#!/bin/bash
# vim: set filetype=sh:
#
# Necessary environment variables:
# INITD=true, NAME, ACTION, PIDFILE, SERVER_BASENAME, SERVER_JAR, SERVER_PREPARE_STOP_CMD
#
# Optional environment variables:
# SERVER_OPTS, SERVER_JAVA_OPTS, SERVER_PREPARE_OPTS, SERVER_PREPARE_JAVA_OPTS, SERVER_BLOCK_BEFORE_START

einfo() {
	echo " * $*"
}

eerror() {
	echo " * ERROR: $*" >&2
}

die() {
	eerror "$*"
	exit 1
}

# Invocation protection
[[ $INITD == true ]] \
	|| die "Do not call $SERVER_BASENAME directly! Use /etc/init.d/$SERVER_BASENAME"

# Find JAVA_HOME
export JAVA_HOME="$(java-config --jre-home)"

# Disable spigot outdated messages
export IReallyKnowWhatIAmDoingISwear=1

exec_fork() {
	setsid "$@" &
}

MAX_SECONDS_WAIT=300
wait_for_pidfile_to_disappear() {
	# Wait for pidfile to disappear
	local seconds_waited=0
	while [[ $seconds_waited -lt $MAX_SECONDS_WAIT ]] ; do
		[[ -e $PIDFILE ]] || break
		sleep 1
		((++seconds_waited))
	done

	[[ $seconds_waited -lt $MAX_SECONDS_WAIT ]]
}

# Prepare TMUX command
TMUX_SOCKET="/var/lib/$SERVER_BASENAME/tmux/$NAME"
TMUX_EXEC="/usr/bin/tmux -2 -f /etc/tmux.conf -S $TMUX_SOCKET set -g default-shell /bin/bash ; "

BLOCK_FILE="/var/run/$SERVER_BASENAME/block/$NAME"

case "$ACTION" in
	"--prepare")
		# Preparing means starting the server once, then stopping it immediately.
		[[ ! -e sublime-local.conf ]] && install --mode=600 --owner=sublime /usr/share/sublime/sublime-local.conf .
		echo -e "$SERVER_PREPARE_STOP_CMD" | java $SERVER_PREPARE_JAVA_OPTS -jar $SERVER_JAR $SERVER_PREPARE_OPTS \
			|| die "Server returned unsuccessful status while preparing files"
		exit 0
		;;

	"--attach")
		$TMUX_EXEC attach-session
		;;

	"--stop")
		einfo "Please be patient, stopping the server can take some time (up to $MAX_SECONDS_WAIT seconds)."

		# Kill the tmux server
		$TMUX_EXEC kill-server 2>/dev/null

		wait_for_pidfile_to_disappear \
			|| eerror "Pidfile still existent after $MAX_SECONDS_WAIT seconds. Forcefully stopping the server."
		true
		;;

	"--start")
		$TMUX_EXEC kill-server 2>/dev/null
		wait_for_pidfile_to_disappear

		if [[ $SERVER_BLOCK_BEFORE_START == yes ]] ; then
			exec_fork $TMUX_EXEC new-session -d \
				loop --pidfile "$PIDFILE" \
					chain --delimiter='&&' \
						block -v --file "$BLOCK_FILE" '&&' \
						java $SERVER_JAVA_OPTS -jar $SERVER_JAR $SERVER_OPTS
		else
			exec_fork $TMUX_EXEC new-session -d \
				loop --pidfile "$PIDFILE" \
					java $SERVER_JAVA_OPTS -jar $SERVER_JAR $SERVER_OPTS
		fi
		;;

	*)
		die "Invalid usage"
		;;
esac