//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// This file is part of the Boost Graph Library
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
// Copyright (c) 2007-2015  GeometryFactory (France).  All rights reserved.
//
// $URL$
// $Id$
// SPDX-License-Identifier: BSL-1.0
//
// Author(s)     : Andreas Fabri, Fernando Cacciola, Jane Tournois

#ifndef CGAL_BOOST_GRAPH_NAMED_PARAMETERS_HELPERS_H
#define CGAL_BOOST_GRAPH_NAMED_PARAMETERS_HELPERS_H

#include <CGAL/boost/graph/named_function_params.h>

#include <CGAL/Kernel_traits.h>
#include <CGAL/Origin.h>

#include <CGAL/property_map.h>
#include <CGAL/boost/graph/properties.h>
#include <boost/mpl/if.hpp>

#include <boost/type_traits/is_same.hpp>
#include <boost/version.hpp>

namespace CGAL {
  //helper classes
  template<typename PolygonMesh, typename PropertyTag>
  class property_map_selector
  {
  public:
    typedef typename boost::graph_has_property<PolygonMesh, PropertyTag>::type Has_internal_pmap;
    typedef typename boost::mpl::if_c< Has_internal_pmap::value
                                       , typename boost::property_map<PolygonMesh, PropertyTag>::type
                                       , typename boost::cgal_no_property::type
                                       >::type type;
    typedef typename boost::mpl::if_c< Has_internal_pmap::value
                                       , typename boost::property_map<PolygonMesh, PropertyTag>::const_type
                                       , typename boost::cgal_no_property::const_type
                                       >::type const_type;

    type get_pmap(const PropertyTag& p, PolygonMesh& pmesh)
    {
      return get_impl(p, pmesh, Has_internal_pmap());
    }

    const_type get_const_pmap(const PropertyTag& p, const PolygonMesh& pmesh)
    {
      return get_const_pmap_impl(p, pmesh, Has_internal_pmap());
    }

  private:
    type get_impl(const PropertyTag&, PolygonMesh&, CGAL::Tag_false)
    {
      return type(); //boost::cgal_no_property::type
    }
    type get_impl(const PropertyTag& p, PolygonMesh& pmesh, CGAL::Tag_true)
    {
      return get(p, pmesh);
    }

    const_type get_const_pmap_impl(const PropertyTag&
                                   , const PolygonMesh&, CGAL::Tag_false)
    {
      return const_type(); //boost::cgal_no_property::type
    }
    const_type get_const_pmap_impl(const PropertyTag& p
                                   , const PolygonMesh& pmesh, CGAL::Tag_true)
    {
      return get(p, pmesh);
    }
  };

  template<typename PolygonMesh, typename PropertyTag>
  typename property_map_selector<PolygonMesh, PropertyTag>::type
  get_property_map(const PropertyTag& p, PolygonMesh& pmesh)
  {
    property_map_selector<PolygonMesh, PropertyTag> pms;
    return pms.get_pmap(p, pmesh);
  }

  template<typename PolygonMesh, typename PropertyTag>
  typename property_map_selector<PolygonMesh, PropertyTag>::const_type
  get_const_property_map(const PropertyTag& p, const PolygonMesh& pmesh)
  {
    property_map_selector<PolygonMesh, PropertyTag> pms;
    return pms.get_const_pmap(p, pmesh);
  }
// shortcut for accessing the value type of the property map
  template <class Graph, class Property>
  class property_map_value {
    typedef typename boost::property_map<Graph, Property>::const_type PMap;
  public:
    typedef typename boost::property_traits<PMap>::value_type type;
  };

  template<typename PolygonMesh, typename NamedParameters>
  class GetVertexPointMap
  {
    typedef typename property_map_selector<PolygonMesh, boost::vertex_point_t>::const_type
    DefaultVPMap_const;
    typedef typename property_map_selector<PolygonMesh, boost::vertex_point_t>::type
    DefaultVPMap;
  public:
    typedef typename boost::lookup_named_param_def<
    internal_np::vertex_point_t,
    NamedParameters,
    DefaultVPMap
    > ::type  type;
    typedef typename boost::lookup_named_param_def<
      internal_np::vertex_point_t,
      NamedParameters,
      DefaultVPMap_const
      > ::type  const_type;
  };

  template<typename PolygonMesh, typename NamedParameters>
  class GetK
  {
    typedef typename boost::property_traits<
      typename GetVertexPointMap<PolygonMesh, NamedParameters>::type
      >::value_type Point;
  public:
    typedef typename CGAL::Kernel_traits<Point>::Kernel Kernel;
  };

  template<typename PolygonMesh, typename NamedParameters = cgal_bgl_named_params<bool, internal_np::all_default_t> >
  class GetGeomTraits
  {
    typedef typename boost::graph_has_property<PolygonMesh, boost::vertex_point_t>::type
    Has_internal_pmap;
    struct Fake_GT {};//to be used if there is no internal vertex_point_map in PolygonMesh

    typedef typename boost::mpl::if_c< Has_internal_pmap::value
                                       , typename GetK<PolygonMesh, NamedParameters>::Kernel
                                       , Fake_GT
                                       >::type DefaultKernel;

  public:
    typedef typename boost::lookup_named_param_def <
    internal_np::geom_traits_t,
    NamedParameters,
    DefaultKernel
    > ::type  type;
  };

  template<typename PolygonMesh, typename NamedParameters>
  class GetFaceIndexMap
  {
    typedef typename property_map_selector<PolygonMesh, boost::face_index_t>::type DefaultMap;
    typedef typename property_map_selector<PolygonMesh, boost::face_index_t>::const_type DefaultMap_const;
  public:
    typedef typename boost::lookup_named_param_def <
    internal_np::face_index_t,
    NamedParameters,
    DefaultMap
    > ::type  type;
    typedef typename boost::lookup_named_param_def <
      internal_np::face_index_t,
      NamedParameters,
      DefaultMap_const
      > ::type  const_type;
    typedef typename boost::is_same<type, DefaultMap>::type Is_internal_map;
    typedef typename boost::is_same<const_type, DefaultMap_const>::type Is_internal_map_const;
  };

  template<typename PolygonMesh, typename NamedParameters>
  class GetVertexIndexMap
  {
    typedef typename property_map_selector<PolygonMesh, boost::vertex_index_t>::type DefaultMap;
  public:
    typedef typename boost::lookup_named_param_def <
    internal_np::vertex_index_t,
    NamedParameters,
    DefaultMap
    > ::type  type;
  };

  template<typename PolygonMesh, typename NamedParameters>
  class GetFaceNormalMap
  {
    struct DummyNormalPmap
    {
      typedef typename boost::graph_traits<PolygonMesh>::face_descriptor key_type;
      typedef typename GetGeomTraits<PolygonMesh, NamedParameters>::type::Vector_3 value_type;
      typedef value_type reference;
      typedef boost::readable_property_map_tag category;

      typedef DummyNormalPmap Self;
      friend reference get(const Self&, const key_type&) { return CGAL::NULL_VECTOR; }
    };

  public:
    typedef DummyNormalPmap NoMap;
    typedef typename boost::lookup_named_param_def <
      internal_np::face_normal_t,
      NamedParameters,
      DummyNormalPmap//default
      > ::type  type;
  };

  template<typename NamedParameters, typename DefaultSolver>
  class GetSolver
  {
  public:
    typedef typename boost::lookup_named_param_def <
    internal_np::sparse_linear_solver_t,
    NamedParameters,
    DefaultSolver
    > ::type type;
  };
} //namespace CGAL


#endif // CGAL_BOOST_GRAPH_NAMED_PARAMETERS_HELPERS_H