/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.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.operator;

import com.rapidminer.operator.ports.InputPort;
import com.rapidminer.operator.ports.OutputPort;
import com.rapidminer.operator.ports.metadata.CollectionMetaData;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.ports.metadata.GenerateNewMDRule;
import com.rapidminer.operator.ports.metadata.ModelMetaData;

/**
 * <p>This operator ungroups a previously grouped model ({@link ModelGrouper}) and
 * delivers the grouped input models.</p>
 * 
 * <p>This operator replaces the automatic model grouping known from previous
 * versions of RapidMiner. The explicit usage of this ungrouping operator gives
 * the user more control about the ungrouping procedure. Single models can 
 * be grouped with the {@link ModelGrouper} operator.</p>
 * 
 * @author Ingo Mierswa
 */
public class ModelUngrouper extends Operator {

	private InputPort groupedModelInput = getInputPorts().createPort("grouped model", GroupedModel.class);
	private OutputPort modelOutput = getOutputPorts().createPort("models");

	public ModelUngrouper(OperatorDescription description) {
		super(description);
		getTransformer().addRule(new GenerateNewMDRule(modelOutput, new CollectionMetaData(new ModelMetaData(Model.class, new ExampleSetMetaData()))));
	}

	@Override
	public void doWork() throws OperatorException {
		GroupedModel groupedModel = groupedModelInput.getData();
		Model[] result = new Model[groupedModel.getNumberOfModels()];
		int index = 0;
		for (Model inner : groupedModel) {
			result[index++] = inner;
		}	
		modelOutput.deliver(new IOObjectCollection<Model>(result));
	}
}