feat(playlist): 实现歌单收藏与取消收藏功能- 添加收藏状态检查逻辑

- 支持取消已收藏的歌单
- 更新歌单收藏计数- 保存用户收藏记录
- 返回收藏操作结果状态

music-houduan/src/main/java/com/test/musichouduan/service/impl/PlaylistServiceImpl.java

@@ -368,10 +368,16 @@ public class PlaylistServiceImpl implements PlaylistService {
 
         // 检查是否已收藏
         if (userCollectPlaylistRepository.existsByUserAndPlaylist(user, playlist)) {
-            throw new BusinessException("已收藏该歌单");
+            // 已收藏则取消收藏
-        }
+            userCollectPlaylistRepository.deleteByUserAndPlaylist(user, playlist);
 
-        // 收藏歌单
+            // 更新收藏数
+            playlist.setCollectCount((playlist.getCollectCount() == null ? 0 : playlist.getCollectCount()) - 1);
+            playlistRepository.save(playlist);
+
+            return false; // 表示取消收藏
+        } else {
+            // 未收藏则进行收藏
             com.test.musichouduan.entity.UserCollectPlaylist userCollectPlaylist = new com.test.musichouduan.entity.UserCollectPlaylist();
             userCollectPlaylist.setUser(user);
             userCollectPlaylist.setPlaylist(playlist);
@@ -381,8 +387,10 @@ public class PlaylistServiceImpl implements PlaylistService {
             playlist.setCollectCount((playlist.getCollectCount() == null ? 0 : playlist.getCollectCount()) + 1);
             playlistRepository.save(playlist);
 
-        return true;
+            return true; // 表示收藏成功
         }
+    }
+
 
     @Override
     @Transactional