Refactor file data format determination

Author: ncoghlan

src/lmstudio/history.py

@@ -18,7 +18,6 @@
     Sequence,
     Tuple,
     TypeAlias,
-    Union,
     cast,
     get_args as get_typeform_args,
     runtime_checkable,
@@ -540,39 +539,33 @@ def add_tool_result(self, result: ToolCallResultInput) -> ToolResultMessage:
 
 def _get_file_details(src: LocalFileInput) -> Tuple[str, Buffer]:
     """Read file contents as binary data and generate a suitable default name."""
-    # Try to handle buffer protocol objects first (unless it's a path)
-    if not isinstance(src, (str, os.PathLike)) and not hasattr(src, "read"):
-        try:
+    data: Buffer
+    if isinstance(src, Buffer):
+        if isinstance(src, memoryview):
             # If already a memoryview, just use it directly
-            if isinstance(src, memoryview):
-                data: Buffer = src
-            else:
-                # Try to create a memoryview - this will work for any buffer protocol object
-                # including bytes, bytearray, array.array, numpy arrays, etc.
-                data = memoryview(src)
-            name = str(uuid.uuid4())
-            return name, data
-        except TypeError:
-            # Not a buffer protocol object, fall through to other checks
-            pass
-
-    if hasattr(src, "read"):
+            data = src
+        else:
+            # Try to create a memoryview - this will work for any buffer protocol object
+            # including bytes, bytearray, array.array, numpy arrays, etc.
+            data = memoryview(src)
+        # Received raw file data without any name information
+        name = str(uuid.uuid4())
+    elif hasattr(src, "read"):
         try:
             data = src.read()
         except OSError as exc:
             # Note: OSError details remain available via raised_exc.__context__
             err_msg = f"Error while reading {src!r} ({exc!r})"
             raise LMStudioOSError(err_msg) from None
         name = getattr(src, "name", str(uuid.uuid4()))
-        # data is bytes here, which is a Buffer type
-        return name, data
     else:
         # At this point, src must be a path-like object
-        src_path_input = cast(Union[str, os.PathLike[str]], src)
         try:
-            src_path = Path(src_path_input)
+            src_path = Path(src)
         except Exception as exc:
-            err_msg = f"Expected file-like object, filesystem path, or buffer ({exc!r})"
+            err_msg = (
+                f"Expected file-like object, filesystem path, or data buffer ({exc!r})"
+            )
             raise LMStudioValueError(err_msg) from None
         try:
             data = src_path.read_bytes()
@@ -581,8 +574,7 @@ def _get_file_details(src: LocalFileInput) -> Tuple[str, Buffer]:
             err_msg = f"Error while reading {str(src_path)!r} ({exc!r})"
             raise LMStudioOSError(err_msg) from None
         name = str(src_path.name)
-        # data is bytes here, which is a Buffer type
-        return name, data
+    return name, data
 
 
 _ContentHash: TypeAlias = bytes