修复收藏等问题

ruoyi-admin/src/main/java/com/ruoyi/web/controller/client/MusicController.java

@@ -108,6 +108,9 @@ public class MusicController extends BaseController {
     @RequestMapping("/getMusicInfo/{musicId}")
     public AjaxResult getMusicInfo(@PathVariable String musicId){
         Long userId = SecurityUtils.getUserId();
+        if (userId == null){
+            return AjaxResult.error(401,"用户未登录或用户ID为空");
+        }
         MusicInfo musicInfo = musicService.getMusicInfo(userId, musicId);
         if (musicInfo != null){
             return AjaxResult.success(musicInfo);
@@ -136,6 +139,30 @@ public class MusicController extends BaseController {
     }
 
 
+    /**
+     * 获取上一首播放的音乐ID
+     * @param playMode 播放模式：1-顺序播放，2-随机播放
+     * @param playlistType 播放列表类型：1-历史播放，2-分类播放，3-推荐播放，4-收藏播放，5-喜欢播放
+     * @param categoryId 分类ID，当playlistType=2时必填
+     * @param collectId 收藏ID，当playlistType=4时必填
+     * @param reId 推荐ID，当playlistType=3时必填
+     * @param currentMusicId 当前播放的音乐ID，用于顺序播放时获取上一首
+     * @return 上一首音乐ID
+     */
+    @GetMapping("/getPrevMusicId")
+    public AjaxResult getPrevMusicId(@RequestParam(defaultValue = "1") Integer playMode,
+                                    @RequestParam Integer playlistType,
+                                    @RequestParam(required = false) String categoryId,
+                                    @RequestParam(required = false) String collectId,
+                                    @RequestParam(required = false) String reId,
+                                    @RequestParam(required = false) String currentMusicId){
+        Long userId = SecurityUtils.getUserId();
+        String prevMusicId = musicService.getPrevMusicId(userId, playMode, playlistType, categoryId, collectId, reId,currentMusicId);
+        Map<String,Object> result = new HashMap<>();
+        result.put("musicId",prevMusicId);
+        return AjaxResult.success("请求成功",result);
+    }
+
     /**
      * 获取下一首播放的音乐ID
      * @param playMode 播放模式：1-顺序播放，2-随机播放