/**
 * Copyright (C) 2001-2017 by RapidMiner and the contributors
 * 
 * Complete list of developers available at our web site:
 * 
 * http://rapidminer.com
 * 
 * This program is free software: you can redistribute it and/or modify it under the terms of the
 * GNU Affero 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
 * Affero General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License along with this program.
 * If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.io.process;

import java.util.LinkedList;
import java.util.List;

import org.w3c.dom.Element;

import com.rapidminer.operator.ExecutionUnit;
import com.rapidminer.operator.Operator;


/**
 * Manages a list of {@link ProcessXMLFilter}s that is applied when parsing or writing process XML
 * data.
 * 
 * @author Simon Fischer, Michael Knopf
 */
public class ProcessXMLFilterRegistry {

	/** Lock for modifying the list of filters. */
	private static final Object FILTER_LOCK = new Object();

	/** List of filters to be applied. */
	private static final List<ProcessXMLFilter> FILTERS = new LinkedList<>();

	/**
	 * Register a new {@link ProcessXMLFilter}.
	 * 
	 * @param filter
	 *            The filter to be registered.
	 */
	public static void registerFilter(ProcessXMLFilter filter) {
		synchronized (FILTER_LOCK) {
			FILTERS.add(filter);
		}
	}

	protected static void fireOperatorExported(Operator operator, Element element) {
		for (ProcessXMLFilter filter : FILTERS) {
			filter.operatorExported(operator, element);
		}
	}

	protected static void fireOperatorImported(Operator operator, Element element) {
		for (ProcessXMLFilter filter : FILTERS) {
			filter.operatorImported(operator, element);
		}
	}

	protected static void fireExecutionUnitExported(ExecutionUnit unit, Element element) {
		for (ProcessXMLFilter filter : FILTERS) {
			filter.executionUnitExported(unit, element);
		}
	}

	protected static void fireExecutionUnitImported(ExecutionUnit unit, Element element) {
		for (ProcessXMLFilter filter : FILTERS) {
			filter.executionUnitImported(unit, element);
		}
	}

}