/*
 *  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.generator;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import com.rapidminer.tools.RandomGenerator;


/**
 * Returns a classification function with one major class and a set of dots
 * of the second class.
 * 
 * @author Ingo Mierswa
 */
public class RandomDotsClassificationFunction extends ClassificationFunction {

	private static final int NUMBER_OF_POSITIVE_DOTS = 10;

	private static final int NUMBER_OF_NEGATIVE_DOTS = 5;

	private List<Dot> positiveDots = new LinkedList<Dot>();

	private List<Dot> negativeDots = new LinkedList<Dot>();

	@Override
	public void init(RandomGenerator random) {
		positiveDots.clear();
		negativeDots.clear();
		double maxRadius = (upper - lower) / NUMBER_OF_POSITIVE_DOTS;
		for (int i = 0; i < NUMBER_OF_POSITIVE_DOTS; i++) {
			positiveDots.add(new Dot(random.nextDoubleInRange(lower, upper), random.nextDoubleInRange(lower, upper), random.nextDoubleInRange(0, maxRadius)));
		}
		for (int i = 0; i < NUMBER_OF_NEGATIVE_DOTS; i++) {
			negativeDots.add(new Dot(random.nextDoubleInRange(lower, upper), random.nextDoubleInRange(lower, upper), random.nextDoubleInRange(0, maxRadius)));
		}
	}

	public double calculate(double[] att) throws FunctionException {
		if (att.length != 2)
			throw new FunctionException("Random Dot classification function", "needs 2 attributes!");
		Iterator p = positiveDots.iterator();
		while (p.hasNext()) {
			Dot pDot = (Dot) p.next();
			if (pDot.contains(att[0], att[1])) {
				Iterator n = negativeDots.iterator();
				boolean negative = false;
				while (n.hasNext()) {
					Dot nDot = (Dot) n.next();
					if (nDot.contains(att[0], att[1])) {
						negative = true;
						break;
					}
				}
				if (negative)
					return getLabel().getMapping().mapString("negative");
				else
					return getLabel().getMapping().mapString("positive");
			}
		}
		return getLabel().getMapping().mapString("negative");
	}

	@Override
	public int getMinNumberOfAttributes() {
		return 2;
	}

	@Override
	public int getMaxNumberOfAttributes() {
		return 2;
	}
}