#!/bin/sh
# 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; 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.

FORCE="n"
RUN=""
MAKEPKG_ARGS="-Ss"
WORKDIR=$PWD

chrootdir="$CHROOT_SHELL"

APPNAME=$(basename "${0}")

usage ()
{
    echo "usage ${APPNAME} [-h] [-c CHROOT_SHELL] [--] [makepkg args]"
    echo " Run this script in a PKGBUILD dir to build a package inside a"
    echo " clean chroot. All unrecognized arguments passed to this script"
    echo " will be passed to makepkg."
    echo ""
    echo "The \$CHROOT_SHELL environment variable is used to determine where"
    echo " your chroot shell is. The shell consists of the following"
    echo " directories: \$CHROOT_SHELL/{root, rw, union} but only 'root' is"
    echo " required by default. The rest will be created as needed"
    echo ""
    echo "The chroot shell 'root' directory must be created via the following"
    echo "command:"
    echo "    mkarchroot \$CHROOT_SHELL/root base base-devel sudo"
    echo ""
    echo "If you have problems passing params to makepkg or need to pass long"
    echo "options, put -- between the makechrootpkg args and the makepkg args"
    echo ""
    echo "Default makepkg args: $MAKEPKG_ARGS"
    exit 1
}

while getopts ':c:h' arg; do
    case "${arg}" in
        c) chrootdir="$OPTARG" ;;
        h|?) usage ;;
        *) MAKEPKG_ARGS="$MAKEPKG_ARGS -$arg $OPTARG" ;;
    esac
done

# Pass all arguments after -- right to makepkg
MAKEPKG_ARGS="$MAKEPKG_ARGS ${*:$OPTIND}"

if [ "$EUID" != "0" ]; then
    echo "This script must be run as root."
    exit 1
fi

if [ ! -f PKGBUILD ]; then
	echo "This must be run in a directory containing a PKGBUILD."
	exit 1
fi
source PKGBUILD

if [ ! -d "$chrootdir" ]; then
    echo "No \$CHROOT_SHELL defined, or invalid path"
    exit 1
fi

if [ ! -d "$chrootdir/root" ]; then
    echo "Missing \$CHROOT_SHELL root directory."
    echo "Try using: mkarchroot \$CHROOT_SHELL base base-devel sudo"
    usage
fi

[ -d "$chrootdir/rw" ] || mkdir "$chrootdir/rw"
[ -d "$chrootdir/union" ] || mkdir "$chrootdir/union"

function cleanup ()
{
    echo "cleaning up unioned mounts"
    umount "$chrootdir/union"
}

uniondir="$chrootdir/union"
echo "building union chroot"
modprobe -q unionfs
mount -t unionfs none -o "dirs=$chrootdir/rw=rw:$chrootdir/root=ro" "$uniondir"
trap 'cleanup' 0 1 2 15

echo "moving build files to chroot"
[ -d "$uniondir/build" ] || mkdir "$uniondir/build"
chown -R nobody "$uniondir/build"

source PKGBUILD
cp PKGBUILD "$uniondir/build/"
for f in ${source[@]}; do
    if [ -f "$f" ]; then
        cp "$f" "$uniondir/build/"
    fi
done
if [ "$install" != "" -a -f "$install" ]; then
    cp "$install" "$uniondir/build/"
fi

if ! grep "^nobody" "$uniondir/etc/sudoers" >/dev/null 2>&1; then
    echo "allowing 'nobody' sudo rights in the chroot"
    echo "nobody	ALL=(ALL) NOPASSWD: ALL" >> "$uniondir/etc/sudoers"
    chmod 440 "$uniondir/etc/sudoers"
fi

#This is a little gross, but this way the script is recreated every time in the
#rw portion of the union
(cat <<EOF
#!/bin/bash
export LANG=$LOCALE
cd /build
sudo -u nobody makepkg $MAKEPKG_ARGS || touch BUILD_FAILED
EOF
) > "$uniondir/chrootbuild"
chmod +x "$uniondir/chrootbuild"

mkarchroot -r "/chrootbuild" "$uniondir"

if [ -e ${chrootdir}/rw/build/BUILD_FAILED ]; then
	echo "Build failed, check \$CHROOT_DIR/rw/build"
	rm ${chrootdir}/rw/build/BUILD_FAILED
        exit 1
else	
	source ${WORKDIR}/PKGBUILD
	mv ${chrootdir}/rw/build/${pkgname}-${pkgver}-*.pkg.tar.gz ${WORKDIR}
	rm -rf ${chrootdir}/rw/build/* 
	echo "Build complete"
fi