/*=========================================================================

 Program:   Visualization Toolkit
 Module:    vtkDataSetGhostGenerator.cxx

 Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
 All rights reserved.
 See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

 This software is distributed WITHOUT ANY WARRANTY; without even
 the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 PURPOSE.  See the above copyright notice for more information.

 =========================================================================*/
#include "vtkDataSetGhostGenerator.h"
#include "vtkDataObject.h"
#include "vtkIndent.h"
#include "vtkInformation.h"
#include "vtkInformationVector.h"
#include "vtkMultiBlockDataSet.h"

#include <cassert>

vtkDataSetGhostGenerator::vtkDataSetGhostGenerator()
{
  this->NumberOfGhostLayers = 0;
  this->SetNumberOfInputPorts(1);
  this->SetNumberOfOutputPorts(1);
}

//------------------------------------------------------------------------------
vtkDataSetGhostGenerator::~vtkDataSetGhostGenerator() = default;

//------------------------------------------------------------------------------
void vtkDataSetGhostGenerator::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);
  os << "NumberOfGhostLayers: " << this->NumberOfGhostLayers << std::endl;
}

//------------------------------------------------------------------------------
int vtkDataSetGhostGenerator::FillInputPortInformation(int vtkNotUsed(port), vtkInformation* info)
{
  assert("pre: information object is nullptr!" && (info != nullptr));
  info->Set(vtkAlgorithm::INPUT_REQUIRED_DATA_TYPE(), "vtkMultiBlockDataSet");
  return 1;
}

//------------------------------------------------------------------------------
int vtkDataSetGhostGenerator::FillOutputPortInformation(int vtkNotUsed(port), vtkInformation* info)
{
  assert("pre: information object is nullptr!" && (info != nullptr));

  info->Set(vtkDataObject::DATA_TYPE_NAME(), "vtkMultiBlockDataSet");
  return 1;
}

//------------------------------------------------------------------------------
int vtkDataSetGhostGenerator::RequestData(vtkInformation* vtkNotUsed(rqst),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{

  // STEP 0: Get input object
  vtkInformation* input = inputVector[0]->GetInformationObject(0);
  assert("pre: Null input object!" && (input != nullptr));
  vtkMultiBlockDataSet* inputMultiBlock =
    vtkMultiBlockDataSet::SafeDownCast(input->Get(vtkDataObject::DATA_OBJECT()));
  assert("pre: Input multi-block object is nullptr" && (inputMultiBlock != nullptr));

  // STEP 1: Get output object
  vtkInformation* output = outputVector->GetInformationObject(0);
  assert("pre: Null output object!" && (output != nullptr));
  vtkMultiBlockDataSet* outputMultiBlock =
    vtkMultiBlockDataSet::SafeDownCast(output->Get(vtkDataObject::DATA_OBJECT()));
  assert("pre: Outpu multi-block object is nullptr" && (outputMultiBlock != nullptr));

  // STEP 2: Generate ghost layers
  if (this->NumberOfGhostLayers == 0)
  {
    // Shallow copy the input object
    outputMultiBlock->ShallowCopy(inputMultiBlock);
  }
  else
  {
    // Create requested ghost layers
    this->GenerateGhostLayers(inputMultiBlock, outputMultiBlock);
  }
  return 1;
}
