/*
 Copyright (C) 2014 Eugenio Gianniti <eugenio.gianniti@mail.polimi.it>

 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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "uBLAS_factory.h"

femfenics_base_factory const&
uBLAS_factory::instance (void)
  {
    static uBLAS_factory const theinstance;
    return theinstance;
  }

octave_value
uBLAS_factory::matrix (dolfin::Matrix const& A) const
  {
    octave_value retval;

    // Get capacity of the dolfin sparse matrix
    boost::tuples::tuple<const std::size_t*, 
                         const std::size_t*, 
                         const double*, int> 
      aa = A.data ();

    int nnz = aa.get<3> ();
    std::size_t nr = A.size (0), nc = A.size (1);
    std::vector<double> data_tmp;
    std::vector<std::size_t> cidx_tmp;

    dim_vector dims (nnz, 1);
    octave_idx_type nz = 0, ii = 0;
    Array<octave_idx_type> 
      ridx (dims, 0), 
      cidx (dims, 0);
    Array<double> data (dims, 0);

    octave_idx_type* orow = ridx.fortran_vec ();
    octave_idx_type* oc = cidx.fortran_vec ();
    double* ov = data.fortran_vec ();

    for (std::size_t i = 0; i < nr; ++i)
      {
        A.getrow (i, cidx_tmp, data_tmp);
        nz += cidx_tmp.size ();

        for (octave_idx_type j = 0; 
             j < cidx_tmp.size (); ++j)
          {
            orow [ii + j] = i;
            oc [ii + j] = cidx_tmp [j];
            ov [ii + j] = data_tmp [j];
          }

        ii = nz;
      }

    dims(0) = ii;
    ridx.resize (dims);
    cidx.resize (dims);
    data.resize (dims);

    SparseMatrix sm (data, ridx, cidx, nr, nc);
    retval = sm;

    return retval;
  }

octave_value
uBLAS_factory::vector (dolfin::Vector const& b) const
  {
    octave_value retval;

    dim_vector dims;
    dims.resize (2);
    dims(0) = b.size ();
    dims(1) = 1;
    Array<double> myb (dims);

    for (std::size_t i = 0; i < b.size (); ++i)
      myb.xelem (i) = b[i];

    retval = myb;

    return retval;
  }