<?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_Gdata

 * @subpackage Gdata

 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)

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

 * @version    $Id: AuthSub.php 24593 2012-01-05 20:35:02Z matthew $

 */

/**

 * Zend_Gdata_HttpClient

 */

require_once 'Zend/Gdata/HttpClient.php';

/**

 * Zend_Version

 */

require_once 'Zend/Version.php';

/**

 * Wrapper around Zend_Http_Client to facilitate Google's "Account Authentication

 * Proxy for Web-Based Applications".

 *

 * @see http://code.google.com/apis/accounts/AuthForWebApps.html

 *

 * @category   Zend

 * @package    Zend_Gdata

 * @subpackage Gdata

 * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)

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

 */

class Zend_Gdata_AuthSub

{

    const AUTHSUB_REQUEST_URI      = 'https://www.google.com/accounts/AuthSubRequest';

    const AUTHSUB_SESSION_TOKEN_URI = 'https://www.google.com/accounts/AuthSubSessionToken';

    const AUTHSUB_REVOKE_TOKEN_URI  = 'https://www.google.com/accounts/AuthSubRevokeToken';

    const AUTHSUB_TOKEN_INFO_URI    = 'https://www.google.com/accounts/AuthSubTokenInfo';

     /**

      * Creates a URI to request a single-use AuthSub token.

      *

      * @param string $next (required) URL identifying the service to be

      *                     accessed.

      *  The resulting token will enable access to the specified service only.

      *  Some services may limit scope further, such as read-only access.

      * @param string $scope (required) URL identifying the service to be

      *                      accessed.  The resulting token will enable

      *                      access to the specified service only.

      *                      Some services may limit scope further, such

      *                      as read-only access.

      * @param int $secure (optional) Boolean flag indicating whether the

      *                    authentication transaction should issue a secure

      *                    token (1) or a non-secure token (0). Secure tokens

      *                    are available to registered applications only.

      * @param int $session (optional) Boolean flag indicating whether

      *                     the one-time-use  token may be exchanged for

      *                     a session token (1) or not (0).

      * @param string $request_uri (optional) URI to which to direct the

      *                            authentication request.

      */

     public static function getAuthSubTokenUri($next, $scope, $secure=0, $session=0,

                                               $request_uri = self::AUTHSUB_REQUEST_URI)

     {

         $querystring = '?next=' . urlencode($next)

             . '&scope=' . urldecode($scope)

             . '&secure=' . urlencode($secure)

             . '&session=' . urlencode($session);

         return $request_uri . $querystring;

     }

    /**

     * Upgrades a single use token to a session token

     *

     * @param string $token The single use token which is to be upgraded

     * @param Zend_Http_Client $client (optional) HTTP client to use to

     *                                 make the request

     * @param string $request_uri (optional) URI to which to direct

     *                            the session token upgrade

     * @return string The upgraded token value

     * @throws Zend_Gdata_App_AuthException

     * @throws Zend_Gdata_App_HttpException

     */

    public static function getAuthSubSessionToken(

            $token, $client = null,

            $request_uri = self::AUTHSUB_SESSION_TOKEN_URI)

    {

        $client = self::getHttpClient($token, $client);

        if ($client instanceof Zend_Gdata_HttpClient) {

            $filterResult = $client->filterHttpRequest('GET', $request_uri);

            $url = $filterResult['url'];

            $headers = $filterResult['headers'];

            $client->setHeaders($headers);

            $client->setUri($url);

        } else {

            $client->setUri($request_uri);

        }

        try {

            $response = $client->request('GET');

        } catch (Zend_Http_Client_Exception $e) {

            require_once 'Zend/Gdata/App/HttpException.php';

            throw new Zend_Gdata_App_HttpException($e->getMessage(), $e);

        }

        // Parse Google's response

        if ($response->isSuccessful()) {

            $goog_resp = array();

            foreach (explode("\n", $response->getBody()) as $l) {

                $l = chop($l);

                if ($l) {

                    list($key, $val) = explode('=', chop($l), 2);

                    $goog_resp[$key] = $val;

                }

            }

            return $goog_resp['Token'];

        } else {

            require_once 'Zend/Gdata/App/AuthException.php';

            throw new Zend_Gdata_App_AuthException(

                    'Token upgrade failed. Reason: ' . $response->getBody());

        }

    }

    /**

     * Revoke a token

     *

     * @param string $token The token to revoke

     * @param Zend_Http_Client $client (optional) HTTP client to use to make the request

     * @param string $request_uri (optional) URI to which to direct the revokation request

     * @return boolean Whether the revokation was successful

     * @throws Zend_Gdata_App_HttpException

     */

    public static function AuthSubRevokeToken($token, $client = null,

                                              $request_uri = self::AUTHSUB_REVOKE_TOKEN_URI)

    {

        $client = self::getHttpClient($token, $client);

        if ($client instanceof Zend_Gdata_HttpClient) {

            $filterResult = $client->filterHttpRequest('GET', $request_uri);

            $url = $filterResult['url'];

            $headers = $filterResult['headers'];

            $client->setHeaders($headers);

            $client->setUri($url);

            $client->resetParameters();

        } else {

            $client->setUri($request_uri);

        }

        ob_start();

        try {

            $response = $client->request('GET');

        } catch (Zend_Http_Client_Exception $e) {

            ob_end_clean();

            require_once 'Zend/Gdata/App/HttpException.php';

            throw new Zend_Gdata_App_HttpException($e->getMessage(), $e);

        }

        ob_end_clean();

        // Parse Google's response

        if ($response->isSuccessful()) {

            return true;

        } else {

            return false;

        }

    }

    /**

     * get token information

     *

     * @param string $token The token to retrieve information about

     * @param Zend_Http_Client $client (optional) HTTP client to use to

     *                                 make the request

     * @param string $request_uri (optional) URI to which to direct

     *                            the information request

     */

    public static function getAuthSubTokenInfo(

            $token, $client = null, $request_uri = self::AUTHSUB_TOKEN_INFO_URI)

    {

        $client = self::getHttpClient($token, $client);

        if ($client instanceof Zend_Gdata_HttpClient) {

            $filterResult = $client->filterHttpRequest('GET', $request_uri);

            $url = $filterResult['url'];

            $headers = $filterResult['headers'];

            $client->setHeaders($headers);

            $client->setUri($url);

        } else {

            $client->setUri($request_uri);

        }

        ob_start();

        try {

            $response = $client->request('GET');

        } catch (Zend_Http_Client_Exception $e) {

            ob_end_clean();

            require_once 'Zend/Gdata/App/HttpException.php';

            throw new Zend_Gdata_App_HttpException($e->getMessage(), $e);

        }

        ob_end_clean();

        return $response->getBody();

    }

    /**

     * Retrieve a HTTP client object with AuthSub credentials attached

     * as the Authorization header

     *

     * @param string $token The token to retrieve information about

     * @param Zend_Gdata_HttpClient $client (optional) HTTP client to use to make the request

     */

    public static function getHttpClient($token, $client = null)

    {

        if ($client == null) {

            $client = new Zend_Gdata_HttpClient();

        }

        if (!$client instanceof Zend_Gdata_HttpClient) {

            require_once 'Zend/Gdata/App/HttpException.php';

            throw new Zend_Gdata_App_HttpException('Client is not an instance of Zend_Gdata_HttpClient.');

        }

        $useragent = 'Zend_Framework_Gdata/' . Zend_Version::VERSION;

        $client->setConfig(array(

                'strictredirects' => true,

                'useragent' => $useragent

            )

        );

        $client->setAuthSubToken($token);

        return $client;

    }

}