// Copyright (c) 2007  GeometryFactory (France).  All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1/BGL/include/CGAL/boost/graph/graph_traits_OpenMesh.h $
// $Id: include/CGAL/boost/graph/graph_traits_OpenMesh.h b26b07a1242 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s)     : Andreas Fabri, Philipp Moeller

#include <CGAL/Named_function_parameters.h>

#include <boost/graph/graph_traits.hpp>
#include <boost/graph/properties.hpp>

#include <CGAL/boost/iterator/transform_iterator.hpp>

#include <CGAL/boost/graph/internal/OM_iterator_from_circulator.h>
#include <CGAL/boost/graph/iterator.h>
#include <CGAL/Iterator_range.h>
#include <CGAL/boost/graph/helpers.h>
#include <CGAL/assertions.h>
#include <CGAL/hash_openmesh.h>

#if defined(BOOST_MSVC)
#  pragma warning(push)
#  pragma warning(disable:4267)
#endif

#ifndef OPEN_MESH_CLASS
  #error OPEN_MESH_CLASS is not defined
#endif

// note only the classes in CGAL::internal below are protected by the macro,
// the rest of the file is the shared implementation of graph_traits for
// OpenMesh::PolyMesh_ArrayKernelT<K> and OpenMesh::TriMesh_ArrayKernelT<K>
#ifndef CGAL_BOOST_GRAPH_TRAITS_GRAPH_TRAITS_OPENMESH_H
#define CGAL_BOOST_GRAPH_TRAITS_GRAPH_TRAITS_OPENMESH_H
namespace CGAL { namespace internal {

template <typename Halfedge_handle, typename OMeshEdge>
struct Convert_omesh_edge
{
  typedef OMesh_edge<Halfedge_handle> result_type;
  result_type operator()(const OMeshEdge& h) const {
    return result_type(Halfedge_handle(h.idx() * 2));
  }
};

template <typename Halfedge_handle>
struct Construct_omesh_edge
{
  typedef OMesh_edge<Halfedge_handle> result_type;
  template <typename T>
  result_type operator()(const T& h) const { return result_type(h); }
};

template <typename Halfedge_handle>
struct Construct_omesh_edge_opposite
{
  typedef OMesh_edge<Halfedge_handle> result_type;
  template <typename T>
  result_type operator()(const T& h) const { return result_type(h).opposite_edge(); }
};


} // internal
} // CGAL
#endif //CGAL_BOOST_GRAPH_TRAITS_GRAPH_TRAITS_OPENMESH_H

namespace boost {

template <class K>
struct graph_traits< OPEN_MESH_CLASS >
{
private:
  typedef OPEN_MESH_CLASS SM;

  struct SM_graph_traversal_category : public virtual boost::bidirectional_graph_tag,
                                       public virtual boost::vertex_list_graph_tag,
                                       public virtual boost::edge_list_graph_tag,
                                       public virtual boost::adjacency_graph_tag
  {};

public:
  // Graph
  typedef typename SM::VertexHandle                                        vertex_descriptor;
  typedef typename SM::Point                                               vertex_property_type;
  typedef typename CGAL::internal::OMesh_edge<typename SM::HalfedgeHandle> edge_descriptor;
  typedef boost::undirected_tag                                            directed_category;
  typedef boost::disallow_parallel_edge_tag                                edge_parallel_category;
  typedef SM_graph_traversal_category                                      traversal_category;

  // HalfedgeGraph
  typedef typename SM::HalfedgeHandle              halfedge_descriptor;

   // FaceGraph
  typedef typename SM::FaceHandle   face_descriptor;

  // VertexListGraph
  typedef typename SM::VertexIter   vertex_iterator;
  typedef unsigned int              vertices_size_type;
  // EdgeListGraph
  typedef boost::transform_iterator<
    CGAL::internal::Convert_omesh_edge<typename SM::HalfedgeHandle, typename SM::EdgeHandle>,
    typename SM::EdgeIter,
    edge_descriptor>                edge_iterator;

  typedef unsigned int              edges_size_type;
  // HalfEdgeListGraph
  typedef typename SM::HalfedgeIter halfedge_iterator;
  typedef unsigned int              halfedges_size_type;
  // FaceListGraph
  typedef typename SM::FaceIter     face_iterator;
  typedef unsigned int              faces_size_type;

