// Copyright (c) 1999-2006  INRIA Sophia-Antipolis (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v5.4/Triangulation_3/include/CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h $
// $Id: Delaunay_triangulation_cell_base_with_circumcenter_3.h d1a323c 2020-03-26T19:24:14+01:00 Sébastien Loriot
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s)     : Monique Teillaud <Monique.Teillaud@sophia.inria.fr>
//                 Sylvain Pion

// cell of a triangulation of any dimension <=3,
// storing its circumcenter lazily.

#ifndef CGAL_DELAUNAY_TRIANGULATION_CELL_BASE_WITH_CIRCUMCENTER_3_H
#define CGAL_DELAUNAY_TRIANGULATION_CELL_BASE_WITH_CIRCUMCENTER_3_H

#include <CGAL/license/Triangulation_3.h>



#include <CGAL/basic.h>
#include <CGAL/triangulation_assertions.h>
#include <CGAL/Delaunay_triangulation_cell_base_3.h>

namespace CGAL {

template < typename GT, typename Cb = Delaunay_triangulation_cell_base_3<GT> >
class Delaunay_triangulation_cell_base_with_circumcenter_3
  : public Cb
{
  typedef typename GT::Point_3                         Point;

  mutable Point * circumcenter_;

public:
  void invalidate_circumcenter()
  {
      if (circumcenter_) {
          delete circumcenter_;
          circumcenter_ = nullptr;
      }
  }

public:
  typedef typename Cb::Vertex_handle                   Vertex_handle;
  typedef typename Cb::Cell_handle                     Cell_handle;

  typedef GT                                           Geom_traits;

  template < typename TDS2 >
  struct Rebind_TDS {
    typedef typename Cb::template Rebind_TDS<TDS2>::Other         Cb2;
    typedef Delaunay_triangulation_cell_base_with_circumcenter_3<GT, Cb2>  Other;
  };

  Delaunay_triangulation_cell_base_with_circumcenter_3()
    : Cb(), circumcenter_(nullptr) {}

  Delaunay_triangulation_cell_base_with_circumcenter_3
        (const Delaunay_triangulation_cell_base_with_circumcenter_3 &c)
    : Cb(c), circumcenter_(c.circumcenter_ != nullptr ? new Point(*(c.circumcenter_)) : nullptr)
  {}

  Delaunay_triangulation_cell_base_with_circumcenter_3
        (Delaunay_triangulation_cell_base_with_circumcenter_3 &&c)
    : Cb(std::move(c)), circumcenter_(std::exchange(c.circumcenter_, nullptr))
  {
  }

  Delaunay_triangulation_cell_base_with_circumcenter_3&
  operator=(const Delaunay_triangulation_cell_base_with_circumcenter_3 &c)
  {
      Delaunay_triangulation_cell_base_with_circumcenter_3 tmp=c;
      std::swap(tmp, *this);
      return *this;
  }

  Delaunay_triangulation_cell_base_with_circumcenter_3&
  operator=(Delaunay_triangulation_cell_base_with_circumcenter_3 &&c)
  {
      Cb::operator=(std::move(c));
      circumcenter_ = std::exchange(c.circumcenter_, nullptr);
      return *this;
  }

  Delaunay_triangulation_cell_base_with_circumcenter_3(
                            Vertex_handle v0, Vertex_handle v1,
                            Vertex_handle v2, Vertex_handle v3)
    : Cb(v0, v1, v2, v3), circumcenter_(nullptr) {}

  Delaunay_triangulation_cell_base_with_circumcenter_3(
                            Vertex_handle v0, Vertex_handle v1,
                            Vertex_handle v2, Vertex_handle v3,
                            Cell_handle   n0, Cell_handle   n1,
                            Cell_handle   n2, Cell_handle   n3)
    : Cb(v0, v1, v2, v3, n0, n1, n2, n3), circumcenter_(nullptr) {}

  ~Delaunay_triangulation_cell_base_with_circumcenter_3()
  {
      delete circumcenter_;
  }

  // We must override the functions that modify the vertices.
  // And if the point inside a vertex is modified, we fail,
  // but there's not much we can do for this now.
  void set_vertex(int i, Vertex_handle v)
  {
      invalidate_circumcenter();
      Cb::set_vertex(i, v);
  }

  void set_vertices()
  {
      invalidate_circumcenter();
      Cb::set_vertices();
  }

  void set_vertices(Vertex_handle v0, Vertex_handle v1,
                    Vertex_handle v2, Vertex_handle v3)
  {
      invalidate_circumcenter();
      Cb::set_vertices(v0, v1, v2, v3);
  }

  const Point& circumcenter(const Geom_traits& gt = Geom_traits()) const
  {
      if (circumcenter_ == nullptr) {
        circumcenter_ = new Point(this->Cb::circumcenter(gt));
      } else {
        CGAL_expensive_assertion(
          this->Cb::circumcenter(gt) == *circumcenter);
      }

      return *circumcenter_;
  }
};

} //namespace CGAL

#endif // CGAL_DELAUNAY_TRIANGULATION_CELL_BASE_WITH_CIRCUMCENTER_3_H
