static char help[] = "Tests various 3-dimensional DMDA routines.\n\n";

#include <petscdm.h>
#include <petscdmda.h>
#include <petscao.h>

int main(int argc, char **argv)
{
  PetscMPIInt     rank;
  PetscInt        M = 3, N = 5, P = 3, s = 1, w = 2, nloc, l, i, j, k, kk, m = PETSC_DECIDE, n = PETSC_DECIDE, p = PETSC_DECIDE;
  PetscInt        Xs, Xm, Ys, Ym, Zs, Zm, iloc, *iglobal;
  const PetscInt *ltog;
  PetscInt       *lx = NULL, *ly = NULL, *lz = NULL;
  PetscBool       test_order = PETSC_FALSE;
  DM              da;
  PetscViewer     viewer;
  Vec             local, global;
  PetscScalar     value;
  DMBoundaryType  bx = DM_BOUNDARY_NONE, by = DM_BOUNDARY_NONE, bz = DM_BOUNDARY_NONE;
  DMDAStencilType stencil_type = DMDA_STENCIL_BOX;
  AO              ao;
  PetscBool       flg = PETSC_FALSE;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
  PetscCall(PetscViewerDrawOpen(PETSC_COMM_WORLD, 0, "", 300, 0, 400, 300, &viewer));

  /* Read options */
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-NX", &M, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-NY", &N, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-NZ", &P, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-p", &p, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-s", &s, NULL));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-w", &w, NULL));
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-star", &flg, NULL));
  if (flg) stencil_type = DMDA_STENCIL_STAR;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-box", &flg, NULL));
  if (flg) stencil_type = DMDA_STENCIL_BOX;

  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-xperiodic", &flg, NULL));
  if (flg) bx = DM_BOUNDARY_PERIODIC;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-xghosted", &flg, NULL));
  if (flg) bx = DM_BOUNDARY_GHOSTED;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-xnonghosted", &flg, NULL));

  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-yperiodic", &flg, NULL));
  if (flg) by = DM_BOUNDARY_PERIODIC;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-yghosted", &flg, NULL));
  if (flg) by = DM_BOUNDARY_GHOSTED;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-ynonghosted", &flg, NULL));

  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-zperiodic", &flg, NULL));
  if (flg) bz = DM_BOUNDARY_PERIODIC;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-zghosted", &flg, NULL));
  if (flg) bz = DM_BOUNDARY_GHOSTED;
  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-znonghosted", &flg, NULL));

  PetscCall(PetscOptionsGetBool(NULL, NULL, "-testorder", &test_order, NULL));

  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-distribute", &flg, NULL));
  if (flg) {
    PetscCheck(m != PETSC_DECIDE, PETSC_COMM_WORLD, PETSC_ERR_USER_INPUT, "Must set -m option with -distribute option");
    PetscCall(PetscMalloc1(m, &lx));
    for (i = 0; i < m - 1; i++) lx[i] = 4;
    lx[m - 1] = M - 4 * (m - 1);
    PetscCheck(n != PETSC_DECIDE, PETSC_COMM_WORLD, PETSC_ERR_USER_INPUT, "Must set -n option with -distribute option");
    PetscCall(PetscMalloc1(n, &ly));
    for (i = 0; i < n - 1; i++) ly[i] = 2;
    ly[n - 1] = N - 2 * (n - 1);
    PetscCheck(p != PETSC_DECIDE, PETSC_COMM_WORLD, PETSC_ERR_USER_INPUT, "Must set -p option with -distribute option");
    PetscCall(PetscMalloc1(p, &lz));
    for (i = 0; i < p - 1; i++) lz[i] = 2;
    lz[p - 1] = P - 2 * (p - 1);
  }

  /* Create distributed array and get vectors */
  PetscCall(DMDACreate3d(PETSC_COMM_WORLD, bx, by, bz, stencil_type, M, N, P, m, n, p, w, s, lx, ly, lz, &da));
  PetscCall(DMSetFromOptions(da));
  PetscCall(DMSetUp(da));
  PetscCall(PetscFree(lx));
  PetscCall(PetscFree(ly));
  PetscCall(PetscFree(lz));
  PetscCall(DMView(da, viewer));
  PetscCall(DMCreateGlobalVector(da, &global));
  PetscCall(DMCreateLocalVector(da, &local));

  /* Set global vector; send ghost points to local vectors */
  value = 1;
  PetscCall(VecSet(global, value));
  PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
  PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));

