#include <iostream>
#include <algorithm>

#include "itkImage.h"
#include "itkImageRandomNonRepeatingConstIteratorWithIndex.h"

int main(int, char* [])
{
  const unsigned int ImageDimension = 2;
  typedef itk::Index< ImageDimension >             PixelType;
  typedef itk::Image< PixelType, ImageDimension >  ImageType;
  typedef itk::ImageRandomNonRepeatingConstIteratorWithIndex< ImageType > RandomConstIteratorType;

  const unsigned long N = 10;
  const int Seed = 42;

  ImageType::SizeType size;
  size.Fill(N);
  ImageType::IndexType start;
  start.Fill(0);

  ImageType::RegionType region;
  region.SetIndex( start );
  region.SetSize( size );

  ImageType::Pointer myImage = ImageType::New();
  myImage->SetLargestPossibleRegion( region );
  myImage->SetBufferedRegion( region );
  myImage->SetRequestedRegion( region );
  myImage->Allocate();

  typedef std::vector<ImageType::IndexType> WalkType;
  typedef WalkType::iterator                WalkIteratorType;
  typedef std::pair<WalkIteratorType,WalkIteratorType> WalkIteratorPairType;
  
  WalkType firstWalk(N);
  RandomConstIteratorType firstIt(myImage, region); 
  firstIt.ReinitializeSeed( Seed );
  firstIt.SetNumberOfSamples( region.GetNumberOfPixels() );
  for (firstIt.GoToBegin(); !firstIt.IsAtEnd(); ++firstIt)
    {
    firstWalk.push_back( firstIt.GetIndex() );
    }

  WalkType secondWalk(N);
  RandomConstIteratorType secondIt(myImage, region);
  secondIt.ReinitializeSeed( Seed );
  secondIt.SetNumberOfSamples( region.GetNumberOfPixels() );
  for (secondIt.GoToBegin(); !secondIt.IsAtEnd(); ++secondIt)
    {
    secondWalk.push_back( secondIt.GetIndex() );
    }

  std::pair<WalkIteratorType,WalkIteratorType> mismatchTest;
  mismatchTest = std::mismatch( firstWalk.begin(), firstWalk.end(),secondWalk.begin() );
  if ( mismatchTest.first != firstWalk.end() )
    {
    std::cerr << "Two iterations with the same seed do not walk over the same pixels" << std::endl
              << "First mismatch found after " << mismatchTest.first - firstWalk.begin() << " iterations." << std::endl
              << "First walk index  : " << *(mismatchTest.first) << std::endl
              << "Second walk index : " << *(mismatchTest.second) << std::endl;
    return EXIT_FAILURE;
    }

  std::cout << "Test passed" << std::endl;
  return EXIT_SUCCESS;
}