/*=========================================================================
 *
 *  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.
 *
 *=========================================================================*/

/**
 *
 *  This program tests the VectorToRGBImageAdaptor.
 *
 *  This class allows to take an image of pixel type RGBPixel,
 *  and use it as if it was an image of pixel type itk::Vector<>.
 *
 */


#include "itkVectorToRGBImageAdaptor.h"
#include "itkImageRegionIteratorWithIndex.h"

//-------------------------
//
//   Main code
//
//-------------------------
int
itkVectorToRGBImageAdaptorTest(int, char *[])
{


  //-------------------------------------
  //     Typedefs for convenience
  //-------------------------------------

  using ValueType = float;

  constexpr unsigned int numberOfComponents = 3;

  using VectorPixelType = itk::Vector<ValueType, numberOfComponents>;

  constexpr unsigned int ImageDimension = 2;

  using ImageType = itk::Image<VectorPixelType, ImageDimension>;
  using ImageAdaptorType = itk::VectorToRGBImageAdaptor<ImageType>;
  using IteratorType = itk::ImageRegionIteratorWithIndex<ImageType>;
  using RGBIteratorType = itk::ImageRegionIteratorWithIndex<ImageAdaptorType>;

  ImageType::SizeType size;
  size[0] = 2;
  size[1] = 2;

  ImageType::IndexType index;
  index[0] = 0;
  index[1] = 0;

  ImageType::RegionType region{ index, size };

  auto image = ImageType::New();


  image->SetRegions(region);
  image->Allocate();

  IteratorType it1(image, image->GetRequestedRegion());

  // Value to initialize the pixels
  ImageType::PixelType vector;
  vector[0] = 1.2;
  vector[1] = 1.3;
  vector[2] = 1.4;

  // Initializing all the pixel in the image
  it1.GoToBegin();
  while (!it1.IsAtEnd())
  {
    it1.Set(vector);
    ++it1;
  }

  // Reading the values to verify the image content
  std::cout << "--- Before --- " << std::endl;
  it1.GoToBegin();
  while (!it1.IsAtEnd())
  {
    const ImageType::PixelType c(it1.Get());
    std::cout << c[0] << "  ";
    std::cout << c[1] << "  ";
    std::cout << c[2] << std::endl;
    ++it1;
  }

  auto adaptor = ImageAdaptorType::New();
  adaptor->SetImage(image);


  RGBIteratorType it2(adaptor, adaptor->GetRequestedRegion());

  // Set the values of the image, using the adaptor

  using RGBPixelType = ImageAdaptorType::AccessorType::ExternalType;

  RGBPixelType color;

  color[0] = 13;
  color[1] = 17;
  color[2] = 19;

  it2.GoToBegin();
  while (!it2.IsAtEnd())
  {
    it2.Set(color);
    ++it2;
  }


  std::cout << "--- After --- " << std::endl;

  it1.GoToBegin();
  while (!it1.IsAtEnd())
  {
    const ImageType::PixelType c(it1.Get());
    std::cout << c[0] << "  ";
    std::cout << c[1] << "  ";
    std::cout << c[2] << std::endl;
    ++it1;
  }


  return EXIT_SUCCESS;
}
