Maintenance mode activates after current draw completes

- When admin enables maintenance, it's set to 'pending' state
- Maintenance activates automatically after the current draw completes
- Admin can use immediate=true to force immediate activation
- Frontend shows 'Maintenance Scheduled' banner when pending
- Telegram bot warns users but still allows purchases when pending
- Both mode and pending status tracked in system_settings table

back_end/src/controllers/public.ts

@@ -8,6 +8,68 @@ import config from '../config';
 import { JackpotCycle, TicketPurchase, Ticket, Payout } from '../types';
 import { AuthRequest } from '../middleware/auth';
 
+/**
+ * GET /status/maintenance
+ * Public endpoint to check maintenance mode
+ */
+export async function getPublicMaintenanceStatus(req: Request, res: Response) {
+  try {
+    const result = await db.query(
+      `SELECT value FROM system_settings WHERE key = 'maintenance_mode'`
+    );
+    const pendingResult = await db.query(
+      `SELECT value FROM system_settings WHERE key = 'maintenance_pending'`
+    );
+    const messageResult = await db.query(
+      `SELECT value FROM system_settings WHERE key = 'maintenance_message'`
+    );
+
+    const enabled = result.rows[0]?.value === 'true';
+    const pending = pendingResult.rows[0]?.value === 'true';
+    const message = messageResult.rows[0]?.value || 'System is under maintenance. Please try again later.';
+
+    return res.json({
+      version: '1.0',
+      data: {
+        maintenance_mode: enabled,
+        maintenance_pending: pending,
+        message: enabled ? message : (pending ? 'Maintenance will begin after the current draw completes.' : null),
+      },
+    });
+  } catch (error: any) {
+    // If table doesn't exist yet, return not in maintenance
+    return res.json({
+      version: '1.0',
+      data: {
+        maintenance_mode: false,
+        maintenance_pending: false,
+        message: null,
+      },
+    });
+  }
+}
+
+/**
+ * Helper to check if system is in maintenance mode
+ */
+async function isMaintenanceMode(): Promise<{ enabled: boolean; message: string }> {
+  try {
+    const result = await db.query(
+      `SELECT value FROM system_settings WHERE key = 'maintenance_mode'`
+    );
+    const messageResult = await db.query(
+      `SELECT value FROM system_settings WHERE key = 'maintenance_message'`
+    );
+
+    return {
+      enabled: result.rows[0]?.value === 'true',
+      message: messageResult.rows[0]?.value || 'System is under maintenance. Please try again later.',
+    };
+  } catch {
+    return { enabled: false, message: '' };
+  }
+}
+
 const toIsoString = (value: any): string => {
   if (!value) {
     return new Date().toISOString();
@@ -140,6 +202,16 @@ export async function getNextJackpot(req: Request, res: Response) {
  */
 export async function buyTickets(req: AuthRequest, res: Response) {
   try {
+    // Check maintenance mode first
+    const maintenance = await isMaintenanceMode();
+    if (maintenance.enabled) {
+      return res.status(503).json({
+        version: '1.0',
+        error: 'MAINTENANCE_MODE',
+        message: maintenance.message,
+      });
+    }
+
     const { tickets, lightning_address, nostr_pubkey, name, buyer_name } = req.body;
     const userId = req.user?.id || null;
     const authNostrPubkey = req.user?.nostr_pubkey || null;