public async Task HandleEventAsync(IExportEvent exportEvent, CancellationToken token)
{
if (exportEvent == null)
{
throw new ArgumentNullException(nameof(exportEvent));
}
var handlerType = GetHandlerType(exportEvent);
if (handlerType == null)
{
return;
}
var handlers = (IEnumerable <object>)_services.GetService(handlerType);
if (!handlers.Any())
{
return;
}
var method = GetHandlerMethod(exportEvent);
await method(handlers, exportEvent, token);
}
private void Handle(IExportEvent <UpdateObjectPayload> exportEvent, CancellationToken token)
{
if (exportEvent.Event != EventType.UpdateObject)
{
return;
}
var id = exportEvent.Payload.Id;
var position = exportEvent.Payload.Position;
var isUpdated = false;
do
{
if (!_state.Objects.TryGetValue(id, out var obj))
{
return;
}
var updated = obj with
{
Position = position
};
isUpdated = _state.Objects.TryUpdate(id, updated, obj);
} while (!isUpdated);
}
}
private static GenericHandlerDelegate GetHandlerMethod(IExportEvent exportEvent)
{
return(HandlerMethodMap.GetOrAdd(exportEvent.GetType(), type =>
{
var payloadType = GetPayloadType(type);
if (payloadType == null)
{
return null;
}
var handlersType = typeof(IEnumerable <>).MakeGenericType(
typeof(IExportEventHandler <>).MakeGenericType(payloadType)
);
var eventType = typeof(IExportEvent <>).MakeGenericType(payloadType);
var method = HandleGenericEventMethod.MakeGenericMethod(payloadType);
var handlersParam = Expression.Parameter(typeof(object), "handlers");
var eventParam = Expression.Parameter(typeof(IExportEvent), "exportEvent");
var tokenParam = Expression.Parameter(typeof(CancellationToken), "token");
var castHandlers = Expression.Convert(handlersParam, handlersType);
var castEvent = Expression.Convert(eventParam, eventType);
var callExpression = Expression.Call(method, castHandlers, castEvent, tokenParam);
var lambda = Expression.Lambda <GenericHandlerDelegate>(callExpression, handlersParam, eventParam, tokenParam);
return lambda.Compile();
}));
}
private void Handle(IExportEvent <AddObjectPayload> exportEvent, CancellationToken token)
{
if (exportEvent.Event != EventType.AddObject)
{
return;
}
_state.Objects.TryAdd(exportEvent.Payload.Id, exportEvent.Payload);
}
Task IExportEventHandler.HandleEventAsync(IExportEvent exportEvent, CancellationToken token)
{
lock (_syncRoot)
{
_events.Add(exportEvent);
}
return(Task.CompletedTask);
}
private void Handle(IExportEvent <RemoveObjectPayload> exportEvent, CancellationToken token)
{
if (exportEvent.Event != EventType.RemoveObject)
{
return;
}
_state.Objects.TryRemove(exportEvent.Payload.Id, out _);
}
public Task HandleEventAsync(IExportEvent <InitPayload> exportEvent, CancellationToken token)
{
_state.IsRunning = true;
_state.MissionName = exportEvent.Payload.MissionName;
_state.Theatre = exportEvent.Payload.Theatre;
_state.MapCenter = exportEvent.Payload.MapCenter;
return(Task.CompletedTask);
}
public Task HandleEventAsync(IExportEvent <MissionEndPayload> exportEvent, CancellationToken token)
{
_state.IsRunning = false;
_state.Objects.Clear();
_state.Airbases.Clear();
_state.MissionName = null;
_state.Theatre = null;
_state.MapCenter = null;
_state.Time = default;
return(Task.CompletedTask);
}
private static Type GetHandlerType(IExportEvent exportEvent)
{
return(EventHandlerTypeMap.GetOrAdd(exportEvent.GetType(), type =>
{
var payloadType = GetPayloadType(type);
if (payloadType == null)
{
return null;
}
var handlerType = typeof(IExportEventHandler <>).MakeGenericType(payloadType);
var enumerableType = typeof(IEnumerable <>).MakeGenericType(handlerType);
return enumerableType;
}));
}
private void Handle(IExportEvent <TimePayload> exportEvent, CancellationToken token)
{
_state.Time = exportEvent.Payload.Time;
}
public Task HandleEventAsync(IExportEvent <TimePayload> exportEvent, CancellationToken token)
{
Handle(exportEvent, token);
return(Task.CompletedTask);
}
private static async Task HandleGenericEventAsync <T>(IEnumerable <IExportEventHandler <T> > handlers, IExportEvent <T> exportEvent, CancellationToken token)
{
foreach (var handler in handlers)
{
await handler.HandleEventAsync(exportEvent, token);
}
}
private void Handle(IExportEvent <AddAirbasePayload> exportEvent)
{
_liveState.Airbases[exportEvent.Payload.Id] = exportEvent.Payload;
}
