#!/bin/sh

# Allow only one instance
lockfile="/var/lock/${0##*/}.lock"
if ! lock -n "$lockfile"; then
	echo "Only one instance of $0 allowed."
	exit 1
fi
trap "lock -u \"$lockfile\"" INT TERM EXIT

. /usr/share/libubox/jshn.sh
. /lib/functions/fff/keyxchange
. /lib/functions/fff/network
. /lib/functions/fff/wireless
. /lib/functions/fff/timeserver
. /usr/lib/functions/fff/hoodfile


hoodfilelocal=/etc/hoodfile

rm -f "$hoodfiletmp"

# Gatewaycheck function
isGatewayAvailable() {
	if [ -n "$(batctl gwl -H)" ]; then
		return 0
	else
		return 1
	fi
}

# Ping test
hasInternet() {
	internetAddresses="keyserver.freifunk-franken.de heise.de"
	for addr in $internetAddresses; do
		ping -w5 -c3 "$addr" &>/dev/null && return 0
	done
	return 1
}

if [ -s "$hoodfilelocal" ]; then
	# remove webroot hoodfile to prevent offering local hoodfiles to neighbours
	rm -f "$hoodfilewww"

	cp "$hoodfilelocal" "$hoodfiletmp"
	echo "Use local hood file"
else
	# if internet is available, the hoodfile is downloaded from our keyserver
	if getKeyserverHoodfile "$hoodfiletmp"; then
		cp "$hoodfiletmp" "$hoodfilewww"

	# if no internet is available, but the node is already configured,
	# a gateway with the appropriate hoodfile should be available
	elif getGatewayHoodfile "$hoodfiletmp"; then
		cp "$hoodfiletmp" "$hoodfilewww"

	# no internet and no gateway available. the node is either unconfigured,
	# has lost connectivity or the hood is broken. Try to regain connectivity by
	# fetching hoodfiles from nearby nodes
	else
		rm -f "$hoodfileref" # delete this, so interfaces are recreated if reconnect with unchanged hood file takes place
		rm -f "$hoodfilewww" # delete this, so wrong hood file is not broadcasted anymore

		uci -q del "system.@system[0].hood"
		uci -q del "system.@system[0].hoodid"
		uci commit system
		reload_config

		sleep 30 # Wait for the config AP, which may be created at the same time as this script has started

		getEthernetHoodfile "$hoodfiletmp" || getWirelessHoodfile "$hoodfiletmp"
	fi
fi

if [ -s "$hoodfiletmp" ]; then

	# we get a json file in this format: 
	# https://pw.freifunk-franken.de/patch/205/
	# but without signature, every hood file we get is valid!

	sumnew=$(sha256sum "$hoodfiletmp" 2>/dev/null | cut -f1 -d " ")
	sumold=$(sha256sum "$hoodfileref" 2>/dev/null | cut -f1 -d " ")

	json_load "$(cat "$hoodfiletmp")"

	if [ "$sumnew" != "$sumold" ] ; then
		echo "New file detected, we reconfigure the Node";

		json_select hood

		json_get_var hood name
		json_get_var hoodid id
		[ -n "$mesh_id" ] || json_get_var mesh_id mesh_id
		[ -n "$mesh_bssid" ] || json_get_var mesh_bssid mesh_bssid
		[ -n "$mesh_essid" ] || json_get_var mesh_essid mesh_essid
		[ -n "$essid" ] || json_get_var essid essid
		json_get_var ntpip ntp_ip
		[ -n "$chan2ghz" ] || json_get_var chan2ghz channel2
		[ -n "$mesh_type2" ] || json_get_var mesh_type2 mesh_type2
		[ -n "$chan5ghz" ] || json_get_var chan5ghz channel5
		[ -n "$mesh_type5" ] || json_get_var mesh_type5 mesh_type5
		# Additional parameters may be activated in future versions
		#json_get_var mode2 mode2
		#json_get_var mode5 mode5
		#json_get_var protocol protocol
		
		json_select ".." # back to root
		
		if [ -z "$chan2ghz" ] || [ -z "$chan5ghz" ] ; then
			# If channel is missing, do nothing
			exit 0
		fi

		echo "Setting hood name: $hood (ID $hoodid)"
		uci set "system.@system[0].hood=$hood"
		uci set "system.@system[0].hoodid=$hoodid"
		uci commit system

		for radio in $(wifiListRadio); do
			freq="$(wifiGetFreq $radio)"

			if [ "$freq" = "5" ]; then
				uci set wireless.${radio}.channel="$chan5ghz"
				mesh_type="$mesh_type5"
			elif [ "$freq" = "2" ]; then
				uci set wireless.${radio}.channel="$chan2ghz"
				mesh_type="$mesh_type2"
			fi

