#ifndef PETSCMATCOARSEN_H
#define PETSCMATCOARSEN_H

#include <petscmat.h>

/* SUBMANSEC = Mat */

PETSC_EXTERN PetscFunctionList MatCoarsenList;

/*S
     MatCoarsen - Object for managing the coarsening of a graph (symmetric matrix)

   Level: advanced

  Notes:
    This is used by the PCGAMG to generate coarser representations of an algebraic problem

.seealso: `MatCoarsenCreate()`, `MatCoarsenType`
S*/
typedef struct _p_MatCoarsen* MatCoarsen;

/*J
    MatCoarsenType - String with the name of a PETSc matrix coarsen algorithm

   Level: beginner

.seealso: `MatCoarsenCreate()`, `MatCoarsen`
J*/
typedef const char* MatCoarsenType;
#define MATCOARSENMIS  "mis"
#define MATCOARSENHEM  "hem"

/* linked list for aggregates */
typedef struct _PetscCDIntNd{
  struct _PetscCDIntNd *next;
  PetscInt             gid;
}PetscCDIntNd;

/* only used by node pool */
typedef struct _PetscCDArrNd{
  struct _PetscCDArrNd *next;
  struct _PetscCDIntNd *array;
}PetscCDArrNd;

typedef struct _PetscCoarsenData{
  PetscCDArrNd pool_list;  /* node pool */
  PetscCDIntNd *new_node;
  PetscInt     new_left;
  PetscInt     chk_sz;
  PetscCDIntNd *extra_nodes;
  PetscCDIntNd **array;  /* Array of lists */
  PetscInt     size;
  Mat          mat;  /* cache a Mat for communication data */
}PetscCoarsenData;

PETSC_EXTERN PetscErrorCode MatCoarsenCreate(MPI_Comm,MatCoarsen*);
PETSC_EXTERN PetscErrorCode MatCoarsenSetType(MatCoarsen,MatCoarsenType);
PETSC_EXTERN PetscErrorCode MatCoarsenSetAdjacency(MatCoarsen,Mat);
PETSC_EXTERN PetscErrorCode MatCoarsenSetGreedyOrdering(MatCoarsen,const IS);
PETSC_EXTERN PetscErrorCode MatCoarsenSetStrictAggs(MatCoarsen,PetscBool);
PETSC_EXTERN PetscErrorCode MatCoarsenGetData(MatCoarsen, PetscCoarsenData **);
PETSC_EXTERN PetscErrorCode MatCoarsenApply(MatCoarsen);
PETSC_EXTERN PetscErrorCode MatCoarsenDestroy(MatCoarsen*);
PETSC_EXTERN PetscErrorCode MatCoarsenRegister(const char[],PetscErrorCode (*)(MatCoarsen));
PETSC_EXTERN PetscErrorCode MatCoarsenView(MatCoarsen,PetscViewer);
PETSC_EXTERN PetscErrorCode MatCoarsenSetFromOptions(MatCoarsen);
PETSC_EXTERN PetscErrorCode MatCoarsenGetType(MatCoarsen,MatCoarsenType*);
PETSC_EXTERN PetscErrorCode MatCoarsenViewFromOptions(MatCoarsen,PetscObject,const char[]);

PETSC_EXTERN PetscErrorCode PetscCDCreate(PetscInt,PetscCoarsenData**);
PETSC_EXTERN PetscErrorCode PetscCDDestroy(PetscCoarsenData*);
PETSC_EXTERN PetscErrorCode PetscCDIntNdSetID(PetscCDIntNd*,PetscInt);
PETSC_EXTERN PetscErrorCode PetscCDIntNdGetID(const PetscCDIntNd*,PetscInt*);
PETSC_EXTERN PetscErrorCode PetscCDAppendID(PetscCoarsenData*,PetscInt,PetscInt);
PETSC_EXTERN PetscErrorCode PetscCDAppendRemove(PetscCoarsenData*,PetscInt,PetscInt);
PETSC_EXTERN PetscErrorCode PetscCDAppendNode(PetscCoarsenData*,PetscInt,PetscCDIntNd*);
PETSC_EXTERN PetscErrorCode PetscCDRemoveNextNode(PetscCoarsenData*,PetscInt,PetscCDIntNd*);
PETSC_EXTERN PetscErrorCode PetscCDSizeAt(const PetscCoarsenData*,PetscInt,PetscInt*);
PETSC_EXTERN PetscErrorCode PetscCDEmptyAt(const PetscCoarsenData*,PetscInt,PetscBool*);
PETSC_EXTERN PetscErrorCode PetscCDSetChuckSize(PetscCoarsenData*,PetscInt);
PETSC_EXTERN PetscErrorCode PetscCDPrint(const PetscCoarsenData*,MPI_Comm);
PETSC_EXTERN PetscErrorCode PetscCDGetMIS(PetscCoarsenData*,IS*);
PETSC_EXTERN PetscErrorCode PetscCDGetMat(const PetscCoarsenData*,Mat*);
PETSC_EXTERN PetscErrorCode PetscCDSetMat(PetscCoarsenData*,Mat);

PETSC_EXTERN PetscErrorCode PetscCDGetHeadPos(const PetscCoarsenData*,PetscInt,PetscCDIntNd**);
PETSC_EXTERN PetscErrorCode PetscCDGetNextPos(const PetscCoarsenData*,PetscInt,PetscCDIntNd**);
PETSC_EXTERN PetscErrorCode PetscCDGetASMBlocks(const PetscCoarsenData*,const PetscInt,Mat,PetscInt*,IS**);

#endif