/*
 <moTwoOptExNeighborhood.h>
 Copyright (C) DOLPHIN Project-Team, INRIA Lille - Nord Europe, 2006-2010
 
 Sébastien Verel, Arnaud Liefooghe, Jérémie Humeau
 
 This software is governed by the CeCILL license under French law and
 abiding by the rules of distribution of free software.  You can  ue,
 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".
 
 In this respect, the user's attention is drawn to the risks associated
 with loading,  using,  modifying and/or developing or reproducing the
 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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 encouraged to load and test the software's suitability as regards their
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 same conditions as regards security.
 The fact that you are presently reading this means that you have had
 knowledge of the CeCILL license and that you accept its terms.
 
 ParadisEO WebSite : http://paradiseo.gforge.inria.fr
 Contact: paradiseo-help@lists.gforge.inria.fr
 */

#ifndef _moTwoOptExNeighborhood_h
#define _moTwoOptExNeighborhood_h

#include <problems/permutation/moTwoOptExNeighbor.h>
#include <neighborhood/moNeighborhood.h>

#include <neighborhood/moIndexNeighborhood.h>

/**
 * Two-opt exchange neighborhood
 */

template <class EOT, class Fitness=typename EOT::Fitness>
class moTwoOptExNeighborhood : public moNeighborhood< moTwoOptExNeighbor<EOT,Fitness> >
{
public:
    typedef moTwoOptExNeighbor<EOT, Fitness> Neighbor;

    /**
     * @return true if there is at least an available neighbor
     */
    virtual bool hasNeighbor(EOT& _solution) {
        return (_solution.size() > 1);
    };

    /**
     * Initialization of the neighborhood
     * @param _solution the solution to explore
     * @param _current the first neighbor
     */
    virtual void init(EOT& _solution, Neighbor& _current) {
        indices.first=0;
        indices.second=1;
        _current.setIndices(0,1);
    }

    /**
     * Give the next neighbor
     * @param _solution the solution to explore
     * @param _current the next neighbor
     */
    virtual void next(EOT& _solution, Neighbor& _current) {
        if (indices.second==_solution.size()-1) {
            indices.first++;
            indices.second=indices.first+1;
        }
        else
            indices.second++;
        _current.setIndices(indices.first, indices.second);
    }

    /**
     * Test if there is again a neighbor
     * @param _solution the solution to explore
     * @return true if there is again a neighbor not explored
     */
    virtual bool cont(EOT& _solution) {
        return !((indices.first == (_solution.size()-2)) && (indices.second == (_solution.size()-1)));
    }

    /**
     * Return the class Name
     * @return the class name as a std::string
     */
    virtual std::string className() const {
        return "moTwoOptExNeighborhood";
    }

private:
    std::pair<unsigned int, unsigned int> indices;

};

#endif
