#include <petsc/private/dmimpl.h>
#include <petsc/private/tsimpl.h>   /*I "petscts.h" I*/

typedef struct {
  PetscErrorCode (*ifunctionlocal)(DM,PetscReal,Vec,Vec,Vec,void*);
  PetscErrorCode (*ijacobianlocal)(DM,PetscReal,Vec,Vec,PetscReal,Mat,Mat,void*);
  PetscErrorCode (*rhsfunctionlocal)(DM,PetscReal,Vec,Vec,void*);
  PetscErrorCode (*boundarylocal)(DM,Vec,void*);
  void *ifunctionlocalctx;
  void *ijacobianlocalctx;
  void *rhsfunctionlocalctx;
  void *boundarylocalctx;
} DMTS_Local;

#undef __FUNCT__
#define __FUNCT__ "DMTSDestroy_DMLocal"
static PetscErrorCode DMTSDestroy_DMLocal(DMTS tdm)
{
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = PetscFree(tdm->data);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMTSDuplicate_DMLocal"
static PetscErrorCode DMTSDuplicate_DMLocal(DMTS oldtdm, DMTS tdm)
{
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = PetscNewLog(tdm, (DMTS_Local **) &tdm->data);CHKERRQ(ierr);
  if (oldtdm->data) {ierr = PetscMemcpy(tdm->data, oldtdm->data, sizeof(DMTS_Local));CHKERRQ(ierr);}
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMLocalTSGetContext"
static PetscErrorCode DMLocalTSGetContext(DM dm, DMTS tdm, DMTS_Local **dmlocalts)
{
  PetscErrorCode ierr;

  PetscFunctionBegin;
  *dmlocalts = NULL;
  if (!tdm->data) {
    ierr = PetscNewLog(dm, (DMTS_Local **) &tdm->data);CHKERRQ(ierr);

    tdm->ops->destroy   = DMTSDestroy_DMLocal;
    tdm->ops->duplicate = DMTSDuplicate_DMLocal;
  }
  *dmlocalts = (DMTS_Local *) tdm->data;
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "TSComputeIFunction_DMLocal"
static PetscErrorCode TSComputeIFunction_DMLocal(TS ts, PetscReal time, Vec X, Vec X_t, Vec F, void *ctx)
{
  DM             dm;
  Vec            locX, locX_t, locF;
  DMTS_Local    *dmlocalts = (DMTS_Local *) ctx;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(ts,TS_CLASSID,1);
  PetscValidHeaderSpecific(X,VEC_CLASSID,3);
  PetscValidHeaderSpecific(X_t,VEC_CLASSID,4);
  PetscValidHeaderSpecific(F,VEC_CLASSID,5);
  ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
  ierr = DMGetLocalVector(dm, &locX);CHKERRQ(ierr);
  ierr = DMGetLocalVector(dm, &locX_t);CHKERRQ(ierr);
  ierr = DMGetLocalVector(dm, &locF);CHKERRQ(ierr);
  ierr = VecZeroEntries(locX);CHKERRQ(ierr);
  if (dmlocalts->boundarylocal) {ierr = (*dmlocalts->boundarylocal)(dm,locX,dmlocalts->boundarylocalctx);CHKERRQ(ierr);}
  ierr = VecZeroEntries(locX_t);CHKERRQ(ierr);
  ierr = DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
  ierr = DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
  ierr = DMGlobalToLocalBegin(dm, X_t, INSERT_VALUES, locX_t);CHKERRQ(ierr);
  ierr = DMGlobalToLocalEnd(dm, X_t, INSERT_VALUES, locX_t);CHKERRQ(ierr);
  ierr = VecZeroEntries(locF);CHKERRQ(ierr);
  CHKMEMQ;
  ierr = (*dmlocalts->ifunctionlocal)(dm, time, locX, locX_t, locF, dmlocalts->ifunctionlocalctx);CHKERRQ(ierr);
  CHKMEMQ;
  ierr = VecZeroEntries(F);CHKERRQ(ierr);
  ierr = DMLocalToGlobalBegin(dm, locF, ADD_VALUES, F);CHKERRQ(ierr);
  ierr = DMLocalToGlobalEnd(dm, locF, ADD_VALUES, F);CHKERRQ(ierr);
  ierr = DMRestoreLocalVector(dm, &locX);CHKERRQ(ierr);
  ierr = DMRestoreLocalVector(dm, &locX_t);CHKERRQ(ierr);
  ierr = DMRestoreLocalVector(dm, &locF);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "TSComputeRHSFunction_DMLocal"
static PetscErrorCode TSComputeRHSFunction_DMLocal(TS ts, PetscReal time, Vec X, Vec F, void *ctx)
{
  DM             dm;
  Vec            locX;
  DMTS_Local    *dmlocalts = (DMTS_Local *) ctx;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(ts,TS_CLASSID,1);
  PetscValidHeaderSpecific(X,VEC_CLASSID,3);
  PetscValidHeaderSpecific(F,VEC_CLASSID,5);
  ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
  ierr = DMGetLocalVector(dm, &locX);CHKERRQ(ierr);
  ierr = VecZeroEntries(locX);CHKERRQ(ierr);
  if (dmlocalts->boundarylocal) {ierr = (*dmlocalts->boundarylocal)(dm,locX,dmlocalts->boundarylocalctx);CHKERRQ(ierr);}
  ierr = DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
  ierr = DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
  ierr = VecZeroEntries(F);CHKERRQ(ierr);
  CHKMEMQ;
  ierr = (*dmlocalts->rhsfunctionlocal)(dm, time, locX, F, dmlocalts->rhsfunctionlocalctx);CHKERRQ(ierr);
  CHKMEMQ;
  ierr = DMRestoreLocalVector(dm, &locX);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "TSComputeIJacobian_DMLocal"
static PetscErrorCode TSComputeIJacobian_DMLocal(TS ts, PetscReal time, Vec X, Vec X_t, PetscReal a, Mat A, Mat B, void *ctx)
{
  DM             dm;
  Vec            locX, locX_t;
  DMTS_Local    *dmlocalts = (DMTS_Local *) ctx;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
  if (dmlocalts->ijacobianlocal) {
    ierr = DMGetLocalVector(dm, &locX);CHKERRQ(ierr);
    ierr = DMGetLocalVector(dm, &locX_t);CHKERRQ(ierr);
    ierr = VecZeroEntries(locX);CHKERRQ(ierr);
    if (dmlocalts->boundarylocal) {ierr = (*dmlocalts->boundarylocal)(dm,locX,dmlocalts->boundarylocalctx);CHKERRQ(ierr);}
    ierr = VecZeroEntries(locX_t);CHKERRQ(ierr);
    ierr = DMGlobalToLocalBegin(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
    ierr = DMGlobalToLocalEnd(dm, X, INSERT_VALUES, locX);CHKERRQ(ierr);
    ierr = DMGlobalToLocalBegin(dm, X_t, INSERT_VALUES, locX_t);CHKERRQ(ierr);
    ierr = DMGlobalToLocalEnd(dm, X_t, INSERT_VALUES, locX_t);CHKERRQ(ierr);
    CHKMEMQ;
    ierr = (*dmlocalts->ijacobianlocal)(dm, time, locX, locX_t, a, A, B, dmlocalts->ijacobianlocalctx);CHKERRQ(ierr);
    CHKMEMQ;
    ierr = DMRestoreLocalVector(dm, &locX);CHKERRQ(ierr);
    ierr = DMRestoreLocalVector(dm, &locX_t);CHKERRQ(ierr);
  } else {
    MatFDColoring fdcoloring;
    ierr = PetscObjectQuery((PetscObject) dm, "DMDASNES_FDCOLORING", (PetscObject *) &fdcoloring);CHKERRQ(ierr);
    if (!fdcoloring) {
      ISColoring coloring;

