//  (C) Copyright Jeremy Siek 2004
//  (C) Copyright Thomas Claveirole 2010
//  (C) Copyright Ignacy Gawedzki 2010
//  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_GRAPH_DETAIL_CONTAINER_TRAITS_H
#define BOOST_GRAPH_DETAIL_CONTAINER_TRAITS_H

// Sure would be nice to be able to forward declare these
// instead of pulling in all the headers. Too bad that
// is not legal. There ought to be a standard <stlfwd> header. -JGS

#include <boost/next_prior.hpp>

#include <algorithm> // for std::remove
#include <utility>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <boost/unordered_set.hpp>
#include <boost/unordered_map.hpp>

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
#include <unordered_set>
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
#include <unordered_map>
#endif

#ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
#define BOOST_PENDING_FWD_TYPE(type) const type&
#define BOOST_PENDING_FWD_VALUE(type, var) (var)
#else
#define BOOST_PENDING_FWD_TYPE(type) type&&
#define BOOST_PENDING_FWD_VALUE(type, var) (std::forward< type >((var)))
#endif

// The content of this file is in 'graph_detail' because otherwise
// there will be name clashes with
// sandbox/boost/sequence_algo/container_traits.hpp
// The 'detail' subnamespace will still cause problems.
namespace boost
{
namespace graph_detail
{

    //======================================================================
    // Container Category Tags
    //
    //   They use virtual inheritance because there are lots of
    //   inheritance diamonds.

    struct container_tag
    {
    };
    struct forward_container_tag : virtual public container_tag
    {
    };
    struct reversible_container_tag : virtual public forward_container_tag
    {
    };
    struct random_access_container_tag : virtual public reversible_container_tag
    {
    };

    struct sequence_tag : virtual public forward_container_tag
    {
    };

    struct associative_container_tag : virtual public forward_container_tag
    {
    };

    struct sorted_associative_container_tag
    : virtual public associative_container_tag,
      virtual public reversible_container_tag
    {
    };

    struct front_insertion_sequence_tag : virtual public sequence_tag
    {
    };
    struct back_insertion_sequence_tag : virtual public sequence_tag
    {
    };

    struct unique_associative_container_tag
    : virtual public associative_container_tag
    {
    };
    struct multiple_associative_container_tag
    : virtual public associative_container_tag
    {
    };
    struct simple_associative_container_tag
    : virtual public associative_container_tag
    {
    };
    struct pair_associative_container_tag
    : virtual public associative_container_tag
    {
    };

    //======================================================================
    // Iterator Stability Tags
    //
    // Do mutating operations such as insert/erase/resize invalidate all
    // outstanding iterators?

    struct stable_tag
    {
    };
    struct unstable_tag
    {
    };

    //======================================================================
    // Container Traits Class and container_category() function

    // don't use this unless there is partial specialization
    template < class Container > struct container_traits
    {
        typedef typename Container::category category;
        typedef typename Container::iterator_stability iterator_stability;
    };

    // Use this as a compile-time assertion that X is stable
    inline void require_stable(stable_tag) {}

    // std::vector
    struct vector_tag : virtual public random_access_container_tag,
                        virtual public back_insertion_sequence_tag
    {
    };

    template < class T, class Alloc >
    vector_tag container_category(const std::vector< T, Alloc >&)
    {
        return vector_tag();
    }

    template < class T, class Alloc >
    unstable_tag iterator_stability(const std::vector< T, Alloc >&)
    {
        return unstable_tag();
    }

    template < class T, class Alloc >
    struct container_traits< std::vector< T, Alloc > >
    {
        typedef vector_tag category;
        typedef unstable_tag iterator_stability;
    };

    // std::list
    struct list_tag : virtual public reversible_container_tag,
                      virtual public back_insertion_sequence_tag
    // this causes problems for push_dispatch...
    //    virtual public front_insertion_sequence_tag
    {
    };

    template < class T, class Alloc >
    list_tag container_category(const std::list< T, Alloc >&)
    {
        return list_tag();
    }

    template < class T, class Alloc >
    stable_tag iterator_stability(const std::list< T, Alloc >&)
    {
        return stable_tag();
    }

    template < class T, class Alloc >
    struct container_traits< std::list< T, Alloc > >
    {
        typedef list_tag category;
        typedef stable_tag iterator_stability;
    };