  // IncidenceGraph
  typedef unsigned int              degree_size_type;


  typedef CGAL::In_edge_iterator<SM> in_edge_iterator;

  typedef CGAL::Out_edge_iterator<SM> out_edge_iterator;

  typedef CGAL::Vertex_around_target_iterator<SM> adjacency_iterator;

  // nulls
  static vertex_descriptor   null_vertex() { return vertex_descriptor(); }
  static face_descriptor     null_face()   { return face_descriptor(); }
  static halfedge_descriptor null_halfedge()   { return halfedge_descriptor(); }
};

template<typename K>
struct graph_traits< const OPEN_MESH_CLASS >
  : public graph_traits< OPEN_MESH_CLASS >
{ };

} // namespace boost

namespace OpenMesh {

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertices_size_type
num_vertices(const OPEN_MESH_CLASS& sm)
{
  return sm.n_vertices();
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::edges_size_type
num_edges(const OPEN_MESH_CLASS& sm)
{
  return sm.n_edges();
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::degree_size_type
degree(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
       const OPEN_MESH_CLASS& sm)
{
  return sm.valence(v);
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::degree_size_type
degree(typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor f,
       const OPEN_MESH_CLASS& sm)
{
  return sm.valence(f);
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::degree_size_type
out_degree(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
           const OPEN_MESH_CLASS& sm)
{
  return sm.valence(v);
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::degree_size_type
in_degree(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
          const OPEN_MESH_CLASS& sm)
{
  return sm.valence(v);
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
source(typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor e,
       const OPEN_MESH_CLASS& sm)
{
  return sm.from_vertex_handle(e.halfedge());
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
source(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
       const OPEN_MESH_CLASS& sm)
{
  return sm.from_vertex_handle(h);
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
target(typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor e,
       const OPEN_MESH_CLASS& sm)
{
  return sm.to_vertex_handle(e.halfedge());
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
target(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
       const OPEN_MESH_CLASS& sm)
{
  return sm.to_vertex_handle(h);
}

template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_iterator>
vertices(const OPEN_MESH_CLASS& sm)
{
  return CGAL::make_range(sm.vertices_sbegin(), sm.vertices_end());
}


template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::edge_iterator>
edges(const OPEN_MESH_CLASS& sm)
{
  typedef typename boost::graph_traits<OPEN_MESH_CLASS >::edge_iterator iterator;
  iterator beg(sm.edges_sbegin());
  iterator end(sm.edges_end());
  return CGAL::make_range(beg,end);
}


template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::in_edge_iterator>
in_edges(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
         const OPEN_MESH_CLASS& sm)
{
  typedef typename boost::graph_traits<OPEN_MESH_CLASS >::in_edge_iterator Iter;

  return CGAL::make_range(Iter(halfedge(v,sm),sm), Iter(halfedge(v,sm),sm,1));
}


template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::out_edge_iterator>
out_edges(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
          const OPEN_MESH_CLASS& sm)
{
  typedef typename boost::graph_traits<OPEN_MESH_CLASS >::out_edge_iterator Iter;
  return CGAL::make_range(Iter(halfedge(v,sm),sm), Iter(halfedge(v,sm),sm,1));
}


template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::adjacency_iterator>
adjacent_vertices(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
                 const OPEN_MESH_CLASS& sm)
{
  return CGAL::vertices_around_target(v,sm);
}




template<typename K>
std::pair<typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor,
          bool>
edge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor u,
     typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
     const OPEN_MESH_CLASS& sm) {
  typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor
    he(sm.find_halfedge(u, v));
  return std::make_pair(he, he.is_valid());
}


