多轮审查和修复

Assets/Scripts/Enemies/EnemyStats.cs

@@ -1,29 +1,67 @@
 using UnityEngine;
+using BaseGames.Core;
+using BaseGames.Core.Events;
 
 namespace BaseGames.Enemies
 {
     /// <summary>
     /// 敌人运行时数值组件（架构 07_EnemyModule §2）。
     /// 由 EnemyBase.Awake() 通过 Initialize(EnemyStatsSO) 注入配置。
+    /// 同时订阅难度变更事件，支持游戏进行中切换难度（架构 19 §5）。
     /// </summary>
     public class EnemyStats : MonoBehaviour
     {
         private EnemyStatsSO _config;
 
+        [SerializeField] private DifficultyChangedEventChannel _onDifficultyChanged;
+
         public int   MaxHP               { get; private set; }
         public int   CurrentHP           { get; private set; }
         public int   Defense             { get; private set; }
         public float AttackCooldownTimer { get; private set; }
 
-        /// <summary>每帧由 EnemyBase 更新（读取玩家位置后写入）。</summary>
-        public float DistanceToPlayer    { get; set; }
+        /// <summary>
+        /// 每帧由 EnemyBase 更新（sqrMagnitude，避免 sqrt 开销）。
+        /// 使用方请与 range*range 比较，而非直接与 range 比较。
+        /// </summary>
+        public float SqrDistanceToPlayer { get; set; }
+
+        private readonly CompositeDisposable _subs = new();
+
+        private void OnEnable()
+        {
+            _onDifficultyChanged?.Subscribe(HandleDifficultyChanged).AddTo(_subs);
+        }
+
+        private void OnDisable()
+        {
+            _subs.Clear();
+        }
 
         public void Initialize(EnemyStatsSO so)
         {
-            _config    = so;
-            MaxHP      = so.MaxHP;
-            CurrentHP  = so.MaxHP;
-            Defense    = so.Defense;
+            _config = so;
+            Defense = so.Defense;           // Defense 不随难度缩放（架构 19 §5）
+            ApplyHPScaler();
+            CurrentHP = MaxHP;
+        }
+
+        /// <summary>难度变更时重算 HP（保持 HP 比例，架构 19 §5）。</summary>
+        private void HandleDifficultyChanged(DifficultyLevel _)
+        {
+            if (_config == null) return;
+            float hpRatio = MaxHP > 0 ? (float)CurrentHP / MaxHP : 1f;
+            ApplyHPScaler();
+            CurrentHP = Mathf.Clamp(Mathf.RoundToInt(MaxHP * hpRatio), 1, MaxHP);
+        }
+
+        private void ApplyHPScaler()
+        {
+            if (_config == null) return;
+            var scaler = ServiceLocator.GetOrDefault<IDifficultyService>()?.CurrentScaler;
+            MaxHP = scaler != null
+                ? Mathf.Max(1, Mathf.RoundToInt(_config.MaxHP * scaler.EnemyHPMultiplier))
+                : _config.MaxHP;
         }
 
         public void TakeDamage(int amount)
@@ -39,7 +77,7 @@ namespace BaseGames.Enemies
 
         public void ResetAttackCooldown()
         {
-            AttackCooldownTimer = _config != null ? _config.AttackCooldown : 1f;
+            AttackCooldownTimer = _config.AttackCooldown;
         }
     }
 }