refactor: split virtual fs mapping and search modules

domain/virtual_fs/common.py

@@ -0,0 +1,44 @@
+from __future__ import annotations
+
+from pathlib import Path
+from typing import Any
+
+from fastapi import HTTPException
+
+
+class VirtualFSCommonMixin:
+    CROSS_TRANSFER_TEMP_ROOT = Path("data/tmp/cross_transfer")
+    DIRECT_REDIRECT_CONFIG_KEY = "enable_direct_download_307"
+
+    @staticmethod
+    def _normalize_path(path: str) -> str:
+        return path if path.startswith("/") else f"/{path}"
+
+    @staticmethod
+    def _build_absolute_path(mount_path: str, rel_path: str) -> str:
+        rel_norm = rel_path.lstrip("/")
+        mount_norm = mount_path.rstrip("/")
+        if not mount_norm:
+            return "/" + rel_norm if rel_norm else "/"
+        return f"{mount_norm}/{rel_norm}" if rel_norm else mount_norm
+
+    @staticmethod
+    def _join_rel(base: str, name: str) -> str:
+        if not base:
+            return name.lstrip("/")
+        if not name:
+            return base
+        return f"{base.rstrip('/')}/{name.lstrip('/')}"
+
+    @staticmethod
+    def _parent_rel(rel: str) -> str:
+        if not rel or "/" not in rel:
+            return ""
+        return rel.rsplit("/", 1)[0]
+
+    @staticmethod
+    async def _ensure_method(adapter: Any, method: str):
+        func = getattr(adapter, method, None)
+        if not callable(func):
+            raise HTTPException(501, detail=f"Adapter does not implement {method}")
+        return func