static char help[] = "Tests binary viewers.\n\n";

#include <petscsys.h>
#include <petscviewer.h>

static PetscErrorCode TestOpen(PetscFileMode mode, PetscViewer *viewer)
{
  const char *name;
  PetscBool   skipinfo, skipheader, skipoptions;

  PetscFunctionBegin;
  PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "binary.dat", mode, viewer));
  PetscCall(PetscViewerBinarySkipInfo(*viewer));
  PetscCall(PetscViewerBinarySetSkipInfo(*viewer, PETSC_FALSE));
  PetscCall(PetscViewerBinarySetSkipHeader(*viewer, PETSC_FALSE));
  PetscCall(PetscViewerBinarySetSkipOptions(*viewer, PETSC_FALSE));
  PetscCall(PetscViewerSetUp(*viewer));
  PetscCall(PetscViewerFileGetName(*viewer, &name));
  PetscCall(PetscViewerFileGetMode(*viewer, &mode));
  PetscCall(PetscViewerBinaryGetSkipInfo(*viewer, &skipinfo));
  PetscCall(PetscViewerBinaryGetSkipHeader(*viewer, &skipheader));
  PetscCall(PetscViewerBinaryGetSkipOptions(*viewer, &skipoptions));
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode TestWrite(PetscViewer viewer)
{
  PetscInt    idata = 42;
  PetscReal   rdata = 42;
  PetscInt    s = PETSC_DETERMINE, t = PETSC_DETERMINE;
  PetscViewer subviewer;

  PetscFunctionBegin;
  PetscCall(PetscViewerBinaryWrite(viewer, &idata, 1, PETSC_INT));
  PetscCall(PetscViewerBinaryWrite(viewer, &rdata, 1, PETSC_REAL));

  PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &subviewer));
  if (subviewer) {
    PetscCall(PetscViewerBinaryWrite(subviewer, &idata, 1, PETSC_INT));
    PetscCall(PetscViewerBinaryWrite(subviewer, &rdata, 1, PETSC_REAL));
  }
  PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &subviewer));

  PetscCall(PetscViewerBinaryWriteAll(viewer, &idata, 1, s, t, PETSC_INT));
  PetscCall(PetscViewerBinaryWriteAll(viewer, &rdata, 1, s, t, PETSC_REAL));

  PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &subviewer));
  if (subviewer) {
    PetscCall(PetscViewerBinaryWrite(subviewer, &idata, 1, PETSC_INT));
    PetscCall(PetscViewerBinaryWrite(subviewer, &rdata, 1, PETSC_REAL));
  }
  PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &subviewer));

  PetscCall(PetscViewerBinaryWrite(viewer, &idata, 1, PETSC_INT));
  PetscCall(PetscViewerBinaryWrite(viewer, &rdata, 1, PETSC_REAL));
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode TestRead(PetscViewer viewer)
{
  PetscInt    idata = 0;
  PetscReal   rdata = 0;
  PetscInt    s = PETSC_DETERMINE, t = PETSC_DETERMINE;
  PetscViewer subviewer;
  MPI_Comm    comm = PetscObjectComm((PetscObject)viewer);

  PetscFunctionBegin;
  PetscCall(PetscViewerBinaryRead(viewer, &idata, 1, NULL, PETSC_INT));
  PetscCall(PetscViewerBinaryRead(viewer, &rdata, 1, NULL, PETSC_REAL));
  PetscCheck(idata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected idata=%" PetscInt_FMT, idata);
  PetscCheck(rdata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected rdata=%g", (double)rdata);

  PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &subviewer));
  if (subviewer) {
    MPI_Comm subcomm = PetscObjectComm((PetscObject)subviewer);
    PetscCall(PetscViewerBinaryRead(subviewer, &idata, 1, NULL, PETSC_INT));
    PetscCall(PetscViewerBinaryRead(subviewer, &rdata, 1, NULL, PETSC_REAL));
    PetscCheck(idata == 42, subcomm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected idata=%" PetscInt_FMT, idata);
    PetscCheck(rdata == 42, subcomm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected rdata=%g", (double)rdata);
  }
  PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &subviewer));

