/*
 *  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.weighting;

import java.util.List;

import com.rapidminer.example.AttributeWeights;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.Model;
import com.rapidminer.operator.OperatorCapability;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.features.transformation.ComponentWeightsCreatable;
import com.rapidminer.operator.ports.InputPort;
import com.rapidminer.operator.ports.OutputPort;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeInt;


/**
 * For models creating components like <code>PCA</code>, <code>GHA</code>
 * and <code>FastICA</code> you can create the <code>AttributeWeights</code>
 * from a component.
 * 
 * @author Daniel Hakenjos, Ingo Mierswa
 */
public class ComponentWeights extends AbstractWeighting {

	private InputPort modelInput = getInputPorts().createPort("model", Model.class);
	private OutputPort modelOutput = getOutputPorts().createPort("model");

	/** The parameter name for "Create the weights of this component." */
	public static final String PARAMETER_COMPONENT_NUMBER = "component_number";

	public ComponentWeights(OperatorDescription description) {
		super(description);
		getTransformer().addPassThroughRule(modelInput, modelOutput);
	}

	/** Helper method for anonymous instantiations of this class. 
	 */
	public AttributeWeights doWork(Model model, ExampleSet exampleSet) throws OperatorException {
		modelInput.receive(model);
		getExampleSetInputPort().receive(exampleSet);
		doWork();
		return getWeightsOutputPort().getData();
	}

	@Override
	protected AttributeWeights calculateWeights(ExampleSet exampleSet) throws OperatorException {
		Model model = modelInput.getData();

		if (!(model instanceof ComponentWeightsCreatable)) {
			throw new OperatorException(getName() + ": needs an input model wich implements the ComponentWeightsCreatable interface:" + model.getClass().getName());
		}

		int component = getParameterAsInt(PARAMETER_COMPONENT_NUMBER);
		AttributeWeights weights = ((ComponentWeightsCreatable) model).getWeightsOfComponent(component);

		// normalize
		if (getParameterAsBoolean(PARAMETER_NORMALIZE_WEIGHTS)) {
			weights.normalize();
		}

		modelOutput.deliver(model);
		return weights;
	}

	@Override
	protected boolean isExampleSetMandatory() {
		return false;
	}

	@Override
	public boolean supportsCapability(OperatorCapability capability) {
		return true; //unimportant since exampleset is mandatory
	}

	@Override
	public List<ParameterType> getParameterTypes() {
		List<ParameterType> list = super.getParameterTypes();
		list.addAll(super.getParameterTypes());
		list.add(new ParameterTypeInt(PARAMETER_COMPONENT_NUMBER, "Create the weights of this component.", 1, Integer.MAX_VALUE, 1));
		return list;
	}
}