#include <vtkSmartPointer.h>
#include <vtkTetra.h>
#include <vtkCellArray.h>
#include <vtkXMLUnstructuredGridReader.h>
#include <vtkDataSetMapper.h>
#include <vtkActor.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkXMLUnstructuredGridWriter.h>
#include <vtkUnstructuredGrid.h>
#include <vtkPointData.h>
#include <vtkVertexGlyphFilter.h>

int main(int argc, char *argv[])
{
  // Parse command line arguments
  if(argc != 2)
  {
    std::cout << "Required arguments: OutputFilename" << std::endl;
    return EXIT_FAILURE;
  }

  std::string filename = argv[1];

  vtkSmartPointer<vtkPoints> points =
    vtkSmartPointer<vtkPoints>::New();
  points->InsertNextPoint(0, 0, 0);
  points->InsertNextPoint(1, 0, 0);
  points->InsertNextPoint(1, 1, 0);
  points->InsertNextPoint(0, 1, 1);

   vtkSmartPointer<vtkTetra> tetra =
    vtkSmartPointer<vtkTetra>::New();

  tetra->GetPointIds()->SetId(0, 0);
  tetra->GetPointIds()->SetId(1, 1);
  tetra->GetPointIds()->SetId(2, 2);
  tetra->GetPointIds()->SetId(3, 3);

  vtkSmartPointer<vtkCellArray> cellArray =
    vtkSmartPointer<vtkCellArray>::New();
  cellArray->InsertNextCell(tetra);


  vtkSmartPointer<vtkUnstructuredGrid> unstructuredGrid =
    vtkSmartPointer<vtkUnstructuredGrid>::New();
  unstructuredGrid->SetPoints(points);
  unstructuredGrid->SetCells(VTK_TETRA, cellArray);

  // Write file
  vtkSmartPointer<vtkXMLUnstructuredGridWriter> writer =
    vtkSmartPointer<vtkXMLUnstructuredGridWriter>::New();
  writer->SetFileName(filename.c_str());
  writer->SetInputData(unstructuredGrid);
  writer->Write();

  // Read and display file for verification that it was written correclty
  vtkSmartPointer<vtkXMLUnstructuredGridReader> reader =
    vtkSmartPointer<vtkXMLUnstructuredGridReader>::New();
  reader->SetFileName(filename.c_str());
  reader->Update();

  vtkSmartPointer<vtkDataSetMapper> mapper =
    vtkSmartPointer<vtkDataSetMapper>::New();
  mapper->SetInputConnection(reader->GetOutputPort());

  vtkSmartPointer<vtkActor> actor =
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);

  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer(renderer);
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow(renderWindow);

  renderer->AddActor(actor);
  renderer->SetBackground(.3, .6, .3); // Background color green

  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}
