<?php
/*
 * Gallery - a web based photo album viewer and editor
 * Copyright (C) 2000-2008 Bharat Mediratta
 *
 * 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.
 *
 * 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., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
 */

GalleryCoreApi::requireOnce('modules/core/AdminMaintenance.inc');

/**
 * This is a MaintenanceTask that removes all expired sessions from the database.
 * @package GalleryCore
 * @subpackage Classes
 * @author Andy Staudacher <ast@gmx.ch>
 * @version $Revision: 17580 $
 */
class DeleteSessionsTask extends MaintenanceTask {
    /**
     * @see MaintenanceTask::getInfo
     */
    function getInfo() {
	global $gallery;

	return array('l10Domain' => 'modules_core',
		     'title' => $gallery->i18n('Delete user sessions'),
		     'description' => $gallery->i18n(
			 'Delete all persistent user sessions according to your current session ' .
			 'expiration settings.'));
    }

    /**
     * @see MaintenanceTask::run
     */
    function run() {
	global $gallery;
	$templateAdapter =& $gallery->getTemplateAdapter();
	$session =& $gallery->getSession();
	$phpVm = $gallery->getPhpVm();

	list ($ret, $module) = GalleryCoreApi::loadPlugin('module', 'core');
	if ($ret) {
	    return array($ret, null, null);
	}

	/* Touch this admin session to ensure that we don't delete it */
	$session->put('touch', $phpVm->time());
	$ret = $session->save();
	if ($ret) {
	    return array($ret, null, null);
	}

	list ($ret, $params) = GalleryCoreApi::fetchAllPluginParameters('module', 'core');
	if ($ret) {
	    return array($ret, null, null);
	}
	$inactivityTimeout = (int)$params['session.inactivityTimeout'];
	$lifetime = (int)$params['session.lifetime'];
	list ($ret, $anonymousUserId) = GalleryCoreApi::getAnonymousUserId();
	if ($ret) {
	    return array($ret, null, null);
	}

	$templateAdapter->updateProgressBar($module->translate('Delete user sessions'), '', 0);

	$data = array($phpVm->time() - $inactivityTimeout, $phpVm->time() - $lifetime,
		      $anonymousUserId, $phpVm->time() - (7 * 86400));

	$query = '
	SELECT COUNT([GallerySessionMap::id])
	FROM [GallerySessionMap]
	WHERE [GallerySessionMap::modificationTimestamp] < ? OR
	      [GallerySessionMap::creationTimestamp] < ? OR
	      ([GallerySessionMap::userId] = ? AND [GallerySessionMap::creationTimestamp] < ?)
	';
	list ($ret, $results) = $gallery->search($query, $data);
	if ($ret) {
	    return array($ret, null, null);
	}
	$result = $results->nextResult();
	$total = $result[0];

	if ($total) {
	    /* This limit controls the query text length, 1000 sessionIds => query size = 32kbyte */
	    $stepSize = $session->_expirationLimit = 1000;
	    $iterations = ceil($total / $stepSize);
	    $option['limit']['count'] = $stepSize;

	    for ($i = 1; $i <= $iterations; $i++) {
		$gallery->guaranteeTimeLimit(120);
		$ret = $session->_expireSessions();
		if ($ret) {
		    return array($ret, null, null);
		}

		$templateAdapter->updateProgressBar(
		    $module->translate('Delete user sessions'), '', $i / $iterations);
	    }
	}

	$templateAdapter->updateProgressBar($module->translate('Delete user sessions'), '', 1);

	$result = array($module->translate(array('text' => 'Deleted %d sessions.',
						 'arg1' => (int)$total)));

	return array(null, true, $result);
    }

    /**
     * @see MaintenanceTask::requiresProgressBar
     */
    function requiresProgressBar() {
	return true;
    }
}
?>