// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
// vi: set et ts=4 sw=4 sts=4:
/*
  This file is part of the Open Porous Media project (OPM).

  OPM 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.

  OPM 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 OPM.  If not, see <http://www.gnu.org/licenses/>.

  Consult the COPYING file in the top-level source directory of this
  module for the precise wording of the license and the list of
  copyright holders.
*/
#ifndef EWOMS_MATRIX_BLOCK_HH
#define EWOMS_MATRIX_BLOCK_HH

#include <dune/common/dynmatrix.hh>
#include <dune/common/fmatrix.hh>
#include <dune/common/typetraits.hh>

#include <dune/istl/superlu.hh>
#include <dune/istl/umfpack.hh>
#include <dune/istl/matrixutils.hh>

#include <opm/common/Exceptions.hpp>

#include <limits>

namespace Opm {
namespace detail {

template <typename K, int m, int n>
static inline void invertMatrix(Dune::FieldMatrix<K,m,n>& matrix)
{
    matrix.invert();
}

template <typename K>
static inline void invertMatrix(Dune::FieldMatrix<K,1,1>& matrix)
{
    Dune::FieldMatrix<K,1,1> tmp(matrix);
    Dune::FMatrixHelp::invertMatrix(tmp,matrix);
}

template <typename K>
static inline void invertMatrix(Dune::FieldMatrix<K,2,2>& matrix)
{
    Dune::FieldMatrix<K,2,2> tmp(matrix);
    Dune::FMatrixHelp::invertMatrix(tmp,matrix);
}

template <typename K>
static inline void invertMatrix(Dune::FieldMatrix<K,3,3>& matrix)
{
    Dune::FieldMatrix<K,3,3> tmp(matrix);
    Dune::FMatrixHelp::invertMatrix(tmp,matrix);
}

//! invert 4x4 Matrix without changing the original matrix
template <template<class K> class Matrix, typename K>
static inline K invertMatrix4(const Matrix<K>& matrix, Matrix<K>& inverse)
{
    inverse[0][0] = matrix[1][1] * matrix[2][2] * matrix[3][3] -
            matrix[1][1] * matrix[2][3] * matrix[3][2] -
            matrix[2][1] * matrix[1][2] * matrix[3][3] +
            matrix[2][1] * matrix[1][3] * matrix[3][2] +
            matrix[3][1] * matrix[1][2] * matrix[2][3] -
            matrix[3][1] * matrix[1][3] * matrix[2][2];

    inverse[1][0] = -matrix[1][0] * matrix[2][2] * matrix[3][3] +
            matrix[1][0] * matrix[2][3] * matrix[3][2] +
            matrix[2][0] * matrix[1][2] * matrix[3][3] -
            matrix[2][0] * matrix[1][3] * matrix[3][2] -
            matrix[3][0] * matrix[1][2] * matrix[2][3] +
            matrix[3][0] * matrix[1][3] * matrix[2][2];

    inverse[2][0] = matrix[1][0] * matrix[2][1] * matrix[3][3] -
            matrix[1][0] * matrix[2][3] * matrix[3][1] -
            matrix[2][0] * matrix[1][1] * matrix[3][3] +
            matrix[2][0] * matrix[1][3] * matrix[3][1] +
            matrix[3][0] * matrix[1][1] * matrix[2][3] -
            matrix[3][0] * matrix[1][3] * matrix[2][1];

    inverse[3][0] = -matrix[1][0] * matrix[2][1] * matrix[3][2] +
            matrix[1][0] * matrix[2][2] * matrix[3][1] +
            matrix[2][0] * matrix[1][1] * matrix[3][2] -
            matrix[2][0] * matrix[1][2] * matrix[3][1] -
            matrix[3][0] * matrix[1][1] * matrix[2][2] +
            matrix[3][0] * matrix[1][2] * matrix[2][1];

    inverse[0][1]= -matrix[0][1]  * matrix[2][2] * matrix[3][3] +
            matrix[0][1] * matrix[2][3] * matrix[3][2] +
            matrix[2][1] * matrix[0][2] * matrix[3][3] -
            matrix[2][1] * matrix[0][3] * matrix[3][2] -
            matrix[3][1] * matrix[0][2] * matrix[2][3] +
            matrix[3][1] * matrix[0][3] * matrix[2][2];

    inverse[1][1] = matrix[0][0] * matrix[2][2] * matrix[3][3] -
            matrix[0][0] * matrix[2][3] * matrix[3][2] -
            matrix[2][0] * matrix[0][2] * matrix[3][3] +
            matrix[2][0] * matrix[0][3] * matrix[3][2] +
            matrix[3][0] * matrix[0][2] * matrix[2][3] -
            matrix[3][0] * matrix[0][3] * matrix[2][2];

