Add week and year parameters to weekends page.

Fixes #190

web_view.py

@@ -231,14 +231,29 @@ async def gaps_page() -> str:
 
 @app.route("/weekends")
 async def weekends() -> str:
-    """List of available weekends using an optional date parameter."""
+    """List of available weekends using an optional date, week, or year parameter."""
     today = datetime.now().date()
     date_str = flask.request.args.get("date")
+    week_str = flask.request.args.get("week")
+    year_str = flask.request.args.get("year")
+
     if date_str:
         try:
             start = datetime.strptime(date_str, "%Y-%m-%d").date()
         except ValueError:
             return flask.abort(400, description="Invalid date format. Use YYYY-MM-DD.")
+    elif week_str:
+        try:
+            week = int(week_str)
+            year = int(year_str) if year_str else today.year
+            if week < 1 or week > 53:
+                return flask.abort(400, description="Week number must be between 1 and 53.")
+            # Calculate the date of the first day of the given week
+            jan_1 = date(year, 1, 1)
+            week_1_start = jan_1 - timedelta(days=jan_1.weekday())
+            start = week_1_start + timedelta(weeks=week - 1)
+        except ValueError:
+            return flask.abort(400, description="Invalid week or year format. Use integers.")
     else:
         start = date(today.year, 1, 1)