// =========================================================================
// @author Leonardo Florez-Valencia (florez-l@javeriana.edu.co)
// =========================================================================
#ifndef __RandomWalkerLabelling__hxx__
#define __RandomWalkerLabelling__hxx__

#include <limits>

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
void RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
SetInputImage( const TRawImage* i )
{
  this->SetInput( i );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
typename RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
TLabelsImage* RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
GetOutputLabels( )
{
  return( this->GetOutput( ) );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
const typename RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
TLabelsImage* RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
GetOutputLabels( ) const
{
  return( this->GetOutput( ) );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
typename RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
TLabel RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
GetOutsideLabel( ) const
{
  return( this->GetInitValue( ) );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
void RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
SetOutsideLabel( const TLabel& v )
{
  this->SetInitValue( v );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
RandomWalkLabelling( )
  : Superclass( ),
    m_InsideLabel( TLabel( 1 ) ),
    m_LowerLabel( TLabel( 3 ) ),
    m_UpperLabel( TLabel( 4 ) ),
    m_Radius( double( 1 ) ),
    m_LowerThreshold( double( 0 ) ),
    m_UpperThreshold( double( 0 ) ),
    m_MaxCost( std::numeric_limits< TScalar >::max( ) )
{
  fpaFilterInputConfigureMacro( InputCosts, TCostsImage );
  fpaFilterInputConfigureMacro( InputPath, TPath );
  this->SetOutsideLabel( TLabel( 2 ) );
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
~RandomWalkLabelling( )
{
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
void RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
_PrepareSeeds( const itk::DataObject* reference )
{
  const TPath* path = this->GetInputPath( );
  if( path->GetSize( ) > 0 )
  {
    TNode node;
    node.Vertex = node.Parent = path->GetVertex( 0 );
    node.FrontId = 1;
    this->m_UnifiedSeeds.clear( );
    this->m_UnifiedSeeds.insert( node );
    this->m_CurrIdx = 0;

  } // fi
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
void RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
_PostComputeOutputValue( TNode& n )
{
  const TRawImage* raw = this->GetInput( );
  const TCostsImage* costs = this->GetInputCosts( );
  const TPath* path = this->GetInputPath( );

  TPoint c, p;
  raw->TransformIndexToPhysicalPoint( path->GetVertex( this->m_CurrIdx ), c );
  raw->TransformIndexToPhysicalPoint( n.Vertex, p );
  double d = double( c.EuclideanDistanceTo( p ) );
  if( d <= this->m_Radius )
  {
    n.FrontId = 1;
    if( costs->GetPixel( n.Vertex ) == this->m_MaxCost )
    {
      double v = double( raw->GetPixel( n.Vertex ) );
      if( v <= this->m_LowerThreshold )
        n.Value = this->GetLowerLabel( );
      else if( v >= this->m_UpperThreshold )
        n.Value = this->GetUpperLabel( );
      else
        n.Value = TLabel( 0 );
    }
    else
      n.Value = this->GetInsideLabel( );
  }
  else
  {
    n.Value = this->GetOutsideLabel( );
    n.FrontId = 0;

  } // fi
}

// -------------------------------------------------------------------------
template< class _TRawImage, class _TCostsImage, class _TLabelsImage >
void RandomWalkLabelling< _TRawImage, _TCostsImage, _TLabelsImage >::
_Reinitialize( )
{
  const TPath* path = this->GetInputPath( );
  while(
    this->_GetMark( path->GetVertex( this->m_CurrIdx ) ) > 0 &&
    this->m_CurrIdx < path->GetSize( )
    )
    this->m_CurrIdx += 1;
  if( this->m_CurrIdx < path->GetSize( ) )
  {
    TNode node;
    node.Vertex = node.Parent = path->GetVertex( this->m_CurrIdx );
    node.FrontId = 1;
    this->_QueuePush( node );

  } // fi
}

#endif // __RandomWalkLabelling__hxx__

// eof - $RCSfile$