// file: examples/Triangulation_3/example_tds.C

#include <CGAL/Triangulation_data_structure_3.h>
#include <iostream>
#include <fstream>
#include <cassert>
#include <vector>

typedef CGAL::Triangulation_data_structure_3<>      Tds;

typedef Tds::size_type                              size_type;
typedef Tds::Cell_handle                            Cell_handle;
typedef Tds::Vertex_handle                          Vertex_handle;

int main()
{
  Tds T;

  assert( T.number_of_vertices() == 0 );
  assert( T.dimension() == -2 );
  assert( T.is_valid() );

  std::vector<Vertex_handle> PV(7);

  PV[0] = T.insert_increase_dimension();
  assert( T.number_of_vertices() == 1 );
  assert( T.dimension() == -1 );
  assert( T.is_valid() );

  // each of the following insertions of vertices increases the dimension
  for ( int i=1; i<5; i++ ) {
    PV[i] = T.insert_increase_dimension(PV[0]);
    assert( T.number_of_vertices() == (size_type) i+1 );
    assert( T.dimension() == i-1 );
    assert( T.is_valid() );
  }
  assert( T.number_of_cells() == 5 );

  // we now have a simplex in dimension 4

  // cell incident to PV[0]
  Cell_handle c = PV[0]->cell();
  int ind;
  bool check = c->has_vertex( PV[0], ind );
  assert( check );
  // PV[0] is the vertex of index ind in c

  // insertion of a new vertex in the facet opposite to PV[0]
  PV[5] = T.insert_in_facet(c, ind);
  
  assert( T.number_of_vertices() == 6 );
  assert( T.dimension() == 3 );
  assert( T.is_valid() );

  // insertion of a new vertex in c
  PV[6] = T.insert_in_cell(c);

  assert( T.number_of_vertices() == 7 );
  assert( T.dimension() == 3 );
  assert( T.is_valid() );

  std::ofstream oFileT("output_tds",std::ios::out);
  // writing file output_tds; 
  oFileT << T; 

  return 0;
}
