#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkPolyData.h>
#include <vtkIdList.h>
#include <vtkCell.h>
#include <vtkTriangleFilter.h>
#include <vtkDataSetMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkIdTypeArray.h>
#include <vtkSelectionNode.h>
#include <vtkSelection.h>
#include <vtkExtractSelection.h>
#include <vtkProperty.h>

#include <list>

int main(int, char *[])
{
  //Create a sphere
  vtkSmartPointer<vtkSphereSource> sphereSource =
      vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->Update();

  vtkSmartPointer<vtkTriangleFilter> triangleFilter =
    vtkSmartPointer<vtkTriangleFilter>::New();
  triangleFilter->SetInputConnection(sphereSource->GetOutputPort());
  triangleFilter->Update();

  // Find all cells connected to point 0
  vtkIdType cellId = 0;

  vtkSmartPointer<vtkIdList> cellPointIds =
    vtkSmartPointer<vtkIdList>::New();
  triangleFilter->GetOutput()->GetCellPoints(cellId, cellPointIds);

  // neighbor cells may be listed multiple times
  // use std::set instead of std::list if you want a unique list of neighbors
  std::list<vtkIdType> neighbors;

  /*For each vertice of the cell, we calculate which cells uses that point.
   So if we make this, for each vertice, we have all the neighbors.
   In the case we use ''cellPointIds'' as a parameter of ''GeteCellNeighbors'',
   we will obtain an empty set. Because the only cell that is using that set of points
   is the current one. That is why we have to make each vertice at time.*/

  for(vtkIdType i = 0; i < cellPointIds->GetNumberOfIds(); i++)
  {
    vtkSmartPointer<vtkIdList> idList =
      vtkSmartPointer<vtkIdList>::New();
    idList->InsertNextId(cellPointIds->GetId(i));

    //get the neighbors of the cell
    vtkSmartPointer<vtkIdList> neighborCellIds =
      vtkSmartPointer<vtkIdList>::New();

    triangleFilter->GetOutput()->GetCellNeighbors(cellId, idList, neighborCellIds);

    for(vtkIdType j = 0; j < neighborCellIds->GetNumberOfIds(); j++)
    {
      neighbors.push_back(neighborCellIds->GetId(j));
    }

  }

  std::cout << "Point neighbor ids are: " << std::endl;

  for(std::list<vtkIdType>::iterator it1 = neighbors.begin(); it1 != neighbors.end(); it1++)
  {
    std::cout << " " << *it1;
  }
  std::cout << std::endl;


  vtkSmartPointer<vtkDataSetMapper> sphereMapper =
    vtkSmartPointer<vtkDataSetMapper>::New();
  sphereMapper->SetInputConnection(sphereSource->GetOutputPort());
  vtkSmartPointer<vtkActor> sphereActor =
    vtkSmartPointer<vtkActor>::New();
  sphereActor->SetMapper(sphereMapper);
  sphereActor->GetProperty()->SetEdgeColor(0, 0, 0);
  sphereActor->GetProperty()->EdgeVisibilityOn();

  vtkSmartPointer<vtkDataSetMapper> mainCellMapper =
    vtkSmartPointer<vtkDataSetMapper>::New();

  vtkSmartPointer<vtkDataSetMapper> neighborCellsMapper =
    vtkSmartPointer<vtkDataSetMapper>::New();

  // Create a dataset with the cell of interest
  {
    vtkSmartPointer<vtkIdTypeArray> ids =
        vtkSmartPointer<vtkIdTypeArray>::New();
    ids->SetNumberOfComponents(1);
    ids->InsertNextValue(cellId);

    vtkSmartPointer<vtkSelectionNode> selectionNode =
      vtkSmartPointer<vtkSelectionNode>::New();
    selectionNode->SetFieldType(vtkSelectionNode::CELL);
    selectionNode->SetContentType(vtkSelectionNode::INDICES);
    selectionNode->SetSelectionList(ids);

    vtkSmartPointer<vtkSelection> selection =
        vtkSmartPointer<vtkSelection>::New();
    selection->AddNode(selectionNode);

    vtkSmartPointer<vtkExtractSelection> extractSelection =
        vtkSmartPointer<vtkExtractSelection>::New();
    extractSelection->SetInputConnection(0, sphereSource->GetOutputPort());
#if VTK_MAJOR_VERSION <= 5
    extractSelection->SetInput(1, selection);
#else
    extractSelection->SetInputData(1, selection);
#endif
    extractSelection->Update();

    mainCellMapper->SetInputConnection(extractSelection->GetOutputPort());

  }

  vtkSmartPointer<vtkActor> mainCellActor =
    vtkSmartPointer<vtkActor>::New();
  mainCellActor->SetMapper(mainCellMapper);
  mainCellActor->GetProperty()->SetColor(1,0,0);

  // Create a dataset with the neighbor cells
  {
    vtkSmartPointer<vtkIdTypeArray> ids =
        vtkSmartPointer<vtkIdTypeArray>::New();
    ids->SetNumberOfComponents(1);
    for(std::list<vtkIdType>::iterator it1 = neighbors.begin(); it1 != neighbors.end(); it1++)
    {
      ids->InsertNextValue(*it1);
    }

    vtkSmartPointer<vtkSelectionNode> selectionNode =
      vtkSmartPointer<vtkSelectionNode>::New();
    selectionNode->SetFieldType(vtkSelectionNode::CELL);
    selectionNode->SetContentType(vtkSelectionNode::INDICES);
    selectionNode->SetSelectionList(ids);

    vtkSmartPointer<vtkSelection> selection =
        vtkSmartPointer<vtkSelection>::New();
    selection->AddNode(selectionNode);

    vtkSmartPointer<vtkExtractSelection> extractSelection =
        vtkSmartPointer<vtkExtractSelection>::New();
    extractSelection->SetInputConnection(0, sphereSource->GetOutputPort());
#if VTK_MAJOR_VERSION <= 5
    extractSelection->SetInput(1, selection);
#else
    extractSelection->SetInputData(1, selection);
#endif
    extractSelection->Update();

    neighborCellsMapper->SetInputConnection(extractSelection->GetOutputPort());

  }

  vtkSmartPointer<vtkActor> neighborCellsActor =
    vtkSmartPointer<vtkActor>::New();
  neighborCellsActor->SetMapper(neighborCellsMapper);
  neighborCellsActor->GetProperty()->SetColor(0,1,0);

  //Create a renderer, render window, and interactor
  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  //Add the actors to the scene
  renderer->AddActor(sphereActor);
  renderer->AddActor(mainCellActor);
  renderer->AddActor(neighborCellsActor);
  renderer->SetBackground(.3, .2, .1); // Background color dark red

  //Render and interact
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}
