Files
Unity20GameJam/Assets/A2WToolBox/3rd/EventBetter/EventBetter.cs

656 lines
20 KiB
C#

// EventBetter
// Copyright (c) 2018, Piotr Gwiazdowski <gwiazdorrr+github at gmail.com>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.LowLevel;
using UnityEngine.PlayerLoop;
/// <summary>
/// Intentionally made partial, in case you want to extend it easily.
/// </summary>
public static partial class EventBetter
{
/// <summary>
/// Register a message handler.
///
/// The <paramref name="handler"/> will be invoked every time a message of type <typeparamref name="MessageType"/> is raised,
/// unless <paramref name="listener"/> gets destroyed or one of Unlisten/Clear methods is called.
/// </summary>
/// <typeparam name="ListenerType"></typeparam>
/// <typeparam name="MessageType"></typeparam>
/// <param name="listener"></param>
/// <param name="handler"></param>
/// <param name="once">After the <paramref name="handler"/> is invoked - unlisten automatically.</param>
/// <param name="excludeInactive">If <paramref name="listener"/> is a Behaviour or GameObject, will only invoke <paramref name="handler"/>
/// if <paramref name="listener"/> is active and enabled.</param>
/// <exception cref="System.InvalidOperationException">Thrown if the internal worker has been disabled somehow.</exception>
public static void Listen<ListenerType, MessageType>(ListenerType listener, System.Action<MessageType> handler,
bool once = false,
bool excludeInactive = false,
bool persistent = false)
where ListenerType : UnityEngine.Object
{
HandlerFlags flags = HandlerFlags.IsUnityObject;
if (once)
flags |= HandlerFlags.Once;
if (excludeInactive)
flags |= HandlerFlags.OnlyIfActiveAndEnabled;
if (persistent)
flags |= HandlerFlags.Persistent;
RegisterInternal(listener, handler, flags);
}
/// <summary>
/// Register a message handler. No listener, you unregister by calling <see cref="IDisposable.Dispose">Dispose</see> on returned object.
/// Handler is not limited in what it is allowed to capture.
/// </summary>
/// <typeparam name="MessageType"></typeparam>
/// <param name="handler"></param>
/// <returns></returns>
public static IDisposable ListenManual<MessageType>(System.Action<MessageType> handler)
{
// use the dict as a listener here, it will ensure the handler is going to live forever
var actualHandler = RegisterInternal<object, MessageType>(s_entries, (msg) => handler(msg), HandlerFlags.None);
return new ManualHandlerDisposable()
{
Handler = actualHandler,
MessageType = typeof(MessageType)
};
}
/// <summary>
/// Invoke all registered handlers for this message type immediately.
/// </summary>
/// <typeparam name="MessageType"></typeparam>
/// <param name="message"></param>
/// <returns>True if there are any handlers for this message type, false otherwise.</returns>
public static bool Raise<MessageType>(MessageType message)
{
return RaiseInternal(message);
}
/// <summary>
/// Unregisters all <typeparamref name="MessageType"/> handlers for a given listener.
/// </summary>
/// <typeparam name="MessageType"></typeparam>
/// <param name="listener"></param>
/// <returns>True if there were any handlers, false otherwise.</returns>
public static bool Unlisten<MessageType>(UnityEngine.Object listener)
{
if (listener == null)
throw new ArgumentNullException("listener");
return UnregisterInternal(typeof(MessageType), listener, (eventEntry, index, referenceListener) => object.ReferenceEquals(eventEntry.listeners[index], referenceListener));
}
/// <summary>
/// Unregisters all message types for a given listener.
/// </summary>
/// <param name="listener"></param>
/// <returns>True if there were any handlers, false otherwise.</returns>
public static bool UnlistenAll(UnityEngine.Object listener)
{
if (listener == null)
throw new ArgumentNullException("listener");
bool anyListeners = false;
foreach (var entry in s_entriesList)
{
anyListeners |= UnregisterInternal(entry, listener, (eventEntry, index, referenceListener) => object.ReferenceEquals(eventEntry.listeners[index], referenceListener));
}
return anyListeners;
}
/// <summary>
/// Unregisters everything.
