/*
* <moeoFrontByFrontSharingDiversityAssignment.h>
* Copyright (C) DOLPHIN Project-Team, INRIA Futurs, 2006-2007
* (C) OPAC Team, LIFL, 2002-2007
*
* Arnaud Liefooghe
*
* This software is governed by the CeCILL license under French law and
* abiding by the rules of distribution of free software.  You can  use,
* modify and/ or redistribute the software under the terms of the CeCILL
* license as circulated by CEA, CNRS and INRIA at the following URL
* "http://www.cecill.info".
*
* As a counterpart to the access to the source code and  rights to copy,
* modify and redistribute granted by the license, users are provided only
* with a limited warranty  and the software's author,  the holder of the
* economic rights,  and the successive licensors  have only  limited liability.
*
* In this respect, the user's attention is drawn to the risks associated
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* software by the user in light of its specific status of free software,
* that may mean  that it is complicated to manipulate,  and  that  also
* therefore means  that it is reserved for developers  and  experienced
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*
* ParadisEO WebSite : http://paradiseo.gforge.inria.fr
* Contact: paradiseo-help@lists.gforge.inria.fr
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*/
//-----------------------------------------------------------------------------

#ifndef MOEOFRONTBYFRONTSHARINGDIVERSITYASSIGNMENT_H_
#define MOEOFRONTBYFRONTSHARINGDIVERSITYASSIGNMENT_H_

#include <diversity/moeoSharingDiversityAssignment.h>

/**
 * Sharing assignment scheme on the way it is used in NSGA.
 */
template < class MOEOT >
class moeoFrontByFrontSharingDiversityAssignment : public moeoSharingDiversityAssignment < MOEOT >
  {
  public:

    /** the objective vector type of the solutions */
    typedef typename MOEOT::ObjectiveVector ObjectiveVector;


    /**
     * Ctor
     * @param _distance the distance used to compute the neighborhood of solutions (can be related to the decision space or the objective space)
     * @param _nicheSize neighborhood size in terms of radius distance (closely related to the way the distances are computed)
     * @param _alpha parameter used to regulate the shape of the sharing function
     */
    moeoFrontByFrontSharingDiversityAssignment(moeoDistance<MOEOT,double> & _distance, double _nicheSize = 0.5, double _alpha = 2.0) : moeoSharingDiversityAssignment < MOEOT >(_distance, _nicheSize, _alpha)
    {}


    /**
     * Ctor with an euclidean distance (with normalized objective values) in the objective space is used as default
     * @param _nicheSize neighborhood size in terms of radius distance (closely related to the way the distances are computed)
     * @param _alpha parameter used to regulate the shape of the sharing function
     */
    moeoFrontByFrontSharingDiversityAssignment(double _nicheSize = 0.5, double _alpha = 2.0) : moeoSharingDiversityAssignment < MOEOT >(_nicheSize, _alpha)
    {}


    /**
     * @warning NOT IMPLEMENTED, DO NOTHING !
     * Updates the diversity values of the whole population _pop by taking the deletion of the objective vector _objVec into account.
     * @param _pop the population
     * @param _objVec the objective vector
     * @warning NOT IMPLEMENTED, DO NOTHING !
     */
    void updateByDeleting(eoPop < MOEOT > & /*_pop*/, ObjectiveVector & /*_objVec*/)
    {
      std::cout << "WARNING : updateByDeleting not implemented in moeoSharingDiversityAssignment" << std::endl;
    }


  private:

    using moeoSharingDiversityAssignment < MOEOT >::distance;
    using moeoSharingDiversityAssignment < MOEOT >::nicheSize;
    using moeoSharingDiversityAssignment < MOEOT >::sh;


    /**
     * Sets similarities FRONT BY FRONT for every solution contained in the population _pop
     * @param _pop the population
     */
    void setSimilarities(eoPop < MOEOT > & _pop)
    {
      // compute distances between every individuals
      moeoDistanceMatrix < MOEOT , double > dMatrix (_pop.size(), distance);
      dMatrix(_pop);
      // sets the distance to bigger than the niche size for every couple of solutions that do not belong to the same front
      for (unsigned int i=0; i<_pop.size(); i++)
        {
          for (unsigned int j=0; j<i; j++)
            {
              if (_pop[i].fitness() != _pop[j].fitness())
                {
                  dMatrix[i][j] = nicheSize;
                  dMatrix[j][i] = nicheSize;
                }
            }
        }
      // compute similarities
      double sum;
      for (unsigned int i=0; i<_pop.size(); i++)
        {
          sum = 0.0;
          for (unsigned int j=0; j<_pop.size(); j++)
            {
              sum += sh(dMatrix[i][j]);
            }
          _pop[i].diversity(sum);
        }
    }

  };

#endif /*MOEOFRONTBYFRONTSHARINGDIVERSITYASSIGNMENT_H_*/