<?php

/**
 * This file is part of the Froxlor project.
 * Copyright (c) 2003-2009 the SysCP Team (see authors).
 * Copyright (c) 2010 the Froxlor Team (see authors).
 *
 * For the full copyright and license information, please view the COPYING
 * file that was distributed with this source code. You can also view the
 * COPYING file online at http://files.froxlor.org/misc/COPYING.txt
 *
 * @copyright  (c) the authors
 * @author     Florian Lippert <flo@syscp.org> (2003-2009)
 * @author     Froxlor team <team@froxlor.org> (2010-)
 * @license    GPLv2 http://files.froxlor.org/misc/COPYING.txt
 * @package    Functions
 *
 */

/**
 * Validates the given string by matching against the pattern, prints an error on failure and exits
 *
 * @param string $str the string to be tested (user input)
 * @param string the $fieldname to be used in error messages
 * @param string $pattern the regular expression to be used for testing
 * @param string language id for the error
 * @return string the clean string
 *
 * If the default pattern is used and the string does not match, we try to replace the
 * 'bad' values and log the action.
 *
 */

function validate($str, $fieldname, $pattern = '', $lng = '', $emptydefault = array()) {

	global $log, $theme;

	if (!is_array($emptydefault)) {
		$emptydefault_array = array(
			$emptydefault
		);
		unset($emptydefault);
		$emptydefault = $emptydefault_array;
		unset($emptydefault_array);
	}

	// Check if the $str is one of the values which represent the default for an 'empty' value
	if (is_array($emptydefault)
	   && !empty($emptydefault)
	   && in_array($str, $emptydefault)
	   && isset($emptydefault[0])
	) {
		return $emptydefault[0];
	}

	if ($pattern == '') {

		$pattern = '/^[^\r\n\t\f\0]*$/D';

		if (!preg_match($pattern, $str)) {
			// Allows letters a-z, digits, space (\\040), hyphen (\\-), underscore (\\_) and backslash (\\\\),
			// everything else is removed from the string.
			$allowed = "/[^a-z0-9\\040\\.\\-\\_\\\\]/i";
			$str = preg_replace($allowed, "", $str);
			$log->logAction(USR_ACTION, LOG_WARNING, "cleaned bad formatted string (" . $str . ")");
		}
	}

	if (preg_match($pattern, $str)) {
		return $str;
	}

	if ($lng == '') {
		$lng = 'stringformaterror';
	}

	standard_error($lng, $fieldname);
	exit;
}