/*]  Copyright (c) 2009-2011, Charles McGarvey  [*****************************
**]  All rights reserved.
*
* Distributable under the terms and conditions of the 2-clause BSD license;
* see the file COPYING for a complete text of the license.
*
*****************************************************************************/

#ifndef _MOOF_DISPATCH_HH_
#define _MOOF_DISPATCH_HH_

#include <string>

#include <boost/bind.hpp>
#include <boost/function.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/weak_ptr.hpp>


/**
 * \file dispatcher.hh
 * Classes that deal with message dispatching.
 */

namespace moof {


/**
 * Dispatcher of messages to interested parties.
 */
class dispatcher
{
	class impl;
	boost::shared_ptr<impl> impl_;

	void remove_target(unsigned id);

public:

	class handle
	{
	public:

		handle() :
			id_(0) {}

		handle(boost::weak_ptr<impl> dispatcher, unsigned id) :
			dispatcher_(dispatcher),
			id_(id) {}

		handle(const handle& handle) :
			dispatcher_(handle.dispatcher_),
			id_(handle.id_)
		{
			handle.id_ = 0;
		}

		~handle()
		{
			clear();
		}

		handle& operator = (const handle& handle)
		{
			clear();
			dispatcher_ = handle.dispatcher_;
			id_ = handle.id_;
			handle.id_ = 0;
			return *this;
		}

		unsigned id() const
		{
			return id_;
		}

		void clear();
	
	private:

		boost::weak_ptr<impl>	dispatcher_;
		mutable unsigned	id_;
	};

	typedef boost::function<void(void)> function;

	dispatcher();

	handle add_target(const std::string& event, const function& callback);
	handle add_target(const std::string& event, const function& callback,
			handle handle);

	void dispatch(const std::string& event);

	static dispatcher& global();
};


} // namespace moof

#endif // _MOOF_DISPATCH_HH_