feat: Rechnungsversand als signierte E-Rechnung mit Sammel-ZIP-Download, Abbruch bei fehlgeschlagener Validierung (HTTP 422)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/src/main/java/de/assecutor/votianlt/pages/view/AdminCreateInvoicesView.java

@@ -552,10 +552,42 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
     }
 
     /**
-     * Sends each invoice as PDF attachment to the respective customer's email
-     * address and reports how many mails were (not) sent.
+     * Sends the invoices as signed ZUGFeRD e-invoice (ZIP) to the respective
+     * customers. First all signed ZIPs are created and cached; only when every
+     * ZIP could be created and passed the validation the mails are sent.
+     * Afterwards a combined ZIP containing all individual invoice ZIPs is
+     * offered as browser download.
      */
     private void sendInvoices(List<InvoicePreview> previews) {
+        // Phase 1: create and cache the signed ZIP of every invoice; abort
+        // without sending anything if a single one fails
+        Map<InvoicePreview, PdfToolService.SignedInvoice> signedZips = new LinkedHashMap<>();
+        for (InvoicePreview preview : previews) {
+            try {
+                signedZips.put(preview, pdfToolService.signInvoice(preview.pdf(), buildZugferdMetadata(preview)));
+            } catch (Exception ex) {
+                log.error("Error creating ZUGFeRD e-invoice {} for batch send: {}", preview.invoiceNumber(),
+                        ex.getMessage(), ex);
+                Notification
+                        .show(getTranslation("admincreateinvoices.notification.zugferd.batcherror",
+                                preview.invoiceNumber(), ex.getMessage()), 7000, Notification.Position.BOTTOM_CENTER)
+                        .addThemeVariants(NotificationVariant.LUMO_ERROR);
+                return;
+            }
+        }
+        // Invoices failing the Mustang validation stop the whole batch: no
+        // mail is sent as long as a single invoice is invalid
+        String invalidNumbers = signedZips.entrySet().stream().filter(entry -> !entry.getValue().valid())
+                .map(entry -> entry.getKey().invoiceNumber()).collect(java.util.stream.Collectors.joining(", "));
+        if (!invalidNumbers.isEmpty()) {
+            log.warn("Invoice batch send aborted, validation failed for: {}", invalidNumbers);
+            Notification
+                    .show(getTranslation("admincreateinvoices.notification.zugferd.invalidsend", invalidNumbers),
+                            7000, Notification.Position.BOTTOM_CENTER)
+                    .addThemeVariants(NotificationVariant.LUMO_ERROR);
+            return;
+        }
+
         String issuerName = "";
         try {
             issuerName = safe(systemCompanyProfileService.createSystemInvoiceData().getCompanyName());
@@ -564,9 +596,12 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
         }
         String monthLabel = billingMonth.format(DateTimeFormatter.ofPattern("LLLL yyyy", getLocale()));
 
+        // Phase 2: all ZIPs exist, send one mail per invoice with its ZIP
         int sent = 0;
         int failed = 0;
-        for (InvoicePreview preview : previews) {
+        for (Map.Entry<InvoicePreview, PdfToolService.SignedInvoice> entry : signedZips.entrySet()) {
+            InvoicePreview preview = entry.getKey();
+            PdfToolService.SignedInvoice signed = entry.getValue();
             String email = preview.info().user().getEmail();
             if (email == null || email.isBlank()) {
                 log.warn("Customer {} has no email address, invoice {} not sent",
@@ -579,7 +614,7 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
                         getTranslation("admincreateinvoices.mail.subject", preview.invoiceNumber()),
                         getTranslation("admincreateinvoices.mail.body", preview.invoiceNumber(), monthLabel,
                                 issuerName),
-                        preview.pdf(), preview.invoiceNumber() + ".pdf");
+                        signed.zip(), signed.fileName());
                 recordDispatch(preview, email);
                 sent++;
             } catch (Exception ex) {
@@ -587,6 +622,22 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
                 failed++;
             }
         }
+
+        // Phase 3: bundle all individual invoice ZIPs and offer the download
+        if (signedZips.size() > 1) {
+            try {
+                String archiveName = "rechnungen-" + billingMonth.format(DateTimeFormatter.ofPattern("yyyy-MM"))
+                        + "-zugferd.zip";
+                triggerZipDownload(buildCombinedZip(signedZips.values()), archiveName);
+            } catch (Exception ex) {
+                log.error("Error creating combined invoice ZIP: {}", ex.getMessage(), ex);
+                Notification
+                        .show(getTranslation("admincreateinvoices.notification.zip.combined.error", ex.getMessage()),
+                                7000, Notification.Position.BOTTOM_CENTER)
+                        .addThemeVariants(NotificationVariant.LUMO_ERROR);
+            }
+        }
+
         if (sent > 0) {
             grid.deselectAll();
             grid.setItems(loadBillingInfos());
@@ -748,11 +799,7 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
         try {
             PdfToolService.SignedInvoice signed = pdfToolService.signInvoice(preview.pdf(),
                     buildZugferdMetadata(preview));
-            String base64Zip = Base64.getEncoder().encodeToString(signed.zip());
-            getElement().executeJs("const link = document.createElement('a');"
-                    + "link.href = 'data:application/zip;base64," + base64Zip + "';" + "link.download = '"
-                    + signed.fileName().replace("'", "") + "';"
-                    + "document.body.appendChild(link); link.click(); document.body.removeChild(link);");
+            triggerZipDownload(signed.zip(), signed.fileName());
             if (signed.valid()) {
                 Notification
                         .show(getTranslation("admincreateinvoices.notification.zugferd.created",
@@ -773,6 +820,32 @@ public class AdminCreateInvoicesView extends Main implements HasDynamicTitle {
         }
     }
 
