#ifndef __FPA__VTK__IMAGE3DOBSERVER__HXX__
#define __FPA__VTK__IMAGE3DOBSERVER__HXX__

#include <itkImageBase.h>

#include <vtkCellArray.h>
#include <vtkFloatArray.h>
#include <vtkPointData.h>
#include <vtkPoints.h>
#include <vtkRenderer.h>
#include <vtkRendererCollection.h>

/*
  #include <vtkCellArray.h>
  #include <vtkProperty.h>
*/

// -------------------------------------------------------------------------
template< class F, class R >
void fpa::VTK::Image3DObserver< F, R >::
SetRenderWindow( R* rw )
{
  this->m_RenderWindow = rw;
}

// -------------------------------------------------------------------------
template< class F, class R >
void fpa::VTK::Image3DObserver< F, R >::
Execute( const itk::Object* c, const itk::EventObject& e )
{
  typedef itk::ImageBase< 3 >               _TImage;
  typedef typename F::TEvent                _TEvent;
  typedef typename F::TFrontEvent           _TFrontEvent;
  typedef typename F::TMarkEvent            _TMarkEvent;
  typedef typename F::TCollisionEvent       _TCollisionEvent;
  typedef typename F::TEndEvent             _TEndEvent;
  typedef typename F::TBacktrackingEvent    _TBacktrackingEvent;
  typedef typename F::TEndBacktrackingEvent _TEndBacktrackingEvent;

  // Check inputs
  if( this->m_RenderWindow == NULL )
    return;
  vtkRenderer* ren =
    this->m_RenderWindow->GetRenderers( )->GetFirstRenderer( );
  if( ren == NULL )
    return;
  const F* filter = dynamic_cast< const F* >( c );
  if( filter == NULL )
    return;
  const _TImage* image = filter->GetInput( );
  if( image == NULL )
    return;

  // Create actor
  _TImage::RegionType reg = image->GetLargestPossibleRegion( );
  _TImage::SizeType siz = reg.GetSize( );
  if( this->m_Data.GetPointer( ) == NULL )
  {
    this->m_Data   = vtkSmartPointer< vtkPolyData >::New( );
    this->m_Mapper = vtkSmartPointer< vtkPolyDataMapper >::New( );
    this->m_Actor  = vtkSmartPointer< vtkActor >::New( );

    vtkSmartPointer< vtkPoints > points =
      vtkSmartPointer< vtkPoints >::New( );
    vtkSmartPointer< vtkCellArray > vertices =
      vtkSmartPointer< vtkCellArray >::New( );
    vtkSmartPointer< vtkFloatArray > scalars =
      vtkSmartPointer< vtkFloatArray >::New( );
    this->m_Data->SetPoints( points );
    this->m_Data->SetVerts( vertices );
    this->m_Data->GetPointData( )->SetScalars( scalars );

    this->m_Mapper->SetInputData( this->m_Data );
    this->m_Actor->SetMapper( this->m_Mapper );
    ren->AddActor( this->m_Actor );

    this->m_Marks = TMarks::New( );
    this->m_Marks->SetLargestPossibleRegion(
      image->GetLargestPossibleRegion( )
      );
    this->m_Marks->SetRequestedRegion( image->GetRequestedRegion( ) );
    this->m_Marks->SetBufferedRegion( image->GetBufferedRegion( ) );
    this->m_Marks->SetOrigin( image->GetOrigin( ) );
    this->m_Marks->SetSpacing( image->GetSpacing( ) );
    this->m_Marks->SetDirection( image->GetDirection( ) );
    this->m_Marks->Allocate( );
    this->m_Marks->FillBuffer( -1 );
    this->m_Count = 0;
    this->m_RenderCount = reg.GetNumberOfPixels( );

  } // fi

  // Get possible events
  const _TEvent* evt = dynamic_cast< const _TEvent* >( &e );
  _TFrontEvent fevt;
  _TMarkEvent mevt;
  _TCollisionEvent cevt;
  _TEndEvent eevt;

  if( evt != NULL )
  {
    if( fevt.CheckEvent( evt ) )
    {
      if( this->m_Marks->GetPixel( evt->Node.Vertex ) == -1 )
      {
        typename _TImage::PointType pnt;
        image->TransformIndexToPhysicalPoint( evt->Node.Vertex, pnt );

        long pId = this->m_Data->GetNumberOfPoints( );
        this->m_Data->GetVerts( )->InsertNextCell( 1 );
        this->m_Data->GetVerts( )->InsertCellPoint( pId );
        this->m_Data->GetPoints( )->
          InsertNextPoint( pnt[ 0 ], pnt[ 1 ], pnt[ 2 ] );
        this->m_Data->GetPointData( )->
          GetScalars( )->InsertNextTuple1( 0.5 );
        this->m_Data->Modified( );

        this->m_Marks->SetPixel( evt->Node.Vertex, pId );
        this->m_Count++;

        // Render visual debug
        double per = double( this->m_RenderCount ) * this->m_RenderPercentage;
        if( double( this->m_Count ) >= per )
          this->m_RenderWindow->Render( );
        if( double( this->m_Count ) >= per )
          this->m_Count = 0;

      } // fi
      return;
    }
    else if( mevt.CheckEvent( evt ) )
    {
      // TODO: std::cout << "mark" << std::endl;
      return;

    } // fi

    if( cevt.CheckEvent( evt ) )
    {
      // TODO: std::cout << "collision" << std::endl;
      return;

    } // fi

    if( eevt.CheckEvent( evt ) )
    {
      this->m_RenderWindow->Render( );
      ren->RemoveActor( this->m_Actor );
      this->m_RenderWindow->Render( );
      this->m_Marks = NULL;
      this->m_Data = NULL;
      this->m_Mapper = NULL;
      this->m_Actor = NULL;
      return;

    } // fi
  }
  else
  {
    const _TBacktrackingEvent* bevt =
      dynamic_cast< const _TBacktrackingEvent* >( &e );
    const _TEndBacktrackingEvent* ebevt =
      dynamic_cast< const _TEndBacktrackingEvent* >( &e );
    if( bevt != NULL )
    {
      static const unsigned long nColors = 10;
      double back_id = double( bevt->BackId % nColors ) / double( nColors );
      typename _TImage::PointType pnt;
      image->TransformIndexToPhysicalPoint( bevt->Node, pnt );

      long pId = this->m_Data->GetNumberOfPoints( );
      this->m_Data->GetVerts( )->InsertNextCell( 1 );
      this->m_Data->GetVerts( )->InsertCellPoint( pId );
      this->m_Data->GetPoints( )->
        InsertNextPoint( pnt[ 0 ], pnt[ 1 ], pnt[ 2 ] );
      this->m_Data->GetPointData( )->
        GetScalars( )->InsertNextTuple1( back_id );
      this->m_Data->Modified( );
      return;

    } // fi

    if( ebevt != NULL )
    {
      this->m_RenderWindow->Render( );
      return;

    } // fi

  } // fi
}

// -------------------------------------------------------------------------
template< class F, class R >
fpa::VTK::Image3DObserver< F, R >::
Image3DObserver( )
  : Superclass( ),
    m_RenderWindow( NULL ),
    m_RenderPercentage( double( 0.0001 ) )
{
}

#endif // __FPA__VTK__IMAGE3DOBSERVER__HXX__

// eof - $RCSfile$