      ierr = DMCreateColoring(dm, dm->coloringtype, &coloring);CHKERRQ(ierr);
      ierr = MatFDColoringCreate(B, coloring, &fdcoloring);CHKERRQ(ierr);
      ierr = ISColoringDestroy(&coloring);CHKERRQ(ierr);
      switch (dm->coloringtype) {
      case IS_COLORING_GLOBAL:
        ierr = MatFDColoringSetFunction(fdcoloring, (PetscErrorCode (*)(void)) TSComputeIFunction_DMLocal, dmlocalts);CHKERRQ(ierr);
        break;
      default: SETERRQ1(PetscObjectComm((PetscObject) ts), PETSC_ERR_SUP, "No support for coloring type '%s'", ISColoringTypes[dm->coloringtype]);
      }
      ierr = PetscObjectSetOptionsPrefix((PetscObject) fdcoloring, ((PetscObject) dm)->prefix);CHKERRQ(ierr);
      ierr = MatFDColoringSetFromOptions(fdcoloring);CHKERRQ(ierr);
      ierr = MatFDColoringSetUp(B, coloring, fdcoloring);CHKERRQ(ierr);
      ierr = PetscObjectCompose((PetscObject) dm, "DMDASNES_FDCOLORING", (PetscObject) fdcoloring);CHKERRQ(ierr);
      ierr = PetscObjectDereference((PetscObject) fdcoloring);CHKERRQ(ierr);

      /* The following breaks an ugly reference counting loop that deserves a paragraph. MatFDColoringApply() will call
       * VecDuplicate() with the state Vec and store inside the MatFDColoring. This Vec will duplicate the Vec, but the
       * MatFDColoring is composed with the DM. We dereference the DM here so that the reference count will eventually
       * drop to 0. Note the code in DMDestroy() that exits early for a negative reference count. That code path will be
       * taken when the PetscObjectList for the Vec inside MatFDColoring is destroyed.
       */
      ierr = PetscObjectDereference((PetscObject) dm);CHKERRQ(ierr);
    }
    ierr = MatFDColoringApply(B, fdcoloring, X, ts);CHKERRQ(ierr);
  }
  /* This will be redundant if the user called both, but it's too common to forget. */
  if (A != B) {
    ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
    ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMTSSetBoundaryLocal"
/*@C
  DMTSSetBoundaryLocal - set a local boundary value function. This function is called with local vector
    containing the local vector information PLUS ghost point information. It should insert values into the
    local vector that do not come from the global vector, such as essential boundary condition data.

