feat: separate extra text for cancellation invoices

locale.xml

@@ -1279,6 +1279,10 @@
             <de><![CDATA[Gutschrift zu Rechnung #[id] vom [date]]]></de>
             <en><![CDATA[Credit Note to invoice #[id] from [date]]]></en>
         </locale>
+        <locale name="message.invoice.cancellationInvoice.additionalInvoiceText" html="true">
+            <de><![CDATA[Storno-Rechnung zu Rechnung #[id] vom [date]]]></de>
+            <en><![CDATA[Cancelletion invoice to invoice #[id] from [date]]]></en>
+        </locale>
         <locale name="message.add.history.sent.to">
             <de><![CDATA[Rechnung wurde versendet an [recipient]]]></de>
             <en><![CDATA[Invoice was sent to [recipient]]]></en>

src/QUI/ERP/Accounting/Invoice/Invoice.php

@@ -533,6 +533,42 @@ public function reversal($reason, $PermissionUser = null)
         );
 
         $CreditNote->setInvoiceType(Handler::TYPE_INVOICE_REVERSAL);
+
+        // Cancellation invoice extra text
+        $localeCode = QUI::getLocale()->getLocalesByLang(
+            QUI::getLocale()->getCurrent()
+        );
+
+        $Formatter = new \IntlDateFormatter(
+            $localeCode[0],
+            \IntlDateFormatter::SHORT,
+            \IntlDateFormatter::NONE
+        );
+
+        $currentDate = $this->getAttribute('date');
+
+        if (!$currentDate) {
+            $currentDate = \time();
+        } else {
+            $currentDate = \strtotime($currentDate);
+        }
+
+        $message = $this->getCustomer()->getLocale()->get(
+            'quiqqer/invoice',
+            'message.invoice.cancellationInvoice.additionalInvoiceText',
+            [
+                'id'   => $this->getId(),
+                'date' => $Formatter->format($currentDate)
+            ]
+        );
+
+        if (empty($message)) {
+            $message = '';
+        }
+
+        // saving copy
+        $CreditNote->setAttribute('additional_invoice_text', $message);
+
         $CreditNote->save(QUI::getUsers()->getSystemUser());
 
         try {
@@ -794,7 +830,7 @@ public function createCreditNote($PermissionUser = null, $globalProcessId = fals
             $currentDate = \strtotime($currentDate);
         }
 
-        $message = QUI::getLocale()->get(
+        $message = $this->getCustomer()->getLocale()->get(
             'quiqqer/invoice',
             'message.invoice.creditNote.additionalInvoiceText',
             [