<?php
/*************************  
  Copyright (c) 2004-2010 TinyWebGallery
  written by Michael Dempfle
 
  This program is free software; you can redistribute it and/or modify 
  it under the terms of the TinyWebGallery license (based on 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. 
  See license.txt for details.
 
  TWG version: 1.8
 
  $Date: 2009-06-17 22:57:10 +0200 (Mi, 17 Jun 2009) $
  $Revision: 73 $
**********************************************/

defined('_VALID_TWG') or die('Direct Access to this location is not allowed.');

function cryptEmail($email, $pos)
{
	global $encrypt_emails_key;
	// we test if the crypt key is o.k.!
	global $encrypt_emails;

	if ($encrypt_emails) {
		for ($i = 0; $i < strlen($encrypt_emails_key); $i++) {
			if (ord($encrypt_emails_key{$i}) > 127) {
				if ($pos == 0) {
					echo "The crypt key at position " . $i . " is not valid - please change the key in the configuration!";
				}
				return $email;
			}
		}
		// we use every single char and add the corresponding char of the security string!
		// we could check if the website do exists!
		$pos = $pos * 20;
		$codedemail = "";
		$keylen = strlen($encrypt_emails_key);
		for ($i = 0; $i < strlen($email); $i++) {
			$codedemail .= chr(ord($email{$i}) + ord($encrypt_emails_key{  (($pos + $i) % $keylen) }));
		}
		return $codedemail;
	} else {
		return $email;
	}
}

/*
the position is important . it tells which part of the crypt key is used!
*/
function decryptEmail($email , $pos)
{
	global $encrypt_emails_key;
	global $encrypt_emails;

	if ($encrypt_emails) {
		for ($i = 0; $i < strlen($encrypt_emails_key); $i++) {
			if (ord($encrypt_emails_key{$i}) > 127) {
				if ($pos == 0) {
					echo "The crypt key at position " . $i . " is not valid - please change the key in the configuration!";
				}
				return $email;
			}
		}
		$pos = $pos * 20;
		$codedemail = "";
		$keylen = strlen($encrypt_emails_key);
		for ($i = 0; $i < strlen($email); $i++) {
			$codedemail .= chr(ord($email{$i}) - ord($encrypt_emails_key{  (($pos + $i) % $keylen) }));
		}
		return $codedemail;
	} else {
		return $email;
	}
}

function testEmailDomain($email)
{
	global $test_email_by_checking_url;

	if ($test_email_by_checking_url)
		$handle = @fopen ("http://www.google.de/", "r");
	if ($handle == false) {
		// no connection - we skip the real test
		return true;
	} else {
		// we do the test!
		$domain = "http://www." . substr(strstr($email, '@'), 1);
		$handle = @fopen ($domain, "r");
		if ($handle == false) {
			// no connection - we skip the real test
			return false;
		}
	}
	// email domain is good :)
	return true;
}

?>