// Copyright (c) 2003-2007  INRIA Sophia-Antipolis (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v5.6/Surface_mesher/include/CGAL/IO/Complex_2_in_triangulation_3_to_medit.h $
// $Id: Complex_2_in_triangulation_3_to_medit.h 2402f3f 2020-09-10T16:14:58+01:00 Andreas Fabri
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s)     : Steve Oudot, Laurent Rineau, Nader Salman

#ifndef CGAL_COMPLEX_2_IN_TRIANGULATION_3_TO_MEDIT_H
#define CGAL_COMPLEX_2_IN_TRIANGULATION_3_TO_MEDIT_H

#include <CGAL/license/Surface_mesher.h>

#include <CGAL/disable_warnings.h>

#include <iomanip>
#include <stack>
#include <unordered_map>

namespace CGAL {

template <class C2t3>
void
output_surface_facets_to_medit (std::ostream& os, const C2t3& c2t3)
{
  typedef typename C2t3::Triangulation Tr;
  typedef typename Tr::Finite_facets_iterator Finite_facets_iterator;
  typedef typename Tr::Finite_vertices_iterator Finite_vertices_iterator;
  typedef typename Tr::Vertex_handle Vertex_handle;
  typedef typename Tr::Point Point;

  // Header.
  const Tr& tr = c2t3.triangulation();

  os << "MeshVersionFormatted 1 \n"
     << "Dimension \n"
     << "3\n\n";

  //os << std::setprecision(20);

  std::unordered_map<Vertex_handle, int> V;

  for(typename C2t3::Facet_iterator
        fit = c2t3.facets_begin(),
        end = c2t3.facets_end();
      fit != end; ++fit)
  {
    V[fit->first->vertex(tr.vertex_triple_index(fit->second, 0))] = 0;
    V[fit->first->vertex(tr.vertex_triple_index(fit->second, 1))] = 0;
    V[fit->first->vertex(tr.vertex_triple_index(fit->second, 2))] = 0;
  }

  // Finite vertices coordinates.
  os << "Vertices\n"
     << V.size() << " \n";


  int inum = 0;
  for(Finite_vertices_iterator vit = tr.finite_vertices_begin();
      vit != tr.finite_vertices_end();
      ++vit)
  {
    auto it = V.find(vit);
    if(it != V.end()){
      it->second = inum++;
      Point p = static_cast<Point>(vit->point());
      os << p.x() << " " << p.y() << " " << p.z() << " 0 \n";
    }
  }


  // Finite facets indices.
  os << "\nTriangles\n"
     << c2t3.number_of_facets() << " \n";

  for( Finite_facets_iterator fit = tr.finite_facets_begin();
                              fit != tr.finite_facets_end(); ++fit)
  {
    if ((*fit).first->is_facet_on_surface((*fit).second)==true)
    {
      for (int i=0; i<4; i++)
        if (i != (*fit).second)
          os << V[(*fit).first->vertex(i)]+1 << " ";

      os << "0 \n"; // without color.
    }
  }
  // Footer
  os << "\nEnd\n";
}

} // end of namespace CGAL

#include <CGAL/enable_warnings.h>

#endif  // CGAL_COMPLEX_2_IN_TRIANGULATION_3_TO_MEDIT_H

