fix: (passenger): block payment initiation too close to the booking deadline

apps/edr-passenger-api/src/common/utils/payment-deadline.utils.ts

@@ -13,11 +13,17 @@ export const MAX_PAYMENT_HOURS = 2;
 export const CUTOFF_MINUTES = 30;
 
 /**
- * payment_deadline = MIN(booking_time + MAX_PAYMENT_HOURS, segment_departure - checkinMinutes)
- *
- * checkinMinutes defaults to CUTOFF_MINUTES but callers should pass the route-level
- * checkinMinutesBefore so that each route's own window is respected.
+ * How long a passenger is given to finish one provider payment session, once opened.
+ * 5 minutes of actual paying (redirect → PIN/OTP → provider callback) + 1 minute of slack.
  */
+export const PAYMENT_SESSION_MINUTES = 6;
+
+
+export const MIN_PAYMENT_WINDOW_MINUTES = 7;
+
+export const PAYMENT_SETTLE_MARGIN_SECONDS = 60;
+
+
 export function computePaymentDeadline(
   createdAt: Date,
   departureAt: Date,
@@ -27,3 +33,19 @@ export function computePaymentDeadline(
   const cutoffDeadline = new Date(departureAt.getTime() - checkinMinutes * 60 * 1000);
   return maxDeadline < cutoffDeadline ? maxDeadline : cutoffDeadline;
 }
+
+
+export function canOpenPaymentSession(
+  paymentDeadline: Date,
+  now: Date = new Date(),
+): boolean {
+  return paymentDeadline.getTime() - now.getTime() >= MIN_PAYMENT_WINDOW_MINUTES * 60 * 1000;
+}
+
+export function computePaymentSessionExpiry(
+  paymentDeadline: Date,
+  now: Date = new Date(),
+): Date {
+  const sessionEnd = new Date(now.getTime() + PAYMENT_SESSION_MINUTES * 60 * 1000);
+  return sessionEnd < paymentDeadline ? sessionEnd : paymentDeadline;
+}