restructured the read in / sort order.

app.py

@@ -27,7 +27,20 @@ import gpxpy
 # === Helper Functions ===
 def list_gpx_files():
     folder = './gpx_files'
-    return [{'label': f, 'value': os.path.join(folder, f)} for f in os.listdir(folder) if f.endswith('.gpx')]
+    #return [{'label': f, 'value': os.path.join(folder, f)} for f in os.listdir(folder) if f.endswith('.gpx')]
+    files = [f for f in os.listdir(folder) if f.endswith('.gpx')]
+
+    # Extract date from the start of the filename and sort descending
+    def extract_date(filename):
+        try:
+            return datetime.datetime.strptime(filename[:10], '%Y-%m-%d')
+        except ValueError:
+            return datetime.datetime.min  # Put files without a valid date at the end
+
+    files.sort(key=extract_date, reverse=True)
+
+    return [{'label': f, 'value': os.path.join(folder, f)} for f in files]
+
 
 
 def haversine(lon1, lat1, lon2, lat2):