<?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_advanced {

    /**
     * @see GalleryCoreApi::rebalanceChildOrderWeights
     */
    function rebalanceChildOrderWeights($parentItemId, $spacing=1000) {
	global $gallery;

	list ($ret, $parentItem) = GalleryCoreApi::loadEntitiesById($parentItemId, 'GalleryItem');
	if ($ret) {
	    return $ret;
	}

	list ($ret, $ids) = GalleryCoreApi::fetchChildItemIdsIgnorePermissions($parentItem);
	if ($ret) {
	    return $ret;
	}

	$current = $spacing;
	foreach ($ids as $id) {
	    $gallery->guaranteeTimeLimit(5);
	    $ret = GalleryItemAttributesHelper_advanced::setOrderWeight($id, $current);
	    if ($ret) {
		return $ret;
	    }
	    $current += $spacing;
	}

	return null;
    }

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

	$aggregate = ($direction == LOWER_WEIGHT) ? 'MIN' : 'MAX';

	$query = '
	SELECT
	  ' . $aggregate . '([GalleryItemAttributesMap::orderWeight])
	FROM
	  [GalleryItemAttributesMap], [GalleryChildEntity]
	WHERE
	  [GalleryChildEntity::id] = [GalleryItemAttributesMap::itemId]
	  AND
	  [GalleryChildEntity::parentId] = ?
	';
	list ($ret, $searchResults) = $gallery->search($query, array((int)$itemId));
	if ($ret) {
	    return array($ret, null);
	}

	$result = $searchResults->nextResult();
	$weight = isset($result[0]) ? (int)$result[0] : 0;

	return array(null, $weight);
    }

    /**
     * @see GalleryCoreApi::fetchNextItemWeight
     */
    function fetchNextWeight($itemId, $direction) {
	global $gallery;

	if ($direction == LOWER_WEIGHT) {
	    $aggregate = 'MAX';
	    $comparison = '<';
	} else {
	    $aggregate = 'MIN';
	    $comparison = '>';
	}

	$query = '
	SELECT
	  ' . $aggregate . '([GalleryItemAttributesMap=2::orderWeight])
	FROM
	  [GalleryItemAttributesMap=1], [GalleryItemAttributesMap=2],
	  [GalleryChildEntity=1], [GalleryChildEntity=2]
	WHERE
	  [GalleryChildEntity=1::id] = ?
	  AND
	  [GalleryChildEntity=1::parentId] = [GalleryChildEntity=2::parentId]
	  AND
	  [GalleryChildEntity=1::id] = [GalleryItemAttributesMap=1::itemId]
	  AND
	  [GalleryChildEntity=2::id] = [GalleryItemAttributesMap=2::itemId]
	  AND
	  [GalleryItemAttributesMap=2::orderWeight] ' .
		$comparison . ' [GalleryItemAttributesMap=1::orderWeight]
	';
	list ($ret, $searchResults) = $gallery->search($query, array((int)$itemId));
	if ($ret) {
	    return array($ret, null);
	}

	$result = $searchResults->nextResult();
	$weight = isset($result[0]) ? (int)$result[0] : null;

	return array(null, $weight);
    }

    /**
     * @see GalleryCoreApi::setItemViewCount
     */
    function setViewCount($itemId, $count) {
	$ret = GalleryCoreApi::updateMapEntry(
	    'GalleryItemAttributesMap',
	    array('itemId' => $itemId),
	    array('viewCount' => $count));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::setParentSequence
     */
    function setParentSequence($itemId, $parentSequence) {
	if (empty($parentSequence)) {
	    $parentSequence = '';
	} else {
	    $parentSequence = join('/', $parentSequence) . '/';
	}

	$ret = GalleryCoreApi::updateMapEntry(
	    'GalleryItemAttributesMap',
	    array('itemId' => $itemId),
	    array('parentSequence' => $parentSequence));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::createItemAttributes
     */
    function createItemAttributes($itemId, $parentSequence) {
	if (empty($parentSequence)) {
	    $parentSequence = '';
	} else {
	    $parentSequence = join('/', $parentSequence) . '/';
	}
	$ret = GalleryCoreApi::addMapEntry(
	    'GalleryItemAttributesMap',
	    array('itemId' => $itemId,
		  'viewCount' => 0,
		  'orderWeight' => 0,
		  'parentSequence' => $parentSequence));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::removeItemAttributes
     */
    function removeItemAttributes($itemId) {
	$ret = GalleryCoreApi::removeMapEntry(
	    'GalleryItemAttributesMap', array('itemId' => $itemId));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::setItemOrderWeight
     */
    function setOrderWeight($itemId, $orderWeight) {
	$ret = GalleryCoreApi::updateMapEntry(
	    'GalleryItemAttributesMap',
	    array('itemId' => $itemId),
	    array('orderWeight' => $orderWeight));
	if ($ret) {
	    return $ret;
	}

	return null;
    }

    /**
     * @see GalleryCoreApi::updateParentSequence
     */
    function updateParentSequence($oldParentSequence, $newParentSequence) {
	global $gallery;

	$oldParentSequence = join('/', $oldParentSequence) . '/';
	$newParentSequence = join('/', $newParentSequence) . '/';

	$storage =& $gallery->getStorage();
	list ($ret, $substring) = $storage->getFunctionSql('SUBSTRING', array(
		  '[GalleryItemAttributesMap::parentSequence]', strlen($oldParentSequence) + 1));
	if ($ret) {
	    return $ret;
	}
	list ($ret, $newSequenceSql) = $storage->getFunctionSql('CONCAT', array('?', $substring));
	if ($ret) {
	    return $ret;
	}

	$ret = GalleryCoreApi::updateMapEntry(
	    'GalleryItemAttributesMap',
	    array('parentSequence' =>
		  new GallerySqlFragment('LIKE ?', $oldParentSequence . '%')),
	    array('parentSequence' =>
		  new GallerySqlFragment('=' . $newSequenceSql, $newParentSequence)));
	if ($ret) {
	    return $ret;
	}

	return null;
    }
}
?>