Prefill date selectors on leadership page with earliest/latest dates

app/routes/leaderboard.py

@@ -1,6 +1,8 @@
 from flask import Blueprint, render_template
 from app.auth import login_required
-from app.db import query
+from app.db import query, query_one
+from app import SYDNEY_TZ
+from datetime import timezone
 
 bp = Blueprint("leaderboard", __name__)
 
@@ -54,4 +56,25 @@ def index():
     # Sort by % lost (descending)
     ranked.sort(key=lambda x: x["pct_lost"], reverse=True)
 
-    return render_template("leaderboard.html", ranked=ranked)
+    # Get earliest and latest check-in dates for date pickers
+    date_range = query_one("""
+        SELECT
+            MIN(c.checked_in_at) AS earliest,
+            MAX(c.checked_in_at) AS latest
+        FROM checkins c
+        JOIN users u ON u.id = c.user_id
+        WHERE u.is_private = FALSE
+    """)
+    earliest = ""
+    latest = ""
+    if date_range and date_range["earliest"]:
+        e = date_range["earliest"]
+        l = date_range["latest"]
+        if e.tzinfo is None:
+            e = e.replace(tzinfo=timezone.utc)
+        if l.tzinfo is None:
+            l = l.replace(tzinfo=timezone.utc)
+        earliest = e.astimezone(SYDNEY_TZ).strftime("%Y-%m-%d")
+        latest = l.astimezone(SYDNEY_TZ).strftime("%Y-%m-%d")
+
+    return render_template("leaderboard.html", ranked=ranked, earliest=earliest, latest=latest)