#!/bin/sh
#
#                    PEtALS ESB administration script
#
# DESCRIPTION
# 
# The main function of this script is to start, suspend or stop the PEtALS
# ESB. These operations are all performed in a "robust" manner in order to
# hide some unexpected behaviors of the ESB when starting or stopping.
#
# NOTE
# This script should be simplified as soon as the problems with
# components lifecycle management are fixed
#############################################################################
#debug mode
#set -xv

if [ ! -d "$PETALS_HOME" ]
then	
	TARGET_DIRECTORY=`dirname $0`
	TARGET_DIRECTORY=`cd $TARGET_DIRECTORY;pwd`
	if [ ! -x "$TARGET_DIRECTORY"/setenv.sh ] 
	then
		echo "Cannot find $TARGET_DIRECTORY/setenv.sh script."
		echo "This file is required to start PEtALS."
		exit 1
	fi
else
	TARGET_DIRECTORY="$PETALS_HOME/bin"
fi

. "$TARGET_DIRECTORY"/setenv.sh

# Print the usage message
#############################################################################
print_usage() {
		cat - <<EOF >&2
Usage: $NAME {start|console|suspend|stop|status}

    start       Start $NAME in server mode
    console     Start $NAME in console mode
    debug       Start $NAME in debug mode
    stop        Stop $NAME without undeploying the services
    shutdown    Undeploy all the services, uninstall all the components and stop $NAME
    status      Print $NAME status

EOF
}


# Exit with an error message
#
# Arguments
#	$*	the error message
#############################################################################
die() {
	[ -z "$*" ] || echo "$NAME: ERROR: $*" >&2
	exit 1
}


# Exit and indicate success
#############################################################################
success() {
	echo "OK"
	exit 0
}


# Exit and indicates failure
#############################################################################
failure() {
	echo "FAILED"
	exit 1
}


# Exit and indicates success after an abnormal behavior
#############################################################################
passed() {
	echo "PASSED"
	exit 3
}


# Start the PEtALS JVM as a daemon process, output redirected to
# petals-out.log
#############################################################################
petals_daemon() {
	mkdir -p $PETALS_HOME/logs
	nohup $PETALS_EXEC $* > $PETALS_HOME/logs/petals-out.log 2>&1 &
}




# Print PID of PEtALS processes on STDOUT
#############################################################################
petals_pid() {
	ps -eo "%p|%c|%a" \
		| sed -ne 's:^ *\([0-9]*\)|java *|.*server\.jar.*$:\1:p'
}



# Print the current PEtALS status on STDOUT with the following meanings:
#	running   petals is running AND the lock file exists
#	stopped	  petals process not found AND the lock file does not exist
#	unknown	  the lock file exists while the java process terminated OR
#             the java process still exist while the lock file is not found
#
# Arguments
#	$1	the expected status (optional), status is not printed when provided
#
# Return
#	0 if the current status and the expected status are the same
#	1 otherwise
#############################################################################
petals_status() {
	lock="$PETALS_HOME/locked"
	pid="`petals_pid`"
	status="unknown"

	if [ -f "$lock" -a -d "/proc/$pid" -a ! -z "$pid" ]; then
		status="running"
	elif [ ! -f "$lock" -a -z "$pid" ]; then
		status="stopped"
	fi

	[ -z "$1" ] && echo "$status"
	test "$status" = "$1"
}



# Blocks execution until the given condition become true or the given timeout
# expires. The condition is polled every second.
#
# Arguments
#	$1	the condition expression
#	$2	the timeout in seconds
#############################################################################
petals_wait_for() {
	status="${1?}"
	timeout="${2:-"30"}"

	for tick in `yes | sed "${timeout}q"`; do
		petals_status "$1" && return 0
		sleep 1
		echo -n "."
	done 

	return 1
}


# Start PEtALS with the given options
#
# Arguments
#	$1	Description
#	$2	Expected status (running, stopped)
#	$3	Timeout in seconds
#	$4	Options for the JVM
#
#############################################################################
petals_action() {
	echo -n "$1 $NAME: "
	petals_status "$2" && return 0
	petals_daemon "$4"
	petals_wait_for "$2" $3
}


# Kill every PEtALS processes with the given signal
#
# Arguments
#	$1	the signal name or number (see kill -l)
#
#############################################################################
petals_kill() {
	sig="${1:-"TERM"}"
	petals_pid | xargs -r kill -$sig 2>&1 > /dev/null
	return 0
}


# Force petals to be stopped
#############################################################################
petals_force_stop() {
	petals_kill TERM
	if ! petals_wait_for "stopped" 30; then
		petals_kill KILL
		if petals_wait_for "stopped" 30; then
			rm -rf $PETALS_HOME/locked $PETALS_HOME/work/*
		fi
	fi
	petals_status "stopped"
}


# Force petals to be shutdowned
#############################################################################
petals_force_shutdown() {
	if petals_force_stop; then
		rm -f $PETALS_HOME/repository/system-state.xml
		rm -rf $PETALS_HOME/install/*
		rm -rf $PETALS_HOME/installed/*
		rm -rf $PETALS_HOME/repository/components/*
		rm -rf $PETALS_HOME/repository/service-assemblies/*
		rm -rf $PETALS_HOME/repository/shared-libraries/*
	fi
	petals_status "stopped"
}

	

#############################################################################
trap "die 'caught an interruption signal'" INT QUIT KILL TERM HUP

[ -d "$JAVA_HOME" ] || die "$NAME: JAVA_HOME: environment variable not set or directory not found"
[ -d "$PETALS_HOME" ] || die "$NAME: PETALS_HOME: environment variable not set or directory not found"

if [ $# -ne 1 ] ; then
	print_usage
	exit 2
fi

case "$1" in
start)
	if petals_action "Starting" "running" 600 "start"; then
		success
	else
		failure
	fi
	;;
debug)
	$PETALS_DEBUG_EXEC start
	
	;;
console)
	$PETALS_EXEC -console start
	;;	
stop)
	if petals_action "Stop" "stopped" 30 "stop"; then
		success
	elif petals_force_stop; then
		passed
	else
		failure
	fi
	;;
shutdown)
	if petals_action "Shutdown" "stopped" 30 "shutdown"; then
		success
	elif petals_force_shutdown; then
		passed
	else
		failure
	fi
	;;
status)
	case "`petals_status`" in
	running)
		echo "$NAME is RUNNING (pid `petals_pid`)"
		;;
	stopped)
		echo "$NAME is STOPPED"
		;;
	*)
		echo "$NAME status is UNKNOWN"
	esac
	;;
*)
	die "$1: unknown command"
esac


exit 0