#!/usr/bin/perl -w

use strict;
use LWP::Simple;

#
# utilize zoneedit's program to edit website dns ip info.
# the current used ip for dns is stored in $ip_file, which
# is used to check against. If the current used dns ip is different
# from the current ip we have, update ip and $ip_file. otherwise do null.
#
# it works best with cron job to monitor your ip change and update it in time.
#

# file path to store the current used ip
my $ip_file = "/home/qiang/script/ip.txt";

# sites used to get your domain ip. 
my $checkip_1 = "http://dynamic.zoneedit.com/checkip.html";
my $checkip_2 = "http://whatismyip.com";

# the regex you used to match your ip on the site.
my $ipmatch_2 = qr(Your IP is );
my $ipmatch_1 = qr(Current IP Address: );

# lynx path
my $lynx = '/usr/local/bin/lynx';

# authentication info for zoneedit
my $uname = "uname";
my $pwd = "passwd";

# domains need to be updated
my $domain_1 = 'http://dynamic.zoneedit.com/auth/dynamic.html?host=www.easyya.com';
my $domain_2 = 'http://dynamic.zoneedit.com/auth/dynamic.html?host=easyya.com';

######################## no need to edit below from here ###################

my $old_ip = &get_old_ip;

my $new_ip = &get_current_ip;

# continue if current ip is different than the old one.
unless ($old_ip eq $new_ip) {
	my $code1 = `$lynx -source -auth=$uname:$pwd $domain_1`;
	my $code2 = `$lynx -source -auth=$uname:$pwd $domain_2`;
	print $new_ip," ",$code1," ",$code2,"\n";
	open F,">$ip_file" or die $!;
	print F $new_ip;
	close F;
}

sub get_old_ip {
	my $ip;
	if (-e $ip_file) {
		open F,$ip_file or die $!;
		$ip = <F>;
		chomp $ip;
		close F;
	} else {
		$ip = "1.2.3.4";
	}
	return $ip;
}

sub get_current_ip {
	my ($checkip,$ipmatch) = &_get_checkip_site;
	my $content = get($checkip);
	die "Couldn't get $checkip!" unless defined $content;
	my ($ip) = $content =~ /$ipmatch(\d+\.\d+.\d+\.\d+)/;
	return $ip;
}

sub _get_checkip_site {
	my $header = head($checkip_2);
	unless ($header) {
		return ($checkip_1,$ipmatch_1);
	}
	return ($checkip_2,$ipmatch_2);
}