#! /bin/bash

PASSWORD=""
DOMAIN=""
INTERFACE="eth0"
FILENAME="/etc/haproxy/haproxy.cfg"

usage(){
cat << EOF
usage: update-ipv6 [OPTIONS] -p [PASSWORD] -d [DOMAIN_NAME]
Dynamic DNS script helper that updates records in freedns.afraid.org if the IPV6 address has been changed.
	
Options:
  -f	Force update in record even if IP hasn't change
  --dry	Shows if the IP addres has changed without updating it 
  -i  Interface name default: eth0
  -F  Filename where to compare previous address default= /etc/haproxy/haproxy.cfg

EOF
exit 1
  
}

if [[ $# -lt 4 ]] ; 
then
  usage
fi

while [[ ! -z "$1" ]]; do
	case $1 in
		-p) 
			PASSWORD=$2
			shift 2;;
		-d) 
			DOMAIN=$2
			shift 2;;
	 	-f)	
			FORCE=true
			shift 1;;
		--dry)	
			DRY=true
			shift 1;;
		-i)	
			INTERFACE=$2
			shift 2;;
		*)
			echo $option
			usage;;
	esac
done

addresses=$(/usr/sbin/ifconfig $INTERFACE | grep 'inet6.*global>' | awk  '{ print $2 }'); 
GREAT=0
add=""
for address in $addresses; 
do 
	secs=$(/usr/sbin/ip addr show dev $INTERFACE | grep -A1 $address | grep -v $address | awk '{ print $2}')
	if [ $GREAT -gt ${secs/sec/} ] || [ $GREAT == 0 ];
	then
		GREAT=${secs/sec/}
		add=$address
	fi

done
echo $address
	if [[ $add ]] && [[ -z $(grep $add $FILENAME ) ]] ; then
		hadd=$(grep -o -m 1 'NAT1TO1=[^"]*' $FILENAME |  awk  'BEGIN {FS = "=" } ; { print $2 }');
		if [[ $DRY ]]; then
			echo "Address would change from $add to $hadd"
			exit 1;
		fi
                sed -i s/${hadd}/$add/ $FILENAME 
		echo curl --user "nextia365:$PASSWORD" -XPOST http://freedns.afraid.org/nic/update?hostname=$DOMAIN\&myip=$add
		curl --user "nextia365:$PASSWORD" -XPOST http://freedns.afraid.org/nic/update?hostname=$DOMAIN\&myip=$add
	else
		echo Unchanged
		if [[ $FORCE ]]; then
			curl --user "nextia365:$PASSWORD" -XPOST http://freedns.afraid.org/nic/update?hostname=$DOMAIN\&myip=$add
		fi
	fi
if [[ $DRY ]]; then
	echo "Address didn't change from $add"
	exit 1;
fi