+ int tree_type = GetZipFileTreeType(filename);
+ char *directory = TREE_USERDIR(tree_type);
+
+ if (directory == NULL)
+ {
+ Error(ERR_WARN, "zip file '%s' has invalid content!", filename);
+
+ return FALSE;
+ }
+
+ char *top_dir = ExtractZipFileIntoDirectory(filename, directory, tree_type);
+
+ if (top_dir == NULL)
+ {
+ // error message already issued by "ExtractZipFileIntoDirectory()"
+
+ return FALSE;
+ }
+
+ AddUserTreeSetToTreeInfo(top_dir, tree_type);
+
+ // when adding new level set in main menu, select it as current level set
+ if (tree_type == TREE_TYPE_LEVEL_DIR &&
+ game_status == GAME_MODE_MAIN &&
+ !game.request_active)
+ {
+ // change current level set to newly added level set from zip file
+ leveldir_current = getTreeInfoFromIdentifier(leveldir_first, top_dir);