/*=========================================================================
  Program:   vv                     http://www.creatis.insa-lyon.fr/rio/vv

  Authors belong to: 
  - University of LYON              http://www.universite-lyon.fr/
  - Léon Bérard cancer center       http://www.centreleonberard.fr
  - CREATIS CNRS laboratory         http://www.creatis.insa-lyon.fr

  This software is distributed WITHOUT ANY WARRANTY; without even
  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  PURPOSE.  See the copyright notices for more information.

  It is distributed under dual licence

  - BSD        See included LICENSE.txt file
  - CeCILL-B   http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.html
===========================================================================**/
#ifndef VVIMAGEFROMITK_H
#define VVIMAGEFROMITK_H

// vv
#include "vvImage.h"

// itk
#include <itkExtractImageFilter.h>

//------------------------------------------------------------------------------
/**Converts the itk image to vv, handling the 4D problem
 * The time_sequence boolean specifies that the image is to be interpreted as a time sequence,
 * even if its dim is < 4. */

template<unsigned int Dim, class PixelType>
static inline void ReadTimeSequence (vvImage::Pointer& vv_image, typename itk::Image<PixelType,Dim>::Pointer input, bool time_sequence=false)
{
  typedef itk::Image< PixelType, Dim > InputImageType;
  typedef itk::Image< PixelType,  Dim - 1 >    ItkImageType;
  typedef itk::ExtractImageFilter<InputImageType, ItkImageType> FilterType;

  //extract the 3D slices and put them in a std::vector<vtkImageData*>
  input->UpdateOutputInformation();
  typename InputImageType::RegionType inputRegion = input->GetLargestPossibleRegion();
  typename InputImageType::SizeType inputSize = inputRegion.GetSize();
  typename InputImageType::IndexType start = inputRegion.GetIndex();
  typename InputImageType::SizeType extractedRegionSize = inputSize;
  typename InputImageType::RegionType extractedRegion;
  extractedRegionSize[Dim - 1] = 0;
  extractedRegion.SetSize(extractedRegionSize);

  for (unsigned int i = 0; i < inputSize[Dim - 1]; i++) {
    start[Dim - 1] = i;
    extractedRegion.SetIndex(start);

    typename FilterType::Pointer filter = FilterType::New();
    filter->SetDirectionCollapseToSubmatrix();
    filter->SetExtractionRegion(extractedRegion);
    filter->SetInput(input);
    filter->ReleaseDataFlagOn();
    vv_image->AddItkImage<ItkImageType>(filter->GetOutput());
    vv_image->ComputeScalarRangeBase<PixelType, Dim-1>(filter->GetOutput());
  }
  vv_image->SetTimeSpacing(input->GetSpacing()[Dim-1]);
  vv_image->SetTimeOrigin(input->GetOrigin()[Dim-1]);
}

template<unsigned int Dim, class PixelType>
struct vvImageFromITK_Impl
{
  static vvImage::Pointer Do (typename itk::Image<PixelType,Dim>::Pointer input, bool time_sequence=false)
  {
    vvImage::Pointer vv_image=vvImage::New();
    typedef itk::Image< PixelType, Dim > InputImageType;

    if (time_sequence) //The time sequence case: create a series of VTK images
      ReadTimeSequence<Dim,PixelType>(vv_image, input, time_sequence);
    else { //Dim == 1,2,3 and not time_sequence
      vv_image->AddItkImage<InputImageType>(input);
      vv_image->ComputeScalarRangeBase<PixelType, Dim>(input);
    }
    return vv_image;
  }
};

template<class PixelType>
struct vvImageFromITK_Impl<4u, PixelType>
{
  static vvImage::Pointer Do (typename itk::Image<PixelType,4u>::Pointer input, bool time_sequence=false)
  {
    vvImage::Pointer vv_image = vvImage::New();
    ReadTimeSequence<4u,PixelType>(vv_image, input, time_sequence);
    return vv_image;
  }
};

template<unsigned int Dim, class PixelType> vvImage::Pointer vvImageFromITK(typename itk::Image<PixelType,Dim>::Pointer input, bool time_sequence=false)
{
    assert(Dim < 5 && Dim > 0); // We don't handle anything higher than 4-dimensional (for the moment :-p)
    return vvImageFromITK_Impl<Dim, PixelType>::Do(input, time_sequence);
}
//------------------------------------------------------------------------------

#endif //vvImageFromITK