# vim: set ft=sh noexpandtab tabstop=4 shiftwidth=4 softtabstop=4 :

SETROUTE=false
set_route() {
	local multipath_config interface_gw interface_if
	INTERFACE=$1
	PREVINTERFACE=$2
	multipath_config=$(uci -q get "network.$INTERFACE.multipath" || echo "off")
	interface_if=$(uci -q get "network.$INTERFACE.ifname")
	multipath_current_config=$(multipath $interface_if | grep deactivated)
	if [ "$multipath_config" != "off" ] && [ "$SETROUTE" != true ] && [ "$INTERFACE" != "$PREVINTERFACE" ] && [ "$multipath_current_config" = "" ]; then
	#if [ "$multipath_config" != "off" ] && [ "$SETROUTE" != true ]; then
	#if [ "$multipath_config" != "off" ] && [ "$INTERFACE" != "$PREVINTERFACE" ] && [ "$SETROUTE" != true ]; then
		interface_gw=$(uci -q get "network.$INTERFACE.gateway")
		if [ -z $interface_gw ]; then
			$interface_gw=$(ubus call network.interface.$INTERFACE status | jsonfilter -e '@.route[0].nexthop' | tr -d "\n")
		fi
		if [ -z $interface_gw ]; then
			$interface_gw=$(ubus call network.interface.$INTERFACE status | jsonfilter -e '@.inactive.route[0].nexthop' | tr -d "\n")
		fi
		if [ "$interface_gw" != "" ]; then
			_log "Replace default route by $interface_gw dev $interface_if"
			ip route replace default scope global nexthop via $interface_gw dev $interface_if && SETROUTE=true
		fi
	fi
}

set_ss_route() {
	local server_ip
	config_get server_ip $1 server
	if [ "$server_ip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] && [ "$(ip route show dev $OMR_TRACKER_DEVICE | grep $server_ip | grep $OMR_TRACKER_DEVICE_GATEWAY)" = "" ]; then
		_log "Set server route via $OMR_TRACKER_DEVICE"
		ip route replace $server_ip via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE
	fi
}

del_ss_route() {
	local server_ip
	config_get server_ip $1 server
	if [ "$server_ip" != "" ] && [ "$OMR_TRACKER_DEVICE_GATEWAY" != "" ] &&  [ "$(ip route show dev $OMR_TRACKER_DEVICE | grep $server_ip | grep $OMR_TRACKER_DEVICE_GATEWAY)" != "" ]; then
		_log "Remove server route via $OMR_TRACKER_DEVICE"
		ip route delete $server_ip via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE
	fi
}

sleep `expr $RANDOM % 10`

# Get the current multipath status
multipath_status="off"
case "$(multipath "$OMR_TRACKER_DEVICE")" in
	*default*)      multipath_status="on"       ;;
	*backup*)       multipath_status="backup"   ;;
	*handover*)     multipath_status="handover" ;;
esac

default_gw=$(ip route show default | grep -v metric | awk '/default/ {print $3}')
#current_interface_gw=$(uci -q get "network.$OMR_TRACKER_INTERFACE.gateway")

# An interface in error will never be used in MPTCP
if [ "$OMR_TRACKER_STATUS" = "ERROR" ]; then
	#[ "$multipath_status" = "off" ] && exit 0
	#_log "$OMR_TRACKER_DEVICE switched off"
	multipath "$OMR_TRACKER_DEVICE" off
	if [ "$default_gw" = "$OMR_TRACKER_DEVICE_GATEWAY" ] || [ "$default_gw" = "" ]; then
		config_load network
		config_foreach set_route interface $OMR_TRACKER_INTERFACE
	fi
	config_load shadowsocks-libev
	config_foreach del_ss_route server
	exit 0
fi

if [ "$OMR_TRACKER_INTERFACE" = "glorytun" ]; then
	if [ "$default_gw" != "$OMR_TRACKER_DEVICE_GATEWAY" ] || [ "$default_gw" = "" ]; then
		_log "Tunnel up : Replace default route by $current_interface_gw dev $OMR_TRACKER_DEVICE"
		ip route replace default scope global nexthop via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE
	fi
	exit 0
fi

multipath_config=$(uci -q get "network.$OMR_TRACKER_INTERFACE.multipath" || echo "off")
if [ "$multipath_config" = "master" ]; then
	if [ "$default_gw" != "$OMR_TRACKER_DEVICE_GATEWAY" ] || [ "$default_gw" = "" ]; then
		if [ "$(ip route show default | grep -v metric | awk '/default/ {print $5}' | grep tun)" = "" ]; then
			_log "Master up : Replace default route by $current_interface_gw dev $OMR_TRACKER_DEVICE"
			ip route replace default scope global nexthop via $OMR_TRACKER_DEVICE_GATEWAY dev $OMR_TRACKER_DEVICE
		else
			config_load shadowsocks-libev
			config_foreach set_ss_route server
		fi
	fi
	multipath_config="on"
fi
[ "$multipath_config" = "master" ] && [ "$multipath_status" = "on" ] && exit 0
[ "$multipath_status" = "$multipath_config" ] && exit 0
_log "Multipath $OMR_TRACKER_DEVICE switched to $multipath_config"

multipath "$OMR_TRACKER_DEVICE" "$multipath_config"