/* -*- mode: C++; indent-tabs-mode: nil; -*-

  *

  * 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>

 // forward declaration

 #ifndef _GLP_PROB

 #define _GLP_PROB

 typedef struct { double _prob; } glp_prob;

 /* LP/MIP problem object */

 #endif

 namespace lemon {

   /// \brief Base interface for the GLPK LP and MIP solver

   ///

   /// This class implements the common interface of the GLPK LP and MIP solver.

   /// \ingroup lp_group

   class GlpkBase : virtual public LpBase {

   protected:

     typedef glp_prob LPX;

     glp_prob* lp;

     GlpkBase();

     GlpkBase(const GlpkBase&);

     virtual ~GlpkBase();

   protected:

     virtual int _addCol();

     virtual int _addRow();

     virtual void _eraseCol(int i);

     virtual void _eraseRow(int i);

     virtual void _eraseColId(int i);

     virtual void _eraseRowId(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 _getRowName(int row, std::string& name) const;

     virtual void _setRowName(int row, const std::string& name);

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

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

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

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

     virtual void _getColCoeffs(int i, InsertIterator 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 _setRowLowerBound(int i, Value value);

     virtual Value _getRowLowerBound(int i) const;

     virtual void _setRowUpperBound(int i, Value value);

     virtual Value _getRowUpperBound(int i) const;

     virtual void _setObjCoeffs(ExprIterator b, ExprIterator e);

     virtual void _getObjCoeffs(InsertIterator b) const;

     virtual void _setObjCoeff(int i, Value obj_coef);

     virtual Value _getObjCoeff(int i) const;

     virtual void _setSense(Sense);

     virtual Sense _getSense() const;

     virtual void _clear();

   public:

     ///Pointer to the underlying GLPK data structure.

     LPX *lpx() {return lp;}

     ///Const pointer to the underlying GLPK data structure.

     const LPX *lpx() const {return lp;}

     ///Returns the constraint identifier understood by GLPK.

     int lpxRow(Row r) const { return rows(id(r)); }

     ///Returns the variable identifier understood by GLPK.

     int lpxCol(Col c) const { return cols(id(c)); }

   };

   /// \brief Interface for the GLPK LP solver

   ///

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

   ///\ingroup lp_group

   class LpGlpk : public GlpkBase, public LpSolver {

   public:

     ///\e

     LpGlpk();

     ///\e

     LpGlpk(const LpGlpk&);

   private:

     mutable std::vector<double> _primal_ray;

     mutable std::vector<double> _dual_ray;

     void _clear_temporals();

   protected:

     virtual LpGlpk* _cloneSolver() const;

     virtual LpGlpk* _newSolver() const;

     virtual const char* _solverName() const;

     virtual SolveExitStatus _solve();

     virtual Value _getPrimal(int i) const;

     virtual Value _getDual(int i) const;

     virtual Value _getPrimalValue() const;

     virtual VarStatus _getColStatus(int i) const;

     virtual VarStatus _getRowStatus(int i) const;

     virtual Value _getPrimalRay(int i) const;

     virtual Value _getDualRay(int i) const;

     ///\todo It should be clarified

     ///

     virtual ProblemType _getPrimalType() const;

     virtual ProblemType _getDualType() const;

   public:

     ///Solve with primal simplex

     SolveExitStatus solvePrimal();

     ///Solve with dual simplex

     SolveExitStatus solveDual();

     ///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);

     ///Enum for \c messageLevel() parameter

     enum MessageLevel {

       /// no output (default value)

       MESSAGE_NO_OUTPUT = 0,

       /// error messages only

       MESSAGE_ERROR_MESSAGE = 1,

       /// normal output

       MESSAGE_NORMAL_OUTPUT = 2,

       /// full output (includes informational messages)

       MESSAGE_FULL_OUTPUT = 3

     };

   private:

     MessageLevel _message_level;

   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.

     void messageLevel(MessageLevel m);

   };

   /// \brief Interface for the GLPK MIP solver

   ///

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

   ///\ingroup lp_group

   class MipGlpk : public GlpkBase, public MipSolver {

   public:

     ///\e

     MipGlpk();

     ///\e

     MipGlpk(const MipGlpk&);

   protected:

     virtual MipGlpk* _cloneSolver() const;

     virtual MipGlpk* _newSolver() const;

     virtual const char* _solverName() const;

     virtual ColTypes _getColType(int col) const;

     virtual void _setColType(int col, ColTypes col_type);

     virtual SolveExitStatus _solve();

     virtual ProblemType _getType() const;

     virtual Value _getSol(int i) const;

     virtual Value _getSolValue() const;

     ///Enum for \c messageLevel() parameter

     enum MessageLevel {

       /// no output (default value)

       MESSAGE_NO_OUTPUT = 0,

       /// error messages only

       MESSAGE_ERROR_MESSAGE = 1,

       /// normal output

       MESSAGE_NORMAL_OUTPUT = 2,

       /// full output (includes informational messages)

       MESSAGE_FULL_OUTPUT = 3

     };

   private:

     MessageLevel _message_level;

   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.

     void messageLevel(MessageLevel m);

   };

 } //END OF NAMESPACE LEMON

 #endif //LEMON_LP_GLPK_H