// Catalano Genetic Library
// The Catalano Framework
//
// Copyright © Diego Catalano, 2012-2016
// diego.catalano at live.com
//
//
//    This library is free software; you can redistribute it and/or
//    modify it under the terms of the GNU Lesser General Public
//    License as published by the Free Software Foundation; either
//    version 2.1 of the License, or (at your option) any later version.
//
//    This library 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
//    Lesser General Public License for more details.
//
//    You should have received a copy of the GNU Lesser General Public
//    License along with this library; if not, write to the Free Software
//    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
//

package Catalano.Evolutionary.Genetic.Mutation;

import Catalano.Core.ArraysUtil;
import Catalano.Evolutionary.Genetic.Chromosome.IChromosome;
import java.util.Random;

/**
 * Scramble Mutation.
 * 
 * Support: Binary/Permuation/Integer/Double/Float Chromosome.
 * 
 * @author Diego Catalano
 */
public class ScrambleMutation implements IMutation{

    /**
     * Initializes a new instance of the ScrambleMutation class.
     */
    public ScrambleMutation() {}

    @Override
    public IChromosome Compute(IChromosome chromossome) {
        Random rand = new Random();
        
        IChromosome c = chromossome.Clone();
        
        int lenght = c.getLength();
        
        int a = rand.nextInt(lenght/2);
        int b = rand.nextInt(lenght/2) + lenght/2;
        
        int size = Math.abs(a-b) + 1;
        
        Object[] elem = new Object[size];
        for (int i = 0; i < size; i++) {
            elem[i] = c.getGene(i+a);
        }
        
        ArraysUtil.Shuffle(elem);
        
        for (int i = 0; i < size; i++) {
            c.setGene(i+a, elem[elem.length - i - 1]);
        }
        
        return c;
    }
    
}