//
// mp::callback_message
//
// Copyright (C) 2008 FURUHASHI Sadayuki
//
//    Licensed under the Apache License, Version 2.0 (the "License");
//    you may not use this file except in compliance with the License.
//    You may obtain a copy of the License at
//
//        http://www.apache.org/licenses/LICENSE-2.0
//
//    Unless required by applicable law or agreed to in writing, software
//    distributed under the License is distributed on an "AS IS" BASIS,
//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//    See the License for the specific language governing permissions and
//    limitations under the License.
//

#ifndef MP_CALLBACK_MESSAGE_H__
#define MP_CALLBACK_MESSAGE_H__

#include "mp/object_callback.h"

namespace mp {


struct callback_message {
	callback_message() {}
	virtual ~callback_message() {}
	virtual void operator() () = 0;
MP_ARGS_BEGIN
	template <typename T, typename R, MP_ARGS_TEMPLATE>
	static inline callback_message* create(R (*func)(void*, MP_ARGS_PARAMS), T* obj, MP_ARGS_PARAMS);
MP_ARGS_END
private:
	callback_message(const callback_message&);
};


template <typename Signature>
struct callback_message_impl;

template <typename R>
struct callback_message_impl<R ()> : public callback_message
{
	callback_message_impl(R (*func)(void*), void* obj) :
		m_func(func), m_obj(obj) {}
	R operator() ()
		{ return (*m_func)(m_obj); }
private:
	R (*m_func)(void*);
	void* m_obj;
};

MP_ARGS_BEGIN
template <typename R, MP_ARGS_TEMPLATE>
struct callback_message_impl<R (MP_ARGS_PARAMS)> : public callback_message
{
	callback_message_impl(R (*func)(void*, MP_ARGS_PARAMS), void* obj, MP_ARGS_PARAMS) :
		m_func(func),
		m_obj(obj),
MP_ARGS_ITERATOR_BEGIN
		m_[MP_ARGS_ITERATOR](MP_ARGS_ITERATOR_PARAM)MP_ARGS_ITERATOR_LAST_COLON
MP_ARGS_ITERATOR_END
		{}
	R operator() ()
	{
		return (*m_func)(m_obj,
MP_ARGS_ITERATOR_BEGIN
			m_[MP_ARGS_ITERATOR]MP_ARGS_ITERATOR_LAST_COLON
MP_ARGS_ITERATOR_END
		);
	}

private:
	template <typename T, R (T::*MemFun)()>
	static R mem_fun(void* obj)
	{
		return (reinterpret_cast<T*>(obj)->*MemFun)();
	}

private:
	R (*m_func)(void*, MP_ARGS_PARAMS);
	void* m_obj;
MP_ARGS_ITERATOR_BEGIN
	MP_ARGS_ITERATOR_TYPE m_[MP_ARGS_ITERATOR];
MP_ARGS_ITERATOR_END
};
MP_ARGS_END


MP_ARGS_BEGIN
template <typename T, typename R, MP_ARGS_TEMPLATE>
callback_message* callback_message::create(R (*func)(void*, MP_ARGS_PARAMS), T* obj, MP_ARGS_PARAMS)
{
	return new callback_message_impl<R (MP_ARGS_PARAMS)>(func,
		reinterpret_cast<void*>(obj), MP_ARGS_FUNC);
}
MP_ARGS_END


}  // namespace mp

#endif /* mp/callback_message.h */