<?php
// $Id: online.php,v 1.2.16.1 2006/02/06 08:31:10 onokazu Exp $
//  ------------------------------------------------------------------------ //
//                XOOPS - PHP Content Management System                      //
//                    Copyright (c) 2000 XOOPS.org                           //
//                       <http://www.xoops.org/>                             //
//  ------------------------------------------------------------------------ //
//  This program is free software; you can redistribute it and/or modify     //
//  it under the terms of the GNU General Public License as published by     //
//  the Free Software Foundation; either version 2 of the License, or        //
//  (at your option) any later version.                                      //
//                                                                           //
//  You may not change or alter any portion of this comment or credits       //
//  of supporting developers from this source code or any supporting         //
//  source code which is considered copyrighted (c) material of the          //
//  original comment or credit authors.                                      //
//                                                                           //
//  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, write to the Free Software              //
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA //
//  ------------------------------------------------------------------------ //
// Author: Kazumi Ono (AKA onokazu)                                          //
// URL: http://www.myweb.ne.jp/, http://www.xoops.org/, http://jp.xoops.org/ //
// Project: The XOOPS Project                                                //
// ------------------------------------------------------------------------- //
/**
 * @package     kernel
 * 
 * @author      Kazumi Ono  <onokazu@xoops.org>
 * @copyright   copyright (c) 2000-2003 XOOPS.org
 */

/**
 * A handler for "Who is Online?" information
 * 
 * @package     kernel
 * 
 * @author      Kazumi Ono  <onokazu@xoops.org>
 * @copyright   copyright (c) 2000-2003 XOOPS.org
 */
class XoopsOnlineHandler
{

    /**
     * Database connection
     * 
     * @var object
     * @access  private
     */
    var $db;

    /**
     * Constructor
     * 
     * @param   object  &$db    {@link XoopsHandlerFactory} 
     */
    function XoopsOnlineHandler(&$db)
    {
        $this->db =& $db;
    }

    /**
     * Write online information to the database
     * 
     * @param   int     $uid    UID of the active user
     * @param   string  $uname  Username
     * @param   string  $timestamp
     * @param   string  $module Current module
     * @param   string  $ip     User's IP adress
     * 
     * @return  bool    TRUE on success
     */
    function write($uid, $uname, $time, $module, $ip)
    {
        $uid = intval($uid);
        if ($uid > 0) {
            $sql = "SELECT COUNT(*) FROM ".$this->db->prefix('online')." WHERE online_uid=".$uid;
        } else {
            $sql = "SELECT COUNT(*) FROM ".$this->db->prefix('online')." WHERE online_uid=".$uid." AND online_ip='".$ip."'";
        }
        list($count) = $this->db->fetchRow($this->db->queryF($sql));
        if ( $count > 0 ) {
            $sql = "UPDATE ".$this->db->prefix('online')." SET online_updated=".$time.", online_module = ".$module." WHERE online_uid = ".$uid;
            if ($uid == 0) {
                $sql .= " AND online_ip='".$ip."'";
            }
        } else {
            $sql = sprintf("INSERT INTO %s (online_uid, online_uname, online_updated, online_ip, online_module) VALUES (%u, %s, %u, %s, %u)", $this->db->prefix('online'), $uid, $this->db->quoteString($uname), $time, $this->db->quoteString($ip), $module);
        }
        if (!$this->db->queryF($sql)) {
            return false;
        }
        return true;
    }

    /**
     * Delete online information for a user
     * 
     * @param   int $uid    UID
     * 
     * @return  bool    TRUE on success
     */
    function destroy($uid)
    {
        $sql = sprintf("DELETE FROM %s WHERE online_uid = %u", $this->db->prefix('online'), $uid);
        if (!$result = $this->db->queryF($sql)) {
            return false;
        }
        return true;
    }

    /**
     * Garbage Collection
     * 
     * Delete all online information that has not been updated for a certain time
     * 
     * @param   int $expire Expiration time in seconds
     */
    function gc($expire)
    {
        $sql = sprintf("DELETE FROM %s WHERE online_updated < %u", $this->db->prefix('online'), time() - intval($expire));
        $this->db->queryF($sql);
    }

    /**
     * Get an array of online information
     * 
     * @param   object  $criteria   {@link CriteriaElement} 
     * @return  array   Array of associative arrays of online information
     */
    function &getAll($criteria = null)
    {
        $ret = array();
        $limit = $start = 0;
        $sql = 'SELECT * FROM '.$this->db->prefix('online');
        if (is_object($criteria) && is_subclass_of($criteria, 'criteriaelement')) {
            $sql .= ' '.$criteria->renderWhere();
            $limit = $criteria->getLimit();
            $start = $criteria->getStart();
        }
        if ($result = $this->db->query($sql, $limit, $start)) {
            while ($myrow = $this->db->fetchArray($result)) {
                $ret[] =& $myrow;
                unset($myrow);
            }
        }
        return $ret;
    }

    /**
     * Count the number of online users
     * 
     * @param   object  $criteria   {@link CriteriaElement} 
     */
    function getCount($criteria = null)
    {
        $sql = 'SELECT COUNT(*) FROM '.$this->db->prefix('online');
        if (is_object($criteria) && is_subclass_of($criteria, 'criteriaelement')) {
            $sql .= ' '.$criteria->renderWhere();
        }
        $ret = false;
        if ($result = $this->db->query($sql)) {
            list($ret) = $this->db->fetchRow($result);
        }
        return $ret;
    }
}
?>