#!/bin/sh
#
# CopyLeft moon.cat
# This work is licensed under a Creative Commons Attribution 4.0 International License.
#
# Author: Rei Izumi - moon.cat - blog.moon.cat - 2017
#
#
IP_FILE='/scripts/IP.txt'

MAIL_TO=tu_email@domain.cat
#Name of the user sending the mail
MAIL_SENDER='Request IP <ip@domain.cat>'
MAIL_SUBJECT='New IP: '

#Check old IP
if [ -f "$IP_FILE" ]; then
	oldIP=`cat $IP_FILE`
else
	oldIP=
fi

#Retrieve actual IP
newIP=`wget http://checkip.dyndns.org/ -O - -o /dev/null | cut -d':' -f 2 | cut -d' ' -f 2 | cut -d'<' -f 1`

echo "Old IP: $oldIP"
echo "New IP: $newIP"

if [ "$newIP" != "$oldIP" ]; then
	printf "Old IP: $oldIP\nNew IP: $newIP" | mail -s "$MAIL_SUBJECT$newIP" -r "$MAIL_SENDER" $MAIL_TO
	echo $newIP > $IP_FILE
fi