "$destdir" ]; then
    echo "** ERROR ** Destination directory already exists.  "
    echo "            Please check your command line carefully."
    exit 2
fi

mkdir -p "$destdir"
if [ $? -ne 0 ]; then
    echo "** ERROR ** Failed to create destination directory"
    exit 2
fi

#
# Start the release process
#

# Clone the remote repository
workdir="`mktemp -d -p /var/tmp openvpn-build-release-XXXXXX`"
cd $workdir
echo "-- Working directory: $workdir"
echo "-- git clone $giturl"
git clone $giturl openvpn-gen-tarball 2> "$workdir/git-clone.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  git clone failed.  See $workdir/git-clone.log for details"
    exit 3;
fi
cd openvpn-gen-tarball

# Check out the proper release tag
echo "-- Checking out tag $arg_tag_name ... "
git checkout -b mkrelease "$arg_tag_name" 2> "$workdir/git-checkout-tag.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  git checkout failed.  See $workdir/git-checkout-tag.log for details"
    exit 3;
fi

# Prepare the source tree
echo "-- Running autoreconf + a simple configure ... "
(autoreconf -vi && ./configure) 2> "$workdir/autotools-prep.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  Failed running autotools.  See $workdir/autotools-prep.log for details"
    exit 3;
fi

# Generate the tar/zip files
echo "-- Running make distcheck (generates .tar.gz) ... "
(make distcheck) 2> "$workdir/make-distcheck.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  make distcheck failed.  See $workdir/make-distcheck.log for details"
    exit 3;
fi
copy_files tar.gz "$destdir"

echo "-- Running make dist-xz (generates .tar.xz) ... "
(make dist-xz) 2> "$workdir/make-dist-xz.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  make dist-xz failed.  See $workdir/make-dist-xz.log for details"
    exit 3;
fi
copy_files tar.xz "$destdir"

echo "-- Running make dist-zip (generates .zip) ... "
(make dist-zip) 2> "$workdir/make-dist-zip.log" 1>&2
if [ $? -ne 0 ]; then
    echo "** ERROR **  make dist-zip failed.  See $workdir/make-dist-zip.log for details"
    exit 3;
fi
copy_files zip "$destdir"

# Generate SHA256 checksums
cd "$destdir"
sha256sum openvpn-*.tar.{gz,xz} openvpn-*.zip > "openvpn-$arg_tag_name.sha256sum"

# Sign all the files
echo "-- Signing files ... "
sign_file "$arg_sign_key" "openvpn-$arg_tag_name.sha256sum" inline
sign_file "$arg_sign_key" "openvpn-*.tar.gz" detached
sign_file "$arg_sign_key" "openvpn-*.tar.xz" detached
sign_file "$arg_sign_key" "openvpn-*.zip" detached

# Create a tar-bundle with everything
echo "-- Creating final tarbundle with everything ..."
tar cf "openvpn-$arg_tag_name.tar" openvpn-*.{tar.gz,tar.xz,zip}{,.asc} openvpn-*.sha256sum.asc

echo "-- Cleaning up ..."
# Save the log files
mkdir -p "$destdir/logs"
mv $workdir/*.log "$destdir/logs"

# Finally, done!
rm -rf "$workdir"
echo "-- Done"
exit 0