dad

#! /bin/dash

usage() {
    printf '%s [-h|-d DOWNLOAD_DIR] start|stop\n' "${0##*/}"
}

download_dir=${DIANA_DOWNLOAD_DIR:-${XDG_DOWNLOAD_DIR:-${HOME}}}

while getopts 'hd:' opt ; do
    case "$opt" in
        h)
            usage
            exit 0
            ;;
        d)
            download_dir=$OPTARG
            ;;
    esac
done

shift $((OPTIND - 1))

if [ $# -ne 1 ] ; then
    usage
    exit 1
fi

daemon_pid=/tmp/diana-daemon.pid

case "$1" in
    start)
        if [ -e "$daemon_pid" ] ; then
            printf '%s\n' 'The daemon is already running.' >&2
            exit 1
        fi

        XDG_DATA_HOME=${XDG_DATA_HOME:-${HOME}/.local/share}
        diana_session=${XDG_DATA_HOME}/diana.session

        [ ! -e "$diana_session" ] && touch "$diana_session"

        aria2c --daemon --enable-rpc --continue --dir "$download_dir" --input-file "$diana_session" --save-session "$diana_session"

        pgrep -nx aria2c > "$daemon_pid"

        if [ $? -ne 0 ] ; then
            printf '%s\n' 'The daemon failed to start.' >&2
            rm "$daemon_pid"
            exit 1
        fi
        ;;
    stop)
        if [ ! -e "$daemon_pid" ] ; then
            printf '%s\n' 'The daemon is not running.' >&2
            exit 1
        fi

        # kill $(cat "$daemon_pid") > /dev/null 2>&1
        pkill -g $(cat "$daemon_pid") > /dev/null 2>&1

        if [ $? -ne 0 ] ; then
            printf '%s\n' 'Could not stop the daemon.' >&2
            exit 1
        else
            rm "$daemon_pid"
        fi
        ;;
esac