/* Computes the gradient magnitude using finite differences localy */

#include "vvITKFilterModule.h"

#include "itkGradientMagnitudeImageFilter.h"


template <class InputPixelType>
class GradientMagnitudeRunner
  {
  public:
      typedef  InputPixelType                       PixelType;
      typedef  itk::Image< PixelType, 3 >           ImageType; 
      
      typedef  itk::GradientMagnitudeImageFilter< ImageType,  
                                                  ImageType >    FilterType;

      typedef  VolView::PlugIn::FilterModule< FilterType >       ModuleType;

  public:
    GradientMagnitudeRunner() {}
    void Execute( vtkVVPluginInfo *info, vtkVVProcessDataStruct *pds )
    {
      ModuleType  module;
      module.SetPluginInfo( info );
      module.SetUpdateMessage("Computing the gradient magnitude...");
      // Execute the filter
      module.ProcessData( pds  );
    }
  };




static int ProcessData(void *inf, vtkVVProcessDataStruct *pds)
{

  vtkVVPluginInfo *info = (vtkVVPluginInfo *)inf;

  const unsigned int Dimension = 3;

  try 
  {
  switch( info->InputVolumeScalarType )
    {
    case VTK_CHAR:
      {
      GradientMagnitudeRunner<signed char> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_UNSIGNED_CHAR:
      {
      GradientMagnitudeRunner<unsigned char> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_SHORT:
      {
      GradientMagnitudeRunner<signed short> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_UNSIGNED_SHORT:
      {
      GradientMagnitudeRunner<unsigned short> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_INT:
      {
      GradientMagnitudeRunner<signed int> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_UNSIGNED_INT:
      {
      GradientMagnitudeRunner<unsigned int> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_LONG:
      {
      GradientMagnitudeRunner<signed long> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_UNSIGNED_LONG:
      {
      GradientMagnitudeRunner<unsigned long> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_FLOAT:
      {
      GradientMagnitudeRunner<float> runner;
      runner.Execute( info, pds );
      break; 
      }
    case VTK_DOUBLE:
      {
      GradientMagnitudeRunner<double> runner;
      runner.Execute( info, pds );
      break; 
      }
    }
  }
  catch( itk::ExceptionObject & except )
  {
    info->SetProperty( info, VVP_ERROR, except.what() ); 
    return -1;
  }
  return 0;
}


static int UpdateGUI(void *inf)
{
  vtkVVPluginInfo *info = (vtkVVPluginInfo *)inf;

  info->SetProperty(info, VVP_REQUIRED_Z_OVERLAP, "0");
  
  info->OutputVolumeScalarType = info->InputVolumeScalarType;
  info->OutputVolumeNumberOfComponents = 
    info->InputVolumeNumberOfComponents;
  memcpy(info->OutputVolumeDimensions,info->InputVolumeDimensions,
         3*sizeof(int));
  memcpy(info->OutputVolumeSpacing,info->InputVolumeSpacing,
         3*sizeof(float));
  memcpy(info->OutputVolumeOrigin,info->InputVolumeOrigin,
         3*sizeof(float));

  // if multi component we have 1 scalar for input and 1 scalar for output
  if (info->InputVolumeNumberOfComponents > 1)
    {
    int sizeReq = 2*info->InputVolumeScalarSize;
    char tmps[500];
    sprintf(tmps,"%i",sizeReq);
    info->SetProperty(info, VVP_PER_VOXEL_MEMORY_REQUIRED, tmps); 
    }
  else
    {
    // otherwise no memory is required
    info->SetProperty(info, VVP_PER_VOXEL_MEMORY_REQUIRED, "0"); 
    }
  
  return 1;
}


extern "C" {
  
void VV_PLUGIN_EXPORT vvITKGradientMagnitudeInit(vtkVVPluginInfo *info)
{
  vvPluginVersionCheck();

  // setup information that never changes
  info->ProcessData = ProcessData;
  info->UpdateGUI = UpdateGUI;
  info->SetProperty(info, VVP_NAME, "Gradient Magnitude (ITK)");
  info->SetProperty(info, VVP_GROUP, "Utility");
  info->SetProperty(info, VVP_TERSE_DOCUMENTATION,
                                "Gradient Magnitude");
  info->SetProperty(info, VVP_FULL_DOCUMENTATION,
    "This filter computes the magnitude if the gradient using finite differences. Basically by convolving with masks of type [-1,0,1].");
  info->SetProperty(info, VVP_SUPPORTS_IN_PLACE_PROCESSING, "0");
  info->SetProperty(info, VVP_SUPPORTS_PROCESSING_PIECES,   "0");
  info->SetProperty(info, VVP_NUMBER_OF_GUI_ITEMS,          "0");
  info->SetProperty(info, VVP_REQUIRED_Z_OVERLAP,           "0");
  info->SetProperty(info, VVP_PER_VOXEL_MEMORY_REQUIRED,    "0"); 
}

}
