// Copyright (c) 2003 Daniel Wallin and Arvid Norberg

// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
// ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
// OR OTHER DEALINGS IN THE SOFTWARE.


#ifndef LUABIND_ADOPT_POLICY_HPP_INCLUDED
#define LUABIND_ADOPT_POLICY_HPP_INCLUDED

#include <luabind/back_reference_fwd.hpp>
#include <luabind/config.hpp>
#include <luabind/detail/policy.hpp>
#include <luabind/wrapper_base.hpp>

#include <boost/type_traits/is_polymorphic.hpp>

namespace luabind { namespace detail
{
    template <class T>
    void adjust_backref_ownership(T* ptr, mpl::true_)
    {
        if (wrap_base* p = dynamic_cast<wrap_base*>(ptr))
        {
            wrapped_self_t& wrapper = wrap_access::ref(*p);
            wrapper.get(wrapper.state());
            wrapper.m_strong_ref.pop(wrapper.state());
        }
    }

    inline void adjust_backref_ownership(void*, mpl::false_)
    {}

    template <class Pointer, class Direction = lua_to_cpp>
    struct adopt_pointer : pointer_converter
    {
        typedef adopt_pointer type;

        int consumed_args() const
        {
            return 1;
        }

        template<class T>
        T* apply(lua_State* L, by_pointer<T>, int index)
        {
            T* ptr = pointer_converter::apply(
                L, LUABIND_DECORATE_TYPE(T*), index);

            object_rep* obj = static_cast<object_rep*>(
                lua_touserdata(L, index));
            obj->release();

            adjust_backref_ownership(ptr, boost::is_polymorphic<T>());

            return ptr;
        }

        template<class T>
        int match(lua_State* L, by_pointer<T>, int index)
        {
            return pointer_converter::match(
                L, LUABIND_DECORATE_TYPE(T*), index);
        }

        template<class T>
        void converter_postcall(lua_State*, T, int) {}
    };

    template <class Pointer, class T>
    struct pointer_or_default
    {
        typedef Pointer type;
    };

    template <class T>
    struct pointer_or_default<void, T>
    {
#ifdef LUABIND_USE_CXX11
        typedef std::unique_ptr<T> type;
#else
        typedef std::auto_ptr<T> type;
#endif
    };

    template <class Pointer>
    struct adopt_pointer<Pointer, cpp_to_lua>
    {
        typedef adopt_pointer type;

        template<class T>
        void apply(lua_State* L, T* ptr)
        {
            if (ptr == 0)
            {
                lua_pushnil(L);
                return;
            }

            // if there is a back_reference, then the
            // ownership will be removed from the
            // back reference and put on the lua stack.
            if (luabind::move_back_reference(L, ptr))
                return;

            typedef typename pointer_or_default<Pointer, T>::type
                pointer_type;

            make_instance(L, pointer_type(ptr));
        }
    };

    template <int N, class Pointer = void>
    struct adopt_policy : conversion_policy<N>
    {
//      BOOST_STATIC_CONSTANT(int, index = N);

        static void precall(lua_State*, const index_map&) {}
        static void postcall(lua_State*, const index_map&) {}

        struct only_accepts_nonconst_pointers {};

        template<class T, class Direction>
        struct apply
        {
            typedef luabind::detail::is_nonconst_pointer<T> is_nonconst_p;
            typedef typename boost::mpl::if_<
                is_nonconst_p
              , adopt_pointer<Pointer, Direction>
              , only_accepts_nonconst_pointers
            >::type type;
        };
    };

}}

namespace luabind
{
    template<int N>
    detail::policy_cons<detail::adopt_policy<N>, detail::null_type>
    adopt(LUABIND_PLACEHOLDER_ARG(N))
    {
        return detail::policy_cons<detail::adopt_policy<N>, detail::null_type>();
    }

    template <class Pointer, int N>
    detail::policy_cons<detail::adopt_policy<N, Pointer>, detail::null_type>
    adopt(LUABIND_PLACEHOLDER_ARG(N))
    {
        return detail::policy_cons<detail::adopt_policy<N, Pointer>, detail::null_type>();
    }
}

#endif // LUABIND_ADOPT_POLICY_HPP_INCLUDE
