From cd30047e4aacbd022eef660786b6eb508251ba7a Mon Sep 17 00:00:00 2001
From: Syntriax <Syntriax@gmail.com>
Date: Wed, 28 May 2025 16:55:38 +0300
Subject: [PATCH] feat: GetOrAddBehaviour with fallback type added

---
 .../Extensions/BehaviourControllerExtensions.cs     | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/Engine.Core/Extensions/BehaviourControllerExtensions.cs b/Engine.Core/Extensions/BehaviourControllerExtensions.cs
index 6778065..3f71685 100644
--- a/Engine.Core/Extensions/BehaviourControllerExtensions.cs
+++ b/Engine.Core/Extensions/BehaviourControllerExtensions.cs
@@ -39,6 +39,19 @@ public static class BehaviourControllerExtensions
     public static T GetOrAddBehaviour<T>(this IBehaviourController behaviourController, params object?[]? args) where T : class, IBehaviour
         => behaviourController.GetBehaviour<T>() ?? behaviourController.AddBehaviour<T>(args);
 
+    /// <summary>
+    /// Gets an existing <see cref="IBehaviour"/> of the specified type, or adds and returns the fallback type if it doesn't exist.
+    /// </summary>
+    /// <typeparam name="TOriginal">The type of <see cref="IBehaviour"/> to get.</typeparam>
+    /// <typeparam name="TFallback">The type of <see cref="IBehaviour"/> to add. It must be assignable from <typeparamref name="TOriginal"/></typeparam>
+    /// <param name="behaviourController">The <see cref="IBehaviourController"/> to search in.</param>
+    /// <param name="args">Optional arguments to pass to the constructor of the <see cref="IBehaviour"/> if a new one is added.</param>
+    /// <returns>The existing or newly added <see cref="IBehaviour"/> of the specified type.</returns>
+    public static TOriginal GetOrAddBehaviour<TOriginal, TFallback>(this IBehaviourController behaviourController, params object?[]? args)
+            where TOriginal : class
+            where TFallback : class, IBehaviour, TOriginal
+        => behaviourController.GetBehaviour<TOriginal>() ?? behaviourController.AddBehaviour<TFallback>(args);
+
     /// <summary>
     /// Tries to get a <see cref="IBehaviour"/> of the specified type in it's <see cref="IUniverseObject"/>'s parents recursively.
     /// </summary>