Refactor payouts processing (#6314)

BTCPayServer/ResourceTracker.cs

@@ -0,0 +1,38 @@
+#nullable enable
+using System;
+using System.Collections.Concurrent;
+
+namespace BTCPayServer
+{
+    public class ResourceTracker<T> where T: notnull
+    {
+        public class ScopedResourceTracker : IDisposable
+        {
+            private ResourceTracker<T> _parent;
+
+            public ScopedResourceTracker(ResourceTracker<T> resourceTracker)
+            {
+                _parent = resourceTracker;
+            }
+            ConcurrentDictionary<T, string> _Scoped = new();
+            public bool TryTrack(T resource)
+            {
+                if (!_parent._TrackedResources.TryAdd(resource, string.Empty))
+                    return false;
+                _Scoped.TryAdd(resource, string.Empty);
+                return true;
+            }
+
+            public bool Contains(T resource) => _Scoped.ContainsKey(resource);
+
+            public void Dispose()
+            {
+                foreach (var d in _Scoped)
+                    _parent._TrackedResources.TryRemove(d.Key, out _);
+            }
+        }
+        internal ConcurrentDictionary<T, string> _TrackedResources = new();
+        public ScopedResourceTracker StartTracking() => new ScopedResourceTracker(this);
+        public bool Contains(T resource) => _TrackedResources.ContainsKey(resource);
+    }
+}