//
// HalfedgeGraph
//
template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
next(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
     const OPEN_MESH_CLASS& sm)
{
  return sm.next_halfedge_handle(h);
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
prev(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
     const OPEN_MESH_CLASS& sm)
{
  return sm.prev_halfedge_handle(h);
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
opposite(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
         const OPEN_MESH_CLASS& sm)
{
  return sm.opposite_halfedge_handle(h);
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor
edge(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
     const OPEN_MESH_CLASS& /*sm*/)
{
  return typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor(h);
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor e,
         const OPEN_MESH_CLASS&)
{
  return e.halfedge();
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
         const OPEN_MESH_CLASS& sm)
{
  if(sm.halfedge_handle(v) == boost::graph_traits<OPEN_MESH_CLASS >::null_halfedge()){
    return boost::graph_traits<OPEN_MESH_CLASS >::null_halfedge();
  }
  // prev because OpenMesh stores out-going halfedges
  // return sm.prev_halfedge_handle(sm.halfedge_handle(v));
  return sm.opposite_halfedge_handle(sm.halfedge_handle(v));
}


template <typename K>
std::pair<
  typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor,
  bool
>
halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor u,
         typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
         const OPEN_MESH_CLASS& sm)
{
  typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h = sm.find_halfedge(u, v);
  return std::make_pair(h, h.is_valid());
}



//
// HalfedgeListGraph
//
template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_iterator>
halfedges(const OPEN_MESH_CLASS& sm)
{
  return CGAL::make_range(sm.halfedges_sbegin(), sm.halfedges_end());
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedges_size_type
num_halfedges(const OPEN_MESH_CLASS& sm)
{
  return sm.n_halfedges();
}



//
// MutableHalfedgeGraph
//
template<typename K>
void
set_next(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h1,
         typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h2,
         OPEN_MESH_CLASS& sm)
{
  sm.set_next_halfedge_handle(h1, h2);
}



template<typename K>
void
set_target(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
           typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
           OPEN_MESH_CLASS& sm)
{
  sm.set_vertex_handle(h, v);
}


template<typename K>
void
set_halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
             typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
             OPEN_MESH_CLASS& sm)
{
  sm.set_halfedge_handle(v, sm.opposite_halfedge_handle(h));
}


template<typename K>
void
adjust_border_halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
                       OPEN_MESH_CLASS& sm)
{
  sm.adjust_outgoing_halfedge(v);
}

template<typename K>
void
garbage_collection(OPEN_MESH_CLASS& sm)
{
  sm.garbage_collection();
}

template<typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor
add_edge(OPEN_MESH_CLASS& sm)
{
  return edge(sm.new_edge(boost::graph_traits<OPEN_MESH_CLASS >::null_vertex(),
                          boost::graph_traits<OPEN_MESH_CLASS >::null_vertex() ), sm);
}


//
// FaceGraph
//
template<typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor
halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor f,
     const OPEN_MESH_CLASS& sm)
{
  return sm.halfedge_handle(f);
}

template<typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor
face(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
     const OPEN_MESH_CLASS& sm)
{
  return sm.face_handle(h);
}



//
// MutableFaceGraph
//
template<typename K>
void
set_face(typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
         typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor f,
         OPEN_MESH_CLASS& sm)
{
  sm.set_face_handle(h, f);
}


template<typename K>
void
set_halfedge(typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor f,
             typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor h,
             OPEN_MESH_CLASS& sm)
{
  sm.set_halfedge_handle(f, h);
}

template<typename K>
void
reserve(OPEN_MESH_CLASS& tm,
        typename boost::graph_traits< OPEN_MESH_CLASS >::vertices_size_type nv,
        typename boost::graph_traits< OPEN_MESH_CLASS >::edges_size_type ne,
        typename boost::graph_traits< OPEN_MESH_CLASS >::faces_size_type nf)
{
  tm.reserve(nv, ne, nf);
}

//
// FaceListGraph
//
template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::faces_size_type
num_faces(const OPEN_MESH_CLASS& sm)
{
  return sm.n_faces();
}

template <typename K>
CGAL::Iterator_range<typename boost::graph_traits<OPEN_MESH_CLASS >::face_iterator>
faces(const OPEN_MESH_CLASS& sm)
{
  return CGAL::make_range(sm.faces_sbegin(), sm.faces_end());
}


template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
add_vertex(OPEN_MESH_CLASS& sm) {
  return sm.new_vertex();
}

  /*

// MutableGraph
// add a vertex with a default constructed property
template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
add_vertex(OPEN_MESH_CLASS& sm) {
  return sm.add_vertex(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_property_type());
}

template <typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor
add_vertex(const typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_property_type& p, OPEN_MESH_CLASS& sm) {
  return sm.add_vertex(p);
}

template <typename K>
void
clear_vertex(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor,
             OPEN_MESH_CLASS&) {
  CGAL_assert(false);
}

