add controllers, servoices

app/Services/PhoneFormatterService.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Services;
+
+class PhoneFormatterService
+{
+    public function formatPhoneNumber(string $number): ?string
+    {
+        $digits = preg_replace('/\D/', '', $number);
+
+        if (strlen($digits) === 10) {
+            return sprintf(
+                '%s-%s-%s',
+                substr($digits, 0, 3),
+                substr($digits, 3, 3),
+                substr($digits, 6)
+            );
+        }
+
+        return null;
+    }
+}