/*
 *  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.clustering;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.Attributes;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.table.AttributeFactory;
import com.rapidminer.example.table.DoubleArrayDataRow;
import com.rapidminer.example.table.MemoryExampleTable;
import com.rapidminer.example.table.NominalMapping;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.ports.InputPort;
import com.rapidminer.operator.ports.OutputPort;
import com.rapidminer.operator.ports.metadata.ExampleSetMetaData;
import com.rapidminer.operator.ports.metadata.GenerateNewMDRule;
import com.rapidminer.operator.ports.metadata.MDInteger;
import com.rapidminer.operator.ports.metadata.MetaData;
import com.rapidminer.operator.ports.metadata.ModelMetaData;
import com.rapidminer.tools.Ontology;

/**
 * This operator extracts the cluster prototypes from a flat 
 * clustermodel and builds an example set containing them.
 * 
 * @author Sebastian Land
 *
 */
public class ExtractClusterPrototypes extends Operator {

	private InputPort modelInput = getInputPorts().createPort("model", CentroidClusterModel.class);
	private OutputPort exampleSetOutput = getOutputPorts().createPort("example set");
	private OutputPort modelOutput = getOutputPorts().createPort("model");

	
	public ExtractClusterPrototypes(OperatorDescription description) {
		super(description);
		
		getTransformer().addPassThroughRule(modelInput, modelOutput);
		getTransformer().addRule(new GenerateNewMDRule(exampleSetOutput, ExampleSet.class) {
			@Override
			public MetaData modifyMetaData(MetaData unmodifiedMetaData) {
				if (modelInput.getMetaData() instanceof ModelMetaData) {
					ModelMetaData modelMetaData = (ModelMetaData) modelInput.getMetaData();
					ExampleSetMetaData emd = modelMetaData.getTrainingSetMetaData();
					emd.setNumberOfExamples(new MDInteger());
					return emd;
				}
				return super.modifyMetaData(unmodifiedMetaData);
			}
		});
	}

	@Override
	public void doWork() throws OperatorException {
		CentroidClusterModel model = modelInput.getData();
		
		Attributes trainAttributes = model.getTrainingHeader().getAttributes();
		String[] attributeNames = model.getAttributeNames();
		Attribute[] attributes = new Attribute[attributeNames.length + 1];
		for (int i = 0; i < attributeNames.length; i++) {
			Attribute originalAttribute = trainAttributes.get(attributeNames[i]);
			attributes[i] = AttributeFactory.createAttribute(attributeNames[i], originalAttribute.getValueType());
			if (originalAttribute.isNominal()) {
				attributes[i].setMapping((NominalMapping) originalAttribute.getMapping().clone());
			}
		}
		Attribute clusterAttribute = AttributeFactory.createAttribute("cluster", Ontology.NOMINAL);
		attributes[attributes.length - 1] = clusterAttribute;
		
		MemoryExampleTable table = new MemoryExampleTable(attributes);
		for (int i = 0; i < model.getNumberOfClusters(); i++) {
			double[] data = new double[attributeNames.length + 1];
			System.arraycopy(model.getCentroidCoordinates(i), 0, data, 0, attributeNames.length);
			data[attributeNames.length] = clusterAttribute.getMapping().mapString("cluster_" + i);
			table.addDataRow(new DoubleArrayDataRow(data));
		}
		
		ExampleSet resultSet = table.createExampleSet();
		resultSet.getAttributes().setSpecialAttribute(clusterAttribute, Attributes.CLUSTER_NAME);
		
		modelOutput.deliver(model);
		exampleSetOutput.deliver(resultSet);
	}
	
}