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

#include <itkImage.h>
#include <itkImageFileReader.h>
#include <itkImageFileWriter.h>
#include <fpa/Common/OriginalRandomWalker.h>
#include <fpa/Functors/Dijkstra/Image/Gaussian.h>

// -------------------------------------------------------------------------
const unsigned int Dim = 2;
typedef unsigned char TPixel;
typedef unsigned char TLabel;
typedef double        TScalar;

typedef itk::Image< TPixel, Dim > TImage;
typedef itk::Image< TLabel, Dim > TLabels;

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

  } // fi
  std::string input_image_filename, input_labels_filename;
  std::string output_labels_filename, output_probabilities_filename;
  double beta, eps;
  input_image_filename = argv[ 1 ];
  input_labels_filename = argv[ 2 ];
  output_labels_filename = argv[ 3 ];
  output_probabilities_filename = argv[ 4 ];
  beta = std::atof( argv[ 5 ] );
  eps = std::atof( argv[ 6 ] );

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

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

  // Random walker function
  typedef fpa::Functors::Dijkstra::Image::Gaussian< TImage, TScalar > TFunction;
  TFunction::Pointer edge = TFunction::New( );
  edge->SetBeta( beta );
  edge->SetEpsilon( eps );
  edge->TreatAsWeightOff( );

  // Random walker
  typedef fpa::Common::OriginalRandomWalker< TImage, TLabels, TScalar > TFilter;
  TFilter::Pointer rw = TFilter::New( );
  rw->SetInput( input_image_reader->GetOutput( ) );
  rw->SetInputLabels( input_labels_reader->GetOutput( ) );
  rw->SetEdgeFunction( edge );

  // Save labels
  typedef itk::ImageFileWriter< TFilter::TLabels > TLabelsWriter;
  TLabelsWriter::Pointer output_labels_writer = TLabelsWriter::New( );
  output_labels_writer->SetFileName( output_labels_filename );
  output_labels_writer->SetInput( rw->GetOutput( ) );

  // Save probabilities
  typedef itk::ImageFileWriter< TFilter::TScalarImage > TProbabilitesWriter;
  TProbabilitesWriter::Pointer output_probabilities_writer =
    TProbabilitesWriter::New( );
  output_probabilities_writer->SetFileName( output_probabilities_filename );
  output_probabilities_writer->SetInput( rw->GetOutputProbabilities( ) );

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

  } // yrt
  return( 0 );
}

// eof - $RCSfile$