//=======================================================================

// Copyright 2002 Indiana University.

// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek

//

// 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)

//=======================================================================

#ifndef BOOST_ADJACENCY_ITERATOR_HPP

#define BOOST_ADJACENCY_ITERATOR_HPP

#include <boost/iterator/iterator_adaptor.hpp>

#include <boost/graph/graph_traits.hpp>

namespace boost

{

  template <class Graph, class Vertex, class OutEdgeIter, class Difference>

  struct adjacency_iterator

    : iterator_adaptor<

          adjacency_iterator<Graph,Vertex,OutEdgeIter,Difference>

        , OutEdgeIter

        , Vertex

        , use_default

        , Vertex

        , Difference

      >

  {

      typedef iterator_adaptor<

          adjacency_iterator<Graph,Vertex,OutEdgeIter,Difference>

        , OutEdgeIter

        , Vertex

        , use_default

        , Vertex

        , Difference

      > super_t;

      inline adjacency_iterator() {}

      inline adjacency_iterator(OutEdgeIter const& i, const Graph* g) : super_t(i), m_g(g) { }

      inline Vertex

      dereference() const

        { return target(*this->base(), *m_g); }

      const Graph* m_g;

  };

  template <class Graph,

            class Vertex = typename graph_traits<Graph>::vertex_descriptor,

            class OutEdgeIter=typename graph_traits<Graph>::out_edge_iterator>

  class adjacency_iterator_generator

  {

    typedef typename boost::detail::iterator_traits<OutEdgeIter>

      ::difference_type difference_type;

  public:

      typedef adjacency_iterator<Graph,Vertex,OutEdgeIter,difference_type> type;

  };

  template <class Graph, class Vertex, class InEdgeIter, class Difference>

  struct inv_adjacency_iterator

    : iterator_adaptor<

          inv_adjacency_iterator<Graph,Vertex,InEdgeIter,Difference>

        , InEdgeIter

        , Vertex

        , use_default

        , Vertex

        , Difference

      >

    {

      typedef iterator_adaptor<

                  inv_adjacency_iterator<Graph,Vertex,InEdgeIter,Difference>

                , InEdgeIter

                , Vertex

                , use_default

                , Vertex

                , Difference

              > super_t;

      inline inv_adjacency_iterator() { }

      inline inv_adjacency_iterator(InEdgeIter const& i, const Graph* g) : super_t(i), m_g(g) { }

      inline Vertex

      dereference() const

        { return source(*this->base(), *m_g); }

      const Graph* m_g;

    };

  template <class Graph,

            class Vertex = typename graph_traits<Graph>::vertex_descriptor,

            class InEdgeIter = typename graph_traits<Graph>::in_edge_iterator>

  class inv_adjacency_iterator_generator {

    typedef typename boost::detail::iterator_traits<InEdgeIter>

      ::difference_type difference_type;

  public:

      typedef inv_adjacency_iterator<Graph, Vertex, InEdgeIter, difference_type> type;

  };

} // namespace boost

#endif // BOOST_DETAIL_ADJACENCY_ITERATOR_HPP