feat: IActive interface added for hierarchy active state

Engine.Core/BaseEntity.cs

@@ -0,0 +1,111 @@
+using System;
+
+namespace Syntriax.Engine.Core.Abstract;
+
+public abstract class BaseEntity : IEntity
+{
+    public event IEntity.IdChangedEventHandler? OnIdChanged = null;
+
+    public event IInitializable.InitializedEventHandler? OnInitialized = null;
+    public event IInitializable.FinalizedEventHandler? OnFinalized = null;
+
+    public event IHasStateEnable.StateEnableAssignedEventHandler? OnStateEnableAssigned = null;
+    public event IAssignable.UnassignEventHandler? OnUnassigned = null;
+
+    private IStateEnable _stateEnable = null!;
+
+    private bool _initialized = false;
+    private string _id = string.Empty;
+
+    public virtual IStateEnable StateEnable => _stateEnable;
+
+    public string Id
+    {
+        get => _id;
+        set
+        {
+            if (IsInitialized)
+                throw new($"Can't change {nameof(Id)} of {_id} because it's initialized");
+
+            if (value == _id)
+                return;
+
+            string previousId = _id;
+
+            _id = value;
+            OnIdChanged?.Invoke(this, previousId);
+        }
+    }
+
+    public bool IsInitialized
+    {
+        get => _initialized;
+        private set
+        {
+            if (value == _initialized)
+                return;
+
+            _initialized = value;
+            if (value)
+                OnInitialized?.Invoke(this);
+            else
+                OnFinalized?.Invoke(this);
+        }
+    }
+
+    protected virtual void OnAssign(IStateEnable stateEnable) { }
+    public bool Assign(IStateEnable stateEnable)
+    {
+        if (IsInitialized)
+            return false;
+
+        _stateEnable = stateEnable;
+        _stateEnable.Assign(this);
+        OnAssign(stateEnable);
+        OnStateEnableAssigned?.Invoke(this);
+        return true;
+    }
+
+    protected virtual void UnassignInternal() { }
+    public bool Unassign()
+    {
+        if (IsInitialized)
+            return false;
+
+        UnassignInternal();
+
+        _stateEnable = null!;
+        _stateEnable.Unassign();
+        OnUnassigned?.Invoke(this);
+        return true;
+    }
+
+    protected virtual void InitializeInternal() { }
+    public bool Initialize()
+    {
+        if (IsInitialized)
+            return false;
+
+        _stateEnable ??= Factory.StateEnableFactory.Instantiate(this);
+
+        InitializeInternal();
+
+        IsInitialized = true;
+        return true;
+    }
+
+    protected virtual void FinalizeInternal() { }
+    public bool Finalize()
+    {
+        if (!IsInitialized)
+            return false;
+
+        FinalizeInternal();
+
+        IsInitialized = false;
+        return true;
+    }
+
+    protected BaseEntity() => _id = Guid.NewGuid().ToString("D");
+    protected BaseEntity(string id) => _id = id;
+}