/* -*- C++ -*-

 *

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

 *

 * Copyright (C) 2003-2006

 * 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.

 *

 */

#include<iostream>

#include<lemon/lp_soplex.h>

#include <soplex/soplex.h>

///\file

///\brief Implementation of the LEMON-SOPLEX lp solver interface.

namespace lemon {

  LpSoplex::LpSoplex() : LpSolverBase() {

    soplex = new soplex::SoPlex;

  }

  LpSoplex::~LpSoplex() {

    delete soplex;

  }

  LpSolverBase &LpSoplex::_newLp() {

    LpSoplex* newlp = new LpSoplex();

    return *newlp;

  }

  LpSolverBase &LpSoplex::_copyLp() {

    LpSoplex* newlp = new LpSoplex();

    ((soplex::SPxLP&)*(newlp->soplex)) = *soplex;

    return *newlp;

  }

  int LpSoplex::_addCol() {

    soplex::LPCol col;

    soplex->addCol(col);

    colNames.push_back(std::string());

    primal.push_back(0.0);

    return soplex->nCols() - 1;

  }

  int LpSoplex::_addRow() {

    soplex::LPRow row;

    soplex->addRow(row);

    dual.push_back(0.0);

    return soplex->nRows() - 1;

  }

  void LpSoplex::_eraseCol(int i) {

    soplex->removeCol(i);

    primal[i] = primal.back();

    primal.pop_back();

  }

  void LpSoplex::_eraseRow(int i) {

    soplex->removeRow(i);

    dual[i] = dual.back();

    dual.pop_back();

  }

  void LpSoplex::_getColName(int col, std::string &name) {

    name = colNames[col]; 

  }

  void LpSoplex::_setColName(int col, const std::string &name) {

    colNames[col] = name; 

  }

  void LpSoplex::_setRowCoeffs(int i, LpRowIterator b, LpRowIterator e) {

    for (int j = 0; j < soplex->nCols(); ++j) {

      soplex->changeElement(i, j, 0.0);

    }

    for(LpRowIterator it = b; it != e; ++it) {

      soplex->changeElement(i, it->first, it->second);

    }

  }

  void LpSoplex::_setColCoeffs(int j, LpColIterator b, LpColIterator e) {

    for (int i = 0; i < soplex->nRows(); ++i) {

      soplex->changeElement(i, j, 0.0);

    }

    for(LpColIterator it = b; it != e; ++it) {

      soplex->changeElement(it->first, j, it->second);

    }

  }

  void LpSoplex::_setCoeff(int row, int col, Value value) {

    soplex->changeElement(row, col, value);

  }

  void LpSoplex::_setColLowerBound(int i, Value value) {

    soplex->changeLower(i, value); 

  }

  void LpSoplex::_setColUpperBound(int i, Value value) {

    soplex->changeUpper(i, value); 

  }

  void LpSoplex::_setRowBounds(int i, Value lb, Value ub) {

    soplex->changeRange(i, lb, ub);

  }

  void LpSoplex::_setObjCoeff(int i, Value obj_coef) {

    soplex->changeObj(i, obj_coef);

  }

  void LpSoplex::_clearObj() {

    for (int i = 0; i < soplex->nCols(); ++i) {

      soplex->changeObj(i, 0.0);

    }

  }

  LpSoplex::SolveExitStatus LpSoplex::_solve() {

    soplex::SPxSolver::Status status = soplex->solve();

    soplex::Vector pv(primal.size(), &primal[0]);

    soplex->getPrimal(pv);

    soplex::Vector dv(dual.size(), &dual[0]);

    soplex->getDual(dv);

    switch (status) {

    case soplex::SPxSolver::OPTIMAL:

    case soplex::SPxSolver::INFEASIBLE:

    case soplex::SPxSolver::UNBOUNDED:

      return SOLVED;

    default:

      return UNSOLVED;

    }

  }

  LpSoplex::Value LpSoplex::_getPrimal(int i) {

    return primal[i];

  }

  LpSoplex::Value LpSoplex::_getDual(int i) {

    return dual[i];

  }

  LpSoplex::Value LpSoplex::_getPrimalValue() {

    return soplex->objValue();

  }

  bool LpSoplex::_isBasicCol(int i) {

    return soplex->getBasisColStatus(i) == soplex::SPxSolver::BASIC;

  }  

  LpSoplex::SolutionStatus LpSoplex::_getPrimalStatus() {

    switch (soplex->status()) {

    case soplex::SPxSolver::OPTIMAL:

      return OPTIMAL;

    case soplex::SPxSolver::UNBOUNDED:

      return INFINITE;

    case soplex::SPxSolver::INFEASIBLE:

      return INFEASIBLE;

    default:

      return UNDEFINED;

    }

  }

  LpSoplex::SolutionStatus LpSoplex::_getDualStatus() {

    switch (0) {

    case 0:

      return UNDEFINED;

      return OPTIMAL;

      return INFEASIBLE;

      return UNDEFINED;

    }

  }

  LpSoplex::ProblemTypes LpSoplex::_getProblemType() {

    switch (0) {

    case 0:

      return PRIMAL_DUAL_FEASIBLE;

      return PRIMAL_FEASIBLE_DUAL_INFEASIBLE;

      return UNKNOWN;

    }

  }

  void LpSoplex::_setMax() {

    soplex->changeSense(soplex::SPxSolver::MAXIMIZE);

  }

  void LpSoplex::_setMin() {

    soplex->changeSense(soplex::SPxSolver::MINIMIZE);

  }

} //namespace lemon