<?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.
 */

/**
 * Utility functions useful in managing GalleryUsers
 * @package GalleryCore
 * @subpackage Helpers
 * @author Bharat Mediratta <bharat@menalto.com>
 * @version $Revision: 17580 $
 * @static
 */
class GalleryUserHelper_simple {

    /**
     * @see GalleryCoreApi::assertHasItemPermission
     */
    function assertHasItemPermission($itemId, $permission) {
	global $gallery;

	list ($ret, $hasPermission) =
	    GalleryUserHelper_simple::hasItemPermission($itemId, $permission);
	if ($ret) {
	    return $ret;
	}

	if (!$hasPermission) {
	    return GalleryCoreApi::error(
		ERROR_PERMISSION_DENIED, __FILE__, __LINE__,
		sprintf('user id: %s doesn\'t have permission: %s for item id: %s',
			$gallery->getActiveUserId(), $permission, $itemId));
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::hasItemPermission
     */
    function hasItemPermission($itemId, $permission, $userId=null, $sessionPermissions=true) {
	global $gallery;
	if (!isset($userId)) {
	    $userId = $gallery->getActiveUserId();
	}
	$sessionPermissions = (int)$sessionPermissions;

	$cacheKey = "GalleryPermissionHelper::getPermissions($itemId,$userId,$sessionPermissions)";
	if (GalleryDataCache::containsKey($cacheKey)) {
	    $permissions = GalleryDataCache::get($cacheKey);
	    return array(null, isset($permissions[$permission]));
	}

	/* Only use the permission cache from the session data for the activeUser */
	if ($sessionPermissions && $userId == $gallery->getActiveUserId()
		&& GalleryDataCache::hasPermission($itemId, $permission)) {
	    return array(null, true);
	}

	list ($ret, $aclIds) =
	    GalleryCoreApi::fetchAccessListIds($permission, $userId, $sessionPermissions);
	if ($ret) {
	    return array($ret, null);
	}
	if (empty($aclIds)) {
	    return array(null, false);
	}
	$aclMarkers = GalleryUtilities::makeMarkers(count($aclIds));

	/*
	 * TODO: We could get and cache the accessListId here, and then do a
	 * hash lookup to see if it's in our valid aclid list.
	 */
	list ($ret, $searchResults) = GalleryCoreApi::getMapEntry('GalleryAccessSubscriberMap',
	    array('itemId'), array('itemId' => (int)$itemId, 'accessListId' => $aclIds),
	    array('limit' => array('count' => 1)));
	if ($ret) {
	    return array($ret, null);
	}

	$hasPermission = ($searchResults->resultCount() > 0);

	return array(null, $hasPermission);
    }
}
?>