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

#include "itkJoinImageFilter.h"
#include "itkRGBAPixel.h"
#include "itkImageRegionIterator.h"
#include "itkTestingMacros.h"
#include <algorithm> // For generate.
#include <random>    // For mt19937.

int
itkJoinImageFilterTest(int, char *[])
{
  // Define the dimension of the images
  constexpr unsigned int myDimension{ 2 };

  // Declare the types of the images
  using myImageType1 = itk::Image<signed char, myDimension>;
  using myImageType2 = itk::Image<itk::Vector<unsigned short, 2>, myDimension>;
  using myImageType3 = itk::Image<itk::RGBAPixel<short>, myDimension>;

  // Declare the type of the size
  using mySizeType = itk::Size<myDimension>;

  // Declare the type of the Region
  using myRegionType = itk::ImageRegion<myDimension>;

  // Create three images
  auto inputImageA = myImageType1::New();
  auto inputImageB = myImageType2::New();
  auto inputImageC = myImageType3::New();

  // Define their size and region
  mySizeType size{ 5, 8 };

  const myRegionType region{ size };

  // Initialize Image A
  inputImageA->SetRegions(region);
  inputImageA->Allocate();

  // Initialize Image B
  inputImageB->SetRegions(region);
  inputImageB->Allocate();

  // Initialize Image C
  inputImageC->SetRegions(region);
  inputImageC->Allocate();

  // Declare Iterator types appropriate for each image
  using myIteratorType1 = itk::ImageRegionIterator<myImageType1>;
  using myIteratorType2 = itk::ImageRegionIterator<myImageType2>;
  using myIteratorType3 = itk::ImageRegionIterator<myImageType3>;

  std::mt19937 randomNumberEngine{};

  std::uniform_int_distribution<> randomNumberDistribution1(std::numeric_limits<myImageType1::PixelType>::min(),
                                                            std::numeric_limits<myImageType1::PixelType>::max());

  // Create one iterator for Image A (this is a light object)
  myIteratorType1 it1(inputImageA, region);

  // Initialize the content of Image A
  std::cout << "Image #1 " << std::endl;
  while (!it1.IsAtEnd())
  {
    it1.Set(static_cast<myImageType1::PixelType>(randomNumberDistribution1(randomNumberEngine)));
    std::cout << static_cast<int>(it1.Get()) << std::endl;
    ++it1;
  }

  std::uniform_int_distribution<unsigned short> randomNumberDistribution2(0, 32765);

  // Create one iterator for Image B (this is a light object)
  myIteratorType2 it2(inputImageB, region);

  // Initialize the content of Image B
  std::cout << std::endl;
  std::cout << "Image #2 " << std::endl;
  itk::Vector<unsigned short, 2> vec;
  while (!it2.IsAtEnd())
  {
    std::generate(vec.begin(), vec.end(), [&randomNumberEngine, &randomNumberDistribution2] {
      return randomNumberDistribution2(randomNumberEngine);
    });
    it2.Set(vec);
    std::cout << it2.Get() << std::endl;
    ++it2;
  }

  std::uniform_int_distribution<short> randomNumberDistribution3(0, 255);

  // Create one iterator for Image C (this is a light object)
  myIteratorType3 itRGBA(inputImageC, region);

  // Initialize the content of Image C
  std::cout << std::endl;
  std::cout << "Image #3 " << std::endl;
  itk::RGBAPixel<short> rgbaVec;
  while (!itRGBA.IsAtEnd())
  {
    std::generate(rgbaVec.begin(), rgbaVec.end(), [&randomNumberEngine, &randomNumberDistribution3] {
      return randomNumberDistribution3(randomNumberEngine);
    });
    itRGBA.Set(rgbaVec);
    //  std::cout << itRGBA.Get() << std::endl;
    ++itRGBA;
  }

  // Declare the types for the Join Filters
  using myFilterType = itk::JoinImageFilter<myImageType1, myImageType2>;
  using myFilterType1 = itk::JoinImageFilter<myImageType2, myImageType1>;
  using myFilterType2 = itk::JoinImageFilter<myImageType1, myImageType1>;
  using myFilterType3 = itk::JoinImageFilter<myFilterType::OutputImageType, myImageType3>;
  using myFilterType4 = itk::JoinImageFilter<myImageType2, myImageType2>;

  using myOutputIteratorType = itk::ImageRegionIterator<myFilterType::OutputImageType>;
  using myOutputIteratorType1 = itk::ImageRegionIterator<myFilterType1::OutputImageType>;
  using myOutputIteratorType2 = itk::ImageRegionIterator<myFilterType2::OutputImageType>;
  using myOutputIteratorType3 = itk::ImageRegionIterator<myFilterType3::OutputImageType>;
  using myOutputIteratorType4 = itk::ImageRegionIterator<myFilterType4::OutputImageType>;