+    /**
+     * Packs the individual invoice ZIPs into one combined ZIP so all sent
+     * e-invoices can be archived with a single download.
+     */
+    private byte[] buildCombinedZip(java.util.Collection<PdfToolService.SignedInvoice> signedInvoices)
+            throws java.io.IOException {
+        java.io.ByteArrayOutputStream buffer = new java.io.ByteArrayOutputStream();
+        try (java.util.zip.ZipOutputStream zipStream = new java.util.zip.ZipOutputStream(buffer)) {
+            for (PdfToolService.SignedInvoice signed : signedInvoices) {
+                zipStream.putNextEntry(new java.util.zip.ZipEntry(signed.fileName()));
+                zipStream.write(signed.zip());
+                zipStream.closeEntry();
+            }
+        }
+        return buffer.toByteArray();
+    }
+
+    /** Offers the given ZIP bytes as browser download. */
+    private void triggerZipDownload(byte[] zip, String fileName) {
+        String base64Zip = Base64.getEncoder().encodeToString(zip);
+        getElement().executeJs("const link = document.createElement('a');"
+                + "link.href = 'data:application/zip;base64," + base64Zip + "';" + "link.download = '"
+                + fileName.replace("'", "") + "';"
+                + "document.body.appendChild(link); link.click(); document.body.removeChild(link);");
+    }
+
     /**
      * Builds the EN16931 metadata for the PDF Tool from the billing data: the
      * system operator as sender, the customer as recipient and the billed

backend/src/main/java/de/assecutor/votianlt/service/PdfToolService.java

@@ -65,7 +65,10 @@ public class PdfToolService {
     /**
      * Converts the given invoice PDF into a ZUGFeRD e-invoice. Returns the ZIP
      * provided by the PDF Tool; throws with the tool's error message if the
-     * conversion is rejected (e.g. incomplete metadata).
+     * conversion is rejected (e.g. incomplete metadata). A failed Mustang
+     * validation is reported by the tool as HTTP 422 but still carries the ZIP
+     * (including the validation report) in the body; it is returned as a
+     * {@link SignedInvoice} with {@code valid=false} instead of throwing.
      */
     public SignedInvoice signInvoice(byte[] pdfBytes, InvoiceMetadata metadata) throws Exception {
         String metadataJson = objectMapper.writeValueAsString(metadata);
@@ -79,23 +82,30 @@ public class PdfToolService {
         }, MediaType.APPLICATION_PDF);
         body.part("metadata", metadataJson, MediaType.APPLICATION_JSON);
 
-        ResponseEntity<byte[]> response;
         try {
-            response = restClient.post().uri("/api/invoices/sign").contentType(MediaType.MULTIPART_FORM_DATA)
-                    .body(body.build()).retrieve().toEntity(byte[].class);
+            ResponseEntity<byte[]> response = restClient.post().uri("/api/invoices/sign")
+                    .contentType(MediaType.MULTIPART_FORM_DATA).body(body.build()).retrieve()
+                    .toEntity(byte[].class);
+            return toSignedInvoice(response.getBody(), response.getHeaders(), metadata);
         } catch (RestClientResponseException ex) {
+            if (ex.getStatusCode().value() == 422 && ex.getResponseBodyAsByteArray().length > 0) {
+                return toSignedInvoice(ex.getResponseBodyAsByteArray(), ex.getResponseHeaders(), metadata);
+            }
             throw new IllegalStateException(extractErrorMessage(ex), ex);
         }
+    }
 
