<?php
/**
 * $Id$
 *
 * KnowledgeTree Community Edition
 * Document Management Made Simple
 * Copyright (C) 2008, 2009 KnowledgeTree Inc.
 * 
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 3 as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * You can contact KnowledgeTree Inc., PO Box 7775 #87847, San Francisco,
 * California 94120-7775, or email info@knowledgetree.com.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "Powered by
 * KnowledgeTree" logo and retain the original copyright notice. If the display of the
 * logo is not reasonably feasible for technical reasons, the Appropriate Legal Notices
 * must display the words "Powered by KnowledgeTree" and retain the original
 * copyright notice.
 * Contributor( s): ______________________________________
 *
 */

require_once( KT_LIB_DIR . '/plugins/plugin.inc.php');

class KTPluginRegistry {
    var $_aPluginDetails = array();
    var $_aPlugins = array();

    static function &getSingleton() {
		if (!KTUtil::arrayGet($GLOBALS['_KT_PLUGIN'], 'oKTPluginRegistry')) {
			$GLOBALS['_KT_PLUGIN']['oKTPluginRegistry'] = new KTPluginRegistry;
		}
		return $GLOBALS['_KT_PLUGIN']['oKTPluginRegistry'];
   	}

   	/**
     * Register the plugin in the database
     *
     * @param unknown_type $sClassName
     * @param unknown_type $sNamespace
     * @param unknown_type $sFilename
     */
    function registerPlugin($sClassName, $sNamespace, $sFilename = null) {
        $sFilename = (!empty($sFilename)) ? KTPlugin::_fixFilename($sFilename) : '';
        $this->_aPluginDetails[$sNamespace] = array($sClassName, $sNamespace, $sFilename);

        /*
        Check whether the system is registering or not. If true, register the plugin in plugin_helper.
        If false, skip.
        This check has been put in place to prevent the plugin being registered on every page load.
        */
        if(isset($_SESSION['plugins_registerplugins']) && $_SESSION['plugins_registerplugins']){
            $object = $sClassName.'|'.$sNamespace.'|'.$sFilename;
            KTPlugin::registerPluginHelper($sNamespace, $sClassName, $sFilename, $object, 'general', 'plugin');
        }
    }

    function &getPlugin($sNamespace) {
        if (array_key_exists($sNamespace, $this->_aPlugins)) {
            return $this->_aPlugins[$sNamespace];
        }
        $aDetails = KTUtil::arrayGet($this->_aPluginDetails, $sNamespace);
        if (empty($aDetails)) {
                return null;
        }
        $sFilename = (KTUtil::isAbsolutePath($aDetails[2])) ? $aDetails[2] : KT_DIR.'/'.$aDetails[2];
        if (!empty($sFilename)) {
            require_once($sFilename);
        }
        $sClassName = $aDetails[0];
        $oPlugin = new $sClassName($sFilename);

        $this->_aPlugins[$sNamespace] =& $oPlugin;
        return $oPlugin;
    }

    function &getPlugins() {
        $aRet = array();
        foreach (array_keys($this->_aPluginDetails) as $sPluginName) {
            $oPlugin =& $this->getPlugin($sPluginName);
            $aRet[(int)$oPlugin->iOrder][] =& $oPlugin;
        }
        ksort($aRet);
        $aRes = array();
        foreach($aRet as $iOrder => $aPlugins) {
            foreach(array_keys($aPlugins) as $iPlugin) {
                $aRes[] =& $aRet[$iOrder][$iPlugin];
            }
        }
        return $aRes;
    }
}