<?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.
 */

/**
 * Helper functions for ItemAttributes map.
 * @package GalleryCore
 * @subpackage Helpers
 * @author Bharat Mediratta <bharat@menalto.com>
 * @version $Revision: 17580 $
 * @static
 */
class GalleryItemAttributesHelper_simple {

    /**
     * @see GalleryCoreApi::incrementItemViewCount
     */
    function incrementViewCount($itemId, $step=1) {
	global $gallery;
	$session =& $gallery->getSession();

	$elapsed = time() - $session->getCreationTime();
	if (!$session->exists('core.lastViewed')) {
	    if (!$session->isPersistent()) {
		/*
		 * For guests, we don't create a session.  So the lastViewed data is not available
		 * for guests.  Thus, rely on HTTP If-Modified-Since for guests which is admittedly
		 * quite unreliable.  Alternatively we could store this data on the client with a
		 * non-session cookie but sending lastViewed data on each request could take a lot
		 * of bandwidth.
		 */
		$phpVm = $gallery->getPhpVm();
		if (GalleryUtilities::getServerVar('HTTP_IF_MODIFIED_SINCE')
			|| ($phpVm->function_exists('getallheaders')
			    && ($headers = $phpVm->getallheaders())
			    && (isset($headers['If-Modified-Since'])
				|| isset($headers['If-modified-since'])))) {
		    return null;
		}

		/* Known search engines don't affect view counts */
		if ($session->isSearchEngineSession()) {
		    return null;
		}

		if (!$phpVm->headers_sent()) {
		    GalleryUtilities::setResponseHeader('Last-Modified: '
			. GalleryUtilities::getHttpDate($phpVm->time()));
		    GalleryUtilities::setResponseHeader('Expires: '
			. GalleryUtilities::getHttpDate(time() - 3600 * 24 * 7));
		}
	    }

	    $lastViewed = array($itemId => $elapsed);
	    $session->put('core.lastViewed', $lastViewed);
	} else {
	    $lastViewed =& $session->get('core.lastViewed');
	    if (isset($lastViewed[$itemId])) {
		if ($elapsed - $lastViewed[$itemId] < 86400) {
		    /* They viewed it within the last day, so this doesn't count */
		    return null;
		}
	    }
	    $lastViewed[$itemId] = $elapsed;
	}

	/* Ensure GallerySqlFragment class is loaded by initializing storage */
	$gallery->getStorage();
	$func = '= [GalleryItemAttributesMap::viewCount] + ?';
	$ret = GalleryCoreApi::updateMapEntry(
	    'GalleryItemAttributesMap',
	    array('itemId' => $itemId),
	    array('viewCount' => new GallerySqlFragment($func, $step)));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::fetchItemViewCount
     */
    function fetchViewCount($itemId) {
	list ($ret, $viewCounts) =
	    GalleryItemAttributesHelper_simple::fetchViewCounts(array($itemId));
	if ($ret) {
	    return array($ret, null);
	}

	return array(null, $viewCounts[$itemId]);
    }

    /**
     * @see GalleryCoreApi::fetchItemViewCounts
     */
    function fetchViewCounts($itemIds) {
	foreach ($itemIds as $idx => $id) {
	    $itemIds[$idx] = (int)$id;
	}
	list ($ret, $searchResults) = GalleryCoreApi::getMapEntry('GalleryItemAttributesMap',
	    array('itemId', 'viewCount'), array('itemId' => $itemIds));
	if ($ret) {
	    return array($ret, null);
	}

	if ($searchResults->resultCount() != sizeof($itemIds)) {
	    return array(GalleryCoreApi::error(ERROR_MISSING_OBJECT), null);
	}

	$data = array();
	while ($result = $searchResults->nextResult()) {
	    $data[$result[0]] = (int)$result[1];
	}

	return array(null, $data);
    }

    /**
     * @see GalleryCoreApi::fetchParentSequence
     */
    function fetchParentSequence($itemId, $filterBreadcrumb=false) {
	global $gallery;
	if ($filterBreadcrumb && ($filter = $gallery->getConfig('breadcrumbRootId'))
		&& $itemId == $filter) {
	    return array(null, array());
	}

	list ($ret, $searchResults) = GalleryCoreApi::getMapEntry('GalleryItemAttributesMap',
	    array('parentSequence'), array('itemId' => (int)$itemId));
	if ($ret) {
	    return array($ret, null);
	}

	if ($searchResults->resultCount() != 1) {
	    return array(GalleryCoreApi::error(ERROR_MISSING_OBJECT, __FILE__, __LINE__,
					      "ParentSequence for $itemId"), null);
	}

	$result = $searchResults->nextResult();
	/* DB2 doesn't trim when storing data in a varchar column */
	$parentSequence = preg_split('/\//', trim($result[0]), -1, PREG_SPLIT_NO_EMPTY);
	$result = is_array($parentSequence) ? $parentSequence : array();

	if ($filterBreadcrumb && $filter && ($i = array_search($filter, $result))) {
	    array_splice($result, 0, $i);
	}

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