#! /bin/bash
### BEGIN INIT INFO
# Provides:          crate
# Required-Start:    $network $remote_fs $named
# Required-Stop:     $network $remote_fs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Starts and stops CrateDB.
# Description:       CrateDB - The distributed database for the age of Docker
### END INIT INFO

PATH=/bin:/usr/bin:/sbin:/usr/sbin
NAME=crate
DEFAULT=/etc/default/$NAME

if [ `id -u` -ne 0 ]; then
	echo "You need root privileges to run this script"
	exit 1
fi


. /lib/lsb/init-functions

if [ -r /etc/default/rcS ]; then
	. /etc/default/rcS
fi

if ! (java -version 2>&1 | grep -q "1.8") then
    if (alternatives --display java | grep -q "1.8.0") then
        JAVA_HOME=$(alternatives --display java | grep "1.8.0" | head -n 1 | cut -d' ' -f 1 | sed 's/bin\/java//')
    else
        echo "CrateDB requires Java 8!"
        exit 1
    fi
fi

CRATE_HOME=/usr/share/crate
CRATE_USER=crate
CRATE_GROUP=crate

DAEMON=${CRATE_HOME}/bin/crate
PID_FILE=${PIDFILE-/var/run/${NAME}/${NAME}.pid}

CRATE_PATH_PID=$(dirname ${PID_FILE})
CRATE_PATH_LOG=${CRATE_PATH_LOG-/var/log/${NAME}}
CRATE_PATH_WORK=${CRATE_PATH_WORK-/tmp/${NAME}}
CRATE_PATH_CONF=${CRATE_PATH_CONF-/etc/${NAME}}

DAEMON_OPTS="-d -p ${PID_FILE} \
    -Des.path.conf=${CRATE_PATH_CONF} \
    -Des.path.home=${CRATE_HOME} \
    -Des.path.logs=${CRATE_PATH_LOG} \
    -Des.path.work=${CRATE_PATH_WORK}"

# These environment variables are passed over.
CRATE_MIN_MEM=${CRATE_MIN_MEM-256m}
CRATE_MAX_MEM=${CRATE_MAX_MEM-1g}
MAX_OPEN_FILES=65535
MAX_LOCKED_MEMORY=unlimited
CRATE_INCLUDE=${CRATE_INCLUDE-${CRATE_HOME}/bin/crate.in.sh}
JAVA_OPTS=-XX:+UseCompressedOops

# overwrite settings from default file
if [ -f "$DEFAULT" ]; then
	. "$DEFAULT"
fi

checkJava() {
	if [ -x "$JAVA_HOME/bin/java" ]; then
		JAVA="$JAVA_HOME/bin/java"
	else
		JAVA=`which java`
	fi

	if [ ! -x "$JAVA" ]; then
		log_pogress_msg "Could not find any executable java binary. Please install java in your PATH or set JAVA_HOME"
		exit 1
	fi
}

start() {
    checkJava

    log_daemon_msg $"Starting ${NAME}"
    mkdir -p "$CRATE_PATH_WORK" "$CRATE_PATH_LOG" "$CRATE_PATH_PID" && chown "$CRATE_USER":"$CRATE_GROUP" "$CRATE_PATH_WORK" "$CRATE_PATH_LOG" "$CRATE_PATH_PID"
    touch "$PID_FILE" && chown "$CRATE_USER":"$CRATE_GROUP" "$PID_FILE"
    pid=`pidofproc -p "$PID_FILE" $NAME`
	if [ -n "$pid" ] ; then
		log_begin_msg "Already running."
		log_end_msg 0
		exit 0
	fi

    export CRATE_HOME
    export CRATE_MIN_MEM
    export CRATE_MAX_MEM
    export JAVA_OPTS
    export JAVA_HOME
    start-stop-daemon --start -b --user $CRATE_USER -c $CRATE_USER --pidfile "$PID_FILE" --exec $DAEMON -- $DAEMON_OPTS
    log_end_msg $?
}

stop() {
    log_daemon_msg $"Stopping ${NAME}"
    if [ -f "$PID_FILE" ]; then
		start-stop-daemon --stop --pidfile "$PID_FILE" \
			--user "$CRATE_USER" \
			--retry=TERM/20/KILL/5 >/dev/null
		if [ $? -eq 1 ]; then
			log_progress_msg "$NAME is not running but pid file exists, cleaning up"
		elif [ $? -eq 3 ]; then
			PID="`cat $PID_FILE`"
			log_failure_msg "Failed to stop $NAME (pid $PID)"
			exit 1
		fi
		rm -f "$PID_FILE"
	else
		log_progress_msg "(not running)"
	fi
	log_end_msg 0
}

graceful_stop() {
    log_daemon_msg "Gracefully stopping ${NAME}"
    start-stop-daemon --stop --pidfile "$PID_FILE" --signal USR2
    if [ -f "$PID_FILE" ]; then
		start-stop-daemon --stop --pidfile "$PID_FILE" \
			--user "$CRATE_USER" \
			--signal USR2
		if [ $? -eq 1 ]; then
			log_progress_msg "$NAME is not running but pid file exists, cleaning up"
		elif [ $? -eq 3 ]; then
			PID="`cat $PID_FILE`"
			log_failure_msg "Failed to gracefully stop $NAME (pid $PID)"
			exit 1
		fi
		rm -f "$PID_FILE"
	else
		log_progress_msg "(not running)"
	fi
	log_end_msg 0
    RETVAL=$?
}

case "$1" in
    start)
        start
        ;;
    stop)
        stop
        ;;
    graceful-stop)
        graceful_stop
        ;;
    status)
        status_of_proc -p $PID_FILE $NAME $NAME && exit 0 || exit $?
        ;;
    restart|force-reload)
        if [ -f "$PID_FILE" ]; then
            $0 stop
            sleep 1
        fi
        $0 start
        ;;
    *)
        N=/etc/init.d/${NAME}
        log_success_msg "Usage: $N {start|stop|restart|force-reload}" >&2
        exit 1
        ;;
esac

exit 0
