library/Zend/Validate/Barcode/UpcA.php

   1 <?php
   2
   3 /**
   4  * Zend Framework
   5  *
   6  * LICENSE
   7  *
   8  * This source file is subject to the new BSD license that is bundled
   9  * with this package in the file LICENSE.txt.
  10  * It is also available through the world-wide-web at this URL:
  11  * http://framework.zend.com/license/new-bsd
  12  * If you did not receive a copy of the license and are unable to
  13  * obtain it through the world-wide-web, please send an email
  14  * to license@zend.com so we can send you a copy immediately.
  15  *
  16  * @category   Zend
  17  * @package    Zend_Validate
  18  * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
  19  * @license    http://framework.zend.com/license/new-bsd     New BSD License
  20  * @version    $Id: UpcA.php 16223 2009-06-21 20:04:53Z thomas $
  21  */
  22
  23
  24 /**
  25  * @see Zend_Validate_Abstract
  26  */
  27 require_once 'Zend/Validate/Abstract.php';
  28
  29
  30 /**
  31  * @category   Zend
  32  * @package    Zend_Validate
  33  * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
  34  * @license    http://framework.zend.com/license/new-bsd     New BSD License
  35  */
  36 class Zend_Validate_Barcode_UpcA extends Zend_Validate_Abstract
  37 {
  38     /**
  39      * Validation failure message key for when the value is
  40      * an invalid barcode
  41      */
  42     const INVALID = 'invalid';
  43
  44     /**
  45      * Validation failure message key for when the value is
  46      * not 12 characters long
  47      */
  48     const INVALID_LENGTH = 'invalidLength';
  49
  50     /**
  51      * Validation failure message template definitions
  52      *
  53      * @var array
  54      */
  55     protected $_messageTemplates = array(
  56         self::INVALID        => "'%value%' is an invalid UPC-A barcode",
  57         self::INVALID_LENGTH => "'%value%' should be 12 characters",
  58     );
  59
  60     /**
  61      * Defined by Zend_Validate_Interface
  62      *
  63      * Returns true if and only if $value contains a valid barcode
  64      *
  65      * @param  string $value
  66      * @return boolean
  67      */
  68     public function isValid($value)
  69     {
  70         if (!is_string($value)) {
  71             $this->_error(self::INVALID);
  72             return false;
  73         }
  74
  75         $this->_setValue($value);
  76         if (strlen($value) !== 12) {
  77             $this->_error(self::INVALID_LENGTH);
  78             return false;
  79         }
  80
  81         $barcode = substr($value, 0, -1);
  82         $oddSum  = 0;
  83         $evenSum = 0;
  84
  85         for ($i = 0; $i < 11; $i++) {
  86             if ($i % 2 === 0) {
  87                 $oddSum += $barcode[$i] * 3;
  88             } elseif ($i % 2 === 1) {
  89                 $evenSum += $barcode[$i];
  90             }
  91         }
  92
  93         $calculation = ($oddSum + $evenSum) % 10;
  94         $checksum    = ($calculation === 0) ? 0 : 10 - $calculation;
  95
  96         if ($value[11] != $checksum) {
  97             $this->_error(self::INVALID);
  98             return false;
  99         }
 100
 101         return true;
 102     }
 103 }