//
// mp::multiplex
//
// 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_MULTIPLEX_H__
#define MP_MULTIPLEX_H__

#include "mp/event.h"
#include "mp/source.h"
#include "mp/zone.h"
#include <memory>

namespace mp {
namespace multiplex {


class handler;

class manager {
public:
	static void initialize();
	static void destroy();

public:
	template <typename Handler>
	static void add(int fd);
	
MP_ARGS_BEGIN
	template <typename Handler, MP_ARGS_TEMPLATE>
	static void add(int fd, MP_ARGS_PARAMS);
MP_ARGS_END

	static handler& data(int fd);

	static void send_data(int fd, const char* buf, size_t len);

	static int run();
	static void end();
	static bool is_end();

private:
	template <typename Handler>
	void add_impl(int fd);
	
MP_ARGS_BEGIN
	template <typename Handler, MP_ARGS_TEMPLATE>
	void add_impl(int fd, MP_ARGS_PARAMS);
MP_ARGS_END

	handler& data_impl(int fd);
	void send_data_impl(int fd, const char* buf, size_t len);
	//void send_message_impl(int fd, callback_message* msg);

	int run_impl();

private:
	class cb_t {
	public:
		cb_t(handler* h, short ev);
		~cb_t();
	public:
		short event() const;
		void event(short ev);
		handler& get();
	private:
		handler* m_handler;
		short m_event;
	private:
		char* m_wbuffer;
		size_t m_allocated;
		size_t m_used;
	public:
		void append_buffer(const char* buf, size_t len);
		void consume_buffer(size_t len);
		const char* wbuffer() const;
		size_t length() const;
		bool empty() const;
	};

	typedef event<cb_t> ev_t;
	ev_t m_ev;
	zone m_zone;

private:
	typedef std::vector<cb_t*> wswitch_ctx_t;
	wswitch_ctx_t m_wswitch_ctx;

private:
	void try_read(cb_t& cb);
	bool try_write(cb_t& cb);
	void rswitch(cb_t& cb);
	void wswitch(cb_t& cb);
	void close_connection(cb_t& cb);

private:
	volatile sig_atomic_t m_end_flag;

private:
	static std::auto_ptr<manager> s_instance;
	static manager& instance() { return *s_instance; }

public:
	manager();
	~manager();
};


class handler {
public:
	handler(int fd);
	virtual ~handler();
public:
	virtual void read_event() = 0;
	virtual void connected() {}
public:
	int fd() const
		{ return m_fd; }
	void send_data(const void* buf, size_t len)
		{ return manager::send_data(m_fd, buf, len); }
private:
	int m_fd;
private:
	handler();
	handler(const handler&);
};


inline void initialize()
{
	manager::initialize();
}

inline void destroy()
{
	manager::destroy();
}

inline int run()
{
	return manager::run();
}

inline void end()
{
	manager::end();
}

inline bool is_end()
{
	return manager::is_end();
}

template <typename Handler>
inline void add(int fd)
{
	manager::add<Handler>(fd);
}
	
MP_ARGS_BEGIN
template <typename Handler, MP_ARGS_TEMPLATE>
inline void add(int fd, MP_ARGS_PARAMS)
{
	manager::add<Handler, MP_ARGS_TYPES>(fd, MP_ARGS_FUNC);
}
MP_ARGS_END

inline void send_data(int fd, const void* buf, size_t len)
{
	manager::send_data(fd, buf, len);
}


template <typename T, typename R>
inline void submit(R (*func)(void*), T* obj)
{
	(*func)(obj);
}

MP_ARGS_BEGIN
template <typename T, typename R, MP_ARGS_TEMPLATE>
inline void submit(R (*func)(void*, MP_ARGS_PARAMS), T* obj, MP_ARGS_PARAMS)
{
	(*func)(obj, MP_ARGS_FUNC);
}
MP_ARGS_END


}  // namespace multiplex
}  // namespace mp

#include "mp/multiplex_impl.h"
#include "mp/multiplex/listen.h"
#include "mp/multiplex/timer.h"

#endif /* mp/multiplex.h */