-        byte[] zip = response.getBody();
+    /** Builds the result from the response ZIP, file name and validation header. */
+    private SignedInvoice toSignedInvoice(byte[] zip, org.springframework.http.HttpHeaders headers,
+            InvoiceMetadata metadata) {
         if (zip == null || zip.length == 0) {
             throw new IllegalStateException("PDF Tool returned an empty response");
         }
-        String fileName = response.getHeaders().getContentDisposition().getFilename();
+        String fileName = headers != null ? headers.getContentDisposition().getFilename() : null;
         if (fileName == null || fileName.isBlank()) {
             fileName = metadata.invoiceNumber() + "-zugferd.zip";
         }
-        boolean valid = Boolean.parseBoolean(response.getHeaders().getFirst(VALIDATION_HEADER));
+        boolean valid = headers != null && Boolean.parseBoolean(headers.getFirst(VALIDATION_HEADER));
         return new SignedInvoice(zip, fileName, valid);
     }
 

backend/src/main/resources/messages_de.properties

@@ -1153,3 +1153,6 @@ admincreateinvoices.notification.zugferd.created=E-Rechnung {0} erstellt
 admincreateinvoices.notification.zugferd.invalid=E-Rechnung erstellt, aber die Validierung ist fehlgeschlagen. Details im Prüfbericht in der ZIP-Datei.
 admincreateinvoices.notification.zugferd.error=Fehler beim Erstellen der E-Rechnung: {0}
 admincreateinvoices.notification.zugferd.nopositions=Keine abrechenbaren Positionen für die E-Rechnung vorhanden
+admincreateinvoices.notification.zugferd.batcherror=E-Rechnung {0} konnte nicht erstellt werden, es wurden keine Rechnungen versendet: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Validierung fehlgeschlagen für: {0}. Es wurden keine Rechnungen versendet.
+admincreateinvoices.notification.zip.combined.error=Fehler beim Erstellen der Sammel-ZIP-Datei: {0}

backend/src/main/resources/messages_ee.properties

@@ -983,3 +983,6 @@ admincreateinvoices.notification.zugferd.created=E-arve {0} loodud
 admincreateinvoices.notification.zugferd.invalid=E-arve on loodud, kuid valideerimine ebaõnnestus. Üksikasjad on ZIP-failis olevas valideerimisaruandes.
 admincreateinvoices.notification.zugferd.error=Viga e-arve loomisel: {0}
 admincreateinvoices.notification.zugferd.nopositions=E-arve jaoks puuduvad arveldatavad positsioonid
+admincreateinvoices.notification.zugferd.batcherror=E-arvet {0} ei õnnestunud luua, ühtegi arvet ei saadetud: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Valideerimine ebaõnnestus: {0}. Ühtegi arvet ei saadetud.
+admincreateinvoices.notification.zip.combined.error=Viga koond-ZIP-faili loomisel: {0}

backend/src/main/resources/messages_en.properties

@@ -1153,3 +1153,6 @@ admincreateinvoices.notification.zugferd.created=E-invoice {0} created
 admincreateinvoices.notification.zugferd.invalid=E-invoice created, but validation failed. See the validation report in the ZIP file.
 admincreateinvoices.notification.zugferd.error=Error creating the e-invoice: {0}
 admincreateinvoices.notification.zugferd.nopositions=No billable positions available for the e-invoice
+admincreateinvoices.notification.zugferd.batcherror=E-invoice {0} could not be created, no invoices were sent: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Validation failed for: {0}. No invoices were sent.
+admincreateinvoices.notification.zip.combined.error=Error creating the combined ZIP file: {0}

backend/src/main/resources/messages_es.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created=Factura electrónica {0} creada
 admincreateinvoices.notification.zugferd.invalid=Factura electrónica creada, pero la validación ha fallado. Consulte el informe de validación en el archivo ZIP.
 admincreateinvoices.notification.zugferd.error=Error al crear la factura electrónica: {0}
 admincreateinvoices.notification.zugferd.nopositions=No hay posiciones facturables disponibles para la factura electrónica
+admincreateinvoices.notification.zugferd.batcherror=No se pudo crear la factura electrónica {0}, no se envió ninguna factura: {1}
+admincreateinvoices.notification.zugferd.invalidsend=La validación falló para: {0}. No se envió ninguna factura.
+admincreateinvoices.notification.zip.combined.error=Error al crear el archivo ZIP combinado: {0}

backend/src/main/resources/messages_fr.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created=Facture électronique {0} cré
 admincreateinvoices.notification.zugferd.invalid=Facture électronique créée, mais la validation a échoué. Détails dans le rapport de validation du fichier ZIP.
 admincreateinvoices.notification.zugferd.error=Erreur lors de la création de la facture électronique : {0}
 admincreateinvoices.notification.zugferd.nopositions=Aucune position facturable disponible pour la facture électronique
+admincreateinvoices.notification.zugferd.batcherror=La facture électronique {0} n''a pas pu être créée, aucune facture n''a été envoyée : {1}
+admincreateinvoices.notification.zugferd.invalidsend=La validation a échoué pour : {0}. Aucune facture n''a été envoyée.
+admincreateinvoices.notification.zip.combined.error=Erreur lors de la création du fichier ZIP combiné : {0}

