root/twitter.retweet/files/lib/system/event/listener/TwitterRetweetListener.class.php @ 1337

<?php
require_once(WCF_DIR.'lib/util/TwitterUtil.class.php');

/**
 * 
 * 
 * @author      Torben Brodt
 * @url         http://trac.easy-coding.de/trac/wcf/wiki/twitter
 * @license     GNU General Public License <http://opensource.org/licenses/gpl-3.0.html>
 */
class TwitterRetweetListener implements EventListener {

        /**
         * @see EventListener::execute()
         */
        public function execute($eventObj, $className, $eventName) {
        
                //TODO: display retweets
        
                foreach($eventObj->links as $link) {
                
        
                        $link = $this->rdfAutoDiscover($link);
                
                        if($this->isHomeLink($link)) {
                                $query = parse_url($link, PHP_URL_QUERY);
                                parse_str($query, $output);
                                
                                $this->link($eventObj, $output['action'], $output['objectID'], $output['objectType'], $output['packageID']);
                        }
                }
        }

        /**
         *
         */
        protected function isHomeLink($link) {
                if(empty($link)) {
                        return false;
                }

                // TODO: does this link point to PAGE_URL ?

                return true;
        }

        protected function link() {
                // TODO: insert wcf1_twitter_message_retweet
        }
        
        /**
         * @return string
         */
        protected function rdfAutoDiscover($trackbackURL) {
                // fetch page content
                $pageContent = @file_get_contents($trackbackURL);
                $didDiscover = false;
                
                if ($pageContent !== false) {
                        // search for RDF instructions
                        if (preg_match_all('/(<rdf:RDF.*?<\/rdf:RDF>)/sm', $pageContent, $matches)) {
                                foreach($matches[0] as $rdfInstructions) {
                                        if (preg_match('|dc\:identifier\=\"'.preg_quote($trackbackURL).'\"|isU', $rdfInstructions)) {
                                                // get pingback URL
                                                if (preg_match('/trackback\:ping\=\"([^"]+)\"/isU', $rdfInstructions, $pingbackURL)) {
                                                        
                                                        return $pingbackURL[1];
                                                }
                                        }
                                }
                        }
                }
                return '';
        }
}
?>