// Copyright (c) 1997-2002  Max-Planck-Institute Saarbruecken (Germany).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1.1/Nef_3/include/CGAL/Nef_3/SHalfedge.h $
// $Id: include/CGAL/Nef_3/SHalfedge.h 08b27d3db14 $
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s)     : Michael Seel        <seel@mpi-sb.mpg.de>
//                 Miguel Granados     <granados@mpi-sb.mpg.de>
//                 Susan Hert          <hert@mpi-sb.mpg.de>
//                 Lutz Kettner        <kettner@mpi-sb.mpg.de>
//                 Peter Hachenberger  <hachenberger@mpi-sb.mpg.de>
#ifndef CGAL_NEF_SHALFEDGE_H
#define CGAL_NEF_SHALFEDGE_H

#include <CGAL/license/Nef_3.h>


#include <string>
#include <sstream>
#include <CGAL/IO/io.h>
#include <CGAL/IO/Verbose_ostream.h>
#include <CGAL/Nef_3/SNC_iteration.h>

#undef CGAL_NEF_DEBUG
#define CGAL_NEF_DEBUG 83
#include <CGAL/Nef_2/debug.h>

#ifndef CGAL_I_DO_WANT_TO_USE_GENINFO
#include <any>
#endif

namespace CGAL {

template <typename Refs>
class SHalfedge_base  {
  #ifdef CGAL_I_DO_WANT_TO_USE_GENINFO
  typedef void* GenPtr;
  #else
  typedef std::any GenPtr;
  #endif
  typedef typename Refs::Mark  Mark;
  typedef typename Refs::Sphere_circle  Sphere_circle;

  typedef typename Refs::Halfedge_handle Halfedge_handle;
  typedef typename Refs::Halfedge_const_handle Halfedge_const_handle;
  typedef typename Refs::SVertex_handle SVertex_handle;
  typedef typename Refs::SVertex_const_handle SVertex_const_handle;
  typedef typename Refs::SHalfedge_handle SHalfedge_handle;
  typedef typename Refs::SHalfedge_const_handle SHalfedge_const_handle;
  typedef typename Refs::SFace_handle SFace_handle;
  typedef typename Refs::SFace_const_handle SFace_const_handle;
  typedef typename Refs::Halffacet_handle Halffacet_handle;
  typedef typename Refs::Halffacet_const_handle Halffacet_const_handle;
  typedef typename Refs::SHalfedge_around_facet_circulator
    SHalfedge_around_facet_circulator;
  typedef typename Refs::SHalfedge_around_sface_circulator
    SHalfedge_around_sface_circulator;

  // Role within local graph:
  SVertex_handle     source_;
  SHalfedge_handle   sprev_, snext_;
  SFace_handle       incident_sface_;
  SHalfedge_handle   twin_;
  // Topology within global Nef structure:
  SHalfedge_handle   prev_, next_;
  Halffacet_handle   facet_;
  GenPtr             info_;
  // temporary needed:
  Mark               mark_;
  Sphere_circle      circle_;

 public:

  SHalfedge_base() : source_(), sprev_(), snext_(),
    incident_sface_(), twin_(),
    prev_(), next_(), facet_(),
    info_(), mark_(), circle_() {}

    ~SHalfedge_base() {
      CGAL_NEF_TRACEN("  destroying SHalfedge_base item "<<&*this);
    }

    SHalfedge_base(const SHalfedge_base<Refs>& e)
      {
        source_ = e.source_;
        sprev_ = e.sprev_;
        snext_ = e.snext_;
        incident_sface_ = e.incident_sface_;
        twin_ = e.twin_;
        prev_ = e.prev_;
        next_ = e.next_;
        facet_ = e.facet_;
        info_ = 0;
        mark_ = e.mark_;
        circle_ = e.circle_;
      }

    SHalfedge_base<Refs>& operator=(const SHalfedge_base<Refs>& e)
      {
        source_ = e.source_;
        sprev_ = e.sprev_;
        snext_ = e.snext_;
        incident_sface_ = e.incident_sface_;
        twin_ = e.twin_;
        prev_ = e.prev_;
        next_ = e.next_;
        facet_ = e.facet_;
        info_ = 0;
        mark_ = e.mark_;
        circle_ = e.circle_;
        return *this;
      }

    SHalfedge_base<Refs>& operator=(SHalfedge_base<Refs>&& e) noexcept
      {
        source_ = std::move(e.source_);
        sprev_ = std::move(e.sprev_);
        snext_ = std::move(e.snext_);
        incident_sface_ = std::move(e.incident_sface_);
        twin_ = std::move(e.twin_);
        prev_ = std::move(e.prev_);
        next_ = std::move(e.next_);
        facet_ = std::move(e.facet_);
        info_ = 0;
        mark_ = std::move(e.mark_);
        circle_ = std::move(e.circle_);
        return *this;
      }