			# Disable wXconfigap
			uci set wireless.w${freq}configap.disabled='1'

			# Configure wXap
			uci set wireless.w${freq}ap.ssid="$essid"
			uci set wireless.w${freq}ap.disabled='0'

			# Configure 802.11s mesh if type = "802.11s"
			if [ "$mesh_type" = "802.11s" ]; then
				uci set wireless.w${freq}mesh.mode='mesh'
				uci -q del wireless.w${freq}mesh.bssid
				uci -q del wireless.w${freq}mesh.ssid
				uci -q del wireless.w${freq}mesh.mcast_rate
				uci set wireless.w${freq}mesh.mesh_id="$mesh_id"
				uci set wireless.w${freq}mesh.mesh_fwding='0'
				uci set wireless.w${freq}mesh.disabled='0'
			# Configure IBSS mesh if type = "ibss"
			elif [ "$mesh_type" = "ibss" ]; then
				uci set wireless.w${freq}mesh.mode='adhoc'
				uci -q del wireless.w${freq}mesh.mesh_id
				uci -q del wireless.w${freq}mesh.mesh_fwding
				uci set wireless.w${freq}mesh.bssid="$mesh_bssid"
				uci set wireless.w${freq}mesh.ssid="$mesh_essid"
				uci set wireless.w${freq}mesh.mcast_rate='6000'
				uci set wireless.w${freq}mesh.disabled='0'
			# Disable mesh by setting no mesh_type
			else
				uci set wireless.w${freq}mesh.disabled='1'
			fi
		done

		uci commit wireless
		echo "Reloading wifi"
		reload_config

		oldntp="$(uci -q get system.ntp.server)"
		newntp="${ntpip}" # requires routable address, no link-local
		[ "$newntp" = "$oldntp" ] || setTimeserver "${newntp}" # only rewrite if changed

		# copy the file to webroot so that other mesh routers can download it;
		# copy only after all other steps so IF can be reentered if something goes wrong
		cp "$hoodfiletmp" "$hoodfileref"

		# This is a workaround to enable alfred on devices which do not see a configap during initial setup
		/etc/init.d/alfred restart
	else
		echo "We have no new file. We do nothing. We try it again in 5 minutes...";
	fi
	
	# and now we get to vpn-select script and load VPNs directly from /tmp/keyxchangev2data
	
	if hasInternet ; then
		/usr/sbin/vpn-select "$hoodfiletmp"
	else
		/usr/sbin/vpn-stop
	fi

	# now we load the prefix from the hoodfile and set this to br-client
	json_select network
	json_get_var prefix ula_prefix
	# Set $prefix::MAC as IP
	if [ -n "$prefix" ] ; then
		prefix="$(echo "$prefix" | sed -e 's,\\,,')"
		mac="$(cat "/sys/class/net/br-client/address")"
		addr="$(ipMacAssemble "$prefix" "$mac")"
		addr="$(ipTidyColon "$addr")"
		addr_eui="$(ipEUIAssemble "$prefix" "$mac")"
		addr_eui="$(ipTidyColon "$addr_eui")"
		for ip in $(ip -6 addr show dev br-client | grep inet6 | grep -v -e " $addr" -e " $addr_eui" -e " fe80::" -e " fdff::" | cut -f6 -d " "); do
			ip -6 addr del "$ip" dev br-client
		done
		if ! ( ip -6 addr show dev br-client | grep -q "$addr" ) ; then
			ip -6 addr add "$addr" dev br-client
			echo "Set ULA address to br-client: $addr"
		else
			echo "Address already set."
		fi
		# Set $prefix::link-local as IP
		if ! ( ip -6 addr show dev br-client | grep -q "$addr_eui" ) ; then
			ip -6 addr add "$addr_eui" dev br-client
			echo "Set ULA EUI-64 address to br-client: $addr_eui"
		else
			echo "Address already set."
		fi
		if ! ( ip -6 route show dev br-client | grep -q "fc00::" ) ; then
			ip -6 route add fc00::/7 via fe80::1 dev br-client
			echo "Set ULA route to br-client."
		else
			echo "Route already set."
		fi
	fi
	json_select ".." # back to root
else
	echo "We haven't got a file. We do nothing. We try it again in 5 minutes...";
	exit 0
fi

# Hidden AP check
if [ -s "$hoodfilewww" ] && isGatewayAvailable; then
	needwifi="0"
	for radio in $(wifiListRadio); do
		freq="$(wifiGetFreq $radio)"

		# Break: wXconfig is up
		[ "$(uci get "wireless.w${freq}configap.disabled")" = "0" ] && continue
		# Break: No mesh interface
		[ "$(uci get "wireless.w${freq}mesh.disabled")" = "0" ] || continue

		# Enable configap
		uci set wireless.w${freq}configap.disabled='0'
		uci commit wireless
		needwifi="1"
	done

	if [ "$needwifi" = "1" ]; then
		reload_config
		sleep 10
	fi
fi