/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 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.operator.meta;

import java.util.List;

import com.rapidminer.example.ExampleSet;
import com.rapidminer.example.set.SplittedExampleSet;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.ports.metadata.MDInteger;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeCategory;
import com.rapidminer.parameter.ParameterTypeDouble;
import com.rapidminer.parameter.UndefinedParameterError;
import com.rapidminer.tools.RandomGenerator;


/**
 * <p>An operator chain that split an {@link ExampleSet} into two disjunct parts
 * and applies the first child operator on the first part and applies the second
 * child on the second part and the result of the first child. The total result
 * is the result of the second operator.</p>
 * 
 * <p>The input example set will be splitted based on a defined ratio between 
 * 0 and 1.</p>
 * 
 * @author Ingo Mierswa
 */
public class RatioSplitChain extends AbstractSplitChain {

	/** The parameter name for "Relative size of the training set." */
	public static final String PARAMETER_SPLIT_RATIO = "split_ratio";

	/** The parameter name for "Defines the sampling type of this operator." */
	public static final String PARAMETER_SAMPLING_TYPE = "sampling_type";

	public RatioSplitChain(OperatorDescription description) {
		super(description);
	}


	@Override
	protected MDInteger getNumberOfExamplesFirst(MDInteger numberOfExamples) throws UndefinedParameterError {
		return numberOfExamples.multiply(getParameterAsDouble(PARAMETER_SPLIT_RATIO));
	}

	@Override
	protected MDInteger getNumberOfExamplesSecond(MDInteger numberOfExamples) throws UndefinedParameterError {
		return numberOfExamples.multiply(1d - getParameterAsDouble(PARAMETER_SPLIT_RATIO));
	}

	@Override
	protected SplittedExampleSet createSplittedExampleSet(ExampleSet inputSet) throws OperatorException {
		return new SplittedExampleSet(inputSet, 
				getParameterAsDouble(PARAMETER_SPLIT_RATIO), 
				getParameterAsInt(PARAMETER_SAMPLING_TYPE), 
				getParameterAsBoolean(RandomGenerator.PARAMETER_USE_LOCAL_RANDOM_SEED), getParameterAsInt(RandomGenerator.PARAMETER_LOCAL_RANDOM_SEED));
	}

	@Override
	public List<ParameterType> getParameterTypes() {
		List<ParameterType> types = super.getParameterTypes();
		ParameterType type = new ParameterTypeDouble(PARAMETER_SPLIT_RATIO, "Relative size of the first set. The remaining examples will be part of the second set.", 0.0d, 1.0d, 0.7d);
		type.setExpert(false);
		types.add(type);
		types.add(new ParameterTypeCategory(PARAMETER_SAMPLING_TYPE, "Defines the sampling type of this operator.", SplittedExampleSet.SAMPLING_NAMES, SplittedExampleSet.SHUFFLED_SAMPLING));
		types.addAll(RandomGenerator.getRandomGeneratorParameters(this));
		return types;
	}

}