feat: automatically assign rooms only for unique room type selection

src/Service/RoomAssignmentService.php

@@ -14,6 +14,30 @@ use App\Form\Model\BookingDto;
  */
 class RoomAssignmentService
 {
+    /**
+     * Determines if automatic room assignment should be performed.
+     *
+     * Auto-assignment is only performed when exactly one room type is selected to avoid
+     * UX issues with individual participant forms. With multiple room types, users should
+     * manually select rooms to avoid having to unselect preassigned rooms.
+     *
+     * @param BookingDto $dto The booking DTO containing room selections
+     *
+     * @return bool True if auto-assignment should proceed, false otherwise
+     */
+    public function shouldAutoAssignRooms(BookingDto $dto): bool
+    {
+        $selectedRoomTypeCount = 0;
+
+        foreach ($dto->roomSelections as $roomSelection) {
+            if (null !== $roomSelection->quantity && $roomSelection->quantity > 0) {
+                ++$selectedRoomTypeCount;
+            }
+        }
+
+        return 1 === $selectedRoomTypeCount;
+    }
+
     /**
      * Automatically assigns participants to rooms based on selected room quantities and capacities.
      *
@@ -26,10 +50,17 @@ class RoomAssignmentService
      * - 2x "Doppelzimmer" (capacity 2) = participants 0-1 → room A, participants 2-3 → room A
      * - 1x "3-Bett-Zimmer" (capacity 3) = participants 4-6 → room B
      *
+     * Note: Only performs assignment if shouldAutoAssignRooms() returns true.
+     *
      * @param BookingDto $dto The booking DTO containing room selections and participants
      */
     public function assignParticipantsToRooms(BookingDto $dto): void
     {
+        // Skip auto-assignment if multiple room types selected
+        if (false === $this->shouldAutoAssignRooms($dto)) {
+            return;
+        }
+
         $participantIndex = 0;
         $selectedRooms = $dto->getSelectedRooms();
         $availableRooms = $dto->travel->getAvailableRooms();