Update iso-prototype.py

src/iso-prototype.py

@@ -399,40 +399,65 @@ def ensure_parent_directories(iso, logical: PurePosixPath) -> None:
         iso.add_directory(**namespace_kwargs(iso, current, is_dir=True))
 
 
-def remove_logical(iso, logical: PurePosixPath) -> bool:
-    found = find_existing_record(iso, logical)
-    if not found:
-        return False
-
-    # rm_file() removes the file and all of its linked namespace records even
-    # when only one valid path is supplied. Passing ISO9660, Joliet, and UDF
-    # paths together is fragile because their spellings need not map exactly
-    # to the same internal record on imported Microsoft media.
+def remove_found_record(iso, found: dict[str, str]) -> None:
+    # rm_file() removes the inode and all linked namespace records when called
+    # through any one path that actually exists.
     for namespace in ("udf_path", "joliet_path", "iso_path"):
         candidate = found.get(namespace)
         if candidate is None:
             continue
         iso.rm_file(**{namespace: candidate})
-        return True
+        return
 
-    return False
+    raise PrototypeError("No usable namespace path was found for removal")
 
 
-def add_file_all_namespaces(iso, source: Path, logical: PurePosixPath) -> None:
-    ensure_parent_directories(iso, logical)
-    iso.add_file(str(source), **namespace_kwargs(iso, logical))
+def remove_logical(iso, logical: PurePosixPath) -> bool:
+    found = find_existing_record(iso, logical)
+    if not found:
+        return False
+    remove_found_record(iso, found)
+    return True
+
+
+def add_file_all_namespaces(
+    iso,
+    source: Path,
+    logical: PurePosixPath,
+    paths: dict[str, str] | None = None,
+) -> None:
+    if paths is None:
+        ensure_parent_directories(iso, logical)
+        paths = namespace_kwargs(iso, logical)
+
+    if not paths:
+        raise PrototypeError(f"No namespace paths available for {logical}")
+
+    iso.add_file(str(source), **paths)
 
 
 def sync_file(iso, tree: Path, logical: PurePosixPath) -> None:
     source = tree / str(logical).lstrip("/")
     if not source.is_file():
         raise PrototypeError(f"Replacement does not exist: {source}")
-    removed = remove_logical(iso, logical)
-    if not removed:
+
+    # Preserve the exact namespaces and spellings imported from the source ISO.
+    # Some Microsoft media expose a file through UDF/Joliet but not through the
+    # ISO9660 tree. Reconstructing all three paths can therefore reference a
+    # parent directory that does not exist and makes PyCdlib raise
+    # "Could not find path".
+    found = find_existing_record(iso, logical)
+    if not found:
         raise PrototypeError(
             f"Cannot map existing file {logical} in ISO9660, Joliet, or UDF; refusing replacement"
         )
-    add_file_all_namespaces(iso, source, logical)
+
+    print("  Existing namespace paths:")
+    for namespace, path in found.items():
+        print(f"    {namespace}: {path}")
+
+    remove_found_record(iso, found)
+    add_file_all_namespaces(iso, source, logical, found)
 
 
 def sync_tree(iso, tree: Path, logical_root: PurePosixPath) -> None: