feat: fold purchase and promo voucher fields into one code field

src/Form/Model/ParticipantEditDto.php

@@ -18,8 +18,6 @@ use function Symfony\Component\String\u;
  * the participant being edited and the full booking context needed for
  * cross-participant validation.
  */
-#[AppAssert\PurchaseVoucher(groups: ['booking_create', 'booking_edit'])]
-#[AppAssert\PromoVoucher(groups: ['booking_create', 'booking_edit'])]
 #[AppAssert\MandatoryAdditionalServicesSelected(groups: ['booking_create', 'booking_edit'])]
 #[AppAssert\SkiPassSelection(groups: ['strict_required'])]
 class ParticipantEditDto
@@ -71,6 +69,29 @@ class ParticipantEditDto
         }
     }
 
+    /**
+     * Reports voucher codes BusPro rejected.
+     *
+     * ParticipantVoucherFieldHandler checks the codes with BusPro while handling the submission and
+     * keeps the outcome on the participant, since the htmx refresh rebuilds the form and drops form
+     * errors. This turns it into a violation so the step cannot be left with a rejected code.
+     */
+    #[Assert\Callback(groups: ['booking_create', 'booking_edit'])]
+    public function validateVoucherCodes(ExecutionContextInterface $context): void
+    {
+        if (null !== $this->participant->voucherCodeError) {
+            $context->buildViolation($this->participant->voucherCodeError)
+                ->atPath('participant.voucherCode')
+                ->addViolation();
+        }
+
+        if (null !== $this->participant->promoVoucherCode && null !== $this->participant->promoVoucherError) {
+            $context->buildViolation($this->participant->promoVoucherError)
+                ->atPath('participant.voucherCode')
+                ->addViolation();
+        }
+    }
+
     /**
      * Validates that non-applicant adult participants have unique email addresses.
      *