class BaseEvent native { } // just a base class. it doesn't inherit from Object on the scripting side so you can't call Destroy() on it and break everything.

class RenderEvent : BaseEvent native
{
    native readonly Vector3 ViewPos;
    native readonly double ViewAngle;
    native readonly double ViewPitch;
    native readonly double ViewRoll;
    native readonly double FracTic;
    native readonly Actor Camera;
}

class WorldEvent : BaseEvent native
{
    // for loaded/unloaded
    native readonly bool IsSaveGame;
    // for thingspawned/thingdied/thingdestroyed
    native readonly Actor Thing;
    // for thingdied. can be null
    native readonly Actor Inflictor;
    // for thingdamaged.
    native readonly int Damage;
    native readonly Actor DamageSource;
    native readonly Name DamageType;
    native readonly EDmgFlags DamageFlags;
    native readonly double DamageAngle;
}

class StaticEventHandler : Object native
{
    // static event handlers CAN register other static event handlers.
    // unlike EventHandler.Create that will not create them.
    protected static native StaticEventHandler Create(class<StaticEventHandler> type);
    protected static native StaticEventHandler CreateOnce(class<StaticEventHandler> type);
    protected static native StaticEventHandler Find(Class<StaticEventHandler> type); // just for convenience. who knows.
    
    protected static native bool Register(StaticEventHandler handler);
    protected static native bool Unregister(StaticEventHandler handler);

    // actual handlers are here
    virtual native void WorldLoaded(WorldEvent e);
    virtual native void WorldUnloaded(WorldEvent e);
    virtual native void WorldThingSpawned(WorldEvent e);
    virtual native void WorldThingDied(WorldEvent e);
    virtual native void WorldThingRevived(WorldEvent e);
    virtual native void WorldThingDamaged(WorldEvent e);
    virtual native void WorldThingDestroyed(WorldEvent e);
    virtual native void WorldLightning(WorldEvent e); // for the sake of completeness.
    virtual native void WorldTick(WorldEvent e);

    virtual native void RenderFrame(RenderEvent e);
    
    // this function should return a value that will be queried on Register() to decide the relative order of this handler to every other.
    // this is most useful in UI systems.
    // default is 0.
    virtual native int GetOrder();
}

class EventHandler : StaticEventHandler native
{
    static native StaticEventHandler Create(class<StaticEventHandler> type);
    static native StaticEventHandler CreateOnce(class<StaticEventHandler> type);
    static native StaticEventHandler Find(class<StaticEventHandler> type);

    static native bool Register(StaticEventHandler handler);
    static native bool Unregister(StaticEventHandler handler);
}