// Copyright (c) 2019 GeometryFactory(France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1/Intersections_3/include/CGAL/Intersections_3/internal/Segment_3_Tetrahedron_3_intersection.h $
// $Id: include/CGAL/Intersections_3/internal/Segment_3_Tetrahedron_3_intersection.h b26b07a1242 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s)     : Maxime Gimeno
//

#ifndef CGAL_INTERNAL_INTERSECTIONS_3_TETRAHEDRON_3_SEGMENT_3_INTERSECTION_H
#define CGAL_INTERNAL_INTERSECTIONS_3_TETRAHEDRON_3_SEGMENT_3_INTERSECTION_H

#include <CGAL/Intersection_traits_3.h>
#include <CGAL/Intersections_3/internal/tetrahedron_lines_intersections_3.h>

#include <CGAL/kernel_basic.h>

namespace CGAL {
namespace Intersections {
namespace internal {

template<class K>
struct Tetrahedron_segment_intersection_3
  : public Tetrahedron_lines_intersection_3_base<K, typename K::Segment_3, Tetrahedron_segment_intersection_3<K> >
{
  typedef typename K::Segment_3 O;
  typedef Tetrahedron_lines_intersection_3_base<K,typename K::Segment_3, Tetrahedron_segment_intersection_3<K> > Base;
  typedef typename Base::Result_type result_type;

  Tetrahedron_segment_intersection_3(const typename K::Tetrahedron_3& tet,
                                     const O& o)
    : Base(tet, o)
  { }

  bool all_inside_test()
  {
    //if both segment extremities are inside tet, return the input segment.
    if(this->tet.has_on_bounded_side(this->o.source()) &&
       this->tet.has_on_bounded_side(this->o.target()))
    {
      typename K::Segment_3 result = this->o;
      this->output = result_type(std::forward<typename K::Segment_3>(result));
      return true;
    }
    return false;
  }

  bool are_extremities_inside_test()
  {
    //If one extremity is inside tet : return a segment
    if(this->tet.has_on_bounded_side(this->o.source()))
    {
      typename K::Segment_3 result(this->o.source(), this->res_points.front());
      this->output = result_type(std::forward<typename K::Segment_3>(result));
      return true;
    }
    else if(this->tet.has_on_bounded_side(this->o.target()))
    {
      typename K::Segment_3 result(this->res_points.front(), this->o.target());
      this->output = result_type(std::forward<typename K::Segment_3>(result));
      return true;
    }
    return false;
  }
};

template <class K>
typename Intersection_traits<K, typename K::Tetrahedron_3, typename K::Segment_3>::result_type
intersection(const typename K::Tetrahedron_3& tet,
             const typename K::Segment_3& seg,
             const K&)
{
  Tetrahedron_segment_intersection_3<K> solver(tet, seg);
  solver.do_procede();
  return solver.output;
}

template <class K>
typename Intersection_traits<K, typename K::Tetrahedron_3, typename K::Segment_3>::result_type
intersection(const typename K::Segment_3& seg,
             const typename K::Tetrahedron_3& tet,
             const K& k)
{
  return intersection(tet, seg, k);
}

} // namespace internal
} // namespace Intersections
} // namespace CGAL

#endif // CGAL_INTERNAL_INTERSECTIONS_3_TETRAHEDRON_3_Segment_3_INTERSECTION_H

