/*=========================================================================
 *
 *  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 itkSimpleContourExtractorImageFilter_h
#define itkSimpleContourExtractorImageFilter_h

#include "itkBoxImageFilter.h"
#include "itkImage.h"
#include "itkNumericTraits.h"

namespace itk
{
/**
 * \class SimpleContourExtractorImageFilter
 * \brief Computes an image of contours which will be the contour
 * of the first image.
 *
 * A pixel of the source image is considered to belong to the contour
 * if its pixel value is equal to the input foreground value and it
 * has in its neighborhood at least one pixel which its pixel value is
 * equal to the input background value. The output image will have
 * pixels which will be set to the output foreground value if they
 * belong to the contour, otherwise they will be set to the output
 * background value.
 *
 * The neighborhood "radius" is set thanks to the radius params.
 * \sphinx
 * \sphinxexample{Filtering/ImageFeature/ExtractContoursFromImage,Extract Contours From Image}
 * \endsphinx
 * \sa Image
 * \sa Neighborhood
 * \sa NeighborhoodOperator
 * \sa NeighborhoodIterator
 *
 * \ingroup IntensityImageFilters
 * \ingroup ITKImageFeature
 */
template <typename TInputImage, typename TOutputImage>
class ITK_TEMPLATE_EXPORT SimpleContourExtractorImageFilter : public BoxImageFilter<TInputImage, TOutputImage>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(SimpleContourExtractorImageFilter);

  /** Extract dimension from input and output image. */
  static constexpr unsigned int InputImageDimension = TInputImage::ImageDimension;
  static constexpr unsigned int OutputImageDimension = TOutputImage::ImageDimension;

  /** Convenient type alias for simplifying declarations. */
  using InputImageType = TInputImage;
  using OutputImageType = TOutputImage;

  /** Standard class type aliases. */
  using Self = SimpleContourExtractorImageFilter;
  using Superclass = BoxImageFilter<InputImageType, OutputImageType>;
  using Pointer = SmartPointer<Self>;
  using ConstPointer = SmartPointer<const Self>;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** \see LightObject::GetNameOfClass() */
  itkOverrideGetNameOfClassMacro(SimpleContourExtractorImageFilter);

  /** Image type alias support */
  using InputPixelType = typename InputImageType::PixelType;
  using OutputPixelType = typename OutputImageType::PixelType;
  using InputRealType = typename NumericTraits<InputPixelType>::RealType;

  using InputImageRegionType = typename InputImageType::RegionType;
  using OutputImageRegionType = typename OutputImageType::RegionType;

  using InputSizeType = typename InputImageType::SizeType;

  /** Set the foreground value used in order to identify a foreground
   * pixel in the input image. */
  itkSetMacro(InputForegroundValue, InputPixelType);

  /** Get the foreground value used in order to identify a foreground
   * pixel in the input image. */
  itkGetConstReferenceMacro(InputForegroundValue, InputPixelType);

  /** Set the background value used in order to identify a background
   * pixel in the input image. */
  itkSetMacro(InputBackgroundValue, InputPixelType);

  /** Get the background value used in order to identify a background
   * pixel in the input image. */
  itkGetConstReferenceMacro(InputBackgroundValue, InputPixelType);

  /** Set the foreground value used in order to identify a foreground
   * pixel in the output image. */
  itkSetMacro(OutputForegroundValue, OutputPixelType);

  /** Get the foreground value used in order to identify a foreground
   * pixel in the output image. */
  itkGetConstReferenceMacro(OutputForegroundValue, OutputPixelType);

  /** Set the background value used in order to identify a background
   * pixel in the output image. */
  itkSetMacro(OutputBackgroundValue, OutputPixelType);

  /** Get the background value used in order to identify a background
   * pixel in the output image. */
  itkGetConstReferenceMacro(OutputBackgroundValue, OutputPixelType);

  itkConceptMacro(InputHasNumericTraitsCheck, (Concept::HasNumericTraits<InputPixelType>));
  itkConceptMacro(OutputHasNumericTraitsCheck, (Concept::HasNumericTraits<OutputPixelType>));

protected:
  SimpleContourExtractorImageFilter();
  ~SimpleContourExtractorImageFilter() override = default;
  void
  PrintSelf(std::ostream & os, Indent indent) const override;

  /** SimpleContourExtractorImageFilter can be implemented as a
   *  multithreaded filter. Therefore, this implementation provides a
   *  DynamicThreadedGenerateData() routine which is called for each
   *  processing thread. The output image data is allocated
   *  automatically by the superclass prior to calling
   *  DynamicThreadedGenerateData(). DynamicThreadedGenerateData can only write to
   *  the portion of the output image specified by the parameter
   *  "outputRegionForThread"
   *
   *  \sa ImageToImageFilter::ThreadedGenerateData(),
   *      ImageToImageFilter::GenerateData()
   */
  void
  DynamicThreadedGenerateData(const OutputImageRegionType & outputRegionForThread) override;


private:
  InputPixelType  m_InputForegroundValue{};
  InputPixelType  m_InputBackgroundValue{};
  OutputPixelType m_OutputForegroundValue{};
  OutputPixelType m_OutputBackgroundValue{};
};
} // end namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#  include "itkSimpleContourExtractorImageFilter.hxx"
#endif

#endif
