#include <petsc/private/fortranimpl.h>
#include <petscmat.h>

#if defined(PETSC_HAVE_FORTRAN_CAPS)
#define matshellsetoperation_            MATSHELLSETOPERATION
#define matcreateshell_                  MATCREATESHELL
#elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
#define matcreateshell_                  matcreateshell
#define matshellsetoperation_            matshellsetoperation
#endif

/**
 * Subset of MatOperation that is supported by the Fortran wrappers.
 */
enum FortranMatOperation {
  FORTRAN_MATOP_MULT = 0,
  FORTRAN_MATOP_MULT_ADD = 1,
  FORTRAN_MATOP_MULT_TRANSPOSE = 2,
  FORTRAN_MATOP_MULT_TRANSPOSE_ADD = 3,
  FORTRAN_MATOP_SOR = 4,
  FORTRAN_MATOP_TRANSPOSE = 5,
  FORTRAN_MATOP_GET_DIAGONAL = 6,
  FORTRAN_MATOP_DIAGONAL_SCALE = 7,
  FORTRAN_MATOP_ZERO_ENTRIES = 8,
  FORTRAN_MATOP_AXPY = 9,
  FORTRAN_MATOP_SHIFT = 10,
  FORTRAN_MATOP_DIAGONAL_SET = 11,
  FORTRAN_MATOP_DESTROY = 12,
  FORTRAN_MATOP_VIEW = 13,
  FORTRAN_MATOP_GET_VECS = 14,
  FORTRAN_MATOP_GET_DIAGONAL_BLOCK = 15,
  FORTRAN_MATOP_SIZE = 16
};

/*
  The MatShell Matrix Vector product requires a C routine.
  This C routine then calls the corresponding Fortran routine that was
  set by the user.
*/
PETSC_EXTERN void PETSC_STDCALL matcreateshell_(MPI_Comm *comm, PetscInt *m, PetscInt *n, PetscInt *M, PetscInt *N, void *ctx, Mat *mat, PetscErrorCode *ierr)
{
  *ierr = MatCreateShell(MPI_Comm_f2c(*(MPI_Fint*)&*comm), *m, *n, *M, *N, ctx, mat);
}

static PetscErrorCode ourmult(Mat mat, Vec x, Vec y)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_MULT]))(&mat, &x, &y, &ierr);
  return ierr;
}

static PetscErrorCode ourmultadd(Mat mat, Vec x, Vec y, Vec z)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_ADD]))(&mat, &x, &y, &z, &ierr);
  return ierr;
}

static PetscErrorCode ourmulttranspose(Mat mat, Vec x, Vec y)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_TRANSPOSE]))(&mat, &x, &y, &ierr);
  return ierr;
}

static PetscErrorCode ourmulttransposeadd(Mat mat, Vec x, Vec y, Vec z)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_TRANSPOSE_ADD]))(&mat, &x, &y, &z, &ierr);
  return ierr;
}

static PetscErrorCode oursor(Mat mat, Vec b, PetscReal omega, MatSORType flg, PetscReal shift, PetscInt its, PetscInt lits, Vec x)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, PetscReal*, MatSORType*, PetscReal*, PetscInt*, PetscInt*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_SOR]))(&mat, &b, &omega, &flg, &shift, &its, &lits, &x, &ierr);
  return ierr;
}

static PetscErrorCode ourtranspose(Mat mat, MatReuse reuse, Mat *B)
{
  PetscErrorCode ierr = 0;
  Mat *b = (!B ? (Mat *) PETSC_NULL_OBJECT_Fortran : B);

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, MatReuse*, Mat *, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_TRANSPOSE]))(&mat, &reuse, b, &ierr);
  return ierr;
}

static PetscErrorCode ourgetdiagonal(Mat mat, Vec x)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_GET_DIAGONAL]))(&mat, &x, &ierr);
  return ierr;
}

static PetscErrorCode ourdiagonalscale(Mat mat, Vec l, Vec r)
{
  PetscErrorCode ierr = 0;
  Vec *a = (!l ? (Vec*) PETSC_NULL_OBJECT_Fortran : &l);
  Vec *b = (!r ? (Vec*) PETSC_NULL_OBJECT_Fortran : &r);

