fix: restore room occupancy lost to case-sensitive xml attribute lookup

src/Controller/Booking/Create/Step2Controller.php

@@ -19,6 +19,9 @@ use App\Service\BookingSessionManager;
 use App\Service\ParticipantDataPrefiller;
 use App\Service\RoomAssigner;
 use App\Service\TravelDataProvider;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\DependencyInjection\Attribute\Autowire;
+use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Attribute\Route;
@@ -38,6 +41,8 @@ class Step2Controller extends AbstractBookingCreateController
         private readonly TravelDataProvider $travelDataService,
         private readonly RoomAssigner $roomAssignmentService,
         private readonly ParticipantDataPrefiller $prepopulationService,
+        #[Autowire(service: 'monolog.logger.bpn')]
+        private readonly LoggerInterface $logger,
     ) {
     }
 
@@ -62,6 +67,10 @@ class Step2Controller extends AbstractBookingCreateController
         $this->travelDataService->enrichWithFreshAvailabilities($bookingCreateDto->travel);
 
         // Ensure correct number of participants first, then prepopulate the applicant if needed.
+        if (null !== $redirect = $this->guardAgainstEmptyParticipantList($bookingCreateDto)) {
+            return $redirect;
+        }
+
         $this->ensureCorrectNumberOfParticipants($bookingCreateDto);
 
         $user = $this->getUser();
@@ -111,6 +120,49 @@ class Step2Controller extends AbstractBookingCreateController
         return $this->render('booking/create/step_2.html.twig', $templateData);
     }
 
+    /**
+     * Rejects a room selection that resolves to no participants at all.
+     *
+     * A selected room with a quantity always yields at least one participant, so a zero count means the
+     * travel data carries no room occupancy. Rendering step 2 anyway would show an empty participant list
+     * that still validates and lets the booking continue to step 3.
+     */
+    private function guardAgainstEmptyParticipantList(BookingDto $bookingCreateDto): ?RedirectResponse
+    {
+        $selectedRooms = $bookingCreateDto->getSelectedRooms();
+
+        if ([] === $selectedRooms) {
+            return null;
+        }
+
+        if (0 < $this->calculateParticipantsCount($bookingCreateDto->roomSelections, $bookingCreateDto->travel)) {
+            return null;
+        }
+
+        $rooms = [];
+        foreach ($selectedRooms as $roomSelection) {
+            $rooms[] = [
+                'roomId' => $roomSelection->id,
+                'quantity' => $roomSelection->quantity,
+                'capacity' => $roomSelection->capacity,
+            ];
+        }
+
+        $this->handleApiError(
+            $this->logger,
+            'Room selection resolves to zero participants; travel data carries no room occupancy.',
+            [
+                'travelId' => $bookingCreateDto->travel->id,
+                'travelCode' => $bookingCreateDto->travel->code,
+                'hotelId' => $bookingCreateDto->hotelId,
+                'rooms' => $rooms,
+            ],
+            'Die Zimmerdaten dieser Reise sind unvollständig. Bitte wähle dein Zimmer erneut oder kontaktiere uns.'
+        );
+
+        return $this->redirectToRoute('app_booking_create_step_1');
+    }
+
     /**
      * Ensures the booking DTO has the expected number of participant objects based on room selections.
      */
@@ -139,7 +191,7 @@ class Step2Controller extends AbstractBookingCreateController
 
         foreach ($roomSelections as $roomSelection) {
             $room = $rooms[$roomSelection->id];
-            $participantsCount += $room->minPax * $roomSelection->quantity;
+            $participantsCount += ($room->minPax ?? 1) * $roomSelection->quantity;
         }
 
         return $participantsCount;