timers.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * Additional copyright for this file:
 * Copyright (C) 1995-1997 Presto Studios, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef PEGASUS_TIMERS_H
#define PEGASUS_TIMERS_H

#include "common/rational.h"
#include "common/func.h"

#include "pegasus/constants.h"
#include "pegasus/notification.h"
#include "pegasus/util.h"

namespace Pegasus {

class Idler {
friend class PegasusEngine;

public:
    Idler();
    virtual ~Idler();

    virtual void startIdling();
    virtual void stopIdling();
    bool isIdling() const { return _isIdling; }

protected:
    virtual void useIdleTime() {}

    bool _isIdling;
    Idler *_nextIdler, *_prevIdler;
};

enum {
    kLoopTimeBase           = 1,
    kPalindromeLoopTimeBase = 2,
    kMaintainTimeBaseZero   = 4
};

class TimeBaseCallBack;

class TimeBase {
friend class TimeBaseCallBack;
public:
    TimeBase(const TimeScale = kDefaultTimeScale);
    virtual ~TimeBase();

    virtual void setTime(const TimeValue, const TimeScale = 0);
    virtual TimeValue getTime(const TimeScale = 0);

    virtual void setScale(const TimeScale scale) { _preferredScale = scale; }
    virtual TimeScale getScale() const { return _preferredScale; }

    virtual void setRate(const Common::Rational);
    virtual Common::Rational getRate() const { return _rate; }

    virtual void start();
    virtual void stop();
    virtual bool isRunning();

    virtual void pause();
    virtual void resume();
    bool isPaused() const { return _paused; }

    virtual void setFlags(const uint32 flags) { _flags = flags; }
    virtual uint32 getFlags() const { return _flags; }

    virtual void setStart(const TimeValue, const TimeScale = 0);
    virtual TimeValue getStart(const TimeScale = 0) const;

    virtual void setStop(const TimeValue, const TimeScale = 0);
    virtual TimeValue getStop(const TimeScale = 0) const;

    virtual void setSegment(const TimeValue, const TimeValue, const TimeScale = 0);
    virtual void getSegment(TimeValue&, TimeValue&, const TimeScale = 0) const;

    virtual TimeValue getDuration(const TimeScale = 0) const;

    virtual void setMasterTimeBase(TimeBase *timeBase);

    void disposeAllCallBacks();

    // ScummVM's API additions (to replace the need for actual timers)
    virtual void checkCallBacks();

protected:
    void addCallBack(TimeBaseCallBack *);
    void removeCallBack(TimeBaseCallBack *);
    virtual void updateTime();

    TimeBase *_master;
    TimeScale _preferredScale;
    TimeBaseCallBack *_callBackList;
    Common::Rational _rate, _pausedRate;
    bool _paused;
    uint32 _startTime, _startScale;
    uint32 _stopTime, _stopScale;
    uint32 _flags;

    Common::Rational _time;
    uint32 _lastMillis, _pauseStart;
};

// Type passed to initCallBack()
enum CallBackType {
    kCallBackNone = 0,
    kCallBackAtTime = 1,
    kCallBackAtExtremes = 4
};

// Trigger passed to scheduleCallBack()
enum CallBackTrigger {
    kTriggerNone = 0,

    // AtTime flags
    kTriggerTimeFwd = 1,

    // AtExtremes flags
    kTriggerAtStart = 1,
    kTriggerAtStop = 2
};

class TimeBaseCallBack {
friend class TimeBase;

public:
    TimeBaseCallBack();
    virtual ~TimeBaseCallBack();

    void initCallBack(TimeBase *, CallBackType type);

    void releaseCallBack();

    void scheduleCallBack(CallBackTrigger trigger, uint32 param2, uint32 param3);
    void cancelCallBack();

protected:
    virtual void callBack() = 0;

    TimeBase *_timeBase;

    // Owned and operated by TimeBase;
    TimeBaseCallBack *_nextCallBack;

    // Our storage of the QuickTime timer crap
    CallBackType _type;
    CallBackTrigger _trigger;
    uint32 _param2, _param3;
    bool _hasBeenTriggered;

private:
    void disposeCallBack();
};

class IdlerTimeBase : public Idler, public TimeBase {
public:
    IdlerTimeBase();
    ~IdlerTimeBase() override { stopIdling(); }

    TimeValue getLastTime() const { return _lastTime; }

protected:
    void useIdleTime() override;
    virtual void timeChanged(const TimeValue) {}

    TimeValue _lastTime;

};

class NotificationCallBack : public TimeBaseCallBack {
public:
    NotificationCallBack();
    ~NotificationCallBack() override {}

    void setNotification(Notification *notifier) { _notifier = notifier; }

    void setCallBackFlag(const NotificationFlags flag) { _callBackFlag = flag; }
    NotificationFlags getCallBackFlag() const { return _callBackFlag; }

protected:
    void callBack() override;

    Notification *_notifier;
    NotificationFlags _callBackFlag;
};

class DynamicElement : public TimeBase {
public:
    TimeValue percentSeconds(const uint32 percent) { return getScale() * percent / 100; }
};

class Fuse : private NotificationReceiver {
public:
    Fuse();
    ~Fuse() override {}

    void primeFuse(const TimeValue, const TimeScale = 1); // An appropriately named function :P
    void lightFuse();
    void stopFuse();
    bool isFuseLit() { return _fuseTimer.isRunning() || _fuseTimer.isPaused(); }
    void advanceFuse(const TimeValue);
    TimeValue getTimeRemaining();
    TimeScale getFuseScale() { return _fuseTimer.getScale(); }

    void pauseFuse() { _fuseTimer.pause(); }
    void resumeFuse() { _fuseTimer.resume(); }
    bool isFusePaused() { return _fuseTimer.isPaused(); }

protected:
    void receiveNotification(Notification *, const NotificationFlags) override;
    virtual void invokeAction() {}

    TimeBase _fuseTimer;
    NotificationCallBack _fuseCallBack;
    Notification _fuseNotification;
};

class FuseFunction : public Fuse {
public:
    FuseFunction() : _functor(0) {}
    ~FuseFunction() override { delete _functor; }

    void setFunctor(Common::Functor0<void> *functor) { delete _functor; _functor = functor; }
protected:
    void invokeAction() override { if (_functor && _functor->isValid()) (*_functor)(); }

    Common::Functor0<void> *_functor;
};

} // End of namespace Pegasus

#endif