#!/usr/bin/lua

function restart_tunneldigger()
	io.popen('logger -t tunneldigger-watchdog "Restarting Tunneldigger."')
	os.execute("/etc/init.d/tunneldigger restart")
end

function read_pid_file()
	local pid_file = io.open("/var/run/tunneldigger.mesh-vpn.pid", "r")
	if not pid_file then
		return nil
	end
	pid = pid_file:read("*l") 
	pid_file:close()
	return pid
end

function check_for_mesh_vpn_neighbours()
	local handle = io.popen("batctl o", 'r')
	if handle~=nil then
		for line in handle:lines() do
			if line:find('mesh%-vpn') then
				handle:close()
				return true
			end
		end
	end
	handle:close()
	return false
end

local uci = require('simple-uci').cursor()
if uci:get_bool('tunneldigger', 'mesh_vpn', 'enabled') then
	if io.popen("pgrep tunneldigger"):read("*l") ~= read_pid_file() then
		io.popen('logger -t tunneldigger-watchdog "Process-Pid does not match with pid-File."')
		restart_tunneldigger()
		return
	end
	if not check_for_mesh_vpn_neighbours() then
		io.popen('logger -t tunneldigger-watchdog "No vpn-mesh neighbours found."')
		restart_tunneldigger()
		return
	end
end