backend/src/main/resources/messages_lt.properties

@@ -1086,3 +1086,6 @@ admincreateinvoices.notification.zugferd.created=E. sąskaita {0} sukurta
 admincreateinvoices.notification.zugferd.invalid=E. sąskaita sukurta, tačiau patikra nepavyko. Išsami informacija patikros ataskaitoje ZIP faile.
 admincreateinvoices.notification.zugferd.error=Klaida kuriant e. sąskaitą: {0}
 admincreateinvoices.notification.zugferd.nopositions=E. sąskaitai nėra apmokestinamų pozicijų
+admincreateinvoices.notification.zugferd.batcherror=Nepavyko sukurti e. sąskaitos {0}, sąskaitos nebuvo išsiųstos: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Patikrinimas nepavyko: {0}. Sąskaitos nebuvo išsiųstos.
+admincreateinvoices.notification.zip.combined.error=Klaida kuriant bendrą ZIP failą: {0}

backend/src/main/resources/messages_lv.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created=E-rēķins {0} izveidots
 admincreateinvoices.notification.zugferd.invalid=E-rēķins izveidots, bet validācija neizdevās. Detaļas skatiet validācijas atskaitē ZIP failā.
 admincreateinvoices.notification.zugferd.error=Kļūda, veidojot e-rēķinu: {0}
 admincreateinvoices.notification.zugferd.nopositions=E-rēķinam nav pieejamu norēķinu pozīciju
+admincreateinvoices.notification.zugferd.batcherror=Neizdevās izveidot e-rēķinu {0}, rēķini netika nosūtīti: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Validācija neizdevās: {0}. Rēķini netika nosūtīti.
+admincreateinvoices.notification.zip.combined.error=Kļūda, veidojot apvienoto ZIP failu: {0}

backend/src/main/resources/messages_pl.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created=Utworzono e-fakturę {0}
 admincreateinvoices.notification.zugferd.invalid=E-faktura została utworzona, ale walidacja nie powiodła się. Szczegóły w raporcie walidacji w pliku ZIP.
 admincreateinvoices.notification.zugferd.error=Błąd podczas tworzenia e-faktury: {0}
 admincreateinvoices.notification.zugferd.nopositions=Brak pozycji rozliczeniowych dla e-faktury
+admincreateinvoices.notification.zugferd.batcherror=Nie udało się utworzyć e-faktury {0}, żadne faktury nie zostały wysłane: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Walidacja nie powiodła się dla: {0}. Żadne faktury nie zostały wysłane.
+admincreateinvoices.notification.zip.combined.error=Błąd podczas tworzenia zbiorczego pliku ZIP: {0}

backend/src/main/resources/messages_ru.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created=Электронный счёт
 admincreateinvoices.notification.zugferd.invalid=Электронный счёт создан, но проверка не пройдена. Подробности в отчёте о проверке в ZIP-файле.
 admincreateinvoices.notification.zugferd.error=Ошибка при создании электронного счёта: {0}
 admincreateinvoices.notification.zugferd.nopositions=Нет позиций для выставления электронного счёта
+admincreateinvoices.notification.zugferd.batcherror=Не удалось создать электронный счёт {0}, счета не были отправлены: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Проверка не пройдена для: {0}. Счета не были отправлены.
+admincreateinvoices.notification.zip.combined.error=Ошибка при создании общего ZIP-файла: {0}

backend/src/main/resources/messages_tr.properties

@@ -1084,3 +1084,6 @@ admincreateinvoices.notification.zugferd.created={0} numaralı e-fatura oluştur
 admincreateinvoices.notification.zugferd.invalid=E-fatura oluşturuldu ancak doğrulama başarısız oldu. Ayrıntılar ZIP dosyasındaki doğrulama raporunda.
 admincreateinvoices.notification.zugferd.error=E-fatura oluşturulurken hata: {0}
 admincreateinvoices.notification.zugferd.nopositions=E-fatura için faturalandırılabilir pozisyon yok
+admincreateinvoices.notification.zugferd.batcherror=E-fatura {0} oluşturulamadı, hiçbir fatura gönderilmedi: {1}
+admincreateinvoices.notification.zugferd.invalidsend=Doğrulama başarısız oldu: {0}. Hiçbir fatura gönderilmedi.
+admincreateinvoices.notification.zip.combined.error=Toplu ZIP dosyası oluşturulurken hata: {0}