  Logically Collective

  Input Arguments:
+ dm   - DM to associate callback with
. func - local boundary value evaluation
- ctx  - optional context for local boundary value evaluation

  Level: intermediate

.seealso: DMTSSetIFunctionLocal(), DMTSetIJacobianLocal(), DMSNESSetBoundaryLocal(), DMSNESSetFunctionLocal()
@*/
PetscErrorCode DMTSSetBoundaryLocal(DM dm, PetscErrorCode (*func)(DM, Vec, void *), void *ctx)
{
  DMTS           tdm;
  DMTS_Local    *dmlocalts;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
  ierr = DMGetDMTSWrite(dm, &tdm);CHKERRQ(ierr);
  ierr = DMLocalTSGetContext(dm, tdm, &dmlocalts);CHKERRQ(ierr);

  dmlocalts->boundarylocal    = func;
  dmlocalts->boundarylocalctx = ctx;
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMTSSetIFunctionLocal"
/*@C
  DMTSSetIFunctionLocal - set a local implicit function evaluation function. This function is called with local vector
      containing the local vector information PLUS ghost point information. It should compute a result for all local
      elements and DMTS will automatically accumulate the overlapping values.

  Logically Collective

  Input Arguments:
+ dm   - DM to associate callback with
. func - local function evaluation
- ctx  - context for function evaluation

  Level: beginner

.seealso: DMTSSetIFunction(), DMTSSetIJacobianLocal()
@*/
PetscErrorCode DMTSSetIFunctionLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, Vec, void *), void *ctx)
{
  DMTS           tdm;
  DMTS_Local    *dmlocalts;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(dm,DM_CLASSID,1);
  ierr = DMGetDMTSWrite(dm, &tdm);CHKERRQ(ierr);
  ierr = DMLocalTSGetContext(dm, tdm, &dmlocalts);CHKERRQ(ierr);

  dmlocalts->ifunctionlocal    = func;
  dmlocalts->ifunctionlocalctx = ctx;

  ierr = DMTSSetIFunction(dm, TSComputeIFunction_DMLocal, dmlocalts);CHKERRQ(ierr);
  if (!tdm->ops->ijacobian) {  /* Call us for the Jacobian too, can be overridden by the user. */
    ierr = DMTSSetIJacobian(dm, TSComputeIJacobian_DMLocal, dmlocalts);CHKERRQ(ierr);
  }
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMTSSetIJacobianLocal"
/*@C
  DMTSSetIJacobianLocal - set a local Jacobian evaluation function

  Logically Collective

  Input Arguments:
+ dm - DM to associate callback with
. func - local Jacobian evaluation
- ctx - optional context for local Jacobian evaluation

  Level: beginner

.seealso: DMTSSetIFunctionLocal(), DMTSSetIJacobian(), DMTSSetIFunction()
@*/
PetscErrorCode DMTSSetIJacobianLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, PetscReal, Mat, Mat, void *), void *ctx)
{
  DMTS           tdm;
  DMTS_Local    *dmlocalts;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(dm,DM_CLASSID,1);
  ierr = DMGetDMTSWrite(dm, &tdm);CHKERRQ(ierr);
  ierr = DMLocalTSGetContext(dm, tdm, &dmlocalts);CHKERRQ(ierr);

  dmlocalts->ijacobianlocal    = func;
  dmlocalts->ijacobianlocalctx = ctx;

  ierr = DMTSSetIJacobian(dm, TSComputeIJacobian_DMLocal, dmlocalts);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}

#undef __FUNCT__
#define __FUNCT__ "DMTSSetRHSFunctionLocal"
/*@C
  DMTSSetRHSFunctionLocal - set a local rhs function evaluation function. This function is called with local vector
      containing the local vector information PLUS ghost point information. It should compute a result for all local
      elements and DMTS will automatically accumulate the overlapping values.

  Logically Collective

  Input Arguments:
+ dm   - DM to associate callback with
. func - local function evaluation
- ctx  - context for function evaluation

  Level: beginner

.seealso: DMTSSetRHSFunction(), DMTSSetIFunction(), DMTSSetIJacobianLocal()
@*/
PetscErrorCode DMTSSetRHSFunctionLocal(DM dm, PetscErrorCode (*func)(DM, PetscReal, Vec, Vec, void *), void *ctx)
{
  DMTS           tdm;
  DMTS_Local    *dmlocalts;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  PetscValidHeaderSpecific(dm,DM_CLASSID,1);
  ierr = DMGetDMTSWrite(dm, &tdm);CHKERRQ(ierr);
  ierr = DMLocalTSGetContext(dm, tdm, &dmlocalts);CHKERRQ(ierr);

  dmlocalts->rhsfunctionlocal    = func;
  dmlocalts->rhsfunctionlocalctx = ctx;

  ierr = DMTSSetRHSFunction(dm, TSComputeRHSFunction_DMLocal, dmlocalts);CHKERRQ(ierr);
  PetscFunctionReturn(0);
}
