feat: make email optional for under-16 participants except applicant

src/Form/Service/Condition/RequiresOwnEmailCondition.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Form\Service\Condition;
+
+use App\Form\Model\BookingDto;
+use App\Form\Service\Contract\FieldConditionInterface;
+
+/**
+ * Condition that mirrors BookingDto::requiresParticipantEmail() into the field state layer.
+ *
+ * It deliberately holds no logic of its own, so the mandatory marker rendered next to the field
+ * is derived from the same method that describes what validation enforces, rather than from a
+ * second, independently maintained composition of age and applicant conditions.
+ */
+class RequiresOwnEmailCondition implements FieldConditionInterface
+{
+    /**
+     * Evaluates whether the participant has to supply an email address of their own.
+     *
+     * @param BookingDto           $bookingDto       The current booking data (create or edit)
+     * @param int                  $participantIndex The index of the participant being evaluated
+     * @param array<string, mixed> $formData         Current form data (unused)
+     *
+     * @return bool True if the participant needs their own email address
+     */
+    public function evaluate(BookingDto $bookingDto, int $participantIndex, array $formData): bool
+    {
+        return $bookingDto->requiresParticipantEmail($participantIndex);
+    }
+
+    /**
+     * The rule reads the date of birth, so the state has to be recalculated when it changes.
+     *
+     * @return string[] Array containing 'dateOfBirth'
+     */
+    public function getDependentFields(): array
+    {
+        return ['dateOfBirth'];
+    }
+
+    public function getDescription(): string
+    {
+        return 'Checks if the participant needs an email address of their own';
+    }
+}