    // std::set
    struct set_tag : virtual public sorted_associative_container_tag,
                     virtual public simple_associative_container_tag,
                     virtual public unique_associative_container_tag
    {
    };

    template < class Key, class Cmp, class Alloc >
    set_tag container_category(const std::set< Key, Cmp, Alloc >&)
    {
        return set_tag();
    }

    template < class Key, class Cmp, class Alloc >
    stable_tag iterator_stability(const std::set< Key, Cmp, Alloc >&)
    {
        return stable_tag();
    }

    template < class Key, class Cmp, class Alloc >
    struct container_traits< std::set< Key, Cmp, Alloc > >
    {
        typedef set_tag category;
        typedef stable_tag iterator_stability;
    };

    // std::multiset
    struct multiset_tag : virtual public sorted_associative_container_tag,
                          virtual public simple_associative_container_tag,
                          virtual public multiple_associative_container_tag
    {
    };

    template < class Key, class Cmp, class Alloc >
    multiset_tag container_category(const std::multiset< Key, Cmp, Alloc >&)
    {
        return multiset_tag();
    }

    template < class Key, class Cmp, class Alloc >
    stable_tag iterator_stability(const std::multiset< Key, Cmp, Alloc >&)
    {
        return stable_tag();
    }

    template < class Key, class Cmp, class Alloc >
    struct container_traits< std::multiset< Key, Cmp, Alloc > >
    {
        typedef multiset_tag category;
        typedef stable_tag iterator_stability;
    };

    // deque

    // std::map
    struct map_tag : virtual public sorted_associative_container_tag,
                     virtual public pair_associative_container_tag,
                     virtual public unique_associative_container_tag
    {
    };

    template < class Key, class T, class Cmp, class Alloc >
    struct container_traits< std::map< Key, T, Cmp, Alloc > >
    {
        typedef map_tag category;
        typedef stable_tag iterator_stability;
    };

    template < class Key, class T, class Cmp, class Alloc >
    map_tag container_category(const std::map< Key, T, Cmp, Alloc >&)
    {
        return map_tag();
    }

    template < class Key, class T, class Cmp, class Alloc >
    stable_tag iterator_stability(const std::map< Key, T, Cmp, Alloc >&)
    {
        return stable_tag();
    }

    // std::multimap
    struct multimap_tag : virtual public sorted_associative_container_tag,
                          virtual public pair_associative_container_tag,
                          virtual public multiple_associative_container_tag
    {
    };

    template < class Key, class T, class Cmp, class Alloc >
    struct container_traits< std::multimap< Key, T, Cmp, Alloc > >
    {
        typedef multimap_tag category;
        typedef stable_tag iterator_stability;
    };

    template < class Key, class T, class Cmp, class Alloc >
    multimap_tag container_category(const std::multimap< Key, T, Cmp, Alloc >&)
    {
        return multimap_tag();
    }

    template < class Key, class T, class Cmp, class Alloc >
    stable_tag iterator_stability(const std::multimap< Key, T, Cmp, Alloc >&)
    {
        return stable_tag();
    }

    // hash_set, hash_map

    struct unordered_set_tag : virtual public simple_associative_container_tag,
                               virtual public unique_associative_container_tag
    {
    };

    struct unordered_multiset_tag
    : virtual public simple_associative_container_tag,
      virtual public multiple_associative_container_tag
    {
    };

    struct unordered_map_tag : virtual public pair_associative_container_tag,
                               virtual public unique_associative_container_tag
    {
    };

    struct unordered_multimap_tag
    : virtual public pair_associative_container_tag,
      virtual public multiple_associative_container_tag
    {
    };

    template < class Key, class Eq, class Hash, class Alloc >
    struct container_traits< boost::unordered_set< Key, Eq, Hash, Alloc > >
    {
        typedef unordered_set_tag category;
        typedef unstable_tag iterator_stability;
    };
    template < class Key, class T, class Eq, class Hash, class Alloc >
    struct container_traits< boost::unordered_map< Key, T, Eq, Hash, Alloc > >
    {
        typedef unordered_map_tag category;
        typedef unstable_tag iterator_stability;
    };
    template < class Key, class Eq, class Hash, class Alloc >
    struct container_traits< boost::unordered_multiset< Key, Eq, Hash, Alloc > >
    {
        typedef unordered_multiset_tag category;
        typedef unstable_tag iterator_stability;
    };
    template < class Key, class T, class Eq, class Hash, class Alloc >
    struct container_traits<
        boost::unordered_multimap< Key, T, Eq, Hash, Alloc > >
    {
        typedef unordered_multimap_tag category;
        typedef unstable_tag iterator_stability;
    };

    template < class Key, class Eq, class Hash, class Alloc >
    unordered_set_tag container_category(
        const boost::unordered_set< Key, Eq, Hash, Alloc >&)
    {
        return unordered_set_tag();
    }

