Warn when a marked file is added again

PFERD/diva.py

@@ -1,3 +1,6 @@
+"""
+Utility functions and a scraper/downloader for the KIT DIVA portal.
+"""
 import logging
 import re
 from dataclasses import dataclass

PFERD/organizer.py

@@ -16,8 +16,6 @@ from .utils import prompt_yes_no
 LOGGER = logging.getLogger(__name__)
 PRETTY = PrettyLogger(LOGGER)
 
-# TODO prevent overwriting an already marked file
-
 
 class FileAcceptException(Exception):
     """An exception while accepting a file."""
@@ -47,6 +45,12 @@ class Organizer(Location):
 
         LOGGER.debug("Copying %s to %s", src_absolute, dst_absolute)
 
+        if self._is_marked(dst):
+            LOGGER.warning("File %r was already written!", str(dst_absolute))
+            if not prompt_yes_no(f"Overwrite file?", default=False):
+                PRETTY.ignored_file(dst_absolute, "file was written previously")
+                return
+
         # Destination file is directory
         if dst_absolute.exists() and dst_absolute.is_dir():
             if prompt_yes_no(f"Overwrite folder {dst_absolute} with file?", default=False):
@@ -82,6 +86,13 @@ class Organizer(Location):
         self._known_files.add(absolute_path)
         LOGGER.debug("Tracked %s", absolute_path)
 
+    def _is_marked(self, path: PurePath) -> bool:
+        """
+        Checks whether a file is marked.
+        """
+        absolute_path = self.resolve(path)
+        return absolute_path in self._known_files
+
     def cleanup(self) -> None:
         """Remove all untracked files in the organizer's dir."""
         LOGGER.debug("Deleting all untracked files...")