/// </summary>
public static void Clear(bool clearPersistent = true)
{
if (clearPersistent)
{
s_entries.Clear();
s_entriesList.Clear();
}
else
{
foreach (var entry in s_entriesList)
{
RemoveNonPersistentHandlers(entry);
}
}
}
/// <summary>
/// Removes handlers that will now longer be called because their listeners have been destroyed. Normally
/// there's no reason to call that, since EventBetter does it behind the scenes in every LateUpdate.
/// </summary>
public static void RemoveUnusedHandlers()
{
foreach (var entry in s_entriesList)
{
RemoveUnusedHandlers(entry);
}
}
#region Coroutine Support
/// <summary>
/// Use this in coroutines. Yield will return when at least one event of type <typeparamref name="MessageType"/>
/// has been raised. To get the messages use <see cref="YieldListener{MessageType}.First"/> or
/// <see cref="YieldListener{MessageType}.Messages"/>
/// </summary>
/// <typeparam name="MessageType"></typeparam>
/// <returns></returns>
public static YieldListener<MessageType> ListenWait<MessageType>()
where MessageType : class
{
return new YieldListener<MessageType>();
}
public class YieldListener<MessageType> : System.Collections.IEnumerator, IDisposable
where MessageType : class
{
private Delegate handler;
public List<MessageType> Messages { get; private set; }
public MessageType First
{
get
{
if (Messages == null || Messages.Count == 0)
return null;
return Messages[0];
}
}
internal YieldListener()
{
handler = EventBetter.RegisterInternal<YieldListener<MessageType>, MessageType>(
this, (msg) => OnMessage(msg), HandlerFlags.DontInvokeIfAddedInAHandler);
}
public void Dispose()
{
if (handler != null)
{
EventBetter.UnlistenHandler(typeof(MessageType), handler);
handler = null;
}
}
private void OnMessage(MessageType msg)
{
if (Messages == null)
{
Messages = new List<MessageType>();
}
Messages.Add(msg);
}
bool System.Collections.IEnumerator.MoveNext()
{
if (Messages != null)
{
Dispose();
return false;
}
return true;
}
object System.Collections.IEnumerator.Current
{
get { return null; }
}
void System.Collections.IEnumerator.Reset()
{
}
}
#endregion
#region Async Support
public static async Task<MessageType> ListenAsync<MessageType>()
{
var tcs = new TaskCompletionSource<MessageType>();
var handler = RegisterInternal<object, MessageType>(s_entries,
(msg) => tcs.SetResult(msg), HandlerFlags.DontInvokeIfAddedInAHandler);
try
{
return await tcs.Task;
}
finally
{
EventBetter.UnlistenHandler(typeof(MessageType), handler);
}
}
#endregion
#region Private
private class ManualHandlerDisposable : IDisposable
{
public Type MessageType { get; set; }
public Delegate Handler { get; set; }
public void Dispose()
{
if (Handler == null)
return;
try
{
UnlistenHandler(MessageType, Handler);
}
finally
{
MessageType = null;
Handler = null;
}
}
}
[Flags]
private enum HandlerFlags
{
None = 0,
OnlyIfActiveAndEnabled = 1 << 0,
Once = 1 << 1,
DontInvokeIfAddedInAHandler = 1 << 2,
IsUnityObject = 1 << 3,
Persistent = 1 << 4,
}
private class EventEntry
{
public uint invocationCount = 0;
public bool needsCleanup = false;
public readonly List<object> listeners = new List<object>();
public readonly List<Delegate> handlers = new List<Delegate>();
public readonly List<HandlerFlags> flags = new List<HandlerFlags>();
public int Count
{
get { return listeners.Count; }
}
public bool HasFlag(int i, HandlerFlags flag)
{
return (flags[i] & flag) == flag;
}
public void SetFlag(int i, HandlerFlags flag, bool value)
{
if (value)
{
flags[i] |= flag;
}
else
{
flags[i] &= ~flag;
}
}
public void Add(object listener, Delegate handler, HandlerFlags flag)
{
UnityEngine.Debug.Assert(listeners.Count == handlers.Count);
// if not in a handler, don't set this flag as it would ignore first
// nested handler
if (invocationCount == 0)
flag &= ~HandlerFlags.DontInvokeIfAddedInAHandler;
listeners.Add(listener);
handlers.Add(handler);
flags.Add(flag);
}
public void NullifyAt(int i)
{
UnityEngine.Debug.Assert(listeners.Count == handlers.Count);
listeners[i] = null;
handlers[i] = null;
flags[i] = HandlerFlags.None;
}
public void RemoveAt(int i)
{
UnityEngine.Debug.Assert(listeners.Count == handlers.Count);
listeners.RemoveAt(i);
handlers.RemoveAt(i);
flags.RemoveAt(i);
}
}
/// <summary>
/// For lookups.