    Mark& mark() { return mark_; }
    const Mark& mark() const { return mark_; }

    SHalfedge_handle& twin() { return twin_; }
    SHalfedge_const_handle twin() const { return twin_; }

    SVertex_handle& source() { return source_; }
    SVertex_const_handle source() const { return source_; }

    SVertex_handle& target() { return twin()->source(); }
    SVertex_const_handle target() const { return twin()->source(); }

    SHalfedge_handle& prev() { return prev_; }
    SHalfedge_const_handle prev() const { return prev_; }

    SHalfedge_handle& next() { return next_; }
    SHalfedge_const_handle next() const { return next_; }

    SHalfedge_handle& sprev() { return sprev_; }
    SHalfedge_const_handle sprev() const { return sprev_; }

    SHalfedge_handle& snext() { return snext_; }
    SHalfedge_const_handle snext() const { return snext_; }

    SHalfedge_handle& cyclic_adj_succ()
      { return sprev()->twin(); }
    SHalfedge_const_handle cyclic_adj_succ() const
    { return sprev()->twin(); }

    SHalfedge_handle& cyclic_adj_pred(SHalfedge_const_handle e)
      { return e->twin()->snext(); }
    SHalfedge_const_handle cyclic_adj_pred(SHalfedge_const_handle e) const
    { return e->twin()->snext(); }

    Sphere_circle& circle() { return circle_; }
    const Sphere_circle& circle() const { return circle_; }

    SFace_handle& incident_sface() { return incident_sface_; }
    SFace_const_handle incident_sface() const { return incident_sface_; }

    Halffacet_handle& facet() { return facet_; }
    Halffacet_const_handle facet() const { return facet_; }

    GenPtr& info() { return info_; }
    const GenPtr& info() const { return info_; }

    bool in_outer_facet_cycle() const {
      if(++facet()->facet_cycles_begin() ==
         facet()->facet_cycles_end()) return true;
      const Refs* sncp = source()->source()->sncp();
      SHalfedge_around_facet_circulator sfc(this), send(sfc);
      do {
        if(sncp()->is_boundary_item(sfc))
          break;
      } while(++sfc != send);
      CGAL_assertion(sncp()->is_boundary_item(sfc));
      if(sfc == facet()->facet_cycles_begin())
        return true;
      return false;
    }

    bool in_inner_facet_cycle() const {
      return !in_outer_facet_cycle();
    }

    bool in_outer_sface_cycle() const {
      if(++incident_sface()->sface_cycles_begin() ==
         incident_sface()->sface_cycles_end()) return true;
      const Refs* sncp = source()->source()->sncp();
      SHalfedge_around_sface_circulator sfc(this), send(sfc);
      do {
        if(sncp()->is_sm_boundary_item(sfc))
          break;
      } while(++sfc != send);
      CGAL_assertion(sncp()->is_sm_boundary_item(sfc));
      if(sfc == incident_sface()->sface_cycles_begin())
        return true;
      return false;
    }

   bool in_inner_sface_cycle() const {
      return !in_outer_sface_cycle();
    }

    std::string debug() const
      { std::stringstream os;
        CGAL::IO::set_pretty_mode(os);
        os <<"e[ "<<source_->debug()<<", "
           <<twin_->source_->debug()
    #ifdef CGAL_I_DO_WANT_TO_USE_GENINFO
     <<" "<<info_
    #endif
     <<" ] ";
        return os.str();
      }

    bool is_twin() const { return (&*twin_ < this); }

    bool is_valid( bool verb = false, int level = 0) const {

      Verbose_ostream verr(verb);
      verr << "begin CGAL::SNC_items<...>::SHalfedge_base::is_valid( verb=true, "
        "level = " << level << "):" << std::endl;

      bool valid = (source_ != SVertex_handle() &&
                    source_ != nullptr &&
                    source_ != Halfedge_handle());
      valid = valid && (twin_  != SHalfedge_handle() && twin_  != nullptr);
      valid = valid && (sprev_ != SHalfedge_handle() && sprev_ != nullptr);
      valid = valid && (snext_ != SHalfedge_handle() && snext_ != nullptr);
      valid = valid && (prev_  != SHalfedge_handle() && prev_  != nullptr);
      valid = valid && (next_  != SHalfedge_handle() && next_  != nullptr);

      valid = valid && (incident_sface_ != SFace_handle() &&
                        incident_sface_ != nullptr);
      valid = valid && (facet_ != Halffacet_handle() &&
                        facet_ != nullptr);
      valid = valid && (circle_.d() == 0);
      valid = valid && (circle_.a() != 0 || circle_.b() != 0 || circle_.c() !=0);

      verr << "end of CGAL::SNC_items<...>::SHalfedge_base::is_valid(): structure is "
           << ( valid ? "valid." : "NOT VALID.") << std::endl;

      return valid;
    }

}; // SHalfedge_base

} //namespace CGAL
#endif //CGAL_NEF_SHALFEDGE_H
