1<?php
2// (c) Copyright by authors of the Tiki Wiki CMS Groupware Project
3//
4// All Rights Reserved. See copyright.txt for details and a complete list of authors.
5// Licensed under the GNU LESSER GENERAL PUBLIC LICENSE. See license.txt for details.
6// $Id$
7
8/**
9 * Class TikiFilter_Lang
10 *
11 * Filters for valid language values
12 */
13class TikiFilter_Lang implements Zend\Filter\FilterInterface
14{
15	/**
16	 * Based on is_valid_language() method in lib/language/Language.php. The Language class isn't used here because
17	 * necessary classes/definitions are not available at the point the filter is used in the installer
18	 *
19	 * @param mixed $input
20	 * @return mixed|string
21	 */
22	function filter($input)
23	{
24		$filtered = preg_filter('/^[a-zA-Z-_]*$/', '$0', $input);
25		return $filtered && file_exists('lang/' . $filtered . '/language.php') ? $filtered : '';
26	}
27}
28