// =========================================================================
// @author Leonardo Florez Valencia
// @email florez-l@javeriana.edu.co
// =========================================================================

#include <itkImage.h>
#include <itkImageFileReader.h>
#include <itkImageFileWriter.h>
#include <fpa/Filters/Image/RandomWalker.h>
#include <fpa/Functors/Dijkstra/Image/Gaussian.h>

// -------------------------------------------------------------------------
const unsigned int Dim = 2;
typedef unsigned char TInputPixel;
typedef unsigned char TInputLabel;
typedef float         TOutputPixel;
typedef itk::Image< TInputPixel, Dim >  TInputImage;
typedef itk::Image< TInputLabel, Dim >  TInputLabelImage;
typedef itk::Image< TOutputPixel, Dim > TOutputImage;

// -------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
  // Get arguments
  if( argc < 7 )
  {
    std::cerr
      << "Usage: " << argv[ 0 ]
      << " input_image input_labels output_image output_costs alpha beta"
      << std::endl;
    return( 1 );

  } // fi
  std::string input_image_filename = argv[ 1 ];
  std::string input_labels_filename = argv[ 2 ];
  std::string output_image_filename = argv[ 3 ];
  std::string output_costs_filename = argv[ 4 ];
  double alpha = std::atof( argv[ 5 ] );
  double beta = std::atof( argv[ 6 ] );

  // Read image
  typedef itk::ImageFileReader< TInputImage > TInputImageReader;
  TInputImageReader::Pointer input_image_reader = TInputImageReader::New( );
  input_image_reader->SetFileName( input_image_filename );

  // Read labels
  typedef itk::ImageFileReader< TInputLabelImage > TInputLabelImageReader;
  TInputLabelImageReader::Pointer input_labels_reader =
    TInputLabelImageReader::New( );
  input_labels_reader->SetFileName( input_labels_filename );

  // Prepare weight functor
  typedef fpa::Functors::Dijkstra::Image::Gaussian< TInputImage, TOutputPixel > TWeight;
  TWeight::Pointer weight = TWeight::New( );
  weight->SetAlpha( alpha );
  weight->SetBeta( beta );

  // Prepare filter
  typedef fpa::Filters::Image::RandomWalker< TInputImage, TInputLabelImage, TOutputImage > TFilter;
  TFilter::Pointer filter = TFilter::New( );
  filter->SetInputImage( input_image_reader->GetOutput( ) );
  filter->SetInputLabels( input_labels_reader->GetOutput( ) );
  filter->SetWeightFunction( weight );

  // Execute filter
  filter->Update( );

  // Save results
  typedef itk::ImageFileWriter< TFilter::TOutputLabels > TOutputWriter;
  TOutputWriter::Pointer output_writer = TOutputWriter::New( );
  output_writer->SetInput( filter->GetOutputLabels( ) );
  output_writer->SetFileName( output_image_filename );

  typedef itk::ImageFileWriter< TFilter::TCostsImage > TCostsWriter;
  TCostsWriter::Pointer costs_writer = TCostsWriter::New( );
  costs_writer->SetInput( filter->GetOutputCosts( ) );
  costs_writer->SetFileName( output_costs_filename );

  try
  {
    output_writer->Update( );
    costs_writer->Update( );
  }
  catch( std::exception& err )
  {
    std::cerr << "Error caught: " << err.what( ) << std::endl;
    return( 1 );

  } // yrt

  return( 0 );
}

// eof - $RCSfile$