repo_zf1/library/Zend/Validate/Barcode/Postnet.php

<?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
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id:$
 */

/**
 * @see Zend_Validate_Barcode_AdapterAbstract
 */
require_once 'Zend/Validate/Barcode/AdapterAbstract.php';

/**
 * @category   Zend
 * @package    Zend_Validate
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Validate_Barcode_Postnet extends Zend_Validate_Barcode_AdapterAbstract
{
    /**
     * Allowed barcode lengths
     * @var integer
     */
    protected $_length = array(6, 7, 10, 12);

    /**
     * Allowed barcode characters
     * @var string
     */
    protected $_characters = '0123456789';

    /**
     * Checksum function
     * @var string
     */
    protected $_checksum = '_postnet';

    /**
     * Validates the checksum ()
     * POSTNET implementation
     *
     * @param  string $value The barcode to validate
     * @return boolean
     */
    protected function _postnet($value)
    {
        $checksum = substr($value, -1, 1);
        $values   = str_split(substr($value, 0, -1));

        $check = 0;
        foreach($values as $row) {
            $check += $row;
        }

        $check %= 10;
        $check = 10 - $check;
        if ($check == $checksum) {
            return true;
        }

        return false;
    }
}