#!/bin/sh /etc/rc.common

START=01

PIDFILE="/tmp/run/watchcat"

append_string() {
	local varname="$1"; local actual="${!varname}"; local add="$2"; local separator="${3:- }"
	new="${actual:+$actual$separator}$add"
	eval "$varname=\$new"
}

shutdown_now() {
	local forcedelay="$1"

	reboot &
	
	[ "$forcedelay" -ge 1 ] && {
		sleep $forcedelay

		echo b > /proc/sysrq-trigger # Will immediately reboot the system without syncing or unmounting your disks.
	}
}

watchcat_allways() {
	local period="$1"; local forcedelay="$2" 
	
	sleep $period && shutdown_now "$forcedelay"
}

watchcat_ping() {
	local period="$1"; local forcedelay="$2"; local pinghosts="$3"; local pingperiod="$4"
	
	time=$(cat /proc/uptime) && time=${time%%.*}
	last=$time

	while true
	do
		sleep $pingperiod
	
		time=$(cat /proc/uptime) && time=${time%%.*}
		
 		for host in "$pinghosts" 
		do
			if ping -c 1 "$host" &> /dev/null 
			then 
				last=$time
			else
				diff=$((time-last))
				logger -p daemon.info -t "watchcat[$$]" "no internet connectivity for $diff seconds. Reseting when reaching $period"	
			fi
		done

		diff=$((time-last))
		[ $diff -ge $period ] && shutdown_now "$forcedelay"
	
	done
} 

timetoseconds() {
	local time=$1
	unset seconds

	{ [ "$time" -ge 1 ] 2> /dev/null && seconds="$time"; } || \
	{ [ "${time%s}" -ge 1 ] 2> /dev/null && seconds="${time%s}"; } || \
	{ [ "${time%m}" -ge 1 ] 2> /dev/null && seconds=$((${time%m}*60)); } || \
	{ [ "${time%h}" -ge 1 ] 2> /dev/null && seconds=$((${time%h}*3600)); } || \
	{ [ "${time%d}" -ge 1 ] 2> /dev/null && seconds=$((${time%d}*86400)); }
}

load_watchcat() {
	config_get period	$1 period
	config_get mode		$1 mode		"allways"
	config_get pinghosts	$1 pinghosts	"8.8.8.8"
	config_get pingperiod	$1 pingperiod	"600"
	config_get forcedelay	$1 forcedelay	"0"

	error=""

	timetoseconds "$period"
	period="$seconds"
        [ "$period" -ge 1 ] \
		|| append_string "error" "period is not set or not recognized" "; "
        [ "$mode" = "allways" -o "$mode" = "ping" ] \
		|| append_string "error" "mode must be 'allways' or 'ping'" "; "
        [ -n "$pinghosts" -o "$mode" = "allways" ] \
		|| append_string "error" "pinghosts must be set in 'ping' mode" "; "
	timetoseconds "$pingperiod"
	pingperiod="$seconds"
	[ "$pingperiod" -l "$period" -o "$mode" = "allways" ] \
		|| append_string "error" "pingperiod is not recognized" "; "
	[ "$forcedelay" -ge 0 ] \
		|| append_string "error" "forcedelay must be a integer greater or equal than 0, where 0 means disabled" "; "

	[ -n "$error" ] && { logger -p user.err -t "watchcat" "reboot program $1 not started - $error"; return; }

	if [ "$mode" = "allways" ]
	then
		watchcat_allways "$period" "$forcedelay" &
	else
		watchcat_ping "$period" "$forcedelay" "$pinghosts" "$pingperiod" &
	fi

	echo $! >> "$PIDFILE".pids
	
	logger -p user.info -t "sshtunnel" "started tunnels to $server (pid=$!;retrydelay=$retrydelay)" 
}

stop() {
        if [ -f "$PIDFILE".pids ]
        then
                logger -p user.info -t "watchcat" "stopping all reboot programs"
                
                while read pid
                do
			kill $pid
		done < "$PIDFILE".pids

		rm "$PIDFILE".pids

                logger -p user.info -t "watchcat" "all reboot programs stopped"
        else
                logger -p user.info -t "watchcat" "no reboot programs running"
        fi
}

start() {
	[ -f "$PIDFILE".pids ] && stop
        
	config_load system
	if [ -n "$(uci show system.@watchcat[0])" ] # at least one watchcat section exists
	then        
		logger -p user.info -t "watchcat" "starting all reboot programs"
		config_foreach load_watchcat watchcat
		logger -p user.info -t "watchcat" "all reboot programs started"	
	else
		logger -p user.info -t "watchcat" "no reboot programs defined"
	fi
}