<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Updater
 *
 * @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;

jimport('joomla.filesystem.file');
jimport('joomla.filesystem.folder');
jimport('joomla.filesystem.archive');
jimport('joomla.filesystem.path');
jimport('joomla.base.adapter');

/**
 * Updater Class
 * @package     Joomla.Platform
 * @subpackage  Update
 * @since 11.1
 */
class JUpdater extends JAdapter {

    /**
     * Constructor
     */
    public function __construct() {
        // Adapter base path, class prefix
        parent::__construct(dirname(__FILE__),'JUpdater');
    }

    /**
     * Returns a reference to the global Installer object, only creating it
     * if it doesn't already exist.
     *
     * @return  object  An installer object
     * 
     */
    public static function &getInstance()
    {
        static $instance;

        if (!isset ($instance)) {
            $instance = new JUpdater;
        }
        return $instance;
    }

    /**
     * Finds an update for an extension
     * 
     * @param int Extension Identifier; if zero use all sites
     * 
     * @return boolean If there are updates or not
     */
    public function findUpdates($eid=0) {
        $dbo = $this->getDBO();
        $retval = false;
        // Push it into an array
        if(!is_array($eid)) {
            $query = 'SELECT DISTINCT update_site_id, type, location FROM #__update_sites WHERE enabled = 1';
        } else {
            $query = 'SELECT DISTINCT update_site_id, type, location FROM #__update_sites WHERE update_site_id IN (SELECT update_site_id FROM #__update_sites_extensions WHERE extension_id IN ('. implode(',', $eid) .'))';
        }
        $dbo->setQuery($query);
        $results = $dbo->loadAssocList();
        $result_count = count($results);
        for($i = 0; $i < $result_count; $i++)
        {
            $result = &$results[$i];
            $this->setAdapter($result['type']);
            if(!isset($this->_adapters[$result['type']])) {
                // Ignore update sites requiring adapters we don't have installed
                continue; 
            }
            $update_result = $this->_adapters[$result['type']]->findUpdate($result);
            if(is_array($update_result))
            {
                if(array_key_exists('update_sites',$update_result) && count($update_result['update_sites']))
                {
                    $results = $this->arrayUnique(array_merge($results, $update_result['update_sites']));
                    $result_count = count($results);
                }
                if(array_key_exists('updates', $update_result) && count($update_result['updates']))
                {
                    for($k = 0; $k < count($update_result['updates']); $k++)
                    {
                        $current_update = &$update_result['updates'][$k];
                        $update = JTable::getInstance('update');
                        $extension = JTable::getInstance('extension');
                        $uid = $update->find(Array('element'=>strtolower($current_update->get('element')),
                                'type'=>strtolower($current_update->get('type')),
                                'client_id'=>strtolower($current_update->get('client_id')),
                                'folder'=>strtolower($current_update->get('folder'))));

                        $eid = $extension->find(Array('element'=>strtolower($current_update->get('element')),
                                'type'=>strtolower($current_update->get('type')),
                                'client_id'=>strtolower($current_update->get('client_id')),
                                'folder'=>strtolower($current_update->get('folder'))));
                        if(!$uid)
                        {
                            // Set the extension id
                            if($eid)
                            {
                                // We have an installed extension, check the update is actually newer
                                $extension->load($eid);
                                $data = json_decode($extension->manifest_cache, true);
                                if(version_compare($current_update->version, $data['version'], '>') == 1)
                                {
                                    $current_update->extension_id = $eid;
                                    $current_update->store();
                                }
                            } else
                            {
                                // A potentially new extension to be installed
                                $current_update->store();
                            }
                        } else
                        {
                            $update->load($uid);
                            // if there is an update, check that the version is newer then replaces
                            if(version_compare($current_update->version, $update->version, '>') == 1)
                            {
                                $current_update->store();
                            }
                        }
                    }
                }
                $update_result = true;
            } else if ($retval) {
                $update_result = true;
            }
        }
        return $retval;
    }

    /**
     * Multidimensional array safe unique test
     * Borrowed from PHP.net
     * @see http://au2.php.net/manual/en/function.array-unique.php
     */
    public function arrayUnique($myArray)
    {
        if (!is_array($myArray)) {
            return $myArray;
        }

        foreach ($myArray as &$myvalue){
            $myvalue=serialize($myvalue);
        }

        $myArray=array_unique($myArray);

        foreach ($myArray as &$myvalue){
            $myvalue=unserialize($myvalue);
        }

        return $myArray;
    }

    public function update($id)
    {
        $updaterow = JTable::getInstance('update');
        $updaterow->load($id);
        $update = new JUpdate();
        if($update->loadFromXML($updaterow->detailsurl)) {
            return $update->install();
        }
        return false;
    }
}