(add TicketPurchasingService)

...only to be deleted in the very next commit! 😈

app/TicketPurchasingService.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace App;
+
+use App\Order;
+use App\Billing\PaymentGateway;
+
+class TicketPurchasingService
+{
+    private $paymentGateway;
+
+    public function __construct(PaymentGateway $paymentGateway)
+    {
+        $this->paymentGateway = $paymentGateway;
+    }
+
+    public function purchaseTickets($concert, $ticketQuantity, $email, $paymentToken)
+    {
+        $reservation = $concert->reserveTickets($ticketQuantity, $email);
+
+        $this->paymentGateway->charge($reservation->totalCost(), $paymentToken);
+
+        return Order::forTickets($reservation->tickets(), $reservation->email(), $reservation->totalCost());
+    }
+}