/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2008 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.generator;

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

import com.rapidminer.tools.RandomGenerator;


/** The label is positive if the sum of both arguments is positive and negative otherwise.
 *  In addition, several local patterns in different sizes are placed in the data space. 
 * 
 *  @author Ingo Mierswa
 *  @version $Id: GlobalAndLocalPatternsFunction.java,v 1.3 2008/05/09 19:22:51 ingomierswa Exp $
 */
public class GlobalAndLocalPatternsFunction extends ClassificationFunction {

    private static final int NUMBER_OF_POSITIVE_DOTS = 8;

    private static final int NUMBER_OF_NEGATIVE_DOTS = 5;

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

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

    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("Global and Local Patterns Function", "needs exactly two attributes!");
        
        Iterator p = positiveDots.iterator();
        while (p.hasNext()) {
            Dot pDot = (Dot) p.next();
            if (pDot.contains(att[0], att[1])) {
                return getLabel().getMapping().mapString("positive");
            }
        }
        Iterator n = negativeDots.iterator();
        while (n.hasNext()) {
            Dot nDot = (Dot) n.next();
            if (nDot.contains(att[0], att[1])) {
                return getLabel().getMapping().mapString("negative");
            }
        }

        // global model
        double sum = 0.0d;
        for (int i = 0; i < att.length; i++)
            sum += att[i];
        return (sum > 0 ? getLabel().getMapping().mapString("positive") : getLabel().getMapping().mapString("negative"));        
    }
}