Core: Detect and account for apworlds being downloaded with a (1) in …

…their name (#4144)

* Core: Detect and account for apworlds being downloaded with a (1) in their name

* Reword comment

* Always use internal module name

* Requested changes from black-silver

worlds/LauncherComponents.py

@@ -100,10 +100,16 @@ def _install_apworld(apworld_src: str = "") -> Optional[Tuple[pathlib.Path, path
 
     apworld_path = pathlib.Path(apworld_src)
 
-    module_name = pathlib.Path(apworld_path.name).stem
     try:
         import zipfile
-        zipfile.ZipFile(apworld_path).open(module_name + "/__init__.py")
+        zip = zipfile.ZipFile(apworld_path)
+        directories = [f.filename.strip('/') for f in zip.filelist if f.CRC == 0 and f.file_size == 0 and f.filename.count('/') == 1]
+        if len(directories) == 1 and directories[0] in apworld_path.stem:
+            module_name = directories[0]
+            apworld_name = module_name + ".apworld"
+        else:
+            raise Exception("APWorld appears to be invalid or damaged. (expected a single directory)")
+        zip.open(module_name + "/__init__.py")
     except ValueError as e:
         raise Exception("Archive appears invalid or damaged.") from e
     except KeyError as e:
@@ -122,7 +128,7 @@ def _install_apworld(apworld_src: str = "") -> Optional[Tuple[pathlib.Path, path
     # TODO: run generic test suite over the apworld.
     # TODO: have some kind of version system to tell from metadata if the apworld should be compatible.
 
-    target = pathlib.Path(worlds.user_folder) / apworld_path.name
+    target = pathlib.Path(worlds.user_folder) / apworld_name
     import shutil
     shutil.copyfile(apworld_path, target)