<?php error_reporting(E_ALL);
/**
 * This file is part of the Dynamic Networks RSS Framework for PHP
 * 
 * @author Gordon Oheim (hide@address.com)
 * @copyright Copyright 2005, Dynamic Networks
 * @link http://www.dynamicnetworks.de
 * @license http://creativecommons.org/licenses/GPL/2.0/ GNU General Public License
 * @filesource
 * @version 1.0.0
 */

/**
 * A class offering XML-DOM functions for creating an RSS Feed.
 *
 * @package rssFramework
 * @author Gordon Oheim (hide@address.com)
 * @abstract
 */
  class parser {

 	/**
 	 * @var domdocument
 	 * @access private
 	 */ 
 	var $dom;
 	
 	/**
 	 * initializes $parser::$dom with a new domdocument.
 	 * 
 	 * @access public
 	 * @see $dom
 	 */
 	function parser() {
 		$this->dom = domxml_new_doc("1.0");
 	}

	/**
	 * Returns the Document Object Model of the RSS feed created by the parser
	 * 
	 * @return DomDocument
	 * @access public
	 */
	function get_dom() {
		return $this->dom;
	}

	/**
	 * Adds a semantic resolution module element to the feed.
	 * 
	 * The function will add a node referencing the Simple Semantic Resolution
	 * Module created by Danny Ayers. Follow the link below for more details on
	 * that.
	 * 
	 * @link http://purl.org/stuff/ssrsr
	 */
	function add_semanticresolutionmodule(&$dom) {
		$rdf = $dom->create_element("rdf");
		$namespace = "http://purl.org/stuff/ssr";
		$rdf->set_namespace($namespace, "ssr");
		$rdf->set_attribute("transform", "http://w3future.com/weblog/gems/rss2rdf.xsl");
		/* apply the license tag to channel and items */
		$node = $dom->get_elements_by_tagname("channel");
		$dom->insert_before($rdf, $node[0]);
		/* send $dom back to user */
 		return $dom;
	}

 	/**
 	 * Sets a creative commons license to channel and items
 	 * 
 	 * This function adds the a Creative Commons license tag to the RSS feed by
 	 * adding a tag called license with a creativeCommons namespace to the XML
 	 * document. The content for the text is supposed to be an URL pointing to
 	 * the site holding the license agreement.
 	 * 
 	 * The function takes up to three arguments, first is the license URL,
 	 * second is the DomDocument and third is a boolean indicating whether the
 	 * license should be applied to all item of the channel.
 	 * 
 	 * Note: the DomDocument is passed by reference, meaning you do not have to
 	 * use the return value. See the example for different types of implementing
 	 * this function.
 	 * 
 	 * @example /docs/examples/add_creativecommonslicense.php
 	 * @link http://www.creativecommons.org
 	 * @link http://backend.userland.com/creativeCommonsRssModule
 	 * @param url $license
 	 * @param DomDocument $dom
 	 * @param bool $channelOnly
 	 * @return domdocument
 	 * @access public
 	 */
 	function add_creativecommonslicense($license, &$dom, $channelOnly = false) {
		
		/* create a new nodeset containing the license */
		$creativeCommons = $dom->create_element("license");
		$namespace = "http://backend.userland.com/creativeCommonsRssModule";
		$creativeCommons->set_namespace($namespace, "creativeCommons");
		$license = $dom->create_text_node($license->get_url());
		$creativeCommons->append_child($license);
		
		/* apply the license tag to channel and items */
		$node = $dom->get_elements_by_tagname("description");
		$dom->insert_before($creativeCommons, $node[0]->next_sibling());
		if ($channelOnly == false) {
			$items = $dom->get_elements_by_tagname("item");
			for ($i = 0; $i<count($items); $i++) {
   				$items[$i]->append_child($creativeCommons->clone_node(true));
			}
		}
 		/* send $dom back to user */
 		return $dom;
 	}
 	
	/**
	 * Transforms the DomDocument
	 * 
	 * This function applies the specified XSL Transformation to the
	 * DomDocument. The default transformation is from dump to RSS, but you can
	 * specify whatever xslt file you need. If you pass transformer->get_dom()
	 * to the function as the first param, the transformer will overwrite your
	 * dump DomDocument with the DomDocument from the Transformation. If you do
	 * not want that to happen, copy the dump DomDocument into a variable first.
	 *
	 * @param DomDocument $dom
	 * @param file $xslt
	 * @return DomDocument
	 * @access public
	 */
	function transform(&$dom, $xslt = './src/xslt/RSS20/to_rss20.xslt') {
		$xsldoc = domxml_xslt_stylesheet_file($xslt);
		return $dom = $xsldoc->process($dom);
	}
  }
?>