#!/system/bin/sh
# Foreground wrapper that daemonizes ddns-report.sh.
#
# Usage:
#   /data/local/tmp/ddns-runner.sh start   # start in background (nohup)
#   /data/local/tmp/ddns-runner.sh stop    # stop the running instance
#   /data/local/tmp/ddns-runner.sh status  # print pid + last log lines
#   /data/local/tmp/ddns-runner.sh restart
#
# The main script path and pid file can be overridden via env vars.

SCRIPT="${DDNS_SCRIPT:-/data/local/tmp/ddns-report.sh}"
PIDFILE="${DDNS_PIDFILE:-/data/local/tmp/ddns.pid}"
LOG_FILE="${DDNS_LOG_FILE:-/data/local/tmp/ddns.log}"

is_running() {
    [ -f "$PIDFILE" ] || return 1
    pid=$(cat "$PIDFILE" 2>/dev/null)
    [ -n "$pid" ] || return 1
    # kill -0 tests existence without signaling.
    kill -0 "$pid" 2>/dev/null
}

cmd_start() {
    if is_running; then
        echo "already running (pid=$(cat "$PIDFILE"))"
        return 0
    fi
    if [ ! -x "$SCRIPT" ]; then
        echo "script not executable: $SCRIPT" >&2
        return 127
    fi
    # nohup detaches from the shell; setsid would be cleaner but toybox does
    # not guarantee it on every Android build.
    nohup "$SCRIPT" >/dev/null 2>&1 &
    pid=$!
    echo "$pid" >"$PIDFILE"
    echo "started pid=$pid"
}

cmd_stop() {
    if ! is_running; then
        echo "not running"
        rm -f "$PIDFILE"
        return 0
    fi
    pid=$(cat "$PIDFILE")
    kill "$pid" 2>/dev/null
    # Wait up to 5s, then SIGKILL.
    i=0
    while kill -0 "$pid" 2>/dev/null && [ $i -lt 5 ]; do
        sleep 1
        i=$((i + 1))
    done
    kill -0 "$pid" 2>/dev/null && kill -9 "$pid" 2>/dev/null
    rm -f "$PIDFILE"
    echo "stopped pid=$pid"
}

cmd_status() {
    if is_running; then
        echo "running pid=$(cat "$PIDFILE")"
    else
        echo "stopped"
    fi
    if [ -f "$LOG_FILE" ]; then
        echo "--- last 10 log lines ---"
        /system/bin/toybox tail -n 10 "$LOG_FILE"
    fi
}

case "${1:-}" in
    start)   cmd_start ;;
    stop)    cmd_stop ;;
    restart) cmd_stop; cmd_start ;;
    status)  cmd_status ;;
    *) echo "usage: $0 {start|stop|restart|status}" >&2; exit 2 ;;
esac