// SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
// SPDX-License-Identifier: BSD-3-Clause
#include "vtkTransmitUnstructuredGridPiece.h"

#include "vtkCellData.h"
#include "vtkExtractUnstructuredGridPiece.h"
#include "vtkInformation.h"
#include "vtkInformationVector.h"
#include "vtkMultiProcessController.h"
#include "vtkObjectFactory.h"
#include "vtkPointData.h"
#include "vtkStreamingDemandDrivenPipeline.h"
#include "vtkUnstructuredGrid.h"

#include <iostream>

VTK_ABI_NAMESPACE_BEGIN
vtkStandardNewMacro(vtkTransmitUnstructuredGridPiece);

vtkCxxSetObjectMacro(vtkTransmitUnstructuredGridPiece, Controller, vtkMultiProcessController);

//------------------------------------------------------------------------------
vtkTransmitUnstructuredGridPiece::vtkTransmitUnstructuredGridPiece()
{
  this->CreateGhostCells = 1;

  // Controller keeps a reference to this object as well.
  this->Controller = nullptr;
  this->SetController(vtkMultiProcessController::GetGlobalController());
}

//------------------------------------------------------------------------------
vtkTransmitUnstructuredGridPiece::~vtkTransmitUnstructuredGridPiece()
{
  this->SetController(nullptr);
}

//------------------------------------------------------------------------------
int vtkTransmitUnstructuredGridPiece::RequestData(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  // get the info objects
  vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
  vtkInformation* outInfo = outputVector->GetInformationObject(0);

  // get the input and output
  vtkUnstructuredGrid* input =
    vtkUnstructuredGrid::SafeDownCast(inInfo->Get(vtkDataObject::DATA_OBJECT()));
  vtkUnstructuredGrid* output =
    vtkUnstructuredGrid::SafeDownCast(outInfo->Get(vtkDataObject::DATA_OBJECT()));

  int procId;

  if (this->Controller == nullptr)
  {
    vtkErrorMacro("Could not find Controller.");
    return 1;
  }

  procId = this->Controller->GetLocalProcessId();
  if (procId == 0)
  {
    // std::cerr << "Root Execute\n";
    this->RootExecute(input, output, outInfo);
  }
  else
  {
    // std::cerr << "Satellite Execute " << procId << endl;
    this->SatelliteExecute(procId, output, outInfo);
  }

  return 1;
}

//------------------------------------------------------------------------------
void vtkTransmitUnstructuredGridPiece::RootExecute(
  vtkUnstructuredGrid* input, vtkUnstructuredGrid* output, vtkInformation* outInfo)
{
  vtkUnstructuredGrid* tmp = vtkUnstructuredGrid::New();
  vtkExtractUnstructuredGridPiece* extract = vtkExtractUnstructuredGridPiece::New();
  int ext[3];
  int numProcs, i;

  int outPiece = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_PIECE_NUMBER());
  if (outPiece != 0)
  {
    vtkWarningMacro(<< "Piece " << outPiece << " does not match process 0.  "
                    << "Altering request to try to avoid a deadlock.");
  }

  vtkStreamingDemandDrivenPipeline* extractExecutive =
    vtkStreamingDemandDrivenPipeline::SafeDownCast(extract->GetExecutive());

  // First, set up the pipeline and handle local request.
  tmp->ShallowCopy(input);
  extract->SetCreateGhostCells(this->CreateGhostCells);
  extract->SetInputData(tmp);
  extractExecutive->UpdateDataObject();

  vtkInformation* extractOutInfo = extractExecutive->GetOutputInformation(0);
  extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_PIECES(),
    outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_PIECES()));
  extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_PIECE_NUMBER(),
    outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_PIECE_NUMBER()));
  extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_GHOST_LEVELS(),
    outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_GHOST_LEVELS()));
  extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_EXTENT_INITIALIZED(), 1);

  extract->Update();

  // Copy geometry without copying information.
  output->CopyStructure(extract->GetOutput());
  output->GetPointData()->PassData(extract->GetOutput()->GetPointData());
  output->GetCellData()->PassData(extract->GetOutput()->GetCellData());
  vtkFieldData* inFd = extract->GetOutput()->GetFieldData();
  vtkFieldData* outFd = output->GetFieldData();
  if (inFd && outFd)
  {
    outFd->PassData(inFd);
  }

  // Now do each of the satellite requests.
  numProcs = this->Controller->GetNumberOfProcesses();
  for (i = 1; i < numProcs; ++i)
  {
    this->Controller->Receive(ext, 3, i, 22341);
    extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_PIECES(), ext[1]);
    extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_PIECE_NUMBER(), ext[0]);
    extractOutInfo->Set(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_GHOST_LEVELS(), ext[2]);
    extract->Update();
    this->Controller->Send(extract->GetOutput(), i, 22342);
  }
  tmp->Delete();
  extract->Delete();
}

//------------------------------------------------------------------------------
void vtkTransmitUnstructuredGridPiece::SatelliteExecute(
  int, vtkUnstructuredGrid* output, vtkInformation* outInfo)
{
  vtkUnstructuredGrid* tmp = vtkUnstructuredGrid::New();
  int ext[3];

  ext[0] = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_PIECE_NUMBER());
  ext[1] = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_PIECES());
  ext[2] = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_NUMBER_OF_GHOST_LEVELS());

  this->Controller->Send(ext, 3, 0, 22341);
  this->Controller->Receive(tmp, 0, 22342);

  // Copy geometry without copying information.
  output->CopyStructure(tmp);
  output->GetPointData()->PassData(tmp->GetPointData());
  output->GetCellData()->PassData(tmp->GetCellData());

  tmp->Delete();
}

//------------------------------------------------------------------------------
void vtkTransmitUnstructuredGridPiece::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);

  os << indent << "Create Ghost Cells: " << (this->CreateGhostCells ? "On\n" : "Off\n");

  os << indent << "Controller: (" << this->Controller << ")\n";
}
VTK_ABI_NAMESPACE_END