/*=========================================================================
 *
 *  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 itkImageToPathFilter_h
#define itkImageToPathFilter_h

#include "itkImage.h"
#include "itkPathSource.h"

namespace itk
{
/**
 * \class ImageToPathFilter
 * \brief Base class for filters that take an image as input and produce an path as output.
 *
 * ImageToPathFilter is the base class for all process objects that output
 * path data and require image data as input. Specifically, this class
 * defines the SetInput() method for defining the input to a filter.
 *
 * This code was contributed in the Insight Journal paper:
 * "ContourExtractor2DImageFilter: A subpixel-precision image isocontour extraction filter."
 * by Pincus Z.
 * https://www.insight-journal.org/browse/publication/72
 *
 * \ingroup ImageFilters
 * \ingroup ITKPath
 */
template <typename TInputImage, typename TOutputPath>
class ITK_TEMPLATE_EXPORT ImageToPathFilter : public PathSource<TOutputPath>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(ImageToPathFilter);

  /** Standard class type aliases. */
  using Self = ImageToPathFilter;
  using Superclass = PathSource<TOutputPath>;
  using Pointer = SmartPointer<Self>;
  using ConstPointer = SmartPointer<const Self>;

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

  /** Some convenient type alias. */
  using InputImageType = TInputImage;
  using InputImagePointer = typename InputImageType::Pointer;
  using InputImageConstPointer = typename InputImageType::ConstPointer;
  using InputImageRegionType = typename InputImageType::RegionType;
  using InputImagePixelType = typename InputImageType::PixelType;

  /** ImageDimension constants */
  static constexpr unsigned int InputImageDimension = TInputImage::ImageDimension;

  /** Set/Get the image input of this process object.  */
  using Superclass::SetInput;
  virtual void
  SetInput(const InputImageType * input);

  virtual void
  SetInput(unsigned int, const TInputImage * image);

  const InputImageType *
  GetInput();

  const InputImageType *
  GetInput(unsigned int idx);

protected:
  ImageToPathFilter();
  ~ImageToPathFilter() override = default;

  void
  PrintSelf(std::ostream & os, Indent indent) const override;
};
} // end namespace itk

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

#endif
