/// <summary>
/// Checks an object for being a callback, and proxies it to move to the right thread if it is
/// </summary>
/// <param name="original">The original object that might be a callback</param>
/// <returns>The object that should now be the parameter, either just original, or a proxy for it if it was a callback</returns>
private object ConvertParameter(object original)
{
// See if this parameter is, or is in, an actor
IActor rootForObject = RootForObject(original);
if (rootForObject != null)
{
Delegate originalAsDelegate = original as Delegate;
if (originalAsDelegate != null)
{
// Special case for delegates: make a new delegate that calls the existing one in the right thread
Type returnType = originalAsDelegate.Method.ReturnType;
if (returnType != typeof(void))
{
// The method has a return type, fail fast
throw new InvalidOperationException("The delegate " + originalAsDelegate.GetType() +
" has a non-void return type. Actors may only be given callbacks with void return types.");
}
MethodCaller delegateMethodCaller = m_ProxyFactory.CreateDelegateCaller(originalAsDelegate.GetType(), originalAsDelegate.Method);
ActorMethodInvocationHandler methodInvocationHandler = new ActorMethodInvocationHandler(rootForObject, originalAsDelegate, delegateMethodCaller, m_ProxyFactory, returnType, originalAsDelegate.Method);
return(m_ProxyFactory.CreateDelegateProxy(methodInvocationHandler, originalAsDelegate.Method, original.GetType()));
}
else
{
// Yep, this object needs to be wrapped to move back to its actor's logical thread when it's used
ActorInterfaceInvocationHandler callbackInterceptor = new ActorInterfaceInvocationHandler(original, rootForObject, m_ProxyFactory);
// Find the object's interface which implements IActor (it might have others, but this is the important one)
Type interfaceType = null;
foreach (Type eachInterface in original.GetType().GetInterfaces())
{
if (typeof(IActor).IsAssignableFrom(eachInterface) && !eachInterface.Equals(typeof(IActor)))
{
interfaceType = eachInterface;
break;
}
}
if (interfaceType == null)
{
throw new ApplicationException("NAct encountered an internal inconsistency and will eat your cake.");
}
return(m_ProxyFactory.CreateInterfaceProxy(callbackInterceptor, interfaceType, true));
}
}
return(original);
}