//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: A global class that holds a prioritized queue of entity I/O events.
//			Events can be posted with a nonzero delay, which determines
//how long 			they are held before being dispatched to their recipients.
//
//			The queue is serviced once per server frame.
//
//=============================================================================//

#ifndef EVENTQUEUE_H
#define EVENTQUEUE_H
#ifdef _WIN32
#pragma once
#endif

#include "mempool.h"

struct EventQueuePrioritizedEvent_t {
    float m_flFireTime;
    string_t m_iTarget;
    string_t m_iTargetInput;
    EHANDLE m_pActivator;
    EHANDLE m_pCaller;
    int m_iOutputID;
    EHANDLE
        m_pEntTarget;  // a pointer to the entity to target; overrides m_iTarget

    variant_t m_VariantValue;  // variable-type parameter

    EventQueuePrioritizedEvent_t *m_pNext;
    EventQueuePrioritizedEvent_t *m_pPrev;

    DECLARE_SIMPLE_DATADESC();

    DECLARE_FIXEDSIZE_ALLOCATOR(PrioritizedEvent_t);
};

class CEventQueue {
   public:
    // pushes an event into the queue, targeting a string name (m_iName), or
    // directly by a pointer
    void AddEvent(const char *target, const char *action, variant_t Value,
                  float fireDelay, CBaseEntity *pActivator,
                  CBaseEntity *pCaller, int outputID = 0);
    void AddEvent(CBaseEntity *target, const char *action, float fireDelay,
                  CBaseEntity *pActivator, CBaseEntity *pCaller,
                  int outputID = 0);
    void AddEvent(CBaseEntity *target, const char *action, variant_t Value,
                  float fireDelay, CBaseEntity *pActivator,
                  CBaseEntity *pCaller, int outputID = 0);

    void CancelEvents(CBaseEntity *pCaller);
    void CancelEventOn(CBaseEntity *pTarget, const char *sInputName);
    bool HasEventPending(CBaseEntity *pTarget, const char *sInputName);

    // services the queue, firing off any events who's time hath come
    void ServiceEvents(void);

    // debugging
    void ValidateQueue(void);

    // serialization
    int Save(ISave &save);
    int Restore(IRestore &restore);

    CEventQueue();
    ~CEventQueue();

    void Init(void);
    void Clear(void);  // resets the list

    void Dump(void);

   private:
    void AddEvent(EventQueuePrioritizedEvent_t *event);
    void RemoveEvent(EventQueuePrioritizedEvent_t *pe);

    DECLARE_SIMPLE_DATADESC();
    EventQueuePrioritizedEvent_t m_Events;
    int m_iListCount;
};

extern CEventQueue g_EventQueue;

#endif  // EVENTQUEUE_H