#!/bin/sh

timeout=10
run_broker() {
	local interface="$1"
	local pubkey="$2"
	local remote="$3"
	local brokerport="$4"
	local port
	local interval=5

	localtime=$(date +%s)

	# sleeping on stdin keeps the sockets open in nc, allowing us to receive a
	# reply. Unfortunately this means all requests take $timeout seconds even
	# if the server is faster
	peer_reply="$( { echo '{"version":1, "pubkey":"'"$pubkey"'"}'; sleep $timeout; } | gluon-wan timeout $timeout nc "$remote" "$brokerport" | tail -n1)"

	if [[ "x$peer_reply" != "x" ]]; then
		port=$(jsonfilter -s "$peer_reply" -e "@.port")
		peer_time=$(jsonfilter -s "$peer_reply" -e "@.time")

		difference=0
		if [[ $peer_time -gt $localtime ]]; then
			difference=$((peer_time - localtime))
		else
			difference=$((localtime - peer_time))
		fi

		if [[ "x$peer_time" != "x" && $difference -gt 240 ]]; then
			# local clock differs a lot from the peer clock.
			# assuming ntp is working only when a tunnel is established we need to
			# set the clock to something in the proximity of the correct time.
			# Let's assume peer_time for now. ntpd will handle the rest
			formatted_time=$(date -d "@$peer_time" +%Y%m%d%H%M.%S)
			date -s "$formatted_time" >/dev/null
		fi

		if [[ -z $port ]]; then
			error=$(jsonfilter -s "$peer_reply" -e "@.error")
			if [[ -n $error ]]; then
				reason=$(jsonfilter -s "$peer_reply" -e "@.error.reason")
				ecode=$(jsonfilter -s "$peer_reply" -e "@.error.code")
				echo "received error [$ecode] from host $remote: $reason" >&2

				if [[ "$ecode" == "1" ]]; then
					echo FULL
					return 1
				fi
			fi
		fi
		echo "$port"
		return 0
	else
		echo "Received no reply from peer $remote" >&2
		echo "ERROR"
		return 255
	fi
}

run_broker "$1" "$2" "$3" "$4"