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

src/BusProNet/XmlParser/AbstractParser.php

@@ -9,15 +9,6 @@ abstract class AbstractParser
 {
     use TypeConversionTrait;
 
-    protected function getIntOrNullAttribute(?string $value): ?int
-    {
-        if (null === $value || '' === $value) {
-            return null;
-        }
-
-        return (int) $value;
-    }
-
     protected function getStringOrNullValue(Crawler $node): ?string
     {
         return 0 < $node->count() ? $node->text() : null;
@@ -64,7 +55,27 @@ abstract class AbstractParser
             return null;
         }
 
-        return $node->attr($attribute);
+        $value = $node->attr($attribute);
+        if (null !== $value) {
+            return $value;
+        }
+
+        // BusPro mixes casing (MinPax in the travel export, minpax in booking
+        // responses) and addXmlContent() makes attr() case-sensitive.
+        foreach ($node->getNode(0)->attributes ?? [] as $candidate) {
+            if (0 === strcasecmp($candidate->name, $attribute)) {
+                return $candidate->value;
+            }
+        }
+
+        return null;
+    }
+
+    protected function getIntAttrOrNullValue(Crawler $node, string $attribute): ?int
+    {
+        $value = $this->getAttrOrNullValue($node, $attribute);
+
+        return null !== $value && '' !== $value ? (int) $value : null;
     }
 
     protected function getRequiredAttrValue(Crawler $node, string $attribute, string $context): string

src/BusProNet/XmlParser/TravelParser.php

@@ -381,8 +381,8 @@ class TravelParser extends AbstractParser
             $room->category = $this->getAttrOrNullValue($roomNode, 'kat');
             $room->boardId = (int) $this->getAttrOrNullValue($roomNode, 'idbuspro_vp');
             $room->label = $this->getAttrOrNullValue($roomNode, 'zimmertext');
-            $room->minPax = (int) $this->getAttrOrNullValue($roomNode, 'minpax');
-            $room->maxPax = (int) $this->getAttrOrNullValue($roomNode, 'maxpax');
+            $room->minPax = $this->getIntAttrOrNullValue($roomNode, 'minpax');
+            $room->maxPax = $this->getIntAttrOrNullValue($roomNode, 'maxpax');
             $room->nights = (int) $this->getAttrOrNullValue($roomNode, 'naechte');
             $roomPrice = $this->getAttrOrNullValue($roomNode, 'preis');
             $room->price = null !== $roomPrice && '' !== $roomPrice

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;

src/Form/RoomSelectType.php

@@ -24,12 +24,17 @@ class RoomSelectType extends AbstractType
                 $data = $event->getData();
                 $form = $event->getForm();
 
+                $choices = ['-' => 0];
+                if (0 < $data->maxQuantity) {
+                    $choices += array_combine(range(1, $data->maxQuantity), range(1, $data->maxQuantity));
+                }
+
                 $form->add('quantity', StepSelectChoiceType::class, [
                     'label' => false,
                     'required' => true,
                     'min_value' => 0,
                     'max_value' => $data->maxQuantity,
-                    'choices' => ['-' => 0] + array_combine(range(1, $data->maxQuantity), range(1, $data->maxQuantity)),
+                    'choices' => $choices,
                 ]);
             });
     }

src/Service/BookingConfigurator.php

@@ -110,7 +110,7 @@ class BookingConfigurator
         $selection->price = $room->price;
         $selection->status = $room->status;
         $selection->maxQuantity = $room->available;
-        $selection->capacity = $room->minPax;
+        $selection->capacity = $room->minPax ?? 1;
         $selection->quantity = $roomsIdsAndQuantities[$room->id] ?? 0;
 
         return $selection;