<?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_InfoCard

 * @subpackage Zend_InfoCard_Xml_Security

 * @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: Transform.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/**

 * A class to create a transform rule set based on XML URIs and then apply those rules

 * in the correct order to a given XML input

 *

 * @category   Zend

 * @package    Zend_InfoCard

 * @subpackage Zend_InfoCard_Xml_Security

 * @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_InfoCard_Xml_Security_Transform

{

    /**

     * A list of transforms to apply

     *

     * @var array

     */

    protected $_transformList = array();

    /**

     * Returns the name of the transform class based on a given URI

     *

     * @throws Zend_InfoCard_Xml_Security_Exception

     * @param string $uri The transform URI

     * @return string The transform implementation class name

     */

    protected function _findClassbyURI($uri)

    {

        switch($uri) {

            case 'http://www.w3.org/2000/09/xmldsig#enveloped-signature':

                return 'Zend_InfoCard_Xml_Security_Transform_EnvelopedSignature';

            case 'http://www.w3.org/2001/10/xml-exc-c14n#':

                return 'Zend_InfoCard_Xml_Security_Transform_XmlExcC14N';

            default:

                require_once 'Zend/InfoCard/Xml/Security/Exception.php';

                throw new Zend_InfoCard_Xml_Security_Exception("Unknown or Unsupported Transformation Requested");

        }

    }

    /**

     * Add a Transform URI to the list of transforms to perform

     *

     * @param string $uri The Transform URI

     * @return Zend_InfoCard_Xml_Security_Transform

     */

    public function addTransform($uri)

    {

        $class = $this->_findClassbyURI($uri);

        $this->_transformList[] = array('uri' => $uri,

                                        'class' => $class);

        return $this;

    }

    /**

     * Return the list of transforms to perform

     *

     * @return array The list of transforms

     */

    public function getTransformList()

    {

        return $this->_transformList;

    }

    /**

     * Apply the transforms in the transform list to the input XML document

     *

     * @param string $strXmlDocument The input XML

     * @return string The XML after the transformations have been applied

     */

    public function applyTransforms($strXmlDocument)

    {

        foreach($this->_transformList as $transform) {

            if (!class_exists($transform['class'])) {

                require_once 'Zend/Loader.php';

                Zend_Loader::loadClass($transform['class']);

            }

            $transformer = new $transform['class'];

            // We can't really test this check because it would require logic changes in the component itself

            // @codeCoverageIgnoreStart

            if(!($transformer instanceof Zend_InfoCard_Xml_Security_Transform_Interface)) {

                require_once 'Zend/InfoCard/Xml/Security/Exception.php';

                throw new Zend_InfoCard_Xml_Security_Exception("Transforms must implement the Transform Interface");

            }

            // @codeCoverageIgnoreEnd

            $strXmlDocument = $transformer->transform($strXmlDocument);

        }

        return $strXmlDocument;

    }

}