/*

Copyright (C) 1994-2017 John W. Eaton

This file is part of Octave.

Octave 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.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <string>
#include <vector>

#include "Array-util.h"
#include "CMatrix.h"
#include "dMatrix.h"
#include "fCMatrix.h"
#include "fMatrix.h"
#include "gepbalance.h"
#include "lo-lapack-proto.h"
#include "oct-locbuf.h"

namespace octave
{
  namespace math
  {
    template <>
    octave_idx_type
    gepbalance<Matrix>::init (const Matrix& a, const Matrix& b,
                              const std::string& balance_job)
    {
      octave_idx_type n = a.cols ();

      if (a.rows () != n)
        (*current_liboctave_error_handler) ("GEPBALANCE requires square matrix");

      if (a.dims () != b.dims ())
        octave::err_nonconformant ("GEPBALANCE", n, n, b.rows(), b.cols());

      octave_idx_type info;
      octave_idx_type ilo;
      octave_idx_type ihi;

      OCTAVE_LOCAL_BUFFER (double, plscale, n);
      OCTAVE_LOCAL_BUFFER (double, prscale, n);
      OCTAVE_LOCAL_BUFFER (double, pwork, 6 * n);

      balanced_mat = a;
      double *p_balanced_mat = balanced_mat.fortran_vec ();
      balanced_mat2 = b;
      double *p_balanced_mat2 = balanced_mat2.fortran_vec ();

      char job = balance_job[0];

      F77_XFCN (dggbal, DGGBAL, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 n, p_balanced_mat, n, p_balanced_mat2,
                                 n, ilo, ihi, plscale, prscale, pwork, info
                                 F77_CHAR_ARG_LEN  (1)));

      balancing_mat = Matrix (n, n, 0.0);
      balancing_mat2 = Matrix (n, n, 0.0);
      for (octave_idx_type i = 0; i < n; i++)
        {
          octave_quit ();
          balancing_mat.elem (i ,i) = 1.0;
          balancing_mat2.elem (i ,i) = 1.0;
        }

      double *p_balancing_mat = balancing_mat.fortran_vec ();
      double *p_balancing_mat2 = balancing_mat2.fortran_vec ();

      // first left
      F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("L", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      // then right
      F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("R", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat2, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      return info;
    }

    template <>
    octave_idx_type
    gepbalance<FloatMatrix>::init (const FloatMatrix& a, const FloatMatrix& b,
                                   const std::string& balance_job)
    {
      octave_idx_type n = a.cols ();

      if (a.rows () != n)
        (*current_liboctave_error_handler)
          ("FloatGEPBALANCE requires square matrix");

      if (a.dims () != b.dims ())
        octave::err_nonconformant ("FloatGEPBALANCE", n, n, b.rows(), b.cols());

      octave_idx_type info;
      octave_idx_type ilo;
      octave_idx_type ihi;

      OCTAVE_LOCAL_BUFFER (float, plscale, n);
      OCTAVE_LOCAL_BUFFER (float, prscale, n);
      OCTAVE_LOCAL_BUFFER (float, pwork, 6 * n);

      balanced_mat = a;
      float *p_balanced_mat = balanced_mat.fortran_vec ();
      balanced_mat2 = b;
      float *p_balanced_mat2 = balanced_mat2.fortran_vec ();

      char job = balance_job[0];

      F77_XFCN (sggbal, SGGBAL, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 n, p_balanced_mat, n, p_balanced_mat2,
                                 n, ilo, ihi, plscale, prscale, pwork, info
                                 F77_CHAR_ARG_LEN  (1)));

      balancing_mat = FloatMatrix (n, n, 0.0);
      balancing_mat2 = FloatMatrix (n, n, 0.0);
      for (octave_idx_type i = 0; i < n; i++)
        {
          octave_quit ();
          balancing_mat.elem (i ,i) = 1.0;
          balancing_mat2.elem (i ,i) = 1.0;
        }

      float *p_balancing_mat = balancing_mat.fortran_vec ();
      float *p_balancing_mat2 = balancing_mat2.fortran_vec ();

      // first left
      F77_XFCN (sggbak, SGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("L", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      // then right
      F77_XFCN (sggbak, SGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("R", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat2, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      return info;
    }

    template <>
    octave_idx_type
    gepbalance<ComplexMatrix>::init (const ComplexMatrix& a,
                                     const ComplexMatrix& b,
                                     const std::string& balance_job)
    {
      octave_idx_type n = a.cols ();

      if (a.rows () != n)
        (*current_liboctave_error_handler)
          ("ComplexGEPBALANCE requires square matrix");

      if (a.dims () != b.dims ())
        octave::err_nonconformant ("ComplexGEPBALANCE", n, n, b.rows(), b.cols());

      octave_idx_type info;
      octave_idx_type ilo;
      octave_idx_type ihi;

