Sync active room stays when booking expected dates change

docs/API_REFERENCE.txt

@@ -1361,6 +1361,7 @@ ROOM STAYS + CARDS APIS
   What it does:
 
   - Returns active stays with booking and guest details.
+  - expectedCheckoutAt is resolved per active stay (room_stay.planned_checkout_at), with booking expected checkout as fallback.
   - Includes per-stay nightlyRate (nullable when rate was not set on room stay).
   - AGENT-only users are blocked.
 
@@ -1822,7 +1823,11 @@ BOOKING APIS
   What it does:
 
   - Updates planned dates on booking (expectedCheckInAt, expectedCheckOutAt), not actual checkout.
-  - Updates booking-level expected dates only; does not auto-change room_stay checkout timestamps.
+  - Updates booking-level expected dates.
+  - After validation, auto-syncs linked active room stays (checked-out stays are not modified):
+      - OPEN booking: active stay fromAt is synced to expectedCheckInAt (when provided).
+      - OPEN/CHECKED_IN booking: active stay planned checkout is synced to expectedCheckOutAt (when provided).
+  - Does not auto-close room stays and does not overwrite actual room_stay.to_at timestamps.
   - For OPEN bookings: can update both expected check-in and expected check-out.
   - For OPEN bookings with linked room stays: each stay start/end must remain inside expected booking window.
   - For CHECKED_IN: can update only expectedCheckOutAt (check-in change is blocked).

src/main/kotlin/com/android/trisolarisserver/controller/booking/BookingFlow.kt

@@ -511,6 +511,7 @@ class BookingFlow(
                 room = room,
                 fromAt = checkInAt,
                 toAt = null,
+                plannedCheckoutAt = booking.expectedCheckoutAt,
                 rateSource = parseRateSource(stay.rateSource),
                 nightlyRate = stay.nightlyRate,
                 ratePlanCode = stay.ratePlanCode,
@@ -579,6 +580,7 @@ class BookingFlow(
             throw ResponseStatusException(HttpStatus.BAD_REQUEST, "Invalid date range")
         }
         validateRoomStayBoundsForExpectedDatesUpdate(booking, expectedIn, expectedOut)
+        syncActiveRoomStaysWithBookingExpectedDates(booking, expectedIn, expectedOut)
 
         booking.updatedAt = OffsetDateTime.now()
         bookingRepo.save(booking)
@@ -637,6 +639,32 @@ class BookingFlow(
         }
     }
 
+    private fun syncActiveRoomStaysWithBookingExpectedDates(
+        booking: com.android.trisolarisserver.models.booking.Booking,
+        expectedIn: OffsetDateTime?,
+        expectedOut: OffsetDateTime?
+    ) {
+        val bookingId = booking.id ?: return
+        if (expectedIn == null && expectedOut == null) return
+        val activeStays = roomStayRepo.findActiveByBookingId(bookingId)
+        if (activeStays.isEmpty()) return
+
+        var changed = false
+        activeStays.forEach { stay ->
+            if (booking.status == BookingStatus.OPEN && expectedIn != null && stay.fromAt != expectedIn) {
+                stay.fromAt = expectedIn
+                changed = true
+            }
+            if (expectedOut != null && stay.plannedCheckoutAt != expectedOut) {
+                stay.plannedCheckoutAt = expectedOut
+                changed = true
+            }
+        }
+        if (changed) {
+            roomStayRepo.saveAll(activeStays)
+        }
+    }
+
     @PostMapping("/{bookingId}/billing-policy")
     @ResponseStatus(HttpStatus.NO_CONTENT)
     @Transactional

src/main/kotlin/com/android/trisolarisserver/controller/room/RoomStays.kt

@@ -69,7 +69,7 @@ class RoomStays(
                 roomTypeName = roomType.name,
                 fromAt = stay.fromAt.toString(),
                 checkinAt = booking.checkinAt?.toString(),
-                expectedCheckoutAt = booking.expectedCheckoutAt?.toString(),
+                expectedCheckoutAt = (stay.plannedCheckoutAt ?: booking.expectedCheckoutAt)?.toString(),
                 nightlyRate = stay.nightlyRate
             )
         }

src/main/kotlin/com/android/trisolarisserver/models/room/RoomStay.kt

@@ -33,6 +33,9 @@ class RoomStay(
     @Column(name = "to_at", columnDefinition = "timestamptz")
     var toAt: OffsetDateTime? = null,   // null = active
 
+    @Column(name = "planned_checkout_at", columnDefinition = "timestamptz")
+    var plannedCheckoutAt: OffsetDateTime? = null,
+
     @Column(name = "is_voided", nullable = false)
     var isVoided: Boolean = false,
 

src/main/kotlin/com/android/trisolarisserver/repo/room/RoomStayRepo.kt

@@ -48,7 +48,7 @@ interface RoomStayRepo : JpaRepository<RoomStay, UUID> {
     @Query("""
         select rs.room.id as roomId,
                rs.fromAt as fromAt,
-               b.expectedCheckoutAt as expectedCheckoutAt
+               coalesce(rs.plannedCheckoutAt, b.expectedCheckoutAt) as expectedCheckoutAt
         from RoomStay rs
         join rs.booking b
         where rs.property.id = :propertyId