feat: refactor to cards

src/Controller/Booking/Traits/ParticipantValidationTrait.php

@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Controller\Booking\Traits;
+
+/**
+ * Provides participant validation error extraction for card-based booking flows.
+ *
+ * Shared between CreateStep2Controller and EditController to identify which
+ * participants have validation errors that should be displayed on their cards.
+ */
+trait ParticipantValidationTrait
+{
+    /**
+     * Extracts participant indices that have validation errors.
+     *
+     * Parses form errors to identify which participants have validation issues.
+     * Returns an array of participant indices (e.g., [0, 2, 5]).
+     *
+     * @return array<int> Array of participant indices with errors
+     */
+    private function extractParticipantErrorIndices($form): array
+    {
+        $errorIndices = [];
+        $errors = $form->getErrors(true); // Get all errors recursively
+
+        foreach ($errors as $error) {
+            $propertyPath = $error->getCause()?->getPropertyPath();
+            if (null === $propertyPath) {
+                continue;
+            }
+
+            // Property paths look like "participants[0].firstName" or "participants[1].email"
+            if (preg_match('/participants\[(\d+)]/', $propertyPath, $matches)) {
+                $index = (int) $matches[1];
+                $errorIndices[$index] = true; // Use array key to avoid duplicates
+            }
+        }
+
+        return array_keys($errorIndices);
+    }
+}