/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkCellCentersPointPlacer.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "vtkCellCentersPointPlacer.h"

#include "vtkObjectFactory.h"
#include "vtkRenderer.h"
#include "vtkProp.h"
#include "vtkPropCollection.h"
#include "vtkCellPicker.h"
#include "vtkAssemblyPath.h"
#include "vtkAssemblyNode.h"
#include "vtkInteractorObserver.h"
#include "vtkDataSet.h"
#include "vtkCell.h"
#include "vtkPoints.h"

vtkStandardNewMacro(vtkCellCentersPointPlacer);

//----------------------------------------------------------------------
vtkCellCentersPointPlacer::vtkCellCentersPointPlacer()
{
  this->PickProps    = vtkPropCollection::New();
  this->CellPicker   = vtkCellPicker::New();
  this->CellPicker->PickFromListOn();

  this->Mode = vtkCellCentersPointPlacer::CellPointsMean;
}

//----------------------------------------------------------------------
vtkCellCentersPointPlacer::~vtkCellCentersPointPlacer()
{
  this->PickProps->Delete();
  this->CellPicker->Delete();
}

//----------------------------------------------------------------------
void vtkCellCentersPointPlacer::AddProp(vtkProp *prop)
{
  this->PickProps->AddItem(prop);
  this->CellPicker->AddPickList(prop);
}

//----------------------------------------------------------------------
void vtkCellCentersPointPlacer::RemoveViewProp(vtkProp *prop)
{
  this->PickProps->RemoveItem( prop );
  this->CellPicker->DeletePickList( prop );
}

//----------------------------------------------------------------------
void vtkCellCentersPointPlacer::RemoveAllProps()
{
  this->PickProps->RemoveAllItems();
  this->CellPicker->InitializePickList(); // clear the pick list.. remove
                                          // old props from it...
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::HasProp(vtkProp *prop)
{
  return this->PickProps->IsItemPresent(prop);
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::GetNumberOfProps()
{
  return this->PickProps->GetNumberOfItems();
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::ComputeWorldPosition( vtkRenderer *ren,
                                        double  displayPos[2],
                                        double *vtkNotUsed(refWorldPos),
                                        double  worldPos[3],
                                        double  worldOrient[9] )
{
  return this->ComputeWorldPosition(ren, displayPos, worldPos, worldOrient);
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::ComputeWorldPosition( vtkRenderer *ren,
                                      double displayPos[2],
                                      double worldPos[3],
                                      double vtkNotUsed(worldOrient)[9] )
{
  vtkDebugMacro( << "Request for computing world position at " <<
    "display position of " << displayPos[0] << "," << displayPos[1] );

  if ( this->CellPicker->Pick(displayPos[0],
                              displayPos[1], 0.0, ren) )
  {
    if (vtkAssemblyPath *path = this->CellPicker->GetPath())
    {

      // We are checking if the prop present in the path is present
      // in the list supplied to us.. If it is, that prop will be picked.
      // If not, no prop will be picked.

      bool found = false;
      vtkAssemblyNode *node = nullptr;
      vtkCollectionSimpleIterator sit;
      this->PickProps->InitTraversal(sit);

      while (vtkProp *p = this->PickProps->GetNextProp(sit))
      {
        vtkCollectionSimpleIterator psit;
        path->InitTraversal(psit);

        for ( int i = 0; i < path->GetNumberOfItems() && !found ; ++i )
        {
          node = path->GetNextNode(psit);
          found = ( node->GetViewProp() == p );
        }

        if (found)
        {
          vtkIdType pickedCellId = this->CellPicker->GetCellId();
          vtkCell * pickedCell = this->CellPicker->
                  GetDataSet()->GetCell(pickedCellId);

          if (this->Mode == vtkCellCentersPointPlacer::ParametricCenter)
          {
            double pcoords[3];
            pickedCell->GetParametricCenter(pcoords);
            double *weights = new double[pickedCell->GetNumberOfPoints()];

            int subId;
            pickedCell->EvaluateLocation( subId, pcoords, worldPos, weights );
            delete [] weights;
          }

          if (this->Mode == vtkCellCentersPointPlacer::CellPointsMean)
          {
            const vtkIdType nPoints = pickedCell->GetNumberOfPoints();
            vtkPoints *points = pickedCell->GetPoints();
            worldPos[0] = worldPos[1] = worldPos[2] = 0.0;
            double pp[3];
            for (vtkIdType i = 0; i < nPoints; i++)
            {
              points->GetPoint(i, pp);
              worldPos[0] += pp[0];
              worldPos[1] += pp[1];
              worldPos[2] += pp[2];
            }

            worldPos[0] /= (static_cast< double >(nPoints));
            worldPos[1] /= (static_cast< double >(nPoints));
            worldPos[2] /= (static_cast< double >(nPoints));
          }

          if (this->Mode == vtkCellCentersPointPlacer::None)
          {
            this->CellPicker->GetPickPosition(worldPos);
          }

          return 1;
        }
      }
    }
  }

  return 0;
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::ValidateWorldPosition( double worldPos[3],
                                           double *vtkNotUsed(worldOrient) )
{
  return this->ValidateWorldPosition( worldPos );
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::ValidateWorldPosition(
                     double vtkNotUsed(worldPos)[3] )
{
  return 1;
}

//----------------------------------------------------------------------
int vtkCellCentersPointPlacer::ValidateDisplayPosition( vtkRenderer *,
                                      double vtkNotUsed(displayPos)[2] )
{
  return 1;
}

//----------------------------------------------------------------------
void vtkCellCentersPointPlacer::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);

  os << indent << "CellPicker: " << this->CellPicker << endl;
  if (this->CellPicker)
  {
    this->CellPicker->PrintSelf(os, indent.GetNextIndent());
  }

  os << indent << "PickProps: " << this->PickProps << endl;
  if (this->PickProps)
  {
    this->PickProps->PrintSelf(os, indent.GetNextIndent());
  }

  os << indent << "Mode: " << this->Mode << endl;
}