#!/bin/sh
# Copyright (C) 2018 Ycarus (Yannick Chabanois) <ycarus@zugaina.org>

while true; do
	if [ "$(uci -q get glorytun.vpn.enable)" = "1" ]; then
		iface=$(uci -q get glorytun.vpn.dev)
	elif [ "$(uci -q get mlvpn.general.enable)" = "1" ]; then
		iface=$(uci -q get mlvpn.general.interface_name)
	elif [ "$(uci -q get openvpn.omr.enabled)" = "1" ]; then
		iface=$(uci -q get openvpn.omr.dev)
	fi
	addr=$(ubus call network.interface.omrvpn status | jsonfilter -q -e '@["ipv4-address"][0].address' | tr -d "\n")
	if [ -d "/sys/class/net/$iface" ]; then
		[ -z "$addr" ] && [ -n "$iface" ] && addr=$(ip -4 addr show dev $iface | grep inet | awk '{print $2}' | cut -d/ -f1 | tr -d "\n")
		peer=$(ubus call network.interface.omrvpn status | jsonfilter -q -e '@.route[0].nexthop' | tr -d "\n")
		[ -z "$peer" ] && [ -n "$iface" ] && peer=$(ip -4 r list dev $iface | grep kernel | awk '/proto kernel/ {print $1}' | grep -v / | tr -d "\n")
		[ -n "$addr" ] && [ -n "$peer" ] && {
			if [ "$addr" != "$(uci -q get network.omr6in4.ipaddr)" ] || [ "$peer" != "$(uci -q get network.omr6in4.peeraddr)" ]; then
				logger -t "omr6in4" "Set network for OMR 6in4 to local $addr peer $peer"
				uci -q batch <<-EOF
					set network.omr6in4.ipaddr=$addr
					set network.omr6in4.peeraddr=$peer
				EOF
				uci -q commit network
				if [ -n "$(ip tunnel | grep omr6in4)" ]; then
					ip tunnel change "6in4-omr6in4" mode sit local ${addr} remote ${peer}
				else
					ifup omr6in4
				fi
			fi
		}
	fi
	sleep 10
done