#!/bin/sh

###
 #
 # FreeWLAN Addons - http://www.freewlan.info
 #
 # This program is free software; you can redistribute it and/or
 # modify it under the terms of the GNU General Public License
 # as published by the Free Software Foundation; either version 2
 # of the License, or (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 # MA  02110-1301, USA
 #
 # http://www.gnu.org/copyleft/gpl.html
 #
###

. /etc/functions.sh

config_load dyndns
config_get enable dyndns enable
config_get user dyndns user
config_get pass dyndns pass
config_get url dyndns url

if enabled $enable && [ ! -f /tmp/dyndns.lock ]
then
	if [ ! -f /etc/config/ip.cache ]
	then
		echo '0.0.0.0'>/etc/config/ip.cache
	fi

	ip_now=$(expr "$(wget -O - http://checkip.dyndns.org 2> /dev/null)" : '.*[^0-9]\([0-9]*\.[0-9]*\.[0-9]*\.[0-9]*\)')
	if [ "$ip_now" = "" ]
	then
		exit 1
	fi
	
	date=`date +"%s"`
	date_last=`date -r /etc/config/ip.cache +"%s"`
	if [ `expr $date - $date_last` -lt 2505600 ]
	then
		ip_old=$(cat /etc/config/ip.cache)
		if [ "$ip_old" = "$ip_now" ]
		then
			exit 0 # IP not changed and 29 days havn't passed
		fi
	fi
	return="$(wget -q -O - http://$user:$pass@members.dyndns.org/nic/update\?system=dyndns\&hostname=$url 2> /dev/null | awk '{print $1}')"
	if [ "$return" = "good" ] || [ "$return" = "nochg" ]
	then
		echo "$ip_now">/etc/config/ip.cache
		exit 0
	else
		rm -f /etc/config/ip.cache
		if [ "$return" != "" ]
		then
			touch /tmp/dyndns.lock
		fi
		exit 1
	fi
else
	exit 0
fi