/***************************************************************************
 *   Copyright (c) Konstantinos Poulios      (logari81@gmail.com) 2011     *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Library General Public           *
 *   License as published by the Free Software Foundation; either          *
 *   version 2 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 Library General Public License for more details.                  *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this library; see the file COPYING.LIB. If not,    *
 *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
 *   Suite 330, Boston, MA  02111-1307, USA                                *
 *                                                                         *
 ***************************************************************************/

#ifndef FREEGCS_SUBSYSTEM_H
#define FREEGCS_SUBSYSTEM_H

#undef min
#undef max

#include <Eigen/Dense>
#include "Constraints.h"

namespace GCS
{

    class SubSystem
    {
    private:
        int psize, csize;
        std::vector<Constraint *> clist;
        VEC_pD plist;      // pointers to the original parameters
        MAP_pD_pD pmap;    // redirection map from the original parameters to pvals
        VEC_D pvals;       // current variables vector (psize)
//        JacobianMatrix jacobi;  // jacobi matrix of the residuals
        std::map<Constraint *,VEC_pD > c2p; // constraint to parameter adjacency list
        std::map<double *,std::vector<Constraint *> > p2c; // parameter to constraint adjacency list
        void initialize(VEC_pD &params, MAP_pD_pD &reductionmap); // called by the constructors
    public:
        SubSystem(std::vector<Constraint *> &clist_, VEC_pD &params);
        SubSystem(std::vector<Constraint *> &clist_, VEC_pD &params,
                  MAP_pD_pD &reductionmap);
        ~SubSystem();

        int pSize() { return psize; };
        int cSize() { return csize; };

        void redirectParams();
        void revertParams();

        void getParamMap(MAP_pD_pD &pmapOut);
        void getParamList(VEC_pD &plistOut);

        void getParams(VEC_pD &params, Eigen::VectorXd &xOut);
        void getParams(Eigen::VectorXd &xOut);
        void setParams(VEC_pD &params, Eigen::VectorXd &xIn);
        void setParams(Eigen::VectorXd &xIn);

        double error();
        void calcResidual(Eigen::VectorXd &r);
        void calcResidual(Eigen::VectorXd &r, double &err);
        void calcJacobi(VEC_pD &params, Eigen::MatrixXd &jacobi);
        void calcJacobi(Eigen::MatrixXd &jacobi);
        void calcGrad(VEC_pD &params, Eigen::VectorXd &grad);
        void calcGrad(Eigen::VectorXd &grad);

        double maxStep(VEC_pD &params, Eigen::VectorXd &xdir);
        double maxStep(Eigen::VectorXd &xdir);

        void applySolution();
        void analyse(Eigen::MatrixXd &J, Eigen::MatrixXd &ker, Eigen::MatrixXd &img);
        void report();

void printResidual();
    };

    double lineSearch(SubSystem *subsys, Eigen::VectorXd &xdir);

} //namespace GCS

#endif // FREEGCS_SUBSYSTEM_H