更新 src/main/java/com/vibevault/service/PlaylistServiceImpl.java

src/main/java/com/vibevault/service/PlaylistServiceImpl.java

@@ -14,6 +14,7 @@ import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
 import java.util.List;
+import java.util.stream.Collectors;
 
 /**
  * 歌单服务实现
@@ -37,60 +38,134 @@ public class PlaylistServiceImpl implements PlaylistService {
 
     @Override
     public List<PlaylistDTO> getAllPlaylists() {
-        // TODO: 实现获取所有歌单
+        // 获取所有歌单并转换为DTO
-        throw new UnsupportedOperationException("待实现");
+        return playlistRepository.findAll().stream()
+                .map(this::toDTO)
+                .collect(Collectors.toList());
     }
 
     @Override
     public PlaylistDTO getPlaylistById(Long id) {
-        // TODO: 实现根据 ID 获取歌单，不存在时抛出 ResourceNotFoundException
+        // 根据ID查询歌单，不存在则抛异常
-        throw new UnsupportedOperationException("待实现");
+        Playlist playlist = playlistRepository.findById(id)
+                .orElseThrow(() -> new ResourceNotFoundException("歌单不存在，ID: " + id));
+        return toDTO(playlist);
     }
 
     @Override
     @Transactional
     public PlaylistDTO createPlaylist(String name, String ownerUsername) {
-        // TODO: 实现创建歌单
+        // 1. 查询歌单所有者
-        throw new UnsupportedOperationException("待实现");
+        User owner = userRepository.findByUsername(ownerUsername)
+                .orElseThrow(() -> new ResourceNotFoundException("用户不存在，用户名: " + ownerUsername));
+        
+        // 2. 创建歌单实体
+        Playlist playlist = new Playlist();
+        playlist.setName(name);
+        playlist.setOwner(owner);
+        
+        // 3. 保存歌单并返回DTO
+        Playlist savedPlaylist = playlistRepository.save(playlist);
+        return toDTO(savedPlaylist);
     }
 
     @Override
     @Transactional
-    public PlaylistDTO addSongToPlaylist(Long playlistId, SongCreateDTO song, String username) {
+    public PlaylistDTO addSongToPlaylist(Long playlistId, SongCreateDTO songDTO, String username) {
-        // TODO: 实现添加歌曲到歌单
+        // 1. 查询歌单
-        // [Challenge] 需要检查用户是否有权限操作此歌单
+        Playlist playlist = playlistRepository.findById(playlistId)
-        throw new UnsupportedOperationException("待实现");
+                .orElseThrow(() -> new ResourceNotFoundException("歌单不存在，ID: " + playlistId));
+        
+        // 2. 检查用户权限
+        checkPermission(playlist, username);
+        
+        // 3. 创建歌曲实体
+        Song song = new Song();
+        song.setTitle(songDTO.getTitle());
+        song.setArtist(songDTO.getArtist());
+        song.setDurationInSeconds(songDTO.getDurationInSeconds());
+        song.setPlaylist(playlist);
+        
+        // 4. 维护双向关系并保存
+        playlist.getSongs().add(song);
+        Playlist updatedPlaylist = playlistRepository.save(playlist);
+        
+        return toDTO(updatedPlaylist);
     }
 
     @Override
     @Transactional
     public void removeSongFromPlaylist(Long playlistId, Long songId, String username) {
-        // TODO: 实现从歌单移除歌曲
+        // 1. 查询歌单
-        // [Challenge] 需要检查用户是否有权限操作此歌单
+        Playlist playlist = playlistRepository.findById(playlistId)
-        throw new UnsupportedOperationException("待实现");
+                .orElseThrow(() -> new ResourceNotFoundException("歌单不存在，ID: " + playlistId));
+        
+        // 2. 检查用户权限
+        checkPermission(playlist, username);
+        
+        // 3. 查询歌曲并移除
+        Song song = playlist.getSongs().stream()
+                .filter(s -> s.getId().equals(songId))
+                .findFirst()
+                .orElseThrow(() -> new ResourceNotFoundException("歌曲不存在，ID: " + songId));
+        
+        playlist.getSongs().remove(song);
+        playlistRepository.save(playlist);
     }
 
