#!/bin/bash

### BEGIN INIT INFO
# Provides:          noip2
# Required-Start:
# Required-Stop:
# Should-Start:      $network $syslog
# Should-Stop:       $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start and stop noip2
# Description:       noip2 manages dyn dns
### END INIT INFO

. /lib/lsb/init-functions

set -euf -o pipefail

NOIP_BIN='/usr/local/bin/noip2'
NOIP_NAME='noip2'
NOIP_OPTIONS="${NOIP_OPTIONS:-}"


function do_start()
{
    local rc=0

    log_daemon_msg 'Starting dynamic DNS client...'
    "${NOIP_BIN}" ${NOIP_OPTIONS} || rc=$?
    log_end_msg "${rc}"

    return ${rc}
}

function do_stop()
{
    local rc=0
    local pid="$(get_pid)"

    if [ -z "${pid}" ]; then
        log_warning_msg "${NOIP_NAME} not running"
        return
    fi

    log_daemon_msg 'Stopping dynamic DNS client...'
    "${NOIP_BIN}" -K "${pid}" \
        && waiting_for_stop "${pid}" \
        || rc=$?
    log_end_msg "${rc}"

    return ${rc}
}

function get_pid()
{
    "${NOIP_BIN}" -S 2>&1 \
        | grep '^Process' \
            | sed -E 's>^Process ([0-9]+),.+$>\1>' \
                || true
}

function waiting_for_stop()
{
    local pid="$1"
    local waiting_cycles=10

    while kill -0 ${pid} 2>/dev/null; do
        waiting_cycles="$[${waiting_cycles} - 1]"
        if [ "${waiting_cycles}" -lt 1 ]; then
            log_failure_msg "failed to stop ${NOIP_NAME} daemon"
            return 1
        fi
        sleep 0.5
    done
}


case "$1" in
    start)
        do_start
        ;;
    stop)
        do_stop
        ;;
    restart)
        do_stop
        do_start
        ;;
    *)
        echo "Usage: $0 {start|stop|restart}"
        exit 1
esac
exit 0