<?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_Feed

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

 */

/**

 * @see Zend_Feed_Entry_Abstract

 */

require_once 'Zend/Feed/Entry/Abstract.php';

/**

 * Concrete class for working with Atom entries.

 *

 * @category   Zend

 * @package    Zend_Feed

 * @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_Feed_Entry_Atom extends Zend_Feed_Entry_Abstract

{

    /**

     * Content-Type

     */

    const CONTENT_TYPE = 'application/atom+xml';

    /**

     * Root XML element for Atom entries.

     *

     * @var string

     */

    protected $_rootElement = 'entry';

    /**

     * Root namespace for Atom entries.

     *

     * @var string

     */

    protected $_rootNamespace = 'atom';

    /**

     * Delete an atom entry.

     *

     * Delete tries to delete this entry from its feed. If the entry

     * does not contain a link rel="edit", we throw an error (either

     * the entry does not yet exist or this is not an editable

     * feed). If we have a link rel="edit", we do the empty-body

     * HTTP DELETE to that URI and check for a response of 2xx.

     * Usually the response would be 204 No Content, but the Atom

     * Publishing Protocol permits it to be 200 OK.

     *

     * @return void

     * @throws Zend_Feed_Exception

     */

    public function delete()

    {

        // Look for link rel="edit" in the entry object.

        $deleteUri = $this->link('edit');

        if (!$deleteUri) {

            /**

             * @see Zend_Feed_Exception

             */

            require_once 'Zend/Feed/Exception.php';

            throw new Zend_Feed_Exception('Cannot delete entry; no link rel="edit" is present.');

        }

        // DELETE

        $client = Zend_Feed::getHttpClient();

        do {

            $client->setUri($deleteUri);

            if (Zend_Feed::getHttpMethodOverride()) {

                $client->setHeader('X-HTTP-Method-Override', 'DELETE');

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

            } else {

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

            }

            $httpStatus = $response->getStatus();

            switch ((int) $httpStatus / 100) {

                // Success

                case 2:

                    return true;

                // Redirect

                case 3:

                    $deleteUri = $response->getHeader('Location');

                    continue;

                // Error

                default:

                    /**

                     * @see Zend_Feed_Exception

                     */

                    require_once 'Zend/Feed/Exception.php';

                    throw new Zend_Feed_Exception("Expected response code 2xx, got $httpStatus");

            }

        } while (true);

    }

    /**

     * Save a new or updated Atom entry.

     *

     * Save is used to either create new entries or to save changes to

     * existing ones. If we have a link rel="edit", we are changing

     * an existing entry. In this case we re-serialize the entry and

     * PUT it to the edit URI, checking for a 200 OK result.

     *

     * For posting new entries, you must specify the $postUri

     * parameter to save() to tell the object where to post itself.

     * We use $postUri and POST the serialized entry there, checking

     * for a 201 Created response. If the insert is successful, we

     * then parse the response from the POST to get any values that

     * the server has generated: an id, an updated time, and its new

     * link rel="edit".

     *

     * @param  string $postUri Location to POST for creating new entries.

     * @return void

     * @throws Zend_Feed_Exception

     */

    public function save($postUri = null)

    {

        if ($this->id()) {

            // If id is set, look for link rel="edit" in the

            // entry object and PUT.

            $editUri = $this->link('edit');

            if (!$editUri) {

                /**

                 * @see Zend_Feed_Exception

                 */

                require_once 'Zend/Feed/Exception.php';

                throw new Zend_Feed_Exception('Cannot edit entry; no link rel="edit" is present.');

            }

            $client = Zend_Feed::getHttpClient();

            $client->setUri($editUri);

            if (Zend_Feed::getHttpMethodOverride()) {

                $client->setHeaders(array('X-HTTP-Method-Override: PUT',

                    'Content-Type: ' . self::CONTENT_TYPE));

                $client->setRawData($this->saveXML());

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

            } else {

                $client->setHeaders('Content-Type', self::CONTENT_TYPE);

                $client->setRawData($this->saveXML());

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

            }

            if ($response->getStatus() !== 200) {

                /**

                 * @see Zend_Feed_Exception

                 */

                require_once 'Zend/Feed/Exception.php';

                throw new Zend_Feed_Exception('Expected response code 200, got ' . $response->getStatus());

            }

        } else {

            if ($postUri === null) {

                /**

                 * @see Zend_Feed_Exception

                 */

                require_once 'Zend/Feed/Exception.php';

                throw new Zend_Feed_Exception('PostURI must be specified to save new entries.');

            }

            $client = Zend_Feed::getHttpClient();

            $client->setUri($postUri);

            $client->setHeaders('Content-Type', self::CONTENT_TYPE);

            $client->setRawData($this->saveXML());

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

            if ($response->getStatus() !== 201) {

                /**

                 * @see Zend_Feed_Exception

                 */

                require_once 'Zend/Feed/Exception.php';

                throw new Zend_Feed_Exception('Expected response code 201, got '

                                              . $response->getStatus());

            }

        }

        // Update internal properties using $client->responseBody;

        @ini_set('track_errors', 1);

        $newEntry = new DOMDocument;

        $status = @$newEntry->loadXML($response->getBody());

        @ini_restore('track_errors');

        if (!$status) {

            // prevent the class to generate an undefined variable notice (ZF-2590)

            if (!isset($php_errormsg)) {

                if (function_exists('xdebug_is_enabled')) {

                    $php_errormsg = '(error message not available, when XDebug is running)';

                } else {

                    $php_errormsg = '(error message not available)';

                }

            }

            /**

             * @see Zend_Feed_Exception

             */

            require_once 'Zend/Feed/Exception.php';

            throw new Zend_Feed_Exception('XML cannot be parsed: ' . $php_errormsg);

        }

        $newEntry = $newEntry->getElementsByTagName($this->_rootElement)->item(0);

        if (!$newEntry) {

            /**

             * @see Zend_Feed_Exception

             */

            require_once 'Zend/Feed/Exception.php';

            throw new Zend_Feed_Exception('No root <feed> element found in server response:'

                                          . "\n\n" . $client->responseBody);

        }

        if ($this->_element->parentNode) {

            $oldElement = $this->_element;

            $this->_element = $oldElement->ownerDocument->importNode($newEntry, true);

            $oldElement->parentNode->replaceChild($this->_element, $oldElement);

        } else {

            $this->_element = $newEntry;

        }

    }

    /**

     * Easy access to <link> tags keyed by "rel" attributes.

     *

     * If $elt->link() is called with no arguments, we will attempt to

     * return the value of the <link> tag(s) like all other

     * method-syntax attribute access. If an argument is passed to

     * link(), however, then we will return the "href" value of the

     * first <link> tag that has a "rel" attribute matching $rel:

     *

     * $elt->link(): returns the value of the link tag.

     * $elt->link('self'): returns the href from the first <link rel="self"> in the entry.

     *

     * @param  string $rel The "rel" attribute to look for.

     * @return mixed

     */

    public function link($rel = null)

    {

        if ($rel === null) {

            return parent::__call('link', null);

        }

        // index link tags by their "rel" attribute.

        $links = parent::__get('link');

        if (!is_array($links)) {

            if ($links instanceof Zend_Feed_Element) {

                $links = array($links);

            } else {

                return $links;

            }

        }

        foreach ($links as $link) {

            if (empty($link['rel'])) {

                $link['rel'] = 'alternate'; // see Atom 1.0 spec

            }

            if ($rel == $link['rel']) {

                return $link['href'];

            }

        }

        return null;

    }

}