/* -*- C++ -*-

 *

 * This file is a part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2003-2008

 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_LP_GLPK_H

#define LEMON_LP_GLPK_H

///\file

///\brief Header of the LEMON-GLPK lp solver interface.

///\ingroup lp_group

#include <lemon/lp_base.h>

extern "C" {

#include <glpk.h>

}

namespace lemon {

  /// \brief Interface for the GLPK LP solver

  /// 

  /// This class implements an interface for the GLPK LP solver.

  ///\ingroup lp_group

  class LpGlpk : virtual public LpSolverBase {

  protected:

    LPX* lp;

    bool solved;

  public:

    typedef LpSolverBase Parent;

    LpGlpk();

    LpGlpk(const LpGlpk &);

    ~LpGlpk();

  protected:

    virtual LpSolverBase* _newLp();

    virtual LpSolverBase* _copyLp();

    virtual int _addCol();

    virtual int _addRow();

    virtual void _eraseCol(int i);

    virtual void _eraseRow(int i);

    virtual void _getColName(int col, std::string & name) const;

    virtual void _setColName(int col, const std::string & name);

    virtual int _colByName(const std::string& name) const;

    virtual void _setRowCoeffs(int i, ConstRowIterator b, ConstRowIterator e);

    virtual void _getRowCoeffs(int i, RowIterator b) const;

    virtual void _setColCoeffs(int i, ConstColIterator b, ConstColIterator e);

    virtual void _getColCoeffs(int i, ColIterator b) const;

    virtual void _setCoeff(int row, int col, Value value);

    virtual Value _getCoeff(int row, int col) const;

    virtual void _setColLowerBound(int i, Value value);

    virtual Value _getColLowerBound(int i) const;

    virtual void _setColUpperBound(int i, Value value);

    virtual Value _getColUpperBound(int i) const;

    virtual void _setRowBounds(int i, Value lower, Value upper);

    virtual void _getRowBounds(int i, Value &lb, Value &ub) const;

    virtual void _setObjCoeff(int i, Value obj_coef);

    virtual Value _getObjCoeff(int i) const;

    virtual void _clearObj();

    ///\e

    ///\todo It should be clarified

    ///

    virtual SolveExitStatus _solve();

    virtual Value _getPrimal(int i) const;

    virtual Value _getDual(int i) const;

    virtual Value _getPrimalValue() const;

    virtual bool _isBasicCol(int i) const;

    ///\e

    ///\todo It should be clarified

    ///

    virtual SolutionStatus _getPrimalStatus() const;

    virtual SolutionStatus _getDualStatus() const;

    virtual ProblemTypes _getProblemType() const;

    virtual void _setMax();

    virtual void _setMin();

    virtual bool _isMax() const;

  public:

    ///Set the verbosity of the messages

    ///Set the verbosity of the messages

    ///

    ///\param m is the level of the messages output by the solver routines.

    ///The possible values are:

    ///- 0 --- no output (default value)

    ///- 1 --- error messages only

    ///- 2 --- normal output

    ///- 3 --- full output (includes informational messages)

    void messageLevel(int m);

    ///Turns on or off the presolver

    ///Turns on (\c b is \c true) or off (\c b is \c false) the presolver

    ///

    ///The presolver is off by default.

    void presolver(bool b);

    ///Pointer to the underlying GLPK data structure.

    LPX *lpx() {return lp;}

    ///Returns the constraint identifier understood by GLPK.

    int lpxRow(Row r) { return _lpId(r); }

    ///Returns the variable identifier understood by GLPK.

    int lpxCol(Col c) { return _lpId(c); }

  };

} //END OF NAMESPACE LEMON

#endif //LEMON_LP_GLPK_H