/*=========================================================================
 *
 *  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 RGBToVectorImageAdaptor.
 *
 *  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 "itkRGBToVectorImageAdaptor.h"
#include "itkImageRegionIteratorWithIndex.h"

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


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

  using ComponentType = float;

  using RGBPixelType = itk::RGBPixel<ComponentType>;

  constexpr unsigned int ImageDimension{ 2 };

  using ImageType = itk::Image<RGBPixelType, ImageDimension>;

  using ImageAdaptorType = itk::RGBToVectorImageAdaptor<ImageType>;

  using IteratorType = itk::ImageRegionIteratorWithIndex<ImageType>;

  using RedIteratorType = itk::ImageRegionIteratorWithIndex<ImageAdaptorType>;

  auto size = ImageType::SizeType::Filled(2);

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

  const 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 color;
  color.SetRed(0.7);
  color.SetGreen(0.8);
  color.SetBlue(0.5);

  // Initializing all the pixel in the image
  it1.GoToBegin();
  while (!it1.IsAtEnd())
  {
    it1.Set(color);
    ++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.GetRed() << "  ";
    std::cout << c.GetGreen() << "  ";
    std::cout << c.GetBlue() << std::endl;
    ++it1;
  }

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


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

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

  using PixelVectorType = ImageAdaptorType::AccessorType::ExternalType;

  PixelVectorType vector;

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

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


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

  it1.GoToBegin();
  while (!it1.IsAtEnd())
  {
    const ImageType::PixelType c(it1.Get());
    std::cout << c.GetRed() << "  ";
    std::cout << c.GetGreen() << "  ";
    std::cout << c.GetBlue() << std::endl;
    ++it1;
  }


  return EXIT_SUCCESS;
}
