Add multi-day capacity engine and booking flow

src/features/api/index.ts

@@ -197,7 +197,12 @@ const handleCheckAvailability = withActiveEvent(async (request, event) => {
   const quantity = Math.max(1, Number.isNaN(parsed) ? 1 : parsed);
   const date = url.searchParams.get("date") || undefined;
   return apiResponse({
-    available: await hasAvailableSpots(event.id, quantity, date),
+    available: await hasAvailableSpots(
+      event.id,
+      quantity,
+      date,
+      event.duration_days,
+    ),
   });
 });
 

src/features/api/webhooks.ts

@@ -28,7 +28,10 @@ import {
   capacityErrorFormatter,
   isRegistrationClosed,
 } from "#routes/format.ts";
-import { ensureAllBookings } from "#routes/public/ticket-payment.ts";
+import {
+  bookingDateFields,
+  ensureAllBookings,
+} from "#routes/public/ticket-payment.ts";
 import { getFromEmailIfConfigured } from "#routes/public/ticket-routes.ts";
 import {
   htmlResponse,
@@ -502,17 +505,21 @@ type CreatedAttendee = Extract<
 
 type CreatedEntry = { attendee: CreatedAttendee; event: EventWithCount };
 
-/** Create the attendee plus per-event bookings atomically. */
+/**
+ * Create the attendee plus per-event bookings atomically.
+ * durationDays is event-scoped and re-read here at finalize time so the
+ * stored range always matches the event's current duration policy.
+ */
 const createAttendeeForSession = async (
   session: ValidatedPaymentSession,
   intent: BookingIntent,
   validatedItems: ValidatedItem[],
 ): Promise<{ ok: true; entries: CreatedEntry[] } | PaymentResult> => {
   const bookings = validatedItems.map(({ item, event }) => ({
-    date: event.event_type === "daily" ? intent.date : null,
     eventId: item.e,
     pricePaid: item.p,
     quantity: item.q,
+    ...bookingDateFields(event, intent.date),
   }));
 
   const result = await createAttendeeAtomic({

src/features/public/ticket-payment.ts

@@ -127,6 +127,19 @@ export const checkAvailability = (
     date,
   );
 
+/**
+ * Shared booking-date fields (date + durationDays). Keeps the payment and
+ * webhook flows aligned: both read duration from the event at insert time.
+ */
+export const bookingDateFields = (
+  event: Pick<TicketEvent["event"], "event_type" | "duration_days">,
+  date: string | null,
+): { date: string | null; durationDays: number } => ({
+  date: event.event_type === "daily" ? date : null,
+  durationDays:
+    event.event_type === "daily" ? Math.max(1, event.duration_days) : 1,
+});
+
 /** Build registration items from events and quantities */
 export const buildRegistrationItems = (
   events: TicketEvent[],
@@ -171,11 +184,16 @@ export const handlePaymentFlow = (
 const buildBookings = (
   selected: EventQty[],
   date: string | null,
-): { eventId: number; quantity: number; date: string | null }[] =>
+): {
+  eventId: number;
+  quantity: number;
+  date: string | null;
+  durationDays: number;
+}[] =>
   selected.map(({ event, qty }) => ({
-    date: event.event_type === "daily" ? date : null,
     eventId: event.id,
     quantity: qty,
+    ...bookingDateFields(event, date),
   }));
 
 /**

src/shared/booking.ts

@@ -49,7 +49,12 @@ export const processBooking = async (
     (customUnitPrice !== undefined && customUnitPrice > 0 && paymentsEnabled);
 
   if (needsPayment) {
-    const available = await hasAvailableSpots(event.id, quantity, date);
+    const available = await hasAvailableSpots(
+      event.id,
+      quantity,
+      date,
+      event.duration_days,
+    );
     if (!available) return { type: "sold_out" };
 
     // Provider is guaranteed to exist when isPaymentsEnabled() is true
@@ -84,7 +89,14 @@ export const processBooking = async (
   // Free event — create attendee atomically
   const result = await createAttendeeAtomic({
     ...contact,
-    bookings: [{ date, eventId: event.id, quantity }],
+    bookings: [
+      {
+        date,
+        durationDays: event.duration_days,
+        eventId: event.id,
+        quantity,
+      },
+    ],
   });
 
   if (!result.success) {