/*
      Objects which encapsulate finite volume spaces and operations
*/
#if !defined(__PETSCFV_H)
#define __PETSCFV_H
#include <petscdm.h>
#include <petscdt.h>
#include <petscfvtypes.h>

PETSC_EXTERN PetscErrorCode PetscFVInitializePackage(void);

PETSC_EXTERN PetscClassId PETSCFV_CLASSID;

/*J
  PetscFVType - String with the name of a PETSc finite volume discretization

  Level: beginner

.seealso: PetscFVSetType(), PetscFV
J*/
typedef const char *PetscFVType;
#define PETSCFVUPWIND       "upwind"
#define PETSCFVLEASTSQUARES "leastsquares"

PETSC_EXTERN PetscFunctionList PetscFVList;
PETSC_EXTERN PetscBool         PetscFVRegisterAllCalled;
PETSC_EXTERN PetscErrorCode PetscFVCreate(MPI_Comm, PetscFV *);
PETSC_EXTERN PetscErrorCode PetscFVDestroy(PetscFV *);
PETSC_EXTERN PetscErrorCode PetscFVSetType(PetscFV, PetscFVType);
PETSC_EXTERN PetscErrorCode PetscFVGetType(PetscFV, PetscFVType *);
PETSC_EXTERN PetscErrorCode PetscFVSetUp(PetscFV);
PETSC_EXTERN PetscErrorCode PetscFVSetFromOptions(PetscFV);
PETSC_EXTERN PetscErrorCode PetscFVViewFromOptions(PetscFV, const char[], const char[]);
PETSC_EXTERN PetscErrorCode PetscFVView(PetscFV, PetscViewer);
PETSC_EXTERN PetscErrorCode PetscFVRegister(const char [], PetscErrorCode (*)(PetscFV));
PETSC_EXTERN PetscErrorCode PetscFVRegisterAll(void);
PETSC_EXTERN PetscErrorCode PetscFVRegisterDestroy(void);

PETSC_EXTERN PetscErrorCode PetscFVSetNumComponents(PetscFV, PetscInt);
PETSC_EXTERN PetscErrorCode PetscFVGetNumComponents(PetscFV, PetscInt *);
PETSC_EXTERN PetscErrorCode PetscFVSetSpatialDimension(PetscFV, PetscInt);
PETSC_EXTERN PetscErrorCode PetscFVGetSpatialDimension(PetscFV, PetscInt *);

PETSC_EXTERN PetscErrorCode PetscFVIntegrateRHSFunction(PetscFV, PetscInt, PetscInt, PetscFV[], PetscInt, PetscCellGeometry, PetscCellGeometry, PetscScalar[], PetscScalar[],
                                                        void (*)(const PetscReal[], const PetscReal[], const PetscScalar[], const PetscScalar[], PetscScalar[], void *),
                                                        PetscScalar[], PetscScalar[], void *);

/* Assuming dim == 3 */
typedef struct {
  PetscScalar normal[3];   /* Area-scaled normals */
  PetscScalar centroid[3]; /* Location of centroid (quadrature point) */
  PetscScalar grad[2][3];  /* Face contribution to gradient in left and right cell */
} FaceGeom;

typedef struct {
  PetscScalar centroid[3];
  PetscScalar volume;
} CellGeom;

#endif