// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-

//-----------------------------------------------------------------------------
// moeoObjectiveVectorTraits.h
// (c) OPAC Team (LIFL), Dolphin Project (INRIA), 2007
/*
    This library...

    Contact: paradiseo-help@lists.gforge.inria.fr, http://paradiseo.gforge.inria.fr
 */
//-----------------------------------------------------------------------------

#ifndef MOEOOBJECTIVEVECTORTRAITS_H_
#define MOEOOBJECTIVEVECTORTRAITS_H_

#include <vector>
#include <iostream>
#include <stdexcept>

/**
 * A traits class for moeoObjectiveVector to specify the number of objectives and which ones have to be minimized or maximized.
 */
class moeoObjectiveVectorTraits
{
public:

	/** The tolerance value (used to compare solutions) */
	const static double tol = 1e-6;
	
	/**
	 * Parameters setting
	 * @param _nObjectives the number of objectives
	 * @param _bObjectives the min/max vector (true = min / false = max)
	 */
	static void setup(unsigned _nObjectives, std::vector < bool > & _bObjectives)
	{
		// in case the number of objectives was already set to a different value
		if ( nObj && (nObj != _nObjectives) ) {
			std::cout << "WARNING\n";
			std::cout << "WARNING : the number of objectives are changing\n";
			std::cout << "WARNING : Make sure all existing objects are destroyed\n";
			std::cout << "WARNING\n";
		}
		// number of objectives
		nObj = _nObjectives;
		// min/max vector
		bObj = _bObjectives;
		// in case the number of objectives and the min/max vector size don't match
		if (nObj != bObj.size())
			throw std::runtime_error("Number of objectives and min/max size don't match in moeoObjectiveVectorTraits::setup");
	}
	
	/**
	 * Returns the number of objectives
	 */
	static unsigned nObjectives()
	{
		// in case the number of objectives would not be assigned yet		
		if (! nObj)
			throw std::runtime_error("Number of objectives not assigned in moeoObjectiveVectorTraits");		
		return nObj;
	}
	
	/**
	 * Returns true if the _ith objective have to be minimized
	 * @param _i  the index
	 */
	static bool minimizing(unsigned _i)
	{
		// in case there would be a wrong index
		if (_i >= bObj.size())
			throw std::runtime_error("Wrong index in moeoObjectiveVectorTraits");
		return bObj[_i];
	}
	
	/**
	 * Returns true if the _ith objective have to be maximized
	 * @param _i  the index
	 */
	static bool maximizing(unsigned _i) {
		return (! minimizing(_i));
	}
		
	/**
	 * Returns the tolerance value (to compare solutions)
	 */
	static double tolerance()
	{
		return tol;
	}


private:

	/** The number of objectives */
	static unsigned nObj;
	/** The min/max vector */
	static std::vector < bool > bObj;
		
};

#endif /*MOEOOBJECTIVEVECTORTRAITS_H_*/


// The static variables of the moeoObjectiveVectorTraits class need to be allocated
// (maybe it would have been better to put this on a moeoObjectiveVectorTraits.cpp file)
unsigned moeoObjectiveVectorTraits::nObj;
std::vector < bool > moeoObjectiveVectorTraits::bObj;