// Copyright (c) 2004 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_BACK_REFERENCE_040510_HPP
#define LUABIND_BACK_REFERENCE_040510_HPP

#include <luabind/config.hpp>
#include <luabind/lua_state_fwd.hpp>
#include <type_traits>

#if !defined(LUABIND_NO_RTTI) && !defined(LUABIND_WRAPPER_BASE_HPP_INCLUDED)
#include <luabind/wrapper_base.hpp>
#endif

#include <luabind/pointer_traits.hpp>

namespace luabind {
	struct wrap_base;

	namespace detail
	{
		template<class T>
		wrap_base const* get_back_reference_aux0(T const* p, std::true_type)
		{
			return dynamic_cast<wrap_base const*>(p);
		}

		template<class T>
		wrap_base const* get_back_reference_aux0(T const*, std::false_type)
		{
			return 0;
		}

		template<class T>
		wrap_base const* get_back_reference_aux1(T const* p)
		{
			return get_back_reference_aux0(p, std::is_polymorphic<T>());
		}

		template<class T>
		wrap_base const* get_back_reference_aux2(T const& x, std::true_type)
		{
			return get_back_reference_aux1(get_pointer(x));
		}

		template<class T>
		wrap_base const* get_back_reference_aux2(T const& x, std::false_type)
		{
			return get_back_reference_aux1(&x);
		}

		template<class T>
		wrap_base const* get_back_reference(T const& x)
		{
			return detail::get_back_reference_aux2(
				x
				, has_get_pointer<T>()
			);
		}

	} // namespace detail

	template<class T>
	bool get_back_reference(lua_State* L, T const& x)
	{
#ifndef LUABIND_NO_RTTI
		if(wrap_base const* w = detail::get_back_reference(x))
		{
			detail::wrap_access::ref(*w).get(L);
			return true;
		}
#endif
		return false;
	}

	template<class T>
	bool move_back_reference(lua_State* L, T const& x)
	{
#ifndef LUABIND_NO_RTTI
		if(wrap_base* w = const_cast<wrap_base*>(detail::get_back_reference(x)))
		{
			assert(detail::wrap_access::ref(*w).m_strong_ref.is_valid());
			detail::wrap_access::ref(*w).get(L);
			detail::wrap_access::ref(*w).m_strong_ref.reset();
			return true;
		}
#endif
		return false;
	}

} // namespace luabind

#endif // LUABIND_BACK_REFERENCE_040510_HPP

