/// <inheritdoc />
public IDisposable RegisterListener <TListener>(TListener listener, Func <Func <Task>, Task>?invoker = null)
where TListener : IEventListener
{
if (listener == null)
{
throw new ArgumentNullException(nameof(listener));
}
IReadOnlyList <RegisteredEventListener>?eventListeners = RegisteredEventListener.FromType(listener.GetType());
var disposes = new List <IDisposable>(eventListeners.Count);
foreach (var eventListener in eventListeners)
{
IRegisteredEventListener wrappedEventListener = new WrappedRegisteredEventListener(eventListener, listener);
if (invoker != null)
{
wrappedEventListener = new InvokedRegisteredEventListener(wrappedEventListener, invoker);
}
var register = _temporaryEventListeners.GetOrAdd(
wrappedEventListener.EventType,
_ => new TemporaryEventRegister());
disposes.Add(register.Add(wrappedEventListener));
}
if (eventListeners.Count > 0)
{
_cachedEventHandlers.TryRemove(typeof(TListener), out _);
}
return(new MultiDisposable(disposes));
}
/// <summary>
/// Get all the event listeners for the given event type.
/// </summary>
/// <returns>The event listeners.</returns>
private IEnumerable <EventHandler> GetHandlers <TEvent>()
where TEvent : IEvent
{
Type?eventType = typeof(TEvent);
var interfaces = eventType.GetInterfaces();
foreach (var @interface in interfaces)
{
if (_temporaryEventListeners.TryGetValue(@interface, out var cb))
{
foreach (var eventListener in cb.GetEventListeners())
{
yield return(new EventHandler(null, eventListener));
}
}
}
foreach (var handler in _serviceProvider.GetServices <IEventListener>())
{
if (handler is IManualEventListener manualEventListener && manualEventListener.CanExecute <TEvent>())
{
yield return(new EventHandler(handler, new ManualRegisteredEventListener(manualEventListener)));
continue;
}
var events = RegisteredEventListener.FromType(handler.GetType());
foreach (var eventHandler in events)
{
if (eventHandler.EventType != typeof(TEvent) && !interfaces.Contains(eventHandler.EventType))
{
continue;
}
yield return(new EventHandler(handler, eventHandler));
}
}
if (_temporaryEventListeners.TryGetValue(eventType, out var cb2))
{
foreach (var eventListener in cb2.GetEventListeners())
{
yield return(new EventHandler(null, eventListener));
}
}
}
