feat: make payment means code (BT-81) dynamically selectable

invoice_logic.py

@@ -58,6 +58,16 @@ VERKAEUFER = {
     "register_id": "HRB 6058 NP",          # BT-30 (Handelsregisternummer, NICHT die USt-ID)
 }
 
+# UN/EDIFACT 4461 Zahlungsmittelcodes (BT-81), Auswahl der fuer B2B/B2G relevanten Codes.
+# "58" bleibt der Standardwert (SEPA-Ueberweisung), da alle bisherigen Rechnungen diesen nutzen.
+PAYMENT_MEANS_CODES = {
+    "58": "SEPA-Überweisung",
+    "30": "Überweisung (allgemein)",
+    "31": "SEPA-Lastschrift",
+    "42": "Einzahlung auf Bankkonto",
+    "48": "Bankkarte (Kredit-/Debitkarte)",
+}
+
 
 def berechne_faelligkeit(invoice_date_str, term_days):
     """Fälligkeitsdatum = Rechnungsdatum + term_days. Gibt 'YYYY-MM-DD' zurück, oder leer,
@@ -287,9 +297,9 @@ def generate_compliant_xrechnung(data):
         ET.SubElement(delivery, f"{{{CBC}}}ActualDeliveryDate").text = parse_to_strict_xml_date(data["delivery_date"])
 
     payment_means = ET.SubElement(root, f"{{{CAC}}}PaymentMeans")
-    # BT-81 Zahlungsart: Code 58 = SEPA-Überweisung (statt 30, das für Überweisungen
+    # BT-81 Zahlungsart: Standard bleibt 58 (SEPA-Ueberweisung), aber ueber
-    # außerhalb des SEPA-Raums gedacht ist - VD-Valitool-169-Hinweis).
+    # PAYMENT_MEANS_CODES pro Rechnung waehlbar (siehe UN/EDIFACT 4461).
-    ET.SubElement(payment_means, f"{{{CBC}}}PaymentMeansCode").text = "58"
+    ET.SubElement(payment_means, f"{{{CBC}}}PaymentMeansCode").text = str(data.get("payment_means_code", "58"))
     payee_acc = ET.SubElement(payment_means, f"{{{CAC}}}PayeeFinancialAccount")
     ET.SubElement(payee_acc, f"{{{CBC}}}ID").text = str(data["iban"]).replace(" ", "")
 
@@ -506,10 +516,9 @@ def generate_compliant_zugferd_cii(data):
     ET.SubElement(header_settle, f"{{{RAM}}}InvoiceCurrencyCode").text = "EUR"
 
     pay_means = ET.SubElement(header_settle, f"{{{RAM}}}SpecifiedTradeSettlementPaymentMeans")
-    # BT-81 Zahlungsart: Code 58 = SEPA-Überweisung. Code 30 ist für Überweisungen AUSSERHALB
+    # BT-81 Zahlungsart: Standard bleibt 58 (SEPA-Ueberweisung), aber ueber
-    # des SEPA-Raums gedacht (VD-Valitool-169-Hinweis