Add probabilistic branching helper

07_Basketball/csharp/Probably.cs

@@ -0,0 +1,32 @@
+using Games.Common.Randomness;
+
+namespace Basketball;
+
+internal struct Probably
+{
+    private readonly float _defenseFactor;
+    private readonly IRandom _random;
+    private readonly bool _done;
+
+    internal Probably(float defenseFactor, IRandom random, bool done = false)
+    {
+        _defenseFactor = defenseFactor;
+        _random = random;
+        _done = done;
+    }
+
+    public Probably Do(float probability, Action action)
+    {
+        if (!_done && _random.NextFloat() <= probability * _defenseFactor)
+        {
+            action.Invoke();
+            return new Probably(_defenseFactor, _random, true);
+        }
+
+        return this;
+    }
+
+    public Probably Or(float probability, Action action) => Do(probability, action);
+
+    public Probably Or(Action action) => Do(1f, action);
+}