myvtm/Framework/Common/SpFSM.h

#ifndef __SPFSM_H
#define __SPFSM_H

#pragma once

#include "SpBase.h"
#include "ListEntry.h"

#ifndef PARAM_SIZE_DEFINED
#define PARAM_SIZE_DEFINED

#ifdef _WIN32
typedef int param_size_t;
#else
#if (defined(__x86_64__) || defined(__aarch64__))
typedef intptr_t param_size_t;
#elif defined(__i386__)
typedef int param_size_t;
#else
typedef intptr_t param_size_t;
#endif
#endif //_WIN32

#endif // !PARAM_SIZE_DEFINED

/** finite state machine */

enum FSMEventEnum
{
	EVT_INTERNAL, // internal usage
	EVT_TIMER, // timer evt
	EVT_USER, // use defin Event must from here
};

#define FSM_STATE_INIT -1 // the initial state of the FSM
#define FSM_STATE_EXIT -2 // the exit state of the FSM

struct FSMEvent
{
	int iEvt;
	param_size_t param1;
	param_size_t param2;
	
	FSMEvent(int evt) 
		: m_ref_cnt(1)
		, iEvt(evt)
		,param1(-1) /** NOTICES!! maybe make some noise for real online FSM [5/26/2020 Gifur] */
		,param2(-1) /** NOTICES!! maybe make some noise for real online FSM [5/26/2020 Gifur] */
		, m_bHandled(FALSE)
	{
		m_entry.Flink = m_entry.Blink = &m_entry;
	}
	
	virtual ~FSMEvent() {}

	void IncRef() { InterlockedIncrement(&m_ref_cnt); }
	void DecRef() { if (0 == InterlockedDecrement(&m_ref_cnt)) {delete this;} }
	
	void SetHandled(BOOL bHandled = TRUE) { m_bHandled = bHandled; }
	BOOL IsHandled() { return m_bHandled; }
	virtual void OnUnhandled() {}

private:
	BOOL m_bHandled;
	LONG m_ref_cnt;
	LIST_ENTRY m_entry;
	friend class FSMBase;
};

template<class T>
struct FSMStateEntryT
{
	int id;
	const char *pszName;
	void *pUserData;
	void (T::*pOnEntry)();
	void (T::*pOnExit)();
	unsigned int (T::*pOnEvent)(FSMEvent *e);
};

struct FSMRuleEntry
{
	int src_state;
	int dst_state;
	int evt;
	unsigned int result_start;
	unsigned int result_end;
};

struct IFSMStateHooker
{
	virtual void OnStateTrans(int iSrcState, int iDstState)=0;
};

class SPBASE_API FSMBase
{
public:
	FSMBase();
	virtual ~FSMBase();

	ErrorCodeEnum Init(CEntityBase *pEntity); // try start the state machine
	ErrorCodeEnum PostExitEvent();		// active close FSM, force it into FSM_STATE_EXIT, so OnExit() could be called

	CEntityBase *GetEntityBase() { return m_pEntity; }

	void PostEventLIFO(FSMEvent *e);
	void PostEventFIFO(FSMEvent *e);

	ErrorCodeEnum ScheduleTimer(int iTimerId, unsigned int timeout); // iTimerId user define, one shot timer
	ErrorCodeEnum CancelTimer(int iTimerId);

	void AddStateHooker(IFSMStateHooker *pHooker);
	void RemoveStateHooker(IFSMStateHooker *pHooker);

	virtual int GetInitState() = 0;

	virtual ErrorCodeEnum OnInit() { return Error_Succeed; }
	virtual ErrorCodeEnum OnExit() { return Error_Succeed; }

	virtual void OnStateEntry(int state)=0;
	virtual void OnStateExit(int state)=0;
	virtual unsigned int OnStateEvent(FSMEvent *e)=0;
	virtual int MatchRule(int state, int evt, unsigned int rc)=0;
	virtual BOOL FindStateEvent(int evt)=0;

private:
	void Trans(int next);

#ifdef _WIN32
#if (!defined(SPABASE_LINKED_AS_STATIC_LIBRARY) && !defined(SPBASE_EXPORTS))
private:
#else
public:
#endif
#else 
public:
#endif //_WIN32

	void __ProcessEvent(FSMEvent *e);

protected:
	int m_iState;
	CEntityBase *m_pEntity;

private:
	void OnHook(int iSrcState, int iDstState);
	enum {MAX_HOOKER = 32};
	IFSMStateHooker *m_arrHookers[MAX_HOOKER];
	int m_iHookerCnt;
	void *m_strand; // make sure FSM event execute at one thread!!!
	LIST_ENTRY m_timerlist;
	LIST_ENTRY m_eventlist;
	LONG m_lInTrans;
};

template<class T>
class FSMImpl : public FSMBase
{
public:
	virtual void OnStateEntry(int state)
	{
		T *pT = static_cast<T*>(this);
#ifdef _WIN32
		T::FSMStateEntry* entry = pT->GetState(state);
#else
		auto entry = pT->GetState(state);
#endif //_WIN32
		if (entry->pOnEntry) {
			(pT->*(entry->pOnEntry))();
		}
	}

