#!/bin/bash

### BEGIN INIT INFO
# Provides:          cloudstack-usage
# Required-Start:    $network $local_fs
# Required-Stop:     $network $local_fs
# Default-Start:     3 4 5
# Default-Stop:      0 1 2 6
# Short-Description: Start/stop Apache CloudStack Usage Monitor
# Description: This scripts Starts/Stops the Apache CloudStack Usage Monitor
##  The CloudStack Usage Monitor is a part of the Apache CloudStack project and is used
##  for storing usage statistics from instances.
## JSVC (Java daemonizing) is used for starting and stopping the usage monitor.
### END INIT INFO

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

. /lib/lsb/init-functions

SHORTNAME="cloudstack-usage"
PIDFILE=/var/run/"$SHORTNAME".pid
PROGNAME="CloudStack Usage Monitor"
CLASS="com.cloud.usage.UsageServer"
PROG="jsvc"
DAEMON="/usr/bin/jsvc"

unset OPTIONS
[ -r /etc/default/"$SHORTNAME" ] && source /etc/default/"$SHORTNAME"

setJavaHome() {
  # use $JAVA_HOME if defined
  if [ -n "$JAVA_HOME" ] ; then
    return
  fi

  # try java first
  java=$(which java 2>/dev/null || :)

  # try javac if java is not found
  if [ -z "$java" ] ; then
    java=$(which javac 2>/dev/null || :)
  fi

  if [ -n "$java" ] ; then
    JAVA_HOME=$(dirname $(dirname $(readlink -e $java)))
    export JAVA_HOME
    return
  fi

  # If everything has failed, try hardcoded paths
  # The first existing directory is used for JAVA_HOME (if JAVA_HOME is not defined in $DEFAULT)
  JDK_DIRS="/usr/lib/jvm/java-8-openjdk-amd64 /usr/lib/jvm/java-8-openjdk-i386 /usr/lib/jvm/java-8-oracle /usr/lib/jvm/java-8-openjdk"
  for jdir in $JDK_DIRS; do
    if [ -r "$jdir/bin/java" -a -z "${JAVA_HOME}" ]; then
      JAVA_HOME="$jdir"
      export JAVA_HOME
      return
    fi
  done

  # didnt find java home. exiting with error
  exit 1
}

setJavaHome

UCP=`ls /usr/share/cloudstack-usage/lib/*.jar | tr '\n' ':' | sed s'/.$//'`
PCP=`ls /usr/share/cloudstack-usage/plugins/*.jar 2>/dev/null | tr '\n' ':' | sed s'/.$//'`

# We need to append the JSVC daemon JAR to the classpath
# AgentShell implements the JSVC daemon methods
export CLASSPATH="/usr/share/java/commons-daemon.jar:/usr/share/java/mysql-connector-java.jar:$UCP:$PCP:/etc/cloudstack/usage"

start() {
    if [ -s "$PIDFILE" ] && kill -0 $(cat "$PIDFILE") >/dev/null 2>&1; then
        log_daemon_msg "$PROGNAME apparently already running"
        log_end_msg 0
        exit 0
    fi

    log_daemon_msg "Starting $PROGNAME" "$SHORTNAME"
    if hostname --fqdn >/dev/null 2>&1 ; then
        true
    else
        log_failure_msg "The host name does not resolve properly to an IP address. Cannot start $PROGNAME"
        log_end_msg 1
        exit 1
    fi

    if start_daemon -p $PIDFILE $DAEMON -home "$JAVA_HOME" -cp "$CLASSPATH" -pidfile "$PIDFILE" -outfile SYSLOG -errfile SYSLOG -Dpid=$$ $CLASS
        RETVAL=$?
    then
        rc=0
        sleep 1
        if ! kill -0 $(cat "$PIDFILE") >/dev/null 2>&1; then
            log_failure_msg "$PROG failed to start"
            rc=1
        fi
    else
        rc=1
    fi

    if [ $rc -eq 0 ]; then
        log_end_msg 0
    else
        log_end_msg 1
        rm -f "$PIDFILE"
    fi
}

stop() {
    log_daemon_msg "Stopping $PROGNAME" "$SHORTNAME"
    killproc -p $PIDFILE $DAEMON
    log_end_msg $?
    rm -f "$PIDFILE"
}

case "$1" in
    start)
        start
        ;;
    stop)
        stop
        ;;
    status)
        status_of_proc -p "$PIDFILE" "$PROG" "$SHORTNAME"
        RETVAL=$?
        ;;
    restart | force-reload)
        stop
        sleep 3
        start
        ;;
    *)
    echo "Usage: $0 {start|stop|restart|force-reload|status}"
    RETVAL=3
esac

exit $RETVAL