async extensions

Author: Dimonik333

Assets/CatCode/Commands/AsyncCommandExtensions.cs

@@ -0,0 +1,108 @@
+using System.Threading;
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace CatCode.Commands
+{
+    public static class AsyncCommandExtensions
+    {
+        public static Awaitable StartedToAwaitable(this ICommand command, CancellationToken token)
+        {
+            var tcs = new AwaitableCompletionSource();
+            if (command.State > CommandState.Idle)
+            {
+                tcs.SetResult();
+            }
+            else
+            {
+                var cts = token.Register(OnCancel);
+                command.Started += OnStarted;
+            }
+            return tcs.Awaitable;
+
+            void OnStarted()
+            {
+                command.Started -= OnStarted;
+                tcs.TrySetResult();
+            }
+
+            void OnCancel()
+            {
+                command.Started -= OnStarted;
+                tcs.TrySetCanceled();
+            }
+        }
+
+        public static Awaitable FinishToAwaitable(this ICommand command, CancellationToken token)
+        {
+            var tcs = new AwaitableCompletionSource();
+            if (command.State == CommandState.Finished)
+            {
+                tcs.SetResult();
+            }
+            else
+            {
+                var ctr = token.Register(OnCancel);
+                command.Finished += OnFinished;
+            }
+            return tcs.Awaitable;
+
+            void OnFinished()
+            {
+                command.Finished -= OnFinished;
+                tcs.TrySetResult();
+            }
+            void OnCancel()
+            {
+                command.Finished -= OnFinished;
+                tcs.TrySetCanceled();
+            }
+        }
+
+
+        public static Task StartToTask(this ICommand command, CancellationToken token)
+        {
+            if (command.State > CommandState.Idle)
+                return Task.CompletedTask;
+
+            var tcs = new TaskCompletionSource<bool>();
+            var ctr = token.Register(OnCancel);
+            command.Started += OnStarted;
+            return tcs.Task;
+
+            void OnStarted()
+            {
+                command.Started -= OnStarted;
+                tcs.TrySetResult(true);
+            }
+
+            void OnCancel()
+            {
+                command.Started -= OnStarted;
+                tcs.TrySetCanceled();
+            }
+        }
+
+        public static Task FinishToTask(this ICommand command, CancellationToken token)
+        {
+            if (command.State == CommandState.Finished)
+                return Task.CompletedTask;
+            
+            var tcs = new TaskCompletionSource<bool>();
+            var ctr = token.Register(OnCancel);
+            command.Finished += OnFinished;
+            return tcs.Task;
+
+            void OnFinished()
+            {
+                command.Finished -= OnFinished;
+                tcs.TrySetResult(true);
+            }
+            void OnCancel()
+            {
+                command.Finished -= OnFinished;
+                tcs.TrySetCanceled();
+            }
+        }
+    }
+}

Assets/CatCode/Commands/AsyncCommandExtensions.cs.meta

@@ -2,9 +2,9 @@
 {
     public enum CommandState
     {
-        Idle,
-        Executing,
-        Stopped,
-        Finished
+        Idle = 0,
+        Executing = 1,
+        Stopped = 2,
+        Finished = 3
     }
 }