refactor: split buspro ApiClient into domain clients

src/BusProNet/MessageType.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\BusProNet;
+
+/**
+ * The `typ` of BusPro's `<satz>`: the command on a request, the kind of answer on a response.
+ */
+enum MessageType: string
+{
+    // Only ever a response: BusPro's refusal or remark, whatever was asked.
+    case Notification = 'HINWEIS';
+    case CustomerData = 'KUNDENKONTO';
+    case Countries = 'STAMMLAENDER';
+    case MutableData = 'MOEGLICHEAENDERUNGEN';
+    case Availability = 'VERFUEGBARKEIT';
+    case AvailabilityExtended = 'VERFUEGBARKEIT2';
+    case AvailabilityHotel = 'VERFUEGBARKEITHOTEL';
+    case BookingUpdate = 'BUCHUNGAENDERUNG';
+    case Booking = 'BUCHUNG';
+    case Products = 'PRODUKTE';
+    case ProductData = 'PRODUKTDATEN';
+    case Agencies = 'AGENTUREN';
+    case PurchaseVoucher = 'GUTSCHEINPRUEFUNGEINLOESUNG';
+    case PromoVoucher = 'AKTIONSGUTSCHEIN';
+    // Selling Kaufgutscheine. Not to be confused with PurchaseVoucher, which redeems one in a booking.
+    case VoucherTemplates = 'GUTSCHEINVORLAGEN';
+    case VoucherPaymentMethods = 'GUTSCHEINZAHLUNGSARTEN';
+    case VoucherPreview = 'GUTSCHEINVORSCHAU';
+    case VoucherSale = 'GUTSCHEINBUCHUNG';
+}