<?php
/*
 * $RCSfile: GalleryFactoryHelper_simple.class,v $
 *
 * Gallery - a web based photo album viewer and editor
 * Copyright (C) 2000-2005 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.
 */
/**
 * @version $Revision: 1.16 $ $Date: 2005/08/23 03:49:04 $
 * @package GalleryCore
 * @author Bharat Mediratta <bharat@menalto.com>
 */

/**
 * A factory for creating all different kinds of objects
 *
 * @package GalleryCore
 * @subpackage Helpers
 * @abstract
 */
class GalleryFactoryHelper_simple {

    /**
     * Reset the static factory registry
     *
     * @static
     */
    function deleteCache() {
	$cacheParams = array('type' => 'module',
			     'itemId' => 'GalleryFactoryHelper_loadRegistry',
			     'id' => '_all');
	GalleryDataCache::removeFromDisk($cacheParams);

	$registry =& GalleryFactoryHelper_simple::_getSingleton();
	$registry = array();
    }

    /**
     * The single copy of the factory registry data
     *
     * @return object GalleryStatus a status code
     * @access private
     */
    function &_getSingleton() {
	static $registry;
	if (!isset($registry)) {
	    $registry = array();
	}
	return $registry;
    }

    /**
     * Get the static factory registry
     *
     * @return array factory data
     * @access private
     * @staticvar array $registry The only factory registry we will need
     * @static
     */
    function &_getFactoryData() {
	global $gallery;
	static $registry;
	$registry =& GalleryFactoryHelper_simple::_getSingleton();
	if (empty($registry)) {
	    $storage =& $gallery->getStorage();
	    $cacheParams = array('type' => 'module',
				 'itemId' => 'GalleryFactoryHelper_loadRegistry',
				 'id' => '_all');

	    /* Don't get by reference here, it'll detach $registry from the singleton */
	    $registry = GalleryDataCache::getFromDisk($cacheParams);
	    if (!isset($registry)) {
		$query = '
                SELECT
                  [GalleryFactoryMap::classType],
                  [GalleryFactoryMap::className],
                  [GalleryFactoryMap::implId],
                  [GalleryFactoryMap::implPath],
                  [GalleryFactoryMap::hints]
                FROM
                  [GalleryFactoryMap]
                ORDER BY
                  [GalleryFactoryMap::orderWeight] ASC
                ';
		list ($ret, $searchResults) = $gallery->search($query);
		if ($ret->isError()) {
		    $ret = array($ret->wrap(__FILE__, __LINE__), null);
		    return $ret;
		}

		while ($result = $searchResults->nextResult()) {
		    $registry['implementations'][$result[0]][$result[1]] = $result[3];
		    $registry['ids'][$result[0]][$result[2]] = $result[1];

		    $hints = unserialize($result[4]);
		    if (isset($hints)) {
			foreach ($hints as $hint) {
			    $registry['hints'][$result[0]][$hint][$result[2]] = $result[1];
			}
		    }
		}
		GalleryDataCache::putToDisk($cacheParams, $registry);
	    }
	}

	$ret = array(GalleryStatus::success(), &$registry);
	return $ret;
    }

    /**
     * Create a new instance of the given type based on the hint(s) provided
     *
     * @param string the class type (eg. 'GalleryGraphics')
     * @param array of hints to try (in order) or string, a single hint (eg. 'image/jpeg')
     * @return array object GalleryStatus a status code,
     *               object an instance
     * @static
     */
    function newInstanceByHint($classType, $hints) {
	list ($ret, $registry) = GalleryFactoryHelper_simple::_getFactoryData();
	if ($ret->isError()) {
	    return array($ret->wrap(__FILE__, __LINE__), null);
	}
	if (!is_array($hints)) {
	    $hints = array($hints);
	}
	$hints[] = '*';

	foreach ($hints as $hint) {
	    $hint = strtolower($hint);
	    if (!empty($registry['hints'][$classType][$hint])) {
		$classNames = array_values($registry['hints'][$classType][$hint]);
		break;
	    }
	}
	if (!isset($classNames)) {
	    return array(GalleryStatus::success(), null);
	}

	/* Right now we just use the first available hint */
	$className = $classNames[0];
	list ($ret, $instance) = GalleryFactoryHelper_simple::newInstance($classType, $className);
	if ($ret->isError()) {
	    return array($ret->wrap(__FILE__, __LINE__), null);
	}

	return array(GalleryStatus::success(), $instance);
    }

    /**
     * Create a new instance of the given type
     *
     * @param string the class type (eg. 'GalleryGraphics')
     * @param string the class name (eg. 'NetPbmGraphics')
     * @return object GalleryStatus a status code
     *         object the instance
     * @static
     */
    function newInstance($classType, $className=null) {
	global $gallery;

	list ($ret, $registry) = GalleryFactoryHelper_simple::_getFactoryData();
	if ($ret->isError()) {
	    return array($ret->wrap(__FILE__, __LINE__), null);
	}

	if (!isset($className)) {
	    if (empty($registry['implementations'][$classType])) {
		if ($gallery->getDebug()) {
		    $gallery->debug("Unimplemented: $classType");
		}
		return array(GalleryStatus::success(), null);
	    }
	    $classNames = array_keys($registry['implementations'][$classType]);
	    $className = $classNames[0];
	}

	if (empty($registry['implementations'][$classType][$className])) {
	    if ($gallery->getDebug()) {
		$gallery->debug("Unimplemented: $classType, $className");
	    }
	    return array(GalleryStatus::success(), null);
	}

	if (!class_exists($className)) {
	    $relativePath = $registry['implementations'][$classType][$className];

	    $platform = $gallery->getPlatform();
	    if (!$platform->file_exists(dirname(__FILE__) . '/../../../../' . $relativePath)) {
		return array(GalleryStatus::error(ERROR_BAD_PATH, __FILE__, __LINE__,
						  "Invalid path: $relativePath"),
			     null);
	    }

	    GalleryCoreApi::relativeRequireOnce($relativePath);

	    if (!class_exists($className)) {
		return array(GalleryStatus::error(ERROR_BAD_PARAMETER, __FILE__, __LINE__,
						  "Missing class: $className"),
			     null);
	    }
	}

	return array(GalleryStatus::success(), new $className);
    }
}
?>