#!/bin/sh
#
# trigger-rcmp: Trigger remote commands
# Copyright (c)2014-2015 Alexander Barton (alex@barton.de)
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# Please read the file COPYING, README and AUTHORS for more information.
#

NAME="`basename "$0"`"
RCMD_D="/usr/local/etc/rcmd.d"

PATH="$PATH:/usr/local/sbin:/usr/sbin"

do_help() {
	echo "Usage: $0 [--no-wake|-n] <rcmd> [<rcmd> [...]]" >&2
	exit 2
}

do_rcmd() {
	SYSTEM="localhost"
	IFACE="eth0"
	CMD="uptime"
	TIMEOUT="300"
	SSH_CHECKS="6"
	WAKE_DELAY="10s"
	BOOT_DELAY="1m"
	SHUTDOWN_TIME="+10"

	. "$cnf"

	if [ $? -ne 0 ]; then
		echo "$NAME: failed to read \"$cnf\"!"
		return 2
	fi

	NAME="$NAME($1)"

	echo "$NAME: checking system \"$SYSTEM\" ..."
	fping -c1 -q "$SYSTEM" 2>/dev/null
	if [ $? -ne 0 ]; then
		if [ -n "$NO_WAKE" ]; then
			echo "$NAME: \"$SYSTEM\" seems to be down, skipping job."
			return 9
		fi

		echo "$NAME: \"$SYSTEM\" seems to be down, wake it up ..."
		etherwake -b -i "$IFACE" `echo "$SYSTEM" | cut -d'.' -f1`
		if [ $? -ne 0 ]; then
			echo "$NAME: failed to wake \"$SYSTEM\"!" >&2
			return 3
		fi
		echo "$NAME: waiting for \"$SYSTEM\" to respond ..."
		for i in `seq 1 $TIMEOUT`; do
			fping -c1 -q "$SYSTEM" 2>/dev/null
			[ $? -ne 0 ] || break
			sleep 1s
		done
		fping -c1 -q "$SYSTEM" 2>/dev/null
		if [ $? -ne 0 ]; then
			echo "$NAME: failed to wake \"$SYSTEM\"!" >&2
			return 4
		fi
		sleep "$WAKE_DELAY"
		rsys_was_running=0
	else
		echo "$NAME: \"$SYSTEM\" is already alive, ok."
		rsys_was_running=1
	fi

	for i in `seq 1 $SSH_CHECKS`; do
		echo "$NAME: checking SSH connection ($i/$SSH_CHECKS) ..."
		ssh -q -o "ServerAliveInterval 120" "$SYSTEM" true >/dev/null 2>&1 && break
		echo "$NAME: SSH on \"$SYSTEM\" not ready. Waiting ..."
		sleep 10s
	done
	echo "$NAME: ok, SSH seems to be available on \"$SYSTEM\"."

	if [ "$rsys_was_running" -eq 0 ]; then
		echo "$NAME: \"$SYSTEM\" just started up. Delaying actions for $BOOT_DELAY ..."
		sleep "$BOOT_DELAY"
	fi

	echo "$NAME: calling \"$CMD\" on \"$SYSTEM\" ..."
	echo

	ssh -q  -o "ServerAliveInterval 120" "$SYSTEM" "$CMD" </dev/null ; r=$?

	echo
	echo "$NAME: remote command ended with return code $r."
	sleep 2

	if [ "$rsys_was_running" -eq 0 ]; then
		rsys_users=`ssh -q "$SYSTEM" w | tail -n +3 | wc -l`
		if [ "$rsys_users" = "0" ]; then
			echo "$NAME: power off \"$SYSTEM\" again ..."
			ssh -q  -o "ServerAliveInterval 120" "$SYSTEM" "sync; shutdown -hP $SHUTDOWN_TIME" >/dev/null
			if [ $? -ne 0 ]; then
				echo "$NAME: failed to power off \"$SYSTEM\"!" >&2
				return 5
			fi
		else
			echo "$NAME: not shutting down \"$SYSTEM\", \c"
			[ $rsys_users -eq 1 ] \
				&& echo "there is 1 user logged in!" \
				|| echo "there are $rsys_users users logged in!"
		fi
	else
		echo "$NAME: \"$SYSTEM\" was already alive, not shutting down."
	fi
	[ $r -eq 0 ] && return 0 || return 1
}

# Defaults
NO_WAKE=

while [ $# -gt 0 ]; do
	case "$1" in
	  --no-wake|-n)
		NO_WAKE=1; ;;
	  --help|-*)
		do_help; ;;
	  *)
		break
	esac
	shift
done

[ $# -gt 0 ] || do_help

result=0
while [ $# -gt 0 ]; do
	cnf="$RCMD_D/$1"
	if [ ! -r "$cnf" ]; then
		echo "$NAME: can't read \"$cnf\"!"
		r=1
	else
		echo "$NAME: working on \"$1\" - `date "+%Y-%m-%d %H:%M:%S"`"
		do_rcmd "$1" ; r=$?
		echo "$NAME: done ($r) - `date "+%Y-%m-%d %H:%M:%S"`"
	fi
	[ $r -ne 0 ] && result=1
	shift
	[ $# -gt 0 ] && echo
done
exit $result