From fed288859f629025a8588fb689b23fa0d2c2fa36 Mon Sep 17 00:00:00 2001
From: Syntriax <syntriax@gmail.com>
Date: Tue, 6 Feb 2024 12:47:58 +0300
Subject: [PATCH] feat: IAssignableGameObject to ITransform

I originally didn't want ITransform to have a reference to any IGameObject, since it didn't seem necessary to couple these two, and to make ITransform more flexible and reusable but without it we can't get a reference to the IGameObject(s) that's using that ITransform without doing some very stupid workarounds. I'll try to find a better way for this.
---
 Engine.Core/Abstract/ITransform.cs       |  2 +-
 Engine.Core/Factory/GameObjectFactory.cs |  3 +++
 Engine.Core/Transform.cs                 | 27 +++++++++++++++++++++++-
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/Engine.Core/Abstract/ITransform.cs b/Engine.Core/Abstract/ITransform.cs
index 724bc4a..f78adb8 100644
--- a/Engine.Core/Abstract/ITransform.cs
+++ b/Engine.Core/Abstract/ITransform.cs
@@ -6,7 +6,7 @@ namespace Syntriax.Engine.Core.Abstract;
 /// <summary>
 /// Represents the transformation properties of an object such as position, scale, and rotation.
 /// </summary>
-public interface ITransform : IEnumerable<ITransform>
+public interface ITransform : IAssignableGameObject, IEnumerable<ITransform>
 {
     /// <summary>
     /// Event triggered when the <see cref="Position"/> of the <see cref="ITransform"/> changes.
diff --git a/Engine.Core/Factory/GameObjectFactory.cs b/Engine.Core/Factory/GameObjectFactory.cs
index f53ea9e..6713d39 100644
--- a/Engine.Core/Factory/GameObjectFactory.cs
+++ b/Engine.Core/Factory/GameObjectFactory.cs
@@ -22,6 +22,9 @@ public class GameObjectFactory
         behaviourController ??= TypeFactory.Get<BehaviourController>();
         stateEnable ??= TypeFactory.Get<StateEnable>();
 
+        if (!transform.Assign(gameObject))
+            throw AssignException.From(transform, gameObject);
+
         if (!behaviourController.Assign(gameObject))
             throw AssignException.From(behaviourController, gameObject);
         if (!stateEnable.Assign(gameObject))
diff --git a/Engine.Core/Transform.cs b/Engine.Core/Transform.cs
index 4a0c54d..6007b34 100644
--- a/Engine.Core/Transform.cs
+++ b/Engine.Core/Transform.cs
@@ -6,9 +6,13 @@ using Syntriax.Engine.Core.Abstract;
 
 namespace Syntriax.Engine.Core;
 
-[System.Diagnostics.DebuggerDisplay("Position: {Position.ToString(), nq}, Scale: {Scale.ToString(), nq}, Rotation: {Rotation}")]
+[System.Diagnostics.DebuggerDisplay("Name: {GameObject.Name, nq} Position: {Position.ToString(), nq}, Scale: {Scale.ToString(), nq}, Rotation: {Rotation}")]
 public class Transform : ITransform
 {
+    public Action<IAssignableGameObject>? OnGameObjectAssigned { get; set; } = null;
+
+    public Action<IAssignable>? OnUnassigned { get; set; } = null;
+
     public Action<ITransform>? OnPositionChanged { get; set; } = null;
     public Action<ITransform>? OnScaleChanged { get; set; } = null;
     public Action<ITransform>? OnRotationChanged { get; set; } = null;
@@ -28,6 +32,7 @@ public class Transform : ITransform
 
     private readonly List<ITransform> _children = [];
 
+    public IGameObject GameObject { get; private set; } = null!;
     public ITransform? Parent { get; private set; } = null;
 
     public IReadOnlyList<ITransform> Children => _children;
@@ -245,4 +250,24 @@ public class Transform : ITransform
         else
             _rotation = Parent.Rotation + LocalRotation;
     }
+
+    public bool Assign(IGameObject gameObject)
+    {
+        if (GameObject is not null && GameObject.Initialized)
+            return false;
+
+        GameObject = gameObject;
+        OnGameObjectAssigned?.Invoke(this);
+        return true;
+    }
+
+    public bool Unassign()
+    {
+        if (GameObject is not null && GameObject.Initialized)
+            return false;
+
+        GameObject = null!;
+        OnUnassigned?.Invoke(this);
+        return true;
+    }
 }