/// </summary>
private static Dictionary<Type, EventEntry> s_entries = new Dictionary<Type, EventEntry>();
/// <summary>
/// For faster iteration.
/// </summary>
private static List<EventEntry> s_entriesList = new List<EventEntry>();
private static bool RaiseInternal<T>(T message)
{
EventEntry entry;
if (!s_entries.TryGetValue(typeof(T), out entry))
return false;
bool hadActiveHandlers = false;
var invocationCount = ++entry.invocationCount;
try
{
int initialCount = entry.Count;
for (int i = 0; i < entry.Count; ++i)
{
var listener = GetAliveTarget(entry.listeners[i]);
bool removeHandler = true;
if (listener != null)
{
if (entry.HasFlag(i, HandlerFlags.OnlyIfActiveAndEnabled))
{
var behaviour = listener as UnityEngine.Behaviour;
if (!ReferenceEquals(behaviour, null))
{
if (!behaviour.isActiveAndEnabled)
continue;
}
var go = listener as GameObject;
if (!ReferenceEquals(go, null))
{
if (!go.activeInHierarchy)
continue;
}
}
if (i >= initialCount)
{
// this is a new handler; if it has a protection flag, don't call it
if (entry.HasFlag(i, HandlerFlags.DontInvokeIfAddedInAHandler))
{
entry.SetFlag(i, HandlerFlags.DontInvokeIfAddedInAHandler, false);
continue;
}
}
if (!entry.HasFlag(i, HandlerFlags.Once))
{
removeHandler = false;
}
((Action<T>)entry.handlers[i])(message);
hadActiveHandlers = true;
}
if (removeHandler)
{
if (invocationCount == 1)
{
// it's OK to compact now
entry.RemoveAt(i);
--i;
--initialCount;
}
else
{
// need to wait
entry.needsCleanup = true;
entry.NullifyAt(i);
}
}
}
}
finally
{
UnityEngine.Debug.Assert(invocationCount == entry.invocationCount);
--entry.invocationCount;
if (invocationCount == 1 && entry.needsCleanup)
{
entry.needsCleanup = false;
RemoveUnusedHandlers(entry);
}
}
return hadActiveHandlers;
}
private static Delegate RegisterInternal<ListenerType, MessageType>(ListenerType listener, System.Action<MessageType> handler, HandlerFlags flags)
{
return RegisterInternal<MessageType>(listener, handler, flags);
}
private static Delegate RegisterInternal<T>(object listener, Action<T> handler, HandlerFlags flags)
{
if (listener == null)
throw new ArgumentNullException("listener");
if (handler == null)
throw new ArgumentNullException("handler");
if ((flags & HandlerFlags.IsUnityObject) == HandlerFlags.IsUnityObject)
{
Debug.Assert(listener is UnityEngine.Object);
}
EventEntry entry;
if (!s_entries.TryGetValue(typeof(T), out entry))
{
entry = new EventEntry();
s_entries.Add(typeof(T), entry);
s_entriesList.Add(entry);
}
entry.Add(listener, handler, flags);
return handler;
}
private static bool UnlistenHandler(Type messageType, Delegate handler)
{
return EventBetter.UnregisterInternal(messageType, handler, (eventEntry, index, _handler) => eventEntry.handlers[index] == _handler);
}
private static bool UnregisterInternal<ParamType>(Type messageType, ParamType param, Func<EventEntry, int, ParamType, bool> predicate)
{
EventEntry entry;
if (!s_entries.TryGetValue(messageType, out entry))
{
return false;
}
return UnregisterInternal(entry, param, predicate);
}
