Add discounts, fields, and PDF/email support to manual invoices.

application/ManualInvoice/ManualInvoiceModel.php

@@ -4,6 +4,10 @@ class ManualInvoiceModel extends TTCrudBaseModel {
     public int $id;
     public ?string $invoice_number;
     public int $invoice_date;
+    public ?string $leistungszeitraum;
+    public ?string $einleitender_text;
+    public ?string $externe_referenz;
+    public float $gesamtrabatt;
     public int $owner_id;
     public int $billingaddress_id;
     public int $customer_number;
@@ -51,13 +55,13 @@ class ManualInvoiceModel extends TTCrudBaseModel {
         $last = $invoices[0]->invoice_number ?? null;
         $year = date("Y");
 
-        if ($last && preg_match('/^MRN(\d+)-X(\d+)$/', $last, $m)) {
+        if ($last && preg_match('/^RN(\d+)-C(\d+)$/', $last, $m)) {
             $num = ($m[1] == $year) ? $m[2] + 1 : 1;
         } else {
             $num = 1;
         }
 
-        return sprintf("MRN%s-X%06d", $year, $num);
+        return sprintf("RN%s-C%06d", $year, $num);
     }
 
     public function getProperty($name) {