Operations pipeline start

WotBlitzStatisticsPro.Logic/Pipeline/OperationMediator.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Threading.Tasks;
+
+namespace WotBlitzStatisticsPro.Logic.Pipeline
+{
+    public class OperationMediator<TContext>: IOperation<TContext>
+    {
+        private readonly IOperation<TContext> _current;
+        private readonly IOperation<TContext> _next;
+
+        public OperationMediator(IOperation<TContext> current, IOperation<TContext> next)
+        {
+            _current = current ?? throw new ArgumentNullException(nameof(current));
+            _next = next;
+        }
+
+        public Task Invoke(TContext context, Func<TContext, Task> next)
+        {
+            return _current.Invoke(context, c => _next == null ? Task.CompletedTask : _next.Invoke(c, null));
+        }
+    }
+}