    inverse[2][1] = -matrix[0][0] * matrix[2][1] * matrix[3][3] +
            matrix[0][0] * matrix[2][3] * matrix[3][1] +
            matrix[2][0] * matrix[0][1] * matrix[3][3] -
            matrix[2][0] * matrix[0][3] * matrix[3][1] -
            matrix[3][0] * matrix[0][1] * matrix[2][3] +
            matrix[3][0] * matrix[0][3] * matrix[2][1];

    inverse[3][1] = matrix[0][0] * matrix[2][1] * matrix[3][2] -
            matrix[0][0] * matrix[2][2] * matrix[3][1] -
            matrix[2][0] * matrix[0][1] * matrix[3][2] +
            matrix[2][0] * matrix[0][2] * matrix[3][1] +
            matrix[3][0] * matrix[0][1] * matrix[2][2] -
            matrix[3][0] * matrix[0][2] * matrix[2][1];

    inverse[0][2] = matrix[0][1] * matrix[1][2] * matrix[3][3] -
            matrix[0][1] * matrix[1][3] * matrix[3][2] -
            matrix[1][1] * matrix[0][2] * matrix[3][3] +
            matrix[1][1] * matrix[0][3] * matrix[3][2] +
            matrix[3][1] * matrix[0][2] * matrix[1][3] -
            matrix[3][1] * matrix[0][3] * matrix[1][2];

    inverse[1][2] = -matrix[0][0]  * matrix[1][2] * matrix[3][3] +
            matrix[0][0] * matrix[1][3] * matrix[3][2] +
            matrix[1][0] * matrix[0][2] * matrix[3][3] -
            matrix[1][0] * matrix[0][3] * matrix[3][2] -
            matrix[3][0] * matrix[0][2] * matrix[1][3] +
            matrix[3][0] * matrix[0][3] * matrix[1][2];

    inverse[2][2] = matrix[0][0] * matrix[1][1] * matrix[3][3] -
            matrix[0][0] * matrix[1][3] * matrix[3][1] -
            matrix[1][0] * matrix[0][1] * matrix[3][3] +
            matrix[1][0] * matrix[0][3] * matrix[3][1] +
            matrix[3][0] * matrix[0][1] * matrix[1][3] -
            matrix[3][0] * matrix[0][3] * matrix[1][1];

    inverse[3][2] = -matrix[0][0] * matrix[1][1] * matrix[3][2] +
            matrix[0][0] * matrix[1][2] * matrix[3][1] +
            matrix[1][0] * matrix[0][1] * matrix[3][2] -
            matrix[1][0] * matrix[0][2] * matrix[3][1] -
            matrix[3][0] * matrix[0][1] * matrix[1][2] +
            matrix[3][0] * matrix[0][2] * matrix[1][1];

    inverse[0][3] = -matrix[0][1] * matrix[1][2] * matrix[2][3] +
            matrix[0][1] * matrix[1][3] * matrix[2][2] +
            matrix[1][1] * matrix[0][2] * matrix[2][3] -
            matrix[1][1] * matrix[0][3] * matrix[2][2] -
            matrix[2][1] * matrix[0][2] * matrix[1][3] +
            matrix[2][1] * matrix[0][3] * matrix[1][2];

    inverse[1][3] = matrix[0][0] * matrix[1][2] * matrix[2][3] -
            matrix[0][0] * matrix[1][3] * matrix[2][2] -
            matrix[1][0] * matrix[0][2] * matrix[2][3] +
            matrix[1][0] * matrix[0][3] * matrix[2][2] +
            matrix[2][0] * matrix[0][2] * matrix[1][3] -
            matrix[2][0] * matrix[0][3] * matrix[1][2];

    inverse[2][3] = -matrix[0][0] * matrix[1][1] * matrix[2][3] +
            matrix[0][0] * matrix[1][3] * matrix[2][1] +
            matrix[1][0] * matrix[0][1] * matrix[2][3] -
            matrix[1][0] * matrix[0][3] * matrix[2][1] -
            matrix[2][0] * matrix[0][1] * matrix[1][3] +
            matrix[2][0] * matrix[0][3] * matrix[1][1];

    inverse[3][3] = matrix[0][0] * matrix[1][1] * matrix[2][2] -
            matrix[0][0] * matrix[1][2] * matrix[2][1] -
            matrix[1][0] * matrix[0][1] * matrix[2][2] +
            matrix[1][0] * matrix[0][2] * matrix[2][1] +
            matrix[2][0] * matrix[0][1] * matrix[1][2] -
            matrix[2][0] * matrix[0][2] * matrix[1][1];