    template < class Key, class T, class Eq, class Hash, class Alloc >
    unordered_map_tag container_category(
        const boost::unordered_map< Key, T, Eq, Hash, Alloc >&)
    {
        return unordered_map_tag();
    }

    template < class Key, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const boost::unordered_set< Key, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }

    template < class Key, class T, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const boost::unordered_map< Key, T, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }
    template < class Key, class Eq, class Hash, class Alloc >
    unordered_multiset_tag container_category(
        const boost::unordered_multiset< Key, Eq, Hash, Alloc >&)
    {
        return unordered_multiset_tag();
    }

    template < class Key, class T, class Eq, class Hash, class Alloc >
    unordered_multimap_tag container_category(
        const boost::unordered_multimap< Key, T, Eq, Hash, Alloc >&)
    {
        return unordered_multimap_tag();
    }

    template < class Key, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const boost::unordered_multiset< Key, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }

    template < class Key, class T, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const boost::unordered_multimap< Key, T, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    struct container_traits< std::unordered_set< Key, Eq, Hash, Alloc > >
    {
        typedef unordered_set_tag category;
        typedef unstable_tag iterator_stability;
    };
#endif
#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    struct container_traits< std::unordered_map< Key, T, Eq, Hash, Alloc > >
    {
        typedef unordered_map_tag category;
        typedef unstable_tag iterator_stability;
    };
#endif
#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    struct container_traits< std::unordered_multiset< Key, Eq, Hash, Alloc > >
    {
        typedef unordered_multiset_tag category;
        typedef unstable_tag iterator_stability;
    };
#endif
#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    struct container_traits<
        std::unordered_multimap< Key, T, Eq, Hash, Alloc > >
    {
        typedef unordered_multimap_tag category;
        typedef unstable_tag iterator_stability;
    };
#endif
#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    unordered_set_tag container_category(
        const std::unordered_set< Key, Eq, Hash, Alloc >&)
    {
        return unordered_set_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    unordered_map_tag container_category(
        const std::unordered_map< Key, T, Eq, Hash, Alloc >&)
    {
        return unordered_map_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const std::unordered_set< Key, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const std::unordered_map< Key, T, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }
#endif
#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    unordered_multiset_tag container_category(
        const std::unordered_multiset< Key, Eq, Hash, Alloc >&)
    {
        return unordered_multiset_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    unordered_multimap_tag container_category(
        const std::unordered_multimap< Key, T, Eq, Hash, Alloc >&)
    {
        return unordered_multimap_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_SET
    template < class Key, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const std::unordered_multiset< Key, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }
#endif

#ifndef BOOST_NO_CXX11_HDR_UNORDERED_MAP
    template < class Key, class T, class Eq, class Hash, class Alloc >
    unstable_tag iterator_stability(
        const std::unordered_multimap< Key, T, Eq, Hash, Alloc >&)
    {
        return unstable_tag();
    }
#endif

    //===========================================================================
    // Generalized Container Functions

    // Erase
    template < class Sequence, class T >
    void erase_dispatch(Sequence& c, const T& x, sequence_tag)
    {
        c.erase(std::remove(c.begin(), c.end(), x), c.end());
    }

    template < class AssociativeContainer, class T >
    void erase_dispatch(
        AssociativeContainer& c, const T& x, associative_container_tag)
    {
        c.erase(x);
    }
    template < class Container, class T > void erase(Container& c, const T& x)
    {
        erase_dispatch(c, x, container_category(c));
    }

    // Erase If
    template < class Sequence, class Predicate, class IteratorStability >
    void erase_if_dispatch(
        Sequence& c, Predicate p, sequence_tag, IteratorStability)
    {
#if 0
    c.erase(std::remove_if(c.begin(), c.end(), p), c.end());
#else
        if (!c.empty())
            c.erase(std::remove_if(c.begin(), c.end(), p), c.end());
#endif
    }
    template < class AssociativeContainer, class Predicate >
    void erase_if_dispatch(AssociativeContainer& c, Predicate p,
        associative_container_tag, stable_tag)
    {
        typename AssociativeContainer::iterator i, next;
        for (i = next = c.begin(); next != c.end(); i = next)
        {
            ++next;
            if (p(*i))
                c.erase(i);
        }
    }
    template < class AssociativeContainer, class Predicate >
    void erase_if_dispatch(AssociativeContainer& c, Predicate p,
        associative_container_tag, unstable_tag)
    {
        // This method is really slow, so hopefully we won't have any
        // associative containers with unstable iterators!
        // Is there a better way to do this?
        typename AssociativeContainer::iterator i;
        typename AssociativeContainer::size_type n = c.size();
        while (n--)
            for (i = c.begin(); i != c.end(); ++i)
                if (p(*i))
                {
                    c.erase(i);
                    break;
                }
    }
    template < class Container, class Predicate >
    void erase_if(Container& c, Predicate p)
    {
        erase_if_dispatch(c, p, container_category(c), iterator_stability(c));
    }

