#!/bin/sh

FORCE="n"
RUN=""
MAKEPKG_ARGS="-Ss"

chrootdir="$CHROOT_SHELL"

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

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

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

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 base base-devel"
    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

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"
    exit 1
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' 1 2 15

echo "moving build files to chroot"
[ -d "$uniondir/build" ] || mkdir "$uniondir/build"

(
cat <<EOF
#!/bin/sh
su nobody
cd /build
makepkg $MAKEPKG_ARGS
EOF
) > "$uniondir/chrootbuild"
chmod +x "$uniondir/chrootbuild"

./mkarchroot -r "/chrootbuild" "$uniondir"

# TODO move relevant files here
echo "build complete... check \$CHROOT_SHELL/build for build results"