/*
 *  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.features.selection;

import java.io.File;

import com.rapidminer.example.AttributeWeights;
import com.rapidminer.operator.features.Individual;
import com.rapidminer.operator.features.Population;
import com.rapidminer.operator.features.PopulationOperator;
import com.rapidminer.operator.io.AttributeWeightsWriter;
import com.rapidminer.tools.OperatorService;

/**
 * This population operator writes the currently best weights into the specified file.
 * 
 * @author Ingo Mierswa
 */
public class SaveIntermediateWeights implements PopulationOperator {

	private int whichGeneration;
	
	private AbstractGeneticAlgorithm operator;
	
	private String[] attributeNames;
	
	public SaveIntermediateWeights(AbstractGeneticAlgorithm operator, int whichGeneration, String[] attributeNames) {
		this.operator = operator;
		this.whichGeneration = whichGeneration;
		this.attributeNames = attributeNames;
	}
	
	public void operate(Population pop) throws Exception {
		Individual bestIndividual = pop.getBestIndividualEver();
		if (bestIndividual != null) {
			File outputFile = operator.getParameterAsFile(AbstractGeneticAlgorithm.PARAMETER_INTERMEDIATE_WEIGHTS_FILE, true);
			if (outputFile != null) {
				AttributeWeightsWriter writer = OperatorService.createOperator(AttributeWeightsWriter.class);
				writer.setParameter(AttributeWeightsWriter.PARAMETER_ATTRIBUTE_WEIGHTS_FILE, outputFile.getAbsolutePath());

				double[] weightValues = bestIndividual.getWeights();
				if (weightValues.length == attributeNames.length) {
					AttributeWeights weights = new AttributeWeights();
					for (int i = 0; i < weightValues.length; i++) {
						weights.setWeight(attributeNames[i], weightValues[i]);
					}
					writer.write(weights); 
				}
			}
		}
	}

	public boolean performOperation(int generation) {
		if ((generation % whichGeneration) == 0) {
			return true;
		} else {
			return false;
		}
	}
}