    // Push
    template < class Container, class T >
    std::pair< typename Container::iterator, bool > push_dispatch(
        Container& c, BOOST_PENDING_FWD_TYPE(T) v, back_insertion_sequence_tag)
    {
        c.push_back(BOOST_PENDING_FWD_VALUE(T, v));
        return std::make_pair(boost::prior(c.end()), true);
    }

    template < class Container, class T >
    std::pair< typename Container::iterator, bool > push_dispatch(
        Container& c, BOOST_PENDING_FWD_TYPE(T) v, front_insertion_sequence_tag)
    {
        c.push_front(BOOST_PENDING_FWD_VALUE(T, v));
        return std::make_pair(c.begin(), true);
    }

    template < class AssociativeContainer, class T >
    std::pair< typename AssociativeContainer::iterator, bool > push_dispatch(
        AssociativeContainer& c, BOOST_PENDING_FWD_TYPE(T) v,
        unique_associative_container_tag)
    {
        return c.insert(BOOST_PENDING_FWD_VALUE(T, v));
    }

    template < class AssociativeContainer, class T >
    std::pair< typename AssociativeContainer::iterator, bool > push_dispatch(
        AssociativeContainer& c, BOOST_PENDING_FWD_TYPE(T) v,
        multiple_associative_container_tag)
    {
        return std::make_pair(c.insert(BOOST_PENDING_FWD_VALUE(T, v)), true);
    }

    template < class Container, class T >
    std::pair< typename Container::iterator, bool > push(
        Container& c, BOOST_PENDING_FWD_TYPE(T) v)
    {
        return push_dispatch(
            c, BOOST_PENDING_FWD_VALUE(T, v), container_category(c));
    }

    // Find
    template < class Container, class Value >
    typename Container::iterator find_dispatch(
        Container& c, const Value& value, container_tag)
    {
        return std::find(c.begin(), c.end(), value);
    }

    template < class AssociativeContainer, class Value >
    typename AssociativeContainer::iterator find_dispatch(
        AssociativeContainer& c, const Value& value, associative_container_tag)
    {
        return c.find(value);
    }

    template < class Container, class Value >
    typename Container::iterator find(Container& c, const Value& value)
    {
        return find_dispatch(c, value, graph_detail::container_category(c));
    }

    // Find (const versions)
    template < class Container, class Value >
    typename Container::const_iterator find_dispatch(
        const Container& c, const Value& value, container_tag)
    {
        return std::find(c.begin(), c.end(), value);
    }

    template < class AssociativeContainer, class Value >
    typename AssociativeContainer::const_iterator find_dispatch(
        const AssociativeContainer& c, const Value& value,
        associative_container_tag)
    {
        return c.find(value);
    }

    template < class Container, class Value >
    typename Container::const_iterator find(
        const Container& c, const Value& value)
    {
        return find_dispatch(c, value, graph_detail::container_category(c));
    }

    // Equal range
#if 0
  // Make the dispatch fail if c is not an Associative Container (and thus
  // doesn't have equal_range unless it is sorted, which we cannot check
  // statically and is not typically true for BGL's uses of this function).
  template <class Container,
            class LessThanComparable>
  std::pair<typename Container::iterator, typename Container::iterator>
  equal_range_dispatch(Container& c,
                       const LessThanComparable& value,
                       container_tag)
  {
    // c must be sorted for std::equal_range to behave properly.
    return std::equal_range(c.begin(), c.end(), value);
  }
#endif

    template < class AssociativeContainer, class Value >
    std::pair< typename AssociativeContainer::iterator,
        typename AssociativeContainer::iterator >
    equal_range_dispatch(
        AssociativeContainer& c, const Value& value, associative_container_tag)
    {
        return c.equal_range(value);
    }

    template < class Container, class Value >
    std::pair< typename Container::iterator, typename Container::iterator >
    equal_range(Container& c, const Value& value)
    {
        return equal_range_dispatch(
            c, value, graph_detail::container_category(c));
    }

}
} // namespace boost::graph_detail

#undef BOOST_PENDING_FWD_TYPE
#undef BOOST_PENDING_FWD_VALUE

#endif // BOOST_GRAPH_DETAIL_CONTAINER_TRAITS_H