#!/bin/sh

PATH=/sbin:/bin:/usr/sbin:/usr/bin

NAME=shepherd
DAEMON=/usr/bin/shepherd
PIDFILE=/run/shepherd.pid
CONFIG=/etc/shepherd.scm

case "$1" in
    start)
        echo "Starting Shepherd service manager..."

        if [ -f "$PIDFILE" ] &&
           kill -0 "$(cat "$PIDFILE")" 2>/dev/null
        then
            echo "Shepherd is already running."
            exit 0
        fi

        mkdir -p /run/shepherd
        chmod 755 /run/shepherd

        "$DAEMON" \
            --config="$CONFIG" \
            --pid="$PIDFILE"

        exit $?
        ;;

    stop)
        echo "Stopping Shepherd service manager..."

        if [ ! -f "$PIDFILE" ]; then
            echo "Shepherd is not running."
            exit 0
        fi

        PID="$(cat "$PIDFILE")"

        if kill -0 "$PID" 2>/dev/null; then
            kill -TERM "$PID"

            i=0
            while kill -0 "$PID" 2>/dev/null; do
                i=$((i + 1))

                if [ "$i" -ge 50 ]; then
                    kill -KILL "$PID" 2>/dev/null
                    break
                fi

                sleep 0.1
            done
        fi

        rm -f "$PIDFILE"

        exit 0
        ;;

    restart)
        "$0" stop
        "$0" start
        ;;

    status)
        if [ -f "$PIDFILE" ] &&
           kill -0 "$(cat "$PIDFILE")" 2>/dev/null
        then
            echo "Shepherd is running (PID $(cat "$PIDFILE"))."
            exit 0
        fi

        echo "Shepherd is not running."
        exit 3
        ;;

    *)
        echo "Usage: $0 {start|stop|restart|status}"
        exit 1
        ;;
esac