  */

template <typename K>
void
remove_vertex(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
              OPEN_MESH_CLASS& sm) {

  sm.request_face_status();
  sm.request_vertex_status();
  sm.request_halfedge_status();
  sm.set_halfedge_handle(v, typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor());
  sm.status(v).set_deleted(true);
}


template <typename K>
void
remove_edge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor u,
            typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v,
            OPEN_MESH_CLASS& sm)
{
  typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor e = edge(u, v, sm);
  remove_edge(e,sm);
}

template <typename K>
void
remove_edge(typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor e,
            OPEN_MESH_CLASS& sm)
{
  sm.request_face_status();
  sm.request_vertex_status();
  sm.request_halfedge_status();
  sm.request_edge_status();

  typedef typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor halfedge_descriptor;

  halfedge_descriptor h1 = halfedge(e,sm);
  halfedge_descriptor h2 = opposite(halfedge(e,sm),sm);
  sm.status(sm.edge_handle(h1)).set_deleted(true);
  sm.status(h1).set_deleted(true);
  sm.status(h2).set_deleted(true);

}


template <typename K>
void
remove_edge(typename boost::graph_traits<OPEN_MESH_CLASS >::edge_iterator eiter,
            OPEN_MESH_CLASS& sm)
{
  remove_edge(*eiter, sm);
}

template<typename K>
void
remove_face(typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor f,
            OPEN_MESH_CLASS& sm)
{

  sm.request_face_status();
  sm.request_vertex_status();
  sm.request_halfedge_status();

  set_halfedge(f, typename boost::graph_traits<OPEN_MESH_CLASS >::halfedge_descriptor(), sm);
  sm.status(f).set_deleted(true);
}

#if 0 // conflicts with function in Euler_operations.h
template<typename K>
std::pair<typename boost::graph_traits<OPEN_MESH_CLASS >::edge_descriptor,
          bool>
add_edge(typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v1,
         typename boost::graph_traits<OPEN_MESH_CLASS >::vertex_descriptor v2,
         OPEN_MESH_CLASS& sm) {

  return sm.new_edge(v1, v2);
}
#endif

template<typename K>
typename boost::graph_traits<OPEN_MESH_CLASS >::face_descriptor
add_face(OPEN_MESH_CLASS& sm)
{
  return sm.new_face();
}

} // namespace OpenMesh

namespace CGAL {

// Overload CGAL::clear function. PolyMesh_ArrayKernel behaves
// differently from other meshes. Calling clear does not affect the
// number of vertices, edges, or faces in the mesh. To get actual
// numbers it is necessary to first collect garbage. We add an
// overlaod to get consistent behavior.
template<typename K>
void clear(OPEN_MESH_CLASS& sm)
{
  sm.clear();
  sm.garbage_collection(true, true, true);
  CGAL_postcondition(num_edges(sm) == 0);
  CGAL_postcondition(num_vertices(sm) == 0);
  CGAL_postcondition(num_faces(sm) == 0);
}

//doesn't seem to work. Use BGL default IO functions instead.
//template<typename K>
//bool read_OFF(std::istream& is, OPEN_MESH_CLASS& sm)
//{
//  OpenMesh::IO::Options ropt;
//  return OpenMesh::IO::read_mesh(sm, is, ".OFF", ropt, false);
//}

//template<typename K>
//bool write_OFF(std::ostream& os, OPEN_MESH_CLASS& sm)
//{
//  return OpenMesh::IO::write_mesh(sm, os, ".OFF");
//}

}
#ifndef CGAL_NO_DEPRECATED_CODE
#include <CGAL/boost/graph/backward_compatibility_functions.h>

namespace boost {
  // The following functions were defined in the namespace boost
  using OpenMesh::vertices;
  using OpenMesh::edges;
  using OpenMesh::num_vertices;
  using OpenMesh::num_edges;
  using OpenMesh::out_edges;
  using OpenMesh::in_edges;
  using OpenMesh::target;
  using OpenMesh::source;
} // namespace boost
#endif //CGAL_NO_DEPRECATED_CODE

#if defined(BOOST_MSVC)
#  pragma warning(pop)
#endif

#undef OPEN_MESH_CLASS