    K det = matrix[0][0] * inverse[0][0] + matrix[0][1] * inverse[1][0] +
            matrix[0][2] * inverse[2][0] + matrix[0][3] * inverse[3][0];

    // return identity for singular or nearly singular matrices.
    if (std::abs(det) < 1e-40) {
        inverse = std::numeric_limits<K>::quiet_NaN();
        throw NumericalProblem("Singular matrix");
    } else
      inverse *= 1.0 / det;

    return det;
}

template<class K> using FMat4 = Dune::FieldMatrix<K,4,4>;

template <typename K>
static inline void invertMatrix(Dune::FieldMatrix<K,4,4>& matrix)
{
    FMat4<K> tmp(matrix);
    invertMatrix4<FMat4>(tmp, matrix);
}

template <typename K>
static inline void invertMatrix(Dune::DynamicMatrix<K>& matrix)
{
    // this function is only for 4 X 4 matrix
    // for 4 X 4 matrix, using the invertMatrix() function above
    // it is for temporary usage, mainly to reduce the huge burden of testing
    // what algorithm should be used to invert 4 X 4 matrix will be handled
    // as a seperate issue
    if (matrix.rows() == 4) {
         Dune::DynamicMatrix<K> A = matrix;
         invertMatrix4(A, matrix);
         return;
     }

     matrix.invert();
}

} // namespace detail

template <class Scalar, int n, int m>
class MatrixBlock : public Dune::FieldMatrix<Scalar, n, m>
{
public:
    using BaseType = Dune::FieldMatrix<Scalar, n, m> ;

    using BaseType::operator= ;
    using BaseType::rows;
    using BaseType::cols;

    MatrixBlock()
        : BaseType(Scalar(0.0))
    {}

    explicit MatrixBlock(const Scalar value)
        : BaseType(value)
    {}

    void invert()
    { detail::invertMatrix(asBase()); }

    const BaseType& asBase() const
    { return static_cast<const BaseType&>(*this); }

    BaseType& asBase()
    { return static_cast<BaseType&>(*this); }
};

} // namespace Opm

namespace Dune {

template<class K, int n, int m>
void print_row(std::ostream& s, const Opm::MatrixBlock<K, n, m>& A,
               typename FieldMatrix<K, n, m>::size_type I,
               typename FieldMatrix<K, n, m>::size_type J,
               typename FieldMatrix<K, n, m>::size_type therow,
               int width,
               int precision)
{ print_row(s, A.asBase(), I, J, therow, width, precision); }

template <typename Scalar, int n, int m>
struct MatrixDimension<Opm::MatrixBlock<Scalar, n, m> >
    : public MatrixDimension<typename Opm::MatrixBlock<Scalar, n, m>::BaseType>
{ };


#if HAVE_UMFPACK
/// \brief UMFPack specialization for Opm::MatrixBlock to make AMG happy
///
/// Without this the empty default implementation would be used.
template <typename T, typename A, int n, int m>
class UMFPack<BCRSMatrix<Opm::MatrixBlock<T, n, m>, A> >
    : public UMFPack<BCRSMatrix<FieldMatrix<T, n, m>, A> >
{
    using Base = UMFPack<BCRSMatrix<FieldMatrix<T, n, m>, A> >;
    using Matrix = BCRSMatrix<FieldMatrix<T, n, m>, A>;

public:
    using RealMatrix = BCRSMatrix<Opm::MatrixBlock<T, n, m>, A>;

    UMFPack(const RealMatrix& matrix, int verbose, bool)
        : Base(reinterpret_cast<const Matrix&>(matrix), verbose)
    {}
};
#endif

#if HAVE_SUPERLU
/// \brief SuperLU specialization for Opm::MatrixBlock to make AMG happy
///
/// Without this the empty default implementation would be used.
template <typename T, typename A, int n, int m>
class SuperLU<BCRSMatrix<Opm::MatrixBlock<T, n, m>, A> >
    : public SuperLU<BCRSMatrix<FieldMatrix<T, n, m>, A> >
{
    using Base = SuperLU<BCRSMatrix<FieldMatrix<T, n, m>, A> >;
    using Matrix = BCRSMatrix<FieldMatrix<T, n, m>, A>;

public:
    using RealMatrix = BCRSMatrix<Opm::MatrixBlock<T, n, m>, A>;

    SuperLU(const RealMatrix& matrix, int verb, bool reuse=true)
        : Base(reinterpret_cast<const Matrix&>(matrix), verb, reuse)
    {}
};
#endif

template<typename T, int n, int m>
struct IsNumber<Opm::MatrixBlock<T, n, m>>
    : public IsNumber<Dune::FieldMatrix<T,n,m>>
{};

} // end namespace Dune


#endif
