/*
 *	DNN - Data News Network
 *
 *	by Stephane Chatty
 *
 *	Copyright 1993-1994
 *	Centre d'Etudes de la Navigation Aerienne (CENA)
 *
 *	Reactions.
 *
 *	$Id$
 *	$CurLog$
 */

#ifndef DnnReaction_H_
#define DnnReaction_H_

#ifdef __GNUG__
#pragma interface
#endif


#include "ccu/List.h"

class DnnTrigger;
class DnnEvent;

class DnnBaseReaction {
protected:
		DnnBaseReaction ();
	CcuListOf <DnnTrigger>	Triggers;
	CcuListOf <DnnTrigger>	Grabbed;

public:
virtual	~DnnBaseReaction ();
	void	SubscribeTo (DnnTrigger&);
	void	UnsubscribeTo (DnnTrigger&);
	void	Grab (DnnTrigger&);
	void	Release (DnnTrigger&);
virtual	void	Manage (DnnEvent&);
};


typedef void (*DnnHandlingFunction) (DnnEvent&);

class DnnReaction : public DnnBaseReaction {
protected:
	DnnHandlingFunction	Handler;

public:
		DnnReaction (DnnHandlingFunction);
		~DnnReaction ();
	void	Manage (DnnEvent&);
};


#define SpecializedReaction(R,S) \
class R : public DnnBaseReaction { \
protected: \
	S&	Body; \
	void	(S::*React)	(DnnEvent&); \
public: \
		R (S& s, void (S::*sc) (DnnEvent&)) : DnnBaseReaction (), Body (s), React (sc)	{} \
		~R ()	{} \
	void	Manage (DnnEvent& ev)	{ (Body.*React) (ev); } \
};

template <class T> class DnnReactionOf : public DnnBaseReaction {
protected:
	T&	Object;
	void	(T::*Reaction)	(DnnEvent&);

public:
		DnnReactionOf (T& o, void (T::*r) (DnnEvent&)) : DnnBaseReaction (), Object (o), Reaction (r)	{}
		~DnnReactionOf ()	{}
	void	Manage (DnnEvent& ev)	{ (Object.*Reaction) (ev); }
};

#endif	/* DnnReaction_H_ */