#pragma once

#define KSPGMRES_NO_MACROS
#include <../src/ksp/ksp/impls/gmres/gmresimpl.h>

typedef struct {
  KSPGMRESHEADER

  /* new storage for fgmres */
  Vec  *prevecs;           /* holds the preconditioned basis vectors for fgmres.
                                    We will allocate these at the same time as vecs
                                    above (and in the same "chunks". */
  Vec **prevecs_user_work; /* same purpose as user_work above, but this one is
                                    for our preconditioned vectors */

  /* we need a function for interacting with the pcfamily */

  KSPFlexibleModifyPCFn *modifypc; /* function to modify the preconditioner*/
  PetscCtxDestroyFn     *modifydestroy;
  void                  *modifyctx;
} KSP_FGMRES;

#define HH(a, b) (fgmres->hh_origin + (b) * (fgmres->max_k + 2) + (a))
/* HH will be size (max_k+2)*(max_k+1)  -  think of HH as
   being stored columnwise for access purposes. */
#define HES(a, b) (fgmres->hes_origin + (b) * (fgmres->max_k + 1) + (a))
/* HES will be size (max_k + 1) * (max_k + 1) -
   again, think of HES as being stored columnwise */
#define CC(a) (fgmres->cc_origin + (a)) /* CC will be length (max_k+1) - cosines */
#define SS(a) (fgmres->ss_origin + (a)) /* SS will be length (max_k+1) - sines */
#define RS(a) (fgmres->rs_origin + (a)) /* RS will be length (max_k+2) - rt side */

/* vector names */
#define VEC_OFFSET     2
#define VEC_TEMP       fgmres->vecs[0] /* work space */
#define VEC_TEMP_MATOP fgmres->vecs[1] /* work space */
#define VEC_VV(i) \
  fgmres->vecs[VEC_OFFSET + i] /* use to access
                                                        othog basis vectors */
#define PREVEC(i) \
  fgmres->prevecs[i] /* use to access
                                                        preconditioned basis */