/*
 *  Open BEAGLE
 *  Copyright (C) 2001-2005 by Christian Gagne and Marc Parizeau
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  Contact:
 *  Laboratoire de Vision et Systemes Numeriques
 *  Departement de genie electrique et de genie informatique
 *  Universite Laval, Quebec, Canada, G1K 7P4
 *  http://vision.gel.ulaval.ca
 *
 */

/*!
 *  \file   beagle/src/SelectRouletteOp.cpp
 *  \brief  Source code of class SelectRouletteOp.
 *  \author Christian Gagne
 *  \author Marc Parizeau
 *  $Revision: 1.8 $
 *  $Date: 2005/10/04 16:25:10 $
 */
 
#include "beagle/Beagle.hpp"

using namespace Beagle;


/*!
 *  \brief Construct a proportionnal roulette selection operator.
 *  \param inReproProbaName Reproduction probability parameter name used in register.
 *  \param inName Name of the proportionnal roulette selection operator.
 */
SelectRouletteOp::SelectRouletteOp(Beagle::string inReproProbaName, Beagle::string inName) :
  SelectionOp(inReproProbaName, inName),
  mRouletteValid(false)
{ }


/*!
 *  \brief Apply roulette selection operation.
 *  \param ioDeme Deme on which roulette selection is applied.
 *  \param ioContext Evolutionary context.
 */
void SelectRouletteOp::operate(Deme& ioDeme, Context& ioContext)
{
  Beagle_StackTraceBeginM();
  mRoulette.clear();
  for(Individual::Bag::size_type i=0; i<ioDeme.size(); ++i) {
    Beagle_NonNullPointerAssertM(ioDeme[i]);
    FitnessSimple::Handle lFitness = castHandleT<FitnessSimple>(ioDeme[i]->getFitness());
    mRoulette.insert(i, lFitness->getValue());
  }
  mRoulette.optimize();
  mRouletteValid = true;
  SelectionOp::operate(ioDeme, ioContext);
  mRouletteValid = false;
  Beagle_StackTraceEndM("void SelectRouletteOp::operate(Deme& ioDeme, Context& ioContext)");
}


/*!
 *  \brief Select an individual using proportional roulette selection.
 *  \param ioPool Pool of individuals on which roulette selection is applied.
 *  \param ioContext Evolutionary context.
 *  \warning To use roulette selection, every individuals composing the population must have
 *    non-negative fitness value. Roulette selection is valid only with FitnessSimple object
 *    and derived (FitnessSimpleMin, FitnessKoza).
 */
unsigned int SelectRouletteOp::selectIndividual(Individual::Bag& ioPool, Context& ioContext)
{
  Beagle_StackTraceBeginM();
  if(ioPool.size() == 0) return 0;
  if(mRouletteValid == false) {
    mRoulette.clear();
    for(Individual::Bag::size_type i=0; i<ioPool.size(); ++i) {
      Beagle_NonNullPointerAssertM(ioPool[i]);
      FitnessSimple::Handle lFitness = castHandleT<FitnessSimple>(ioPool[i]->getFitness());
      mRoulette.insert(i, lFitness->getValue());
    }
  }
  return mRoulette.select(ioContext.getSystem().getRandomizer());
  Beagle_StackTraceEndM("unsigned int SelectRouletteOp::selectIndividual(Individual::Bag& ioPool, Context& ioContext)");
}