fix directory hardlink transfer

README.md

@@ -407,6 +407,10 @@ MediaStationGo 支持 Telegram Bot 绑定、用户菜单、群组管理菜单和
 
 确认 qBittorrent 保存路径已经通过 `volumes` 挂载进 MediaStationGo 容器，并且 `MEDIASTATION_DOWNLOAD_DIR` 与 `MEDIASTATION_DOWNLOAD_CONTAINER_DIR` 对应正确。
 
+**硬链接目录在 Docker / NAS 上看不到内容？**
+
+硬链接不能直接链接“目录”本身，只能链接目录里的文件。文件管理器执行目录硬链接时会递归创建目标目录结构，并为每个文件创建硬链接。硬链接还要求源文件和目标文件在容器内属于同一个文件系统/子卷；如果下载目录和媒体目录是两个独立 bind mount、不同硬盘、不同 btrfs 子卷或网盘挂载，系统会返回 `invalid cross-device link`，此时请选择“复制”或“软链接”。
+
 **第三方播放器无法连接？**
 
 确认播放器填写的是 `http://服务器IP:18080`，账号密码使用 MediaStationGo 用户账号。反代部署时需要正确设置外部访问地址和 HTTPS 头。

README_EN.md

@@ -510,6 +510,12 @@ Beginners should not. Editing `docker-compose.yml` directly is easier to underst
 | Operations | Task queue, recycle bin, duplicate files, notifications, logs |
 | AI | OpenAI-compatible API, AI search, recommendations, assistant |
 
+Directory hardlinks are handled by recreating the directory tree and hardlinking
+each contained file. Linux cannot hardlink a directory itself. Hardlinks still
+require the source and target files to be on the same filesystem/subvolume from
+inside the container; if media and downloads are separate bind mounts, disks,
+btrfs subvolumes, or cloud mounts, use copy or symlink instead.
+
 ## Development
 
 Regular users should use Docker. Developers can run:

internal/service/filemanager.go

@@ -193,9 +193,6 @@ func (s *FileManagerService) Transfer(sourcePath, destDir string, mode TransferM
 	if err != nil {
 		return nil, err
 	}
-	if info.IsDir() {
-		return nil, errors.New("directory transfer is not supported yet")
-	}
 	dst := filepath.Join(dstDir, filepath.Base(src))
 	if !s.withinAllowed(dst, roots) {
 		return nil, ErrPathOutOfBounds
@@ -206,7 +203,11 @@ func (s *FileManagerService) Transfer(sourcePath, destDir string, mode TransferM
 	if mode == "" {
 		mode = TransferCopy
 	}
-	if err := transferFile(src, dst, mode); err != nil {
+	if info.IsDir() {
+		if err := transferDirectory(src, dst, mode); err != nil {
+			return nil, err
+		}
+	} else if err := transferFile(src, dst, mode); err != nil {
 		return nil, err
 	}
 	return &FileOperationResult{Path: dst}, nil

internal/service/filemanager_test.go

@@ -93,6 +93,58 @@ func TestFileManagerRecursiveListAndMutations(t *testing.T) {
 	}
 }
 
+func TestFileManagerTransferDirectoryHardlinksFiles(t *testing.T) {
+	root := t.TempDir()
+	if hardlinksUnsupported(t, root) {
+		t.Skip("hardlinks unsupported on this filesystem")
+	}
+	sourceDir := filepath.Join(root, "downloads", "Show")
+	seasonDir := filepath.Join(sourceDir, "Season 01")
+	targetRoot := filepath.Join(root, "media")
+	if err := os.MkdirAll(seasonDir, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.MkdirAll(targetRoot, 0o755); err != nil {
+		t.Fatal(err)
+	}
+	sourceFile := filepath.Join(seasonDir, "Show.S01E01.mkv")
+	if err := os.WriteFile(sourceFile, []byte("episode"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	svc := newFileManagerTestService(t, root)
+
+	res, err := svc.Transfer(sourceDir, targetRoot, TransferHardlink)
+	if err != nil {
+		t.Fatal(err)
+	}
+	targetFile := filepath.Join(res.Path, "Season 01", "Show.S01E01.mkv")
+	sourceInfo, err := os.Stat(sourceFile)
+	if err != nil {
+		t.Fatal(err)
+	}
+	targetInfo, err := os.Stat(targetFile)
+	if err != nil {
+		t.Fatalf("hardlinked directory file missing: %v", err)
+	}
+	if !os.SameFile(sourceInfo, targetInfo) {
+		t.Fatal("directory hardlink should hardlink contained files")
+	}
+	listing, err := svc.List(res.Path, 100, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	found := false
+	for _, entry := range listing.Entries {
+		if entry.Path == targetFile {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatalf("target directory listing did not include %s", targetFile)
+	}
+}
+
 func TestFileManagerRefusesRootMutation(t *testing.T) {
 	root := t.TempDir()
 	svc := newFileManagerTestService(t, root)
@@ -101,6 +153,19 @@ func TestFileManagerRefusesRootMutation(t *testing.T) {
 	}
 }
 
+func hardlinksUnsupported(t *testing.T, root string) bool {
+	t.Helper()
+	src := filepath.Join(root, "hardlink-probe-src")
+	dst := filepath.Join(root, "hardlink-probe-dst")
+	if err := os.WriteFile(src, []byte("probe"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	err := os.Link(src, dst)
+	_ = os.Remove(src)
+	_ = os.Remove(dst)
+	return err != nil
+}
+
 func TestFileManagerIncludesConfiguredOrganizeRoots(t *testing.T) {
 	root := t.TempDir()
 	sourceDir := filepath.Join(root, "downloads")

internal/service/transfer.go

@@ -134,3 +134,52 @@ func moveFile(src, dst string) error {
 	}
 	return os.Remove(src)
 }
+
+func transferDirectory(src, dst string, mode TransferMode) error {
+	if _, err := os.Stat(dst); err == nil {
+		return fmt.Errorf("destination already exists: %s", dst)
+	}
+	switch mode {
+	case TransferSymlink:
+		return transferFile(src, dst, mode)
+	case TransferMove:
+		if err := os.Rename(src, dst); err == nil {
+			return nil
+		}
+		if err := transferDirectoryTree(src, dst, TransferCopy); err != nil {
+			return err
+		}
+		return os.RemoveAll(src)
+	case TransferHardlink, TransferCopy:
+		return transferDirectoryTree(src, dst, mode)
+	default:
+		return transferDirectory(src, dst, TransferMove)
+	}
+}
+
+func transferDirectoryTree(src, dst string, mode TransferMode) error {
+	if err := filepath.WalkDir(src, func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		rel, err := filepath.Rel(src, path)
+		if err != nil {
+			return err
+		}
+		if rel == "." {
+			return os.MkdirAll(dst, 0o755) // #nosec G301 -- media folders must remain readable by local players.
+		}
+		target := filepath.Join(dst, rel)
+		if d.IsDir() {
+			return os.MkdirAll(target, 0o755) // #nosec G301 -- media folders must remain readable by local players.
+		}
+		if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil { // #nosec G301 -- media folders must remain readable by local players.
+			return err
+		}
+		return transferFile(path, target, mode)
+	}); err != nil {
+		_ = os.RemoveAll(dst)
+		return err
+	}
+	return nil
+}