wip: age based filtering of options

src/Form/Service/Condition/DateOfBirthProvidedCondition.php

@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Form\Service\Condition;
+
+use App\Form\Model\BookingDtoInterface;
+use App\Form\Service\Contract\FieldConditionInterface;
+
+/**
+ * Condition that evaluates whether a participant has provided their date of birth.
+ *
+ * This condition checks if a participant has a valid date of birth set, which is
+ * required for evaluating age-based service constraints and showing age-dependent
+ * form fields. When no birth date is provided, age-restricted fields should be
+ * hidden until this prerequisite is met.
+ *
+ * The condition is commonly used to control field visibility, ensuring that
+ * age-dependent services and options are only displayed when the participant's
+ * age can be calculated.
+ */
+class DateOfBirthProvidedCondition implements FieldConditionInterface
+{
+    /**
+     * Evaluates if the participant has provided their date of birth.
+     *
+     * Checks if the participant exists and has a non-null dateOfBirth property.
+     * This is a prerequisite for showing age-dependent form fields and services.
+     *
+     * @param BookingDtoInterface  $bookingDto       The current booking data
+     * @param int                  $participantIndex The index of the participant being evaluated
+     * @param array<string, mixed> $formData         Current form data (unused for this condition)
+     *
+     * @return bool True if the participant has provided their date of birth, false otherwise
+     */
+    public function evaluate(BookingDtoInterface $bookingDto, int $participantIndex, array $formData): bool
+    {
+        $participant = $bookingDto->getParticipant($participantIndex);
+
+        return null !== $participant && null !== $participant->dateOfBirth;
+    }
+
+    /**
+     * Returns field names that this condition depends on.
+     *
+     * The date of birth condition depends on the participant's dateOfBirth field.
+     * When this field changes, any conditions based on birth date availability
+     * should be re-evaluated.
+     *
+     * @return string[] Array containing 'dateOfBirth' field name
+     */
+    public function getDependentFields(): array
+    {
+        return ['dateOfBirth'];
+    }
+
+    /**
+     * Returns a human-readable description of this condition.
+     *
+     * Provides a clear description of what this condition checks for,
+     * useful for debugging and understanding field state logic.
+     *
+     * @return string Description of the date of birth requirement
+     */
+    public function getDescription(): string
+    {
+        return 'Participant must provide their date of birth';
+    }
+}