#include <iostream>
#include "itkVector.h"
#include "itkImage.h"
#include "itkImageFileReader.h"
#include "itkImageFileWriter.h"
#include "itkImageLinearConstIteratorWithIndex.h"
#include "itkImageLinearIteratorWithIndex.h"


int itkVectorImageReadWriteTest(int argc, char * argv [])
{

  if ( argc < 2 )
    {
    itkGenericOutputMacro(<<"Need a file to process");
    return EXIT_FAILURE;
    }

  // Test for vector pixel type.
  
  const unsigned int Dimension = 2;
  
  // Create image of vector pixels
  typedef itk::Vector< double, 4 >          PixelType;
  typedef itk::Image < PixelType, Dimension>        ImageType;
  typedef itk::ImageFileReader< ImageType > ReaderType;
  typedef itk::ImageFileWriter< ImageType > WriterType;
  
  ImageType::Pointer   inputImage  = ImageType::New();
  ReaderType::Pointer  reader      = ReaderType::New();
  WriterType::Pointer  writer      = WriterType::New();

  // In this test, we will create a 9x9 image of vectors with pixels (4,4) 
  // and (1,6) set to 'vector1'. We will filter it using 
  // RecursiveGaussianImageFilter and compare a few filtered pixels.
  // 
  //Create ON and OFF vectors
  PixelType vector0(0.0);
  PixelType vector1;
  vector1[0] = 1.0; 
  vector1[1] =  2.0; 
  vector1[2] =  3.0; 
  vector1[3] =  4.0; 
   
  typedef itk::ImageLinearIteratorWithIndex< ImageType >      IteratorType;
  typedef itk::ImageLinearConstIteratorWithIndex< ImageType > ConstIteratorType;
  
  //Create the 9x9 input image
  ImageType::SizeType size;
  size.Fill( 9 );
  ImageType::IndexType index;
  index.Fill( 0 );
  ImageType::RegionType region;
  region.SetSize( size );
  region.SetIndex( index );
  inputImage->SetLargestPossibleRegion( region );
  inputImage->SetBufferedRegion( region );
  inputImage->SetRequestedRegion( region );
  inputImage->Allocate();
  inputImage->FillBuffer( vector0);
  
  std::cout << "Create image of 9x9 image of vector pixels. IO Read and write it. " << std::endl;
  
  /* Set pixel (4,4) with the value 1 
   * and pixel (1,6) with the value 2 
   */
  index[0] = 4;
  index[1] = 4;
  inputImage->SetPixel( index, vector1);
  index[0] = 1;
  index[1] = 6;
  inputImage->SetPixel( index, vector1);

  writer->SetInput(inputImage);
  writer->SetFileName(argv[1]);
  writer->Update();

  reader->SetFileName(argv[1]);
  reader->Update();
  ImageType::Pointer outputImage = reader->GetOutput();
  
  ConstIteratorType cit( outputImage, outputImage->GetLargestPossibleRegion() );
  index[0] = 4;
  index[1] = 4;
  cit.SetIndex(index);
  if( cit.Get() != vector1 ) 
    {
    std::cout << "Vector Image Write-Read failed. Tried to write " << vector1 << 
      " But read " << cit.Get() << std::endl;
    return EXIT_FAILURE;
    }
  index[0] = 0;
  index[1] = 0;
  cit.SetIndex(index);
  if( cit.Get() != vector0 ) 
    {
    std::cout << "Vector Image Write-Read failed. Tried to write " << vector0 << 
      " But read " << cit.Get() << std::endl;
    return EXIT_FAILURE;
    }
   
  std::cout << "Image of vector pixels write-read [PASSED]" << std::endl;

  std::cout << "Test << operator:: Vector1 = " << vector1 << "[PASSED]" << std::endl;
  std::cout << "Test NumericTraits<Vector<double,4>>::Zero " << 
                        itk::NumericTraits< PixelType >::Zero << std::endl;
  std::cout << "Test NumericTraits <Vector <double,4 > >::One " << 
                        itk::NumericTraits< PixelType >::One << std::endl;
   
  return EXIT_SUCCESS; 
}

