#!/usr/bin/env bash


get_child_pids() {
  if [[ -z "$1" ]]; then echo "get_child_pids:error: \$1 is empty " 1>&2 ; exit 1 ; fi
  local parent_pid=$1
  ps -o pid --no-headers --ppid $parent_pid
}

# Function to recursively get all descendant PIDs
get_descendant_pids() {
  if [[ -z "$1" ]]; then echo "get_descendant_pids:error: \$1 is empty " 1>&2 ; exit 1 ; fi
  local parent_pid=$1
  local child_pids=$(get_child_pids $parent_pid)
  for pid in $child_pids; do
    echo $pid
    get_descendant_pids $pid
  done
}

export LC_ALL=C
function qnd_waitpid()
(
    while ps -p $1 &> /dev/null
    do
	sleep 5
    done
)
cd /tmp

source /etc/smokeping/slave_config.conf || { printf "/etc/smokeping/slave_config.conf not found\n" ; exit 1; }
LOGFILE=${LOGFILE:-/var/log/smokeping-slave.log}
CACHEDIR=${CACHEDIR:-/var/lib/smokeping/slave-cache}
SLAVE_SECRET_PATH=${SLAVE_SECRET_PATH:-/etc/smokeping/slave_secret.conf}
SMOKEPING_USER=${SMOKEPING_USER:-smokeping}
if [[ "$MASTER_URL" == "" ]] ; then
    printf "Set MASTER_URL= in /etc/smokeping/slave_config.conf\n"
    exit 1
fi
if [[ ! -e "$SLAVE_SECRET_PATH" ]] ; then
    printf "set SLAVE_SECRET_PATH in /etc/smokeping/slave_config.conf\n"
fi
chmod a-rwx "$SLAVE_SECRET_PATH"
SMOKEPING_PIDFILE=/run/smokeping-slave.pid


start()
{
    cd /var/lib/smokeping/

    mkdir -p "$CACHEDIR"
    chown $SMOKEPING_USER $CACHEDIR

    touch "$LOGFILE"
    chown $SMOKEPING_USER "$LOGFILE"

    while true
    do
        /sbin/setcap 'CAP_NET_RAW+eip CAP_NET_ADMIN+eip'  /usr/sbin/fping
        printf "\nStarting smokeping: %s\n" "$(date +'%Y-%m-%dT%H:%M:%S')" >> "$LOGFILE"
        unset LC_ALL
        unset LC_COLLATE
        rm -rf "$CACHEDIR"/*.cache
        printf '\nMONITOR:%s New process\n' $(date +'%Y-%m-%dT%H:%M:%S') >> $LOGFILE

        /bin/su $SMOKEPING_USER -s/bin/bash -c "\
           /usr/bin/smokeping \
           --nodaemon \
           --master-url=$MASTER_URL\
           --cache-dir=$CACHEDIR  \
           --shared-secret=$SLAVE_SECRET_PATH \
           --logfile=$LOGFILE &>> $LOGFILE"
        sync
        sleep 1
#        qnd_waitpid $(cat "$CACHEDIR"/smokeping.pid)
        printf "MONITOR:Smokeping died: %s\n" "$(date +'%Y-%m-%dT%H:%M:%S')" | tee "$LOGFILE"
        sleep 5
    done & >/dev/null 2>&1
    WRAPPER_PID=$!
    echo "$WRAPPER_PID" > /run/smokeping-slave.pid
}

stop()
{
    printf "Killing smokeping slave.\n"

    child_pids=$(get_descendant_pids $(cat  "$SMOKEPING_PIDFILE"))

    printf "PIDS=%s" "$(cat "$SMOKEPING_PIDFILE") $child_pids"
    /bin/kill --timeout 3000 TERM --timeout 1000 KILL --signal QUIT $(cat "$SMOKEPING_PIDFILE") $child_pids
    
}


case "$1" in
  start)
    printf "case up\n"
    start
    exit "$?"
    ;;
  stop)
    printf "case down\n"
    stop
    exit "$?"
    ;;
  status)
    if [[ -e "$SMOKEPING_PIDFILE" && "" != $(cat  "$SMOKEPING_PIDFILE") ]] ; then
      pstree -s -p $(cat  "$SMOKEPING_PIDFILE")
    else
      printf "smokeping slave is not running or not running from this service.\n"
    fi
    ;;
  restart)
    if ! stop
    then
      exit "$?"
    fi
    if ! start
    then
      exit "$?"
    fi
    ;;
  *) printf "usage: {up,down,restart,status}\n"
esac