  PetscCall(PetscViewerBinaryReadAll(viewer, &idata, 1, s, t, PETSC_INT));
  PetscCall(PetscViewerBinaryReadAll(viewer, &rdata, 1, s, t, PETSC_REAL));
  PetscCheck(idata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected idata=%" PetscInt_FMT, idata);
  PetscCheck(rdata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected rdata=%g", (double)rdata);

  PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &subviewer));
  if (subviewer) {
    MPI_Comm subcomm = PetscObjectComm((PetscObject)subviewer);
    PetscCall(PetscViewerBinaryRead(subviewer, &idata, 1, NULL, PETSC_INT));
    PetscCall(PetscViewerBinaryRead(subviewer, &rdata, 1, NULL, PETSC_REAL));
    PetscCheck(idata == 42, subcomm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected idata=%" PetscInt_FMT, idata);
    PetscCheck(rdata == 42, subcomm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected rdata=%g", (double)rdata);
  }
  PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &subviewer));

  PetscCall(PetscViewerBinaryRead(viewer, &idata, 1, NULL, PETSC_INT));
  PetscCall(PetscViewerBinaryRead(viewer, &rdata, 1, NULL, PETSC_REAL));
  PetscCheck(idata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected idata=%" PetscInt_FMT, idata);
  PetscCheck(rdata == 42, comm, PETSC_ERR_FILE_UNEXPECTED, "Unexpected rdata=%g", (double)rdata);
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode TestEOF(PetscViewer viewer)
{
  char     data;
  PetscInt count = PETSC_INT_MAX;
  MPI_Comm comm  = PetscObjectComm((PetscObject)viewer);

  PetscFunctionBegin;
  PetscCall(PetscViewerRead(viewer, &data, 1, &count, PETSC_CHAR));
  PetscCheck(!count, comm, PETSC_ERR_FILE_UNEXPECTED, "Expected EOF");
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode TestClose(PetscViewer *viewer)
{
  PetscFileMode mode;

  PetscFunctionBegin;
  PetscCall(PetscViewerFileGetMode(*viewer, &mode));
  if (mode == FILE_MODE_READ) PetscCall(TestEOF(*viewer));
  PetscCall(PetscViewerDestroy(viewer));
  PetscFunctionReturn(PETSC_SUCCESS);
}

int main(int argc, char **args)
{
  PetscViewer viewer;

  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &args, NULL, help));

  PetscCall(TestOpen(FILE_MODE_WRITE, &viewer));
  PetscCall(TestWrite(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_APPEND, &viewer));
  PetscCall(TestWrite(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_APPEND, &viewer));
  PetscCall(TestWrite(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_WRITE, &viewer));
  PetscCall(TestWrite(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestRead(viewer));
  PetscCall(TestClose(&viewer));

  PetscCall(TestOpen(FILE_MODE_WRITE, &viewer));
  PetscCall(TestClose(&viewer));
  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestClose(&viewer));
  PetscCall(TestOpen(FILE_MODE_APPEND, &viewer));
  PetscCall(TestClose(&viewer));
  PetscCall(TestOpen(FILE_MODE_READ, &viewer));
  PetscCall(TestClose(&viewer));

  {
    FILE       *info;
    PetscMPIInt rank;

    PetscCall(TestOpen(FILE_MODE_WRITE, &viewer));
    PetscCall(PetscViewerPushFormat(viewer, PETSC_VIEWER_BINARY_MATLAB));
    PetscCall(PetscViewerBinaryGetInfoPointer(viewer, &info));
    PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer), &rank));
    PetscCheck(rank != 0 || info, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Missing info pointer");
    PetscCall(TestClose(&viewer));
  }

  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   testset:
     nsize: {{1 2 3}separate_output}
     args: -viewer_view
     test:
       suffix: stdio
       args: -viewer_binary_mpiio 0
     test:
       requires: mpiio
       suffix: mpiio
       args: -viewer_binary_mpiio 1

TEST*/