店铺问答讨论优化：判断当前用户。

alien-store-platform/src/main/java/shop/alien/storeplatform/service/impl/StorePlatformDiscussionServiceImpl.java

@@ -56,7 +56,7 @@ public class StorePlatformDiscussionServiceImpl extends ServiceImpl<StorePlatfor
          * 删除策略: 1-只删除当前讨论, 2-级联删除所有回复
          * 默认为 2 (级联删除)
          */
-        private Integer defaultDeleteStrategy = 2;
+        private Integer defaultDeleteStrategy = STRATEGY_CASCADE;
 
         public static final int STRATEGY_SINGLE = 1;
         public static final int STRATEGY_CASCADE = 2;
@@ -187,6 +187,11 @@ public class StorePlatformDiscussionServiceImpl extends ServiceImpl<StorePlatfor
     @Override
     @Transactional(rollbackFor = Exception.class)
     public boolean postTopic(StorePlatformDiscussion discussion) {
+        Integer currentUserId = LoginUserUtil.getCurrentUserId();
+        if (currentUserId == null) {
+            throw new RuntimeException("请先登录再发表讨论");
+        }
+        discussion.setUserId(currentUserId);
         discussion.setParentId(0);
         discussion.setRootId(0);
         discussion.setLikeCount(0); // 初始化点赞数
@@ -202,6 +207,12 @@ public class StorePlatformDiscussionServiceImpl extends ServiceImpl<StorePlatfor
     @Override
     @Transactional(rollbackFor = Exception.class)
     public boolean postReply(StorePlatformDiscussion discussion) {
+        Integer currentUserId = LoginUserUtil.getCurrentUserId();
+        if (currentUserId == null) {
+            throw new RuntimeException("请先登录再发表回复");
+        }
+        discussion.setUserId(currentUserId);
+
         if (discussion.getParentId() == null || discussion.getParentId() == 0) {
             throw new RuntimeException("回复必须指定父级讨论 ID");
         }
@@ -260,6 +271,12 @@ public class StorePlatformDiscussionServiceImpl extends ServiceImpl<StorePlatfor
             return false;
         }
 
+        // 权限校验：只能删除自己发表的讨论
+        Integer currentUserId = LoginUserUtil.getCurrentUserId();
+        if (currentUserId == null || !currentUserId.equals(discussion.getUserId())) {
+            throw new RuntimeException("无权删除他人发表的讨论");
+        }
+
         // 使用配置中的默认策略
         int finalStrategy = discussionConfig.getDefaultDeleteStrategy();