feat: voucher purchase flow

src/BusProNet/Model/VoucherTemplates.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\BusProNet\Model;
+
+/**
+ * The GUTSCHEINVORLAGEN response: the designs on sale plus BusPro's amount bounds.
+ *
+ * The bounds (gutscheinminbetrag/gutscheinmaxbetrag) are not in the vendor documentation,
+ * they were measured on the test system (10 and 5,000 €, both inclusive).
+ */
+final readonly class VoucherTemplates
+{
+    /**
+     * @param list<VoucherTemplate> $templates
+     */
+    public function __construct(
+        public int $minAmount,
+        public int $maxAmount,
+        public array $templates,
+    ) {
+    }
+
+    public function find(int $id): ?VoucherTemplate
+    {
+        foreach ($this->templates as $template) {
+            if ($id === $template->id) {
+                return $template;
+            }
+        }
+
+        return null;
+    }
+}