/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         https://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#ifndef itkClosingByReconstructionImageFilter_hxx
#define itkClosingByReconstructionImageFilter_hxx

#include "itkImageRegionIterator.h"
#include "itkGrayscaleDilateImageFilter.h"
#include "itkReconstructionByErosionImageFilter.h"
#include "itkProgressAccumulator.h"

namespace itk
{
template <typename TInputImage, typename TOutputImage, typename TKernel>
ClosingByReconstructionImageFilter<TInputImage, TOutputImage, TKernel>::ClosingByReconstructionImageFilter()
  : m_Kernel()
{
  m_FullyConnected = false;
  m_PreserveIntensities = false;
}

template <typename TInputImage, typename TOutputImage, typename TKernel>
void
ClosingByReconstructionImageFilter<TInputImage, TOutputImage, TKernel>::GenerateInputRequestedRegion()
{
  // call the superclass' implementation of this method
  Superclass::GenerateInputRequestedRegion();

  // We need all the input.
  InputImagePointer input = const_cast<InputImageType *>(this->GetInput());
  if (input)
  {
    input->SetRequestedRegion(input->GetLargestPossibleRegion());
  }
}

template <typename TInputImage, typename TOutputImage, typename TKernel>
void
ClosingByReconstructionImageFilter<TInputImage, TOutputImage, TKernel>::EnlargeOutputRequestedRegion(DataObject *)
{
  this->GetOutput()->SetRequestedRegion(this->GetOutput()->GetLargestPossibleRegion());
}

template <typename TInputImage, typename TOutputImage, typename TKernel>
void
ClosingByReconstructionImageFilter<TInputImage, TOutputImage, TKernel>::GenerateData()
{
  // Create a process accumulator for tracking the progress of this minipipeline
  auto progress = ProgressAccumulator::New();

  progress->SetMiniPipelineFilter(this);

  // Allocate the output
  this->AllocateOutputs();

  // Delegate to a dilate filter.
  typename GrayscaleDilateImageFilter<TInputImage, TInputImage, TKernel>::Pointer dilate =
    GrayscaleDilateImageFilter<TInputImage, TInputImage, TKernel>::New();

  dilate->SetInput(this->GetInput());
  dilate->SetKernel(this->m_Kernel);

  progress->RegisterInternalFilter(dilate, .5);

  // Delegate to a dilate filter.
  typename ReconstructionByErosionImageFilter<TInputImage, TInputImage>::Pointer erode =
    ReconstructionByErosionImageFilter<TInputImage, TInputImage>::New();

  erode->SetMarkerImage(dilate->GetOutput());
  erode->SetMaskImage(this->GetInput());
  erode->SetFullyConnected(m_FullyConnected);

  if (m_PreserveIntensities)
  {
    progress->RegisterInternalFilter(erode, .25);
    erode->Update();
    auto tempImage = TInputImage::New();
    tempImage->SetRegions(dilate->GetOutput()->GetBufferedRegion());
    tempImage->CopyInformation(this->GetInput());

    tempImage->Allocate();

    ImageRegionConstIterator<TInputImage> inputIt(this->GetInput(), dilate->GetOutput()->GetBufferedRegion());
    ImageRegionConstIterator<TInputImage> dilateIt(dilate->GetOutput(), erode->GetOutput()->GetBufferedRegion());
    ImageRegionConstIterator<TInputImage> erodeIt(erode->GetOutput(), erode->GetOutput()->GetBufferedRegion());
    ImageRegionIterator<TInputImage>      tempIt(tempImage, dilate->GetOutput()->GetBufferedRegion());
    while (!dilateIt.IsAtEnd())
    {
      if (dilateIt.Get() == erodeIt.Get())
      {
        tempIt.Set(inputIt.Get());
      }
      else
      {
        tempIt.Set(NumericTraits<InputImagePixelType>::max());
      }
      ++dilateIt;
      ++erodeIt;
      ++tempIt;
      ++inputIt;
    }

    typename ReconstructionByErosionImageFilter<TInputImage, TInputImage>::Pointer erodeAgain =
      ReconstructionByErosionImageFilter<TInputImage, TInputImage>::New();
    erodeAgain->SetMaskImage(this->GetInput());
    erodeAgain->SetMarkerImage(tempImage);
    erodeAgain->SetFullyConnected(m_FullyConnected);
    erodeAgain->GraftOutput(this->GetOutput());
    progress->RegisterInternalFilter(erodeAgain, 0.25f);
    erodeAgain->Update();
    this->GraftOutput(erodeAgain->GetOutput());
  }
  else
  {
    progress->RegisterInternalFilter(erode, .5);
    erode->GraftOutput(this->GetOutput());
    erode->Update();
    this->GraftOutput(erode->GetOutput());
  }
}

template <typename TInputImage, typename TOutputImage, typename TKernel>
void
ClosingByReconstructionImageFilter<TInputImage, TOutputImage, TKernel>::PrintSelf(std::ostream & os,
                                                                                  Indent         indent) const
{
  Superclass::PrintSelf(os, indent);

  os << indent << "Kernel: " << m_Kernel << std::endl;
  os << indent << "FullyConnected: " << (m_FullyConnected ? "On" : "Off") << std::endl;
  os << indent << "PreserveIntensities: " << m_PreserveIntensities << std::endl;
}
} // end namespace itk
#endif