     @Override
     @Transactional
     public void deletePlaylist(Long playlistId, String username) {
-        // TODO: 实现删除歌单
+        // 1. 查询歌单
-        // [Challenge] 需要检查用户是否有权限操作此歌单
+        Playlist playlist = playlistRepository.findById(playlistId)
-        throw new UnsupportedOperationException("待实现");
+                .orElseThrow(() -> new ResourceNotFoundException("歌单不存在，ID: " + playlistId));
+        
+        // 2. 检查用户权限
+        checkPermission(playlist, username);
+        
+        // 3. 删除歌单
+        playlistRepository.delete(playlist);
     }
 
     // ========== Advanced 方法 ==========
 
     @Override
     public List<PlaylistDTO> searchPlaylists(String keyword) {
-        // TODO [Advanced]: 实现按关键字搜索歌单
+        // 按名称模糊搜索歌单
-        throw new UnsupportedOperationException("待实现");
+        return playlistRepository.findByNameContainingIgnoreCase(keyword).stream()
+                .map(this::toDTO)
+                .collect(Collectors.toList());
     }
 
     @Override
     @Transactional
     public PlaylistDTO copyPlaylist(Long playlistId, String newName, String username) {
-        // TODO [Advanced]: 实现复制歌单
+        // 1. 查询原歌单
-        throw new UnsupportedOperationException("待实现");
+        Playlist original = playlistRepository.findById(playlistId)
+                .orElseThrow(() -> new ResourceNotFoundException("原歌单不存在，ID: " + playlistId));
+        
+       // 2. 查询目标用户（新所有者）
+        User newOwner = userRepository.findByUsername(username)
+                .orElseThrow(() -> new ResourceNotFoundException("用户不存在，用户名: " + username));
+        
+        // 3. 创建新歌单
+        Playlist copy = new Playlist();
+        copy.setName(newName);
+        copy.setOwner(newOwner);
+        
+        // 4. 复制歌曲
+        original.getSongs().forEach(song -> {
+            Song newSong = new Song();
+            newSong.setTitle(song.getTitle());
+            newSong.setArtist(song.getArtist());
+            newSong.setDurationInSeconds(song.getDurationInSeconds());
+            newSong.setPlaylist(copy);
+            copy.getSongs().add(newSong);
+        });
+        
+        // 5. 保存并返回DTO
+        Playlist savedCopy = playlistRepository.save(copy);
+        return toDTO(savedCopy);
     }
 
     // ========== 辅助方法 ==========
@@ -99,16 +174,28 @@ public class PlaylistServiceImpl implements PlaylistService {
      * 将 Playlist 实体转换为 DTO
      */
     private PlaylistDTO toDTO(Playlist playlist) {
-        // TODO: 实现实体到 DTO 的转换
+        List<SongDTO> songDTOs = playlist.getSongs().stream()
-        throw new UnsupportedOperationException("待实现");
+                .map(this::toSongDTO)
+                .collect(Collectors.toList());
+        
+        return new PlaylistDTO(
+                playlist.getId(),
+                playlist.getName(),
+                playlist.getOwner().getUsername(),
+                songDTOs
+        );
     }
 
     /**
      * 将 Song 实体转换为 DTO
      */
     private SongDTO toSongDTO(Song song) {
-        // TODO: 实现实体到 DTO 的转换
+        return new SongDTO(
-        throw new UnsupportedOperationException("待实现");
+                song.getId(),
+                song.getTitle(),
+                song.getArtist(),
+                song.getDurationInSeconds()
+        );
     }
 
     /**
@@ -116,7 +203,17 @@ public class PlaylistServiceImpl implements PlaylistService {
      * 规则：歌单所有者或管理员可以操作
      */
     private void checkPermission(Playlist playlist, String username) {
-        // TODO [Challenge]: 实现权限检查
+        // 查询当前操作的用户
-        // 如果无权限，抛出 UnauthorizedException
+        User operator = userRepository.findByUsername(username)
+                .orElseThrow(() -> new ResourceNotFoundException("操作用户不存在，用户名: " + username));
+        
+        // 权限规则：所有者 或 管理员（假设角色为"ROLE_ADMIN"）
+        boolean isOwner = playlist.getOwner().getUsername().equals(username);
+        boolean isAdmin = "ROLE_ADMIN".equals(operator.getRole());
+        
+        if (!isOwner && !isAdmin) {
+            throw new UnauthorizedException("无权限操作此歌单");
+        }
     }
 }
+