	virtual void OnStateExit(int state)
	{
		T *pT = static_cast<T*>(this);
#ifdef _WIN32
		T::FSMStateEntry* entry = pT->GetState(state);
#else
		auto entry = pT->GetState(state);
#endif //_WIN32
		if (entry->pOnExit) {
			(pT->*(entry->pOnExit))();
		}
	}

	virtual unsigned int OnStateEvent(FSMEvent *e)
	{
		T *pT = static_cast<T*>(this);
#ifdef _WIN32
		T::FSMStateEntry* entry = pT->GetCurrState();
#else
		auto entry = pT->GetCurrState();
#endif //_WIN32
		return (pT->*(entry->pOnEvent))(e);
	}

	virtual int MatchRule(int state, int evt, unsigned int rc)
	{
		T *pT = static_cast<T*>(this);
		int n = pT->GetRuleCount();
		for (int i = 0; i < n; ++i) {
			FSMRuleEntry *entry = pT->GetRule(i);
			if (state == entry->src_state) {
				if (evt == entry->evt) {
					if (rc >= entry->result_start && rc <= entry->result_end)
						return entry->dst_state;
				}
			}
		}
		return state; // no match
	}

	virtual BOOL FindStateEvent(int evt)
	{
		T *pT = static_cast<T*>(this);
		int n = pT->GetRuleCount();
		for (int i = 0; i < n; ++i) {
			FSMRuleEntry *entry = pT->GetRule(i);
			if (entry->src_state == m_iState && entry->evt == evt)
				return TRUE;
		}
		return FALSE;
	}

	const char *GetStateName(int iState) 
	{
		if (iState == FSM_STATE_INIT) {
			return "State_Start";
		} else if (iState == FSM_STATE_EXIT) {
			return "State_End";
		} else {
			T *pT = static_cast<T*>(this);
#ifdef _WIN32
			T::FSMStateEntry* entry = pT->GetState(iState);
#else
			auto entry = pT->GetState(iState);
#endif //_WIN32
			return entry ? entry->pszName : NULL;
		}
	}

	const char *GetCurrStateName()
	{
		return GetStateName(m_iState);
	}
};

#define BEGIN_FSM_STATE(cls) \
public: \
	typedef FSMStateEntryT<cls> FSMStateEntry; \
	typedef cls FSM; \
private: \
	FSMStateEntry *__EntryTable(int *iNum) {  \
		static FSMStateEntry tables[] = {

#define FSM_STATE_ENTRY(id, name, onentry, onexit, onevent) \
	{id, name, NULL, &FSM::onentry, &FSM::onexit, &FSM::onevent},

#define END_FSM_STATE() \
	}; \
	static int sorted = 0; \
	if (!sorted) { \
		int n = sizeof(tables)/sizeof(tables[0]); \
		for (int i = 0; i < n-1; ++i) { \
			FSMStateEntry *t = &tables[i]; \
			if (t->id != i) { \
				int j; \
				for (j = i+1; j < n; ++j) { \
					FSMStateEntry *tt = &tables[j]; \
					if (tt->id == i) \
						break; \
				} \
				assert(j < n); \
				FSMStateEntry tentry; \
				memcpy(&tentry, t, sizeof(FSMStateEntry)); \
				memcpy(t, &tables[j], sizeof(FSMStateEntry)); \
				memcpy(&tables[j], &tentry, sizeof(FSMStateEntry)); \
			} \
		} \
		sorted++; \
	} \
	if (iNum) \
		*iNum = sizeof(tables)/sizeof(tables[0]); \
	return &tables[0]; \
} \
public: \
FSMStateEntry *GetCurrState() \
{ \
	return GetState(m_iState); \
} \
FSMStateEntry *GetState(int iState) \
{ \
	int num; \
	FSMStateEntry *t = __EntryTable(&num); \
	assert(iState < num); \
	return t + iState; \
} \
int GetStateCount() \
{ \
	int num; \
	__EntryTable(&num); \
	return num; \
}

#define BEGIN_FSM_RULE(cls, init_state_id) \
public: \
virtual int GetInitState() { return init_state_id; } \
private: \
FSMRuleEntry *__RuleTable(int *iNum) { \
	static struct FSMRuleEntry table[] = {

#define FSM_RULE_ENTRY(src_state_id, dst_state_id, evt_id, action_result) \
	{src_state_id, dst_state_id, evt_id, action_result, action_result}, 

#define FSM_RULE_ENTRY_RANGE(src_state_id, dst_state_id, evt_id, action_result_start, action_result_end) \
	{src_state_id, dst_state_id, evt_id, action_result_start, action_result_end}, 

#define FSM_RULE_ENTRY_ANY(src_state_id, dst_state_id, evt_id)	\
	{src_state_id, dst_state_id, evt_id, 0,  (unsigned int)-1}, 

#define END_FSM_RULE() \
	};	\
	if (iNum) \
		*iNum = sizeof(table)/sizeof(table[0]); \
	return &table[0]; \
} \
public: \
FSMRuleEntry * GetRule(int iRule) \
{ \
	int num; \
	FSMRuleEntry *t = __RuleTable(&num); \
	assert(iRule < num); \
	return t + iRule; \
} \
int GetRuleCount() \
{ \
	int num; \
	__RuleTable(&num); \
	return num; \
}



#endif // __SPFSM_H