<?php
/**
 * A factory class for file-based stack indexes
 *
 * @author		Roland Haeder <webmaster@ship-simu.org>
 * @version		0.0.0
 * @copyright	Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 Hub Developer Team
 * @license		GNU GPL 3.0 or any newer version
 * @link		http://www.ship-simu.org
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */
class FileStackIndexFactory extends ObjectFactory {
	/**
	 * Protected constructor
	 *
	 * @return	void
	 */
	protected function __construct () {
		// Call parent constructor
		parent::__construct(__CLASS__);
	}

	/**
	 * Returns a singleton (registry-based) StackableFile instance
	 *
	 * @param	$stackName			Name of the stack's file
	 * @return	$indexInstance		An instance of a IndexableStack class
	 */
	public static final function createFileStackIndexInstance ($fileName, $type) {
		// If there is no handler?
		if (Registry::getRegistry()->instanceExists($type . '_index')) {
			// Get handler from registry
			$indexInstance = Registry::getRegistry()->getInstance($type . '_index');
		} else {
			// Get the handler instance
			$indexInstance = self::createObjectByConfiguredName('file_stack_' . $type . '_index_class', array($fileName));

			// Add it to the registry
			Registry::getRegistry()->addInstance($type . '_index', $indexInstance);
		}

		// Return the instance
		return $indexInstance;
	}
}

// [EOF]
?>