#pragma once

#include <petsc/private/pcimpl.h> /*I "petscpc.h" I*/
#include <petscksp.h>

typedef struct {
  PetscBool   init;    /* do only init step - error correction of direction is omitted */
  PetscBool   correct; /* add CP (Qr) correction to descent direction */
  PetscScalar correctfact;
  PetscInt    reductionfact;
  Mat         W, Wt, WtA, WtAW; /* deflation space, coarse problem mats */
  KSP         WtAWinv;          /* deflation coarse problem */
  KSPType     ksptype;
  PC          pc; /* additional preconditioner */
  Vec         work;
  Vec        *workcoarse;
  const char *prefix;

  PCDeflationSpaceType spacetype;
  PetscInt             spacesize;
  PetscInt             lvl;
  PetscInt             maxlvl;
  PetscBool            extendsp;
} PC_Deflation;

PETSC_INTERN PetscErrorCode PCDeflationComputeSpace(PC);