joomla-platform / libraries / joomla / plugin / helper.php

<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Plugin
 *
 * @copyright   Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * Plugin helper class
 *
 * @package     Joomla.Platform
 * @subpackage  Plugin
 * @since       11.1
 */
abstract class JPluginHelper
{
    /**
     * Get the plugin data of a specific type if no specific plugin is specified
     * otherwise only the specific plugin data is returned.
     *
     * @param   string  $type   The plugin type, relates to the sub-directory in the plugins directory.
     * @param   string  $plugin The plugin name.
     *
     * @return  mixed   An array of plugin data objects, or a plugin data object.
     * @since   11.1
     */
    public static function getPlugin($type, $plugin = null)
    {
        $result     = array();
        $plugins    = self::_load();

        // Find the correct plugin(s) to return.
        if (!$plugin) {
            foreach($plugins as $p) {
                // Is this the right plugin?
                if ($p->type == $type) {
                    $result[] = $p;
                }
            }
        } else {
            foreach($plugins as $p) {
                // Is this plugin in the right group?
                if ($p->type == $type && $p->name == $plugin) {
                    $result = $p;
                    break;
                }
            }
        }

        return $result;
    }

    /**
     * Checks if a plugin is enabled.
     *
     * @param   string  $type   The plugin type, relates to the sub-directory in the plugins directory.
     * @param   string  $plugin The plugin name.
     *
     * @return  boolean
     * @since   11.1
     */
    public static function isEnabled($type, $plugin = null)
    {
        $result = self::getPlugin($type, $plugin);
        return (!empty($result));
    }

    /**
     * Loads all the plugin files for a particular type if no specific plugin is specified
     * otherwise only the specific pugin is loaded.
     *
     * @param   string      $type   The plugin type, relates to the sub-directory in the plugins directory.
     * @param   string      $plugin The plugin name.
     * @param   boolean     $autocreate
     * @param   JDispatcher $dispatcher Optionally allows the plugin to use a different dispatcher.
     *
     * @return  boolean     True on success.
     * @since   11.1
     */
    public static function importPlugin($type, $plugin = null, $autocreate = true, $dispatcher = null)
    {
        static $loaded = Array();

        // check for the default args, if so we can optimise cheaply
        $defaults = false;
        if (is_null($plugin) && $autocreate == true && is_null($dispatcher)) {
            $defaults = true;
        }

        if (!isset($loaded[$type]) || !$defaults) {
            $results = null;

            // Load the plugins from the database.
            $plugins = self::_load();

            // Get the specified plugin(s).
            for ($i = 0, $t = count($plugins); $i < $t; $i++) {
                if ($plugins[$i]->type == $type && ($plugins[$i]->name == $plugin ||  $plugin === null)) {
                    self::_import($plugins[$i], $autocreate, $dispatcher);
                    $results = true;
                }
            }

            // Bail out early if we're not using default args
            if(!$defaults) {
                return $results;
            }
            $loaded[$type] = $results;
        }

        return $loaded[$type];
    }

    /**
     * Loads the plugin file.
     *
     * @param   JPlugin     $plugin     The plugin.
     * @param   boolean     $autocreate
     * @param   JDispatcher $dispatcher Optionally allows the plugin to use a different dispatcher.
     *
     * @return  boolean     True on success.
     * @since   11.1
     */
    protected static function _import(&$plugin, $autocreate = true, $dispatcher = null)
    {
        static $paths = array();

        $plugin->type = preg_replace('/[^A-Z0-9_\.-]/i', '', $plugin->type);
        $plugin->name = preg_replace('/[^A-Z0-9_\.-]/i', '', $plugin->name);

        $legacypath = JPATH_PLUGINS.DS.$plugin->type.DS.$plugin->name.'.php';
        $path = JPATH_PLUGINS.DS.$plugin->type.DS.$plugin->name.DS.$plugin->name.'.php';

        if (!isset( $paths[$path] ) || !isset($paths[$legacypath])) {
            $pathExists = file_exists($path);
            if ($pathExists || file_exists($legacypath)) {
                $path = $pathExists ? $path : $legacypath;

                jimport('joomla.plugin.plugin');
                if (!isset($paths[$path])) {
                    require_once $path;
                }
                $paths[$path] = true;

                if ($autocreate) {
                    // Makes sure we have an event dispatcher
                    if (!is_object($dispatcher)) {
                        $dispatcher = JDispatcher::getInstance();
                    }

                    $className = 'plg'.$plugin->type.$plugin->name;
                    if (class_exists($className)) {
                        // Load the plugin from the database.
                        $plugin = self::getPlugin($plugin->type, $plugin->name);

                        // Instantiate and register the plugin.
                        new $className($dispatcher, (array)($plugin));
                    }
                }
            } else {
                $paths[$path] = false;
            }
        }
    }

    /**
     * Loads the published plugins.
     *
     * @return  void
     * @since   11.1
     */
    protected static function _load()
    {
        static $plugins;

        if (isset($plugins)) {
            return $plugins;
        }

        $user   = JFactory::getUser();
        $cache  = JFactory::getCache('com_plugins', '');

        $levels = implode(',', $user->getAuthorisedViewLevels());

        if (!$plugins = $cache->get($levels)) {
            $db     = JFactory::getDbo();
            $query  = $db->getQuery(true);

            $query->select('folder AS type, element AS name, params')
                ->from('#__extensions')
                ->where('enabled >= 1')
                ->where('type ='.$db->Quote('plugin'))
                ->where('state >= 0')
                ->where('access IN ('.$levels.')')
                ->order('ordering');

            $plugins = $db->setQuery($query)
                ->loadObjectList();

            if ($error = $db->getErrorMsg()) {
                JError::raiseWarning(500, $error);
                return false;
            }

            $cache->store($plugins, $levels);
        }

        return $plugins;
    }
}