public GetIdentityAndDrawObject(DeathWatch deathWatch, SharePack sharePack, Func <Stream, T> stripFile)
{
mDeathWatch = deathWatch;
SharePack = sharePack;
mStripFile = stripFile;
}
public static OfResourceBank.DResourceSourceDefinition <T> GetFileResource <T>(string originalPath, Func <Stream, T> stripFile, DWithFileWatcherToDispose withFileWatcherToDispose)
{
// weakref - don't hard link the recipient - he goes we don't have it
// should only ever get 1 element
var listenersForChange = new List <WeakReference <Action <Func <OfResourceBank.IdentityAndDraw <T> > > > >();
var sharePack = new SharePack(originalPath);
//var getIdentityAndDrawObject = new GetIdentityAndDrawObject<T>(new DeathWatch(watcher.Dispose), originalPath, stripFile);
var theLock = sharePack.mTheLock;
WeakReference <GetIdentityAndDrawObject <T> > weakGetIdentity = null;
Action <Option <string> > thereWasAChangeToSetPath =
possibleSuccessorPath =>
{
WeakReference <Action <Func <OfResourceBank.IdentityAndDraw <T> > > >[] relevantListenersForChange = null;
lock (theLock)
{
possibleSuccessorPath.ForEach(successorPath => sharePack.MutablePath = successorPath);
sharePack.MutableIdentity = Guid.NewGuid().ToString();
relevantListenersForChange = listenersForChange.ToArray();
//getIdentityAndDrawObject.UnderReplacement = true;
}
// Never, ever call back in lock we are the downsteram lock
foreach (var listener in relevantListenersForChange)
{
Action <Func <OfResourceBank.IdentityAndDraw <T> > > func = null;
if (listener.TryGetTarget(out func))
{
GetIdentityAndDrawObject <T> getIdentity = null;
if (weakGetIdentity.TryGetTarget(out getIdentity))
{
func(getIdentity.GetIdentityAndDraw);
}
}
}
lock (theLock)
{
// getIdentityAndDrawObject.UnderReplacement = false;
System.Threading.Monitor.PulseAll(theLock); // wake up any waiting get operation
}
// don't capture watcher indirectly in here, or it'll be a circular and never dispose.
};
return
(With(
withFileWatcherToDispose(
thereWasAChangeToSetPath,
originalPath),
watcherDispose =>
{
var getIdentityAndDrawObject = new GetIdentityAndDrawObject <T>(new DeathWatch(watcherDispose), sharePack, stripFile);
weakGetIdentity = new WeakReference <GetIdentityAndDrawObject <T> >(getIdentityAndDrawObject);
return new OfResourceBank.DResourceSourceDefinition <T>(
sinkReplacementOnChange => // the guy accepting the sink.
{
lock (theLock)
{
listenersForChange.Add(new WeakReference <Action <Func <OfResourceBank.IdentityAndDraw <T> > > >(sinkReplacementOnChange));
return getIdentityAndDrawObject.GetIdentityAndDraw; // deliberately capturing the deathwatch in its contents - anyone keeping the ability to read keeps the watcher alive
}
});
}));
}