//=====================================================
// Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
//=====================================================
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program 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 General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
//
#ifndef GMM_INTERFACE_HH
#define GMM_INTERFACE_HH

#include <gmm/gmm.h>
#include <vector>

using namespace gmm;

template <class real>
class gmm_interface {
 public:
  typedef real real_type;

  typedef std::vector<real> stl_vector;
  typedef std::vector<stl_vector> stl_matrix;

  typedef gmm::dense_matrix<real> gene_matrix;
  typedef stl_vector gene_vector;

  static inline std::string name(void) { return "gmm"; }

  static void free_matrix(gene_matrix& A, int N) { return; }

  static void free_vector(gene_vector& B) { return; }

  static inline void matrix_from_stl(gene_matrix& A, stl_matrix& A_stl) {
    A.resize(A_stl[0].size(), A_stl.size());

    for (int j = 0; j < A_stl.size(); j++) {
      for (int i = 0; i < A_stl[j].size(); i++) {
        A(i, j) = A_stl[j][i];
      }
    }
  }

  static inline void vector_from_stl(gene_vector& B, stl_vector& B_stl) { B = B_stl; }

  static inline void vector_to_stl(gene_vector& B, stl_vector& B_stl) { B_stl = B; }

  static inline void matrix_to_stl(gene_matrix& A, stl_matrix& A_stl) {
    int N = A_stl.size();

    for (int j = 0; j < N; j++) {
      A_stl[j].resize(N);
      for (int i = 0; i < N; i++) {
        A_stl[j][i] = A(i, j);
      }
    }
  }

  static inline void matrix_matrix_product(const gene_matrix& A, const gene_matrix& B, gene_matrix& X, int N) {
    gmm::mult(A, B, X);
  }

  static inline void transposed_matrix_matrix_product(const gene_matrix& A, const gene_matrix& B, gene_matrix& X,
                                                      int N) {
    gmm::mult(gmm::transposed(A), gmm::transposed(B), X);
  }

  static inline void ata_product(const gene_matrix& A, gene_matrix& X, int N) { gmm::mult(gmm::transposed(A), A, X); }

  static inline void aat_product(const gene_matrix& A, gene_matrix& X, int N) { gmm::mult(A, gmm::transposed(A), X); }

  static inline void matrix_vector_product(gene_matrix& A, gene_vector& B, gene_vector& X, int N) {
    gmm::mult(A, B, X);
  }

  static inline void atv_product(gene_matrix& A, gene_vector& B, gene_vector& X, int N) {
    gmm::mult(gmm::transposed(A), B, X);
  }

  static inline void axpy(const real coef, const gene_vector& X, gene_vector& Y, int N) {
    gmm::add(gmm::scaled(X, coef), Y);
  }

  static inline void axpby(real a, const gene_vector& X, real b, gene_vector& Y, int N) {
    gmm::add(gmm::scaled(X, a), gmm::scaled(Y, b), Y);
  }

  static inline void copy_matrix(const gene_matrix& source, gene_matrix& cible, int N) { gmm::copy(source, cible); }

  static inline void copy_vector(const gene_vector& source, gene_vector& cible, int N) { gmm::copy(source, cible); }

  static inline void trisolve_lower(const gene_matrix& L, const gene_vector& B, gene_vector& X, int N) {
    gmm::copy(B, X);
    gmm::lower_tri_solve(L, X, false);
  }

  static inline void partial_lu_decomp(const gene_matrix& X, gene_matrix& R, int N) {
    gmm::copy(X, R);
    std::vector<int> ipvt(N);
    gmm::lu_factor(R, ipvt);
  }

  static inline void hessenberg(const gene_matrix& X, gene_matrix& R, int N) {
    gmm::copy(X, R);
    gmm::Hessenberg_reduction(R, X, false);
  }

  static inline void tridiagonalization(const gene_matrix& X, gene_matrix& R, int N) {
    gmm::copy(X, R);
    gmm::Householder_tridiagonalization(R, X, false);
  }
};

#endif