From 90370a2b43d7465324d2530e3931a11e3a9731c7 Mon Sep 17 00:00:00 2001
From: Syntriax <syntriax@gmail.com>
Date: Tue, 29 Oct 2024 23:14:08 +0300
Subject: [PATCH] feat: Physics Coroutine Manager

---
 Engine.Physics2D/PhysicsCoroutineManager.cs  | 62 ++++++++++++++++++++
 Engine.Physics2D/PhysicsEngine2DCollector.cs | 40 +------------
 2 files changed, 65 insertions(+), 37 deletions(-)
 create mode 100644 Engine.Physics2D/PhysicsCoroutineManager.cs

diff --git a/Engine.Physics2D/PhysicsCoroutineManager.cs b/Engine.Physics2D/PhysicsCoroutineManager.cs
new file mode 100644
index 0000000..8bda9db
--- /dev/null
+++ b/Engine.Physics2D/PhysicsCoroutineManager.cs
@@ -0,0 +1,62 @@
+using System.Collections;
+using System.Collections.Generic;
+
+using Syntriax.Engine.Core;
+using Syntriax.Engine.Core.Abstract;
+using Syntriax.Engine.Physics2D.Abstract;
+
+namespace Engine.Physics2D;
+
+public class PhysicsCoroutineManager : HierarchyObjectBase
+{
+    private readonly List<IEnumerator> enumerators = [];
+    private IPhysicsEngine2D? physicsEngine = null;
+
+
+    public IEnumerator CreateCoroutine(IEnumerator enumerator)
+    {
+        enumerators.Add(enumerator);
+        return enumerator;
+    }
+
+    public void StopCoroutine(IEnumerator enumerator)
+    {
+        enumerators.Remove(enumerator);
+    }
+
+    protected override void OnEnteringHierarchy(IGameManager gameManager)
+    {
+        physicsEngine = gameManager.HierarchyObjects.FindObject<IPhysicsEngine2D>();
+        if (physicsEngine is IPhysicsEngine2D foundPhysicsEngine)
+            foundPhysicsEngine.OnPhysicsStep += OnPhysicsStep;
+        else
+            gameManager.OnUpdate += OnUpdate;
+    }
+
+    private void OnPhysicsStep(IPhysicsEngine2D sender, float stepDeltaTime)
+    {
+        for (int i = enumerators.Count - 1; i >= 0; i--)
+            if (!enumerators[i].MoveNext())
+                enumerators.RemoveAt(i);
+    }
+
+    protected override void OnExitingHierarchy(IGameManager gameManager)
+    {
+        if (physicsEngine is IPhysicsEngine2D existingPhysicsEngine)
+            existingPhysicsEngine.OnPhysicsStep -= OnPhysicsStep;
+        gameManager.OnUpdate -= OnUpdate;
+    }
+
+    private void OnUpdate(IGameManager sender, EngineTime time)
+    {
+        if (GameManager is not IGameManager gameManager)
+            return;
+
+        physicsEngine = gameManager.HierarchyObjects.FindObject<IPhysicsEngine2D>();
+        if (physicsEngine is IPhysicsEngine2D foundPhysicsEngine)
+        {
+            foundPhysicsEngine.OnPhysicsStep += OnPhysicsStep;
+            gameManager.OnUpdate -= OnUpdate;
+        }
+    }
+}
diff --git a/Engine.Physics2D/PhysicsEngine2DCollector.cs b/Engine.Physics2D/PhysicsEngine2DCollector.cs
index d89c1b8..0f6abc2 100644
--- a/Engine.Physics2D/PhysicsEngine2DCollector.cs
+++ b/Engine.Physics2D/PhysicsEngine2DCollector.cs
@@ -4,11 +4,8 @@ using Syntriax.Engine.Physics2D.Abstract;
 
 namespace Syntriax.Engine.Physics2D;
 
-public class PhysicsEngine2DCollector : IPhysicsEngine2D, IAssignableGameManager
+public class PhysicsEngine2DCollector : HierarchyObjectBase, IPhysicsEngine2D
 {
-    public event IAssignable.OnUnassignedDelegate? OnUnassigned = null;
-    public event IAssignableGameManager.OnGameManagerAssignedDelegate? OnGameManagerAssigned = null;
-
     public event IPhysicsEngine2D.OnPhysicsIterationDelegate? OnPhysicsIteration = null;
     public event IPhysicsEngine2D.OnPhysicsStepDelegate? OnPhysicsStep = null;
 
@@ -23,7 +20,6 @@ public class PhysicsEngine2DCollector : IPhysicsEngine2D, IAssignableGameManager
 
 
     public int IterationPerStep { get => _iterationPerStep; set => _iterationPerStep = value < 1 ? 1 : value; }
-    public IGameManager GameManager { get; private set; } = null!;
 
     public void Step(float deltaTime)
     {
@@ -102,34 +98,18 @@ public class PhysicsEngine2DCollector : IPhysicsEngine2D, IAssignableGameManager
         rigidBody.Transform.Position += rigidBody.Velocity * intervalDeltaTime;
         rigidBody.Transform.Rotation += rigidBody.AngularVelocity * intervalDeltaTime;
     }
-
-    public bool Assign(IGameManager gameManager)
+    protected override void OnEnteringHierarchy(IGameManager gameManager)
     {
-        if (GameManager is not null)
-            return false;
-
         physicsUpdateCollector.Assign(gameManager);
         colliderCollector.Assign(gameManager);
         rigidBodyCollector.Assign(gameManager);
-
-        GameManager = gameManager;
-        OnGameManagerAssigned?.Invoke(this);
-
-        return true;
     }
 
-    public bool Unassign()
+    protected override void OnExitingHierarchy(IGameManager gameManager)
     {
-        if (GameManager is null)
-            return false;
-
         physicsUpdateCollector.Unassign();
         colliderCollector.Unassign();
         rigidBodyCollector.Unassign();
-
-        GameManager = null!;
-        OnUnassigned?.Invoke(this);
-        return true;
     }
 
     public PhysicsEngine2DCollector()
@@ -138,20 +118,6 @@ public class PhysicsEngine2DCollector : IPhysicsEngine2D, IAssignableGameManager
         collisionResolver = new CollisionResolver2D();
     }
 
-    public PhysicsEngine2DCollector(IGameManager gameManager)
-    {
-        Assign(gameManager);
-        collisionDetector = new CollisionDetector2D();
-        collisionResolver = new CollisionResolver2D();
-    }
-
-    public PhysicsEngine2DCollector(IGameManager gameManager, ICollisionDetector2D collisionDetector, ICollisionResolver2D collisionResolver)
-    {
-        Assign(gameManager);
-        this.collisionDetector = collisionDetector;
-        this.collisionResolver = collisionResolver;
-    }
-
     public PhysicsEngine2DCollector(ICollisionDetector2D collisionDetector, ICollisionResolver2D collisionResolver)
     {
         this.collisionDetector = collisionDetector;