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Game/Score/TotalScore.cs

@@ -0,0 +1,29 @@
+using System;
+using GodotHostTest.Interfaces;
+using R3;
+
+namespace GodotHostTest.Game.Score;
+
+public class TotalScore : IScore, IDisposable
+{
+    private readonly IDisposable _connectedObservableDisposable;
+
+    public TotalScore(ITargetEventBus targetEventBus)
+    {
+        var connectedObservable = targetEventBus.Hit.Select(_ => 20)
+            .Merge(targetEventBus.TimedOut.Select(_ => -5))
+            .Scan(0, (x1, x2) => x1 + x2)
+            .Prepend(0)
+            .Replay(1);
+        _connectedObservableDisposable = connectedObservable.Connect();
+        Score = connectedObservable.AsObservable();
+    }
+
+    public void Dispose()
+    {
+        _connectedObservableDisposable.Dispose();
+        GC.SuppressFinalize(this);
+    }
+
+    public Observable<int> Score { get; }
+}