      OCTAVE_LOCAL_BUFFER (double, plscale, n);
      OCTAVE_LOCAL_BUFFER (double, prscale,  n);
      OCTAVE_LOCAL_BUFFER (double, pwork, 6 * n);

      balanced_mat = a;
      Complex *p_balanced_mat = balanced_mat.fortran_vec ();
      balanced_mat2 = b;
      Complex *p_balanced_mat2 = balanced_mat2.fortran_vec ();

      char job = balance_job[0];

      F77_XFCN (zggbal, ZGGBAL, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 n, F77_DBLE_CMPLX_ARG (p_balanced_mat), n, F77_DBLE_CMPLX_ARG (p_balanced_mat2),
                                 n, ilo, ihi, plscale, prscale, pwork, info
                                 F77_CHAR_ARG_LEN (1)));

      balancing_mat = Matrix (n, n, 0.0);
      balancing_mat2 = Matrix (n, n, 0.0);
      for (octave_idx_type i = 0; i < n; i++)
        {
          octave_quit ();
          balancing_mat.elem (i ,i) = 1.0;
          balancing_mat2.elem (i ,i) = 1.0;
        }

      double *p_balancing_mat = balancing_mat.fortran_vec ();
      double *p_balancing_mat2 = balancing_mat2.fortran_vec ();

      // first left
      F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("L", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      // then right
      F77_XFCN (dggbak, DGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("R", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat2, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      return info;
    }

    template <>
    octave_idx_type
    gepbalance<FloatComplexMatrix>::init (const FloatComplexMatrix& a,
                                          const FloatComplexMatrix& b,
                                          const std::string& balance_job)
    {
      octave_idx_type n = a.cols ();

      if (a.rows () != n)
        {
          (*current_liboctave_error_handler)
            ("FloatComplexGEPBALANCE requires square matrix");
          return -1;
        }

      if (a.dims () != b.dims ())
        octave::err_nonconformant ("FloatComplexGEPBALANCE", n, n, b.rows(), b.cols());

      octave_idx_type info;
      octave_idx_type ilo;
      octave_idx_type ihi;

      OCTAVE_LOCAL_BUFFER (float, plscale, n);
      OCTAVE_LOCAL_BUFFER (float, prscale, n);
      OCTAVE_LOCAL_BUFFER (float, pwork, 6 * n);

      balanced_mat = a;
      FloatComplex *p_balanced_mat = balanced_mat.fortran_vec ();
      balanced_mat2 = b;
      FloatComplex *p_balanced_mat2 = balanced_mat2.fortran_vec ();

      char job = balance_job[0];

      F77_XFCN (cggbal, CGGBAL, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 n, F77_CMPLX_ARG (p_balanced_mat), n, F77_CMPLX_ARG (p_balanced_mat2),
                                 n, ilo, ihi, plscale, prscale, pwork, info
                                 F77_CHAR_ARG_LEN (1)));

      balancing_mat = FloatMatrix (n, n, 0.0);
      balancing_mat2 = FloatMatrix (n, n, 0.0);
      for (octave_idx_type i = 0; i < n; i++)
        {
          octave_quit ();
          balancing_mat.elem (i ,i) = 1.0;
          balancing_mat2.elem (i ,i) = 1.0;
        }

      float *p_balancing_mat = balancing_mat.fortran_vec ();
      float *p_balancing_mat2 = balancing_mat2.fortran_vec ();

      // first left
      F77_XFCN (sggbak, SGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("L", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      // then right
      F77_XFCN (sggbak, SGGBAK, (F77_CONST_CHAR_ARG2 (&job, 1),
                                 F77_CONST_CHAR_ARG2 ("R", 1),
                                 n, ilo, ihi, plscale, prscale,
                                 n, p_balancing_mat2, n, info
                                 F77_CHAR_ARG_LEN (1)
                                 F77_CHAR_ARG_LEN (1)));

      return info;
    }

    // Instantiations we need.

    template class gepbalance<Matrix>;

    template class gepbalance<FloatMatrix>;

    template class gepbalance<ComplexMatrix>;

    template class gepbalance<FloatComplexMatrix>;
  }
}