fixed file naming thingy

bdfr/resource.py

@@ -24,10 +24,16 @@ class Resource:
         self.content: Optional[bytes] = None
         self.url = url
         self.hash: Optional[_hashlib.HASH] = None
+        
+        # Log the original extension before normalization
+        if extension:
+            logger.debug(f"Resource constructor received extension: '{extension}' for URL: {url}")
+        
         self.extension = self._normalize_extension(extension)
         self.download_function = download_function
         if not self.extension:
             self.extension = self._determine_extension()
+            logger.debug(f"Extension determined from URL: '{self.extension}' for URL: {url}")
 
     @staticmethod
     def retry_download(url: str) -> Callable:
@@ -121,8 +127,15 @@ class Resource:
         """Normalize extension to lowercase for consistency"""
         if not extension:
             return None
+        
+        original = extension
+        # Ensure extension starts with a dot
+        if not extension.startswith('.'):
+            extension = '.' + extension
+        
         normalized = extension.lower()
-        logger.debug(f"Normalized extension '{extension}' to '{normalized}'")
+        if original != normalized:
+            logger.info(f"Extension normalization: '{original}' -> '{normalized}' for URL: {self.url if hasattr(self, 'url') else 'unknown'}")
         return normalized
 
     @staticmethod