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Src/Core/StateMachine/AsyncStateMachine.cs

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+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Cysharp.Threading.Tasks;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace BITKit.StateMachine
+{
+    /// <summary>
+    /// 动态异步状态机
+    /// </summary>
+    /// <typeparam name="T">异步状态</typeparam>
+    public class AsyncStateMachine<T>:IStateMachine<T> ,IDisposable where T  : IStateAsync
+    {
+        private enum AsyncState
+        {
+            None,
+            Initializing,
+            InEntering,
+            InExiting,
+            InUpdating,
+        }
+        private readonly IServiceCollection _serviceCollection;
+        public AsyncStateMachine(IServiceCollection serviceCollection)
+        {
+            _serviceCollection = serviceCollection;
+        }
+        public bool Enabled { get; set; }
+        public T CurrentState { get; set; }
+        private T _nextState;
+        public event Action<T, T> OnStateChanging; 
+        public event Action<T, T> OnStateChanged;
+        public event Action<T> OnStateRegistered;
+        public event Action<T> OnStateUnRegistered;
+        public IDictionary<Type, T> StateDictionary { get; } = new Dictionary<Type, T>();
+        private AsyncState _currentState;
+        private Task _currentTask;
+        private readonly CancellationTokenSource _cancellationTokenSource=new();
+        public async void Initialize()
+        {
+            if (_currentState is not AsyncState.None)
+            {
+                throw new InvalidOperationException("状态机可能已初始化");
+            }
+
+            _currentState = AsyncState.Initializing;
+            foreach (var (type,value) in StateDictionary)
+            {
+               await value.InitializeAsync();
+            }
+            foreach (var (type,value) in StateDictionary)
+            {
+                value.Initialize();
+            }
+            _currentState = AsyncState.None;
+        }
+
+        public void UpdateState(float deltaTime)
+        {
+            if(_cancellationTokenSource.IsCancellationRequested)return;
+            switch (_currentState)
+            {
+                case AsyncState.None:
+                    if (_nextState is not null)
+                    {
+                        _currentState = AsyncState.InEntering;
+                        _currentTask = CurrentState.OnStateEntryAsync(CurrentState).AsTask();
+                        
+                        OnStateChanging?.Invoke(CurrentState,_nextState);
+                        return;
+                    }
+                    _currentState = AsyncState.InUpdating;
+                    if (CurrentState is not null)
+                    {
+                        _currentTask = CurrentState.OnStateUpdateAsync(deltaTime).AsTask();
+                    }
+                    break;
+                case AsyncState.InExiting:
+                    if (_currentTask.IsCompleted)
+                    {
+                        _currentState =_nextState is not null ? AsyncState.InEntering : AsyncState.None;
+                        CurrentState.OnStateExit(CurrentState,_nextState);
+                        if (_nextState is not null)
+                        {
+                            _currentTask = _nextState.OnStateEntryAsync(_nextState).AsTask();
+                        }
+                    }
+                    break;
+                case AsyncState.InEntering:
+                    if (_currentTask.IsCompleted)
+                    {
+                        _currentState = AsyncState.None;
+                        _nextState.OnStateEntry(CurrentState);
+                        
+                        OnStateChanged?.Invoke(CurrentState,_nextState);
+                        
+                        CurrentState = _nextState;
+                        _nextState = default;
+                    }
+                    break;
+                case AsyncState.InUpdating:
+                    if (_currentTask.IsCompleted)
+                    {
+                        _currentTask = null;
+                        _currentState = AsyncState.None;
+                    }
+                    break;
+            }
+        }
+
+        public void DisposeState()
+        {
+    
+        }
+        
+        public void TransitionState<State>() where State : T
+        {
+            throw new InvalidOperationException("动态异步状态机不支持,请使用TransitionAsync");
+        }
+        public void TransitionState(T state)
+        {
+        }
+
+        public void Dispose()
+        {
+            _cancellationTokenSource.Cancel();
+            _cancellationTokenSource.Dispose();
+        }
+    }
+
+}