  //
  // Join image #1 and #2
  //

  // Setup a JoinImageFilter
  auto filter = myFilterType::New();

  ITK_EXERCISE_BASIC_OBJECT_METHODS(filter, JoinImageFilter, BinaryGeneratorImageFilter);


  filter->SetInput1(inputImageA);
  filter->SetInput2(inputImageB);

  //
  // Join image #1#2 and #3
  //

  // Setup a JoinImageFilter
  auto filter123 = myFilterType3::New();
  filter123->SetInput1(filter->GetOutput());
  filter123->SetInput2(inputImageC);
  filter123->Update(); // This Update will force filter to execute, then filter123

  // Create an iterator for going through the image #1#2
  const myFilterType::OutputImageType::Pointer outputImage = filter->GetOutput();
  myOutputIteratorType                         it3(outputImage, outputImage->GetRequestedRegion());

  // Print the content of the result image
  std::cout << std::endl;
  std::cout << "Joining #1 and #2 image " << std::endl;
  while (!it3.IsAtEnd())
  {
    std::cout << it3.Get() << std::endl;
    ++it3;
  }

  // Create an iterator for going through the image #1#2#3
  const myFilterType3::OutputImageType::Pointer outputImage123 = filter123->GetOutput();
  myOutputIteratorType3                         it123(outputImage123, outputImage123->GetRequestedRegion());

  // Print the content of the result image
  std::cout << std::endl;
  std::cout << "Joining #1#2 and #3 image " << std::endl;
  while (!it123.IsAtEnd())
  {
    std::cout << it123.Get() << std::endl;
    ++it123;
  }

  //
  // Join image #2 and #1
  //

  // Setup a JoinImageFilter
  auto filter1 = myFilterType1::New();
  filter1->SetInput1(inputImageB);
  filter1->SetInput2(inputImageA);
  filter1->Update();

  // Create an iterator for going through the image output
  const myFilterType1::OutputImageType::Pointer outputImage1 = filter1->GetOutput();
  myOutputIteratorType1                         it4(outputImage1, outputImage1->GetRequestedRegion());

  // Print the content of the result image
  std::cout << std::endl;
  std::cout << "Joining #2 and #1 image " << std::endl;
  while (!it4.IsAtEnd())
  {
    std::cout << it4.Get() << std::endl;
    ++it4;
  }

  //
  // Join image #1 and #1
  //

  // Setup a JoinImageFilter
  auto filter2 = myFilterType2::New();
  filter2->SetInput1(inputImageA);
  filter2->SetInput2(inputImageA);
  filter2->Update();

  // Create an iterator for going through the image output
  const myFilterType2::OutputImageType::Pointer outputImage2 = filter2->GetOutput();
  myOutputIteratorType2                         it5(outputImage2, outputImage2->GetRequestedRegion());

  // Print the content of the result image
  std::cout << "Joining #1 and #1 image " << std::endl;
  while (!it5.IsAtEnd())
  {
    std::cout << static_cast<int>(it5.Get()[0]) << "  " << static_cast<int>(it5.Get()[1]) << std::endl;
    ++it5;
  }

  //
  // Join image #2 and #2
  //

  // Setup a JoinImageFilter
  auto filter4 = myFilterType4::New();
  filter4->SetInput1(inputImageB);
  filter4->SetInput2(inputImageB);
  filter4->Update();

  // Create an iterator for going through the image output
  const myFilterType4::OutputImageType::Pointer outputImage4 = filter4->GetOutput();
  myOutputIteratorType4                         it6(outputImage4, outputImage4->GetRequestedRegion());

  // Print the content of the result image
  std::cout << "Joining #2 and #2 image " << std::endl;
  while (!it6.IsAtEnd())
  {
    std::cout << it6.Get() << std::endl;
    ++it6;
  }


  std::cout << "Test finished." << std::endl;
  return EXIT_SUCCESS;
}