private static bool UnregisterInternal<ParamType>(EventEntry entry, ParamType param, Func<EventEntry, int, ParamType, bool> predicate)
{
bool found = false;
for (int i = 0; i < entry.Count; ++i)
{
if (entry.listeners[i] == null)
continue;
if (predicate != null && !predicate(entry, i, param))
continue;
found = true;
if (entry.invocationCount == 0)
{
// it's ok to compact now
entry.RemoveAt(i);
--i;
}
else
{
// need to wait
entry.needsCleanup = true;
entry.NullifyAt(i);
}
}
return found;
}
private static object GetAliveTarget(object target)
{
if (target == null)
return null;
var targetAsUnityObject = target as UnityEngine.Object;
if (object.ReferenceEquals(targetAsUnityObject, null))
return target;
if (targetAsUnityObject)
return target;
return null;
}
private static void RemoveUnusedHandlers(EventEntry entry)
{
for (int i = 0; i < entry.Count; ++i)
{
var listener = entry.listeners[i];
if (entry.HasFlag(i, HandlerFlags.IsUnityObject))
{
if ((UnityEngine.Object)listener != null)
continue;
}
else
{
if (listener != null)
continue;
}
if (entry.invocationCount == 0)
entry.RemoveAt(i--);
else
entry.NullifyAt(i);
}
}
private static void RemoveNonPersistentHandlers(EventEntry entry)
{
for (int i = 0; i < entry.Count; ++i)
{
if (entry.HasFlag(i, HandlerFlags.Persistent))
{
continue;
}
Debug.Assert(entry.invocationCount == 0);
entry.RemoveAt(i--);
}
}
#endregion
#region Player Loop System Registration
struct EventBetterCleanupSystem
{
}
static EventBetter()
{
#if UNITY_EDITOR
UnityEditor.EditorApplication.playModeStateChanged += (change) =>
{
if (change == UnityEditor.PlayModeStateChange.ExitingPlayMode || change == UnityEditor.PlayModeStateChange.ExitingEditMode)
{
Clear(clearPersistent: false);
}
};
#endif
var rootPlayerLoopSystem = PlayerLoop.GetCurrentPlayerLoop();
var playerLoopSystemTypes = GetPlayerLoopSystemHierarchy(typeof(PreLateUpdate.ScriptRunBehaviourLateUpdate));
RegisterPlayerLoopSystem(ref rootPlayerLoopSystem, playerLoopSystemTypes);
PlayerLoop.SetPlayerLoop(rootPlayerLoopSystem);
Type[] GetPlayerLoopSystemHierarchy(Type systemType)
{
List<Type> result = new();
for (var t = systemType; t != null; t = t.DeclaringType)
{
result.Insert(0, t);
}
return result.ToArray();
}
void RegisterPlayerLoopSystem(ref PlayerLoopSystem parentSystem, Span<Type> subSystemTypes)
{
Debug.Assert(subSystemTypes.Length >= 1);
ref PlayerLoopSystem[] list = ref parentSystem.subSystemList;
if (list != null)
{
for (int i = 0; i < list.Length; ++i)
{
if (list[i].type != subSystemTypes[0])
{
continue;
}
if (subSystemTypes.Length == 1)
{
// insert after
var newSystem = new PlayerLoopSystem()
{
type = typeof(EventBetterCleanupSystem),
updateDelegate = EventBetter.RemoveUnusedHandlers
};
List<PlayerLoopSystem> tmpList = list.ToList();
tmpList.Insert(i+1, newSystem);
list = tmpList.ToArray();
}
else
{
RegisterPlayerLoopSystem(ref list[i], subSystemTypes.Slice(1));
}
return;
}
}
throw new InvalidOperationException($"SubSystem {subSystemTypes[0]} is not found in {parentSystem.type}");
}
}
#endregion
}