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_DIAGONAL_SCALE]))(&mat, a, b, &ierr);
  return ierr;
}

static PetscErrorCode ourzeroentries(Mat mat)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_ZERO_ENTRIES]))(&mat, &ierr);
  return ierr;
}

static PetscErrorCode ouraxpy(Mat mat, PetscScalar a, Mat X, MatStructure str)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, PetscScalar*, Mat*, MatStructure*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_AXPY]))(&mat, &a, &X, &str, &ierr);
  return ierr;
}

static PetscErrorCode ourshift(Mat mat, PetscScalar a)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, PetscScalar*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_SHIFT]))(&mat, &a, &ierr);
  return ierr;
}

static PetscErrorCode ourdiagonalset(Mat mat, Vec x, InsertMode ins)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, InsertMode*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_DIAGONAL_SET]))(&mat, &x, &ins, &ierr);
  return ierr;
}

static PetscErrorCode ourdestroy(Mat mat)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_DESTROY]))(&mat, &ierr);
  return ierr;
}

static PetscErrorCode ourview(Mat mat, PetscViewer v)
{
  PetscErrorCode ierr = 0;

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, PetscViewer*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_VIEW]))(&mat, &v, &ierr);
  return ierr;
}

static PetscErrorCode ourgetvecs(Mat mat, Vec *l, Vec *r)
{
  PetscErrorCode ierr = 0;
  Vec *a = (!l ? (Vec *) PETSC_NULL_OBJECT_Fortran : l);
  Vec *b = (!r ? (Vec *) PETSC_NULL_OBJECT_Fortran : r);

  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Vec*, Vec*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_GET_VECS]))(&mat, a, b, &ierr);
  return ierr;
}

static PetscErrorCode ourgetdiagonalblock(Mat mat, Mat *l)
{
  PetscErrorCode ierr = 0;
  (*(PetscErrorCode (PETSC_STDCALL *)(Mat*, Mat*, PetscErrorCode*))(((PetscObject) mat)->fortran_func_pointers[FORTRAN_MATOP_GET_DIAGONAL_BLOCK]))(&mat, l, &ierr);
  return ierr;
}

PETSC_EXTERN void PETSC_STDCALL matshellsetoperation_(Mat *mat, MatOperation *op, PetscErrorCode (PETSC_STDCALL *f)(Mat*, Vec*, Vec*, PetscErrorCode*), PetscErrorCode *ierr)
{
  MPI_Comm comm;

  *ierr = PetscObjectGetComm((PetscObject) *mat, &comm);if (*ierr) return;
  PetscObjectAllocateFortranPointers(*mat, FORTRAN_MATOP_SIZE);

  switch (*op) {
  case MATOP_MULT:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourmult);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_MULT] = (PetscVoidFunction) f;
    break;
  case MATOP_MULT_ADD:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourmultadd);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_ADD] = (PetscVoidFunction) f;
    break;
  case MATOP_MULT_TRANSPOSE:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourmulttranspose);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_TRANSPOSE] = (PetscVoidFunction) f;
    break;
  case MATOP_MULT_TRANSPOSE_ADD:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourmulttransposeadd);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_MULT_TRANSPOSE_ADD] = (PetscVoidFunction) f;
    break;
  case MATOP_SOR:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) oursor);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_SOR] = (PetscVoidFunction) f;
    break;
  case MATOP_TRANSPOSE:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourtranspose);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_TRANSPOSE] = (PetscVoidFunction) f;
    break;
  case MATOP_GET_DIAGONAL:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourgetdiagonal);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_GET_DIAGONAL] = (PetscVoidFunction) f;
    break;
  case MATOP_DIAGONAL_SCALE:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourdiagonalscale);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_DIAGONAL_SCALE] = (PetscVoidFunction) f;
    break;
  case MATOP_ZERO_ENTRIES:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourzeroentries);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_ZERO_ENTRIES] = (PetscVoidFunction) f;
    break;
  case MATOP_AXPY:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ouraxpy);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_AXPY] = (PetscVoidFunction) f;
    break;
  case MATOP_SHIFT:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourshift);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_SHIFT] = (PetscVoidFunction) f;
    break;
  case MATOP_DIAGONAL_SET:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourdiagonalset);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_DIAGONAL_SET] = (PetscVoidFunction) f;
    break;
  case MATOP_DESTROY:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourdestroy);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_DESTROY] = (PetscVoidFunction) f;
    break;
  case MATOP_VIEW:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourview);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_VIEW] = (PetscVoidFunction) f;
    break;
  case MATOP_GET_VECS:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourgetvecs);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_GET_VECS] = (PetscVoidFunction) f;
    break;
  case MATOP_GET_DIAGONAL_BLOCK:
    *ierr = MatShellSetOperation(*mat, *op, (PetscVoidFunction) ourgetdiagonalblock);
    ((PetscObject)*mat)->fortran_func_pointers[FORTRAN_MATOP_GET_DIAGONAL_BLOCK] = (PetscVoidFunction) f;
    break;
  default:
    PetscError(comm, __LINE__, "MatShellSetOperation_Fortran", __FILE__, PETSC_ERR_ARG_WRONG, PETSC_ERROR_INITIAL, "Cannot set that matrix operation");
    *ierr = 1;
  }
}