<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Validate

 * @subpackage Sitemap

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Changefreq.php 22668 2010-07-25 14:50:46Z thomas $

 */

/**

 * @see Zend_Validate_Abstract

 */

require_once 'Zend/Validate/Abstract.php';

/**

 * Validates whether a given value is valid as a sitemap <changefreq> value

 *

 * @link       http://www.sitemaps.org/protocol.php Sitemaps XML format

 *

 * @category   Zend

 * @package    Zend_Validate

 * @subpackage Sitemap

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Validate_Sitemap_Changefreq extends Zend_Validate_Abstract

{

    /**

     * Validation key for not valid

     *

     */

    const NOT_VALID = 'sitemapChangefreqNotValid';

    const INVALID   = 'sitemapChangefreqInvalid';

    /**

     * Validation failure message template definitions

     *

     * @var array

     */

    protected $_messageTemplates = array(

        self::NOT_VALID => "'%value%' is no valid sitemap changefreq",

        self::INVALID   => "Invalid type given. String expected",

    );

    /**

     * Valid change frequencies

     *

     * @var array

     */

    protected $_changeFreqs = array(

        'always',  'hourly', 'daily', 'weekly',

        'monthly', 'yearly', 'never'

    );

    /**

     * Validates if a string is valid as a sitemap changefreq

     *

     * @link http://www.sitemaps.org/protocol.php#changefreqdef <changefreq>

     *

     * @param  string  $value  value to validate

     * @return boolean

     */

    public function isValid($value)

    {

        if (!is_string($value)) {

            $this->_error(self::INVALID);

            return false;

        }

        $this->_setValue($value);

        if (!is_string($value)) {

            return false;

        }

        if (!in_array($value, $this->_changeFreqs, true)) {

            $this->_error(self::NOT_VALID);

            return false;

        }

        return true;

    }

}