<?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

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

 */

/**

 * Zend_InfoCard_Xml_Element

 */

require_once 'Zend/InfoCard/Xml/Element.php';

/**

 * Represents a SecurityTokenReference XML block

 *

 * @category   Zend

 * @package    Zend_InfoCard

 * @subpackage Zend_InfoCard_Xml

 * @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_SecurityTokenReference extends Zend_InfoCard_Xml_Element

{

    /**

     * Base64 Binary Encoding URI

     */

    const ENCODING_BASE64BIN = 'http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0#Base64Binary';

    /**

     * Return an instance of the object based on the input XML

     *

     * @param string $xmlData The SecurityTokenReference XML Block

     * @return Zend_InfoCard_Xml_SecurityTokenReference

     * @throws Zend_InfoCard_Xml_Exception

     */

    static public function getInstance($xmlData)

    {

        if($xmlData instanceof Zend_InfoCard_Xml_Element) {

            $strXmlData = $xmlData->asXML();

        } else if (is_string($xmlData)) {

            $strXmlData = $xmlData;

        } else {

            throw new Zend_InfoCard_Xml_Exception("Invalid Data provided to create instance");

        }

        $sxe = simplexml_load_string($strXmlData);

        if($sxe->getName() != "SecurityTokenReference") {

            throw new Zend_InfoCard_Xml_Exception("Invalid XML Block provided for SecurityTokenReference");

        }

        return simplexml_load_string($strXmlData, "Zend_InfoCard_Xml_SecurityTokenReference");

    }

    /**

     * Return the Key Identifier XML Object

     *

     * @return Zend_InfoCard_Xml_Element

     * @throws Zend_InfoCard_Xml_Exception

     */

    protected function _getKeyIdentifier()

    {

        $this->registerXPathNamespace('o', 'http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd');

        list($keyident) = $this->xpath('//o:KeyIdentifier');

        if(!($keyident instanceof Zend_InfoCard_Xml_Element)) {

            throw new Zend_InfoCard_Xml_Exception("Failed to retrieve Key Identifier");

        }

        return $keyident;

    }

    /**

     * Return the Key URI identifying the thumbprint type used

     *

     * @return string The thumbprint type URI

     * @throws  Zend_InfoCard_Xml_Exception

     */

    public function getKeyThumbprintType()

    {

        $keyident = $this->_getKeyIdentifier();

        $dom = self::convertToDOM($keyident);

        if(!$dom->hasAttribute('ValueType')) {

            throw new Zend_InfoCard_Xml_Exception("Key Identifier did not provide a type for the value");

        }

        return $dom->getAttribute('ValueType');

    }

    /**

     * Return the thumbprint encoding type used as a URI

     *

     * @return string the URI of the thumbprint encoding used

     * @throws Zend_InfoCard_Xml_Exception

     */

    public function getKeyThumbprintEncodingType()

    {

        $keyident = $this->_getKeyIdentifier();

        $dom = self::convertToDOM($keyident);

        if(!$dom->hasAttribute('EncodingType')) {

            throw new Zend_InfoCard_Xml_Exception("Unable to determine the encoding type for the key identifier");

        }

        return $dom->getAttribute('EncodingType');

    }

    /**

     * Get the key reference data used to identify the public key

     *

     * @param bool $decode if true, will return a decoded version of the key

     * @return string the key reference thumbprint, either in binary or encoded form

     * @throws Zend_InfoCard_Xml_Exception

     */

    public function getKeyReference($decode = true)

    {

        $keyIdentifier = $this->_getKeyIdentifier();

        $dom = self::convertToDOM($keyIdentifier);

        $encoded = $dom->nodeValue;

        if(empty($encoded)) {

            throw new Zend_InfoCard_Xml_Exception("Could not find the Key Reference Encoded Value");

        }

        if($decode) {

            $decoded = "";

            switch($this->getKeyThumbprintEncodingType()) {

                case self::ENCODING_BASE64BIN:

                    if(version_compare(PHP_VERSION, "5.2.0", ">=")) {

                        $decoded = base64_decode($encoded, true);

                    } else {

                        $decoded = base64_decode($encoded);

                    }

                    break;

                default:

                    throw new Zend_InfoCard_Xml_Exception("Unknown Key Reference Encoding Type: {$this->getKeyThumbprintEncodingType()}");

            }

            if(!$decoded || empty($decoded)) {

                throw new Zend_InfoCard_Xml_Exception("Failed to decode key reference");

            }

            return $decoded;

        }

        return $encoded;

    }

}