  /* Scale local vectors according to processor rank; pass to global vector */
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
  value = rank;
  PetscCall(VecScale(local, value));
  PetscCall(DMLocalToGlobalBegin(da, local, INSERT_VALUES, global));
  PetscCall(DMLocalToGlobalEnd(da, local, INSERT_VALUES, global));

  if (!test_order) { /* turn off printing when testing ordering mappings */
    if (M * N * P < 40) {
      PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\nGlobal Vector:\n"));
      PetscCall(VecView(global, PETSC_VIEWER_STDOUT_WORLD));
      PetscCall(PetscPrintf(PETSC_COMM_WORLD, "\n"));
    }
  }

  /* Send ghost points to local vectors */
  PetscCall(DMGlobalToLocalBegin(da, global, INSERT_VALUES, local));
  PetscCall(DMGlobalToLocalEnd(da, global, INSERT_VALUES, local));

  flg = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-local_print", &flg, NULL));
  if (flg) {
    PetscViewer sviewer;
    PetscCall(PetscViewerASCIIPushSynchronized(PETSC_VIEWER_STDOUT_WORLD));
    PetscCall(PetscSynchronizedPrintf(PETSC_COMM_WORLD, "\nLocal Vector: processor %d\n", rank));
    PetscCall(PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
    PetscCall(VecView(local, sviewer));
    PetscCall(PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD, PETSC_COMM_SELF, &sviewer));
    PetscCall(PetscSynchronizedFlush(PETSC_COMM_WORLD, PETSC_STDOUT));
    PetscCall(PetscViewerASCIIPopSynchronized(PETSC_VIEWER_STDOUT_WORLD));
  }

  /* Tests mappings between application/PETSc orderings */
  if (test_order) {
    ISLocalToGlobalMapping ltogm;

    PetscCall(DMGetLocalToGlobalMapping(da, &ltogm));
    PetscCall(ISLocalToGlobalMappingGetSize(ltogm, &nloc));
    PetscCall(ISLocalToGlobalMappingGetIndices(ltogm, &ltog));

    PetscCall(DMDAGetGhostCorners(da, &Xs, &Ys, &Zs, &Xm, &Ym, &Zm));
    PetscCall(DMDAGetAO(da, &ao));
    /* PetscCall(AOView(ao,PETSC_VIEWER_STDOUT_WORLD)); */
    PetscCall(PetscMalloc1(nloc, &iglobal));

    /* Set iglobal to be global indices for each processor's local and ghost nodes,
       using the DMDA ordering of grid points */
    kk = 0;
    for (k = Zs; k < Zs + Zm; k++) {
      for (j = Ys; j < Ys + Ym; j++) {
        for (i = Xs; i < Xs + Xm; i++) {
          iloc = w * ((k - Zs) * Xm * Ym + (j - Ys) * Xm + i - Xs);
          for (l = 0; l < w; l++) iglobal[kk++] = ltog[iloc + l];
        }
      }
    }

    /* Map this to the application ordering (which for DMDAs is just the natural ordering
       that would be used for 1 processor, numbering most rapidly by x, then y, then z) */
    PetscCall(AOPetscToApplication(ao, nloc, iglobal));

    /* Then map the application ordering back to the PETSc DMDA ordering */
    PetscCall(AOApplicationToPetsc(ao, nloc, iglobal));

    /* Verify the mappings */
    kk = 0;
    for (k = Zs; k < Zs + Zm; k++) {
      for (j = Ys; j < Ys + Ym; j++) {
        for (i = Xs; i < Xs + Xm; i++) {
          iloc = w * ((k - Zs) * Xm * Ym + (j - Ys) * Xm + i - Xs);
          for (l = 0; l < w; l++) {
            if (iglobal[kk] != ltog[iloc + l]) {
              PetscCall(PetscPrintf(MPI_COMM_WORLD, "[%d] Problem with mapping: z=%" PetscInt_FMT ", j=%" PetscInt_FMT ", i=%" PetscInt_FMT ", l=%" PetscInt_FMT ", petsc1=%" PetscInt_FMT ", petsc2=%" PetscInt_FMT "\n", rank, k, j, i, l, ltog[iloc + l], iglobal[kk]));
            }
            kk++;
          }
        }
      }
    }
    PetscCall(PetscFree(iglobal));
    PetscCall(ISLocalToGlobalMappingRestoreIndices(ltogm, &ltog));
  }

  /* Free memory */
  PetscCall(PetscViewerDestroy(&viewer));
  PetscCall(VecDestroy(&local));
  PetscCall(VecDestroy(&global));
  PetscCall(DMDestroy(&da));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

    test:
      args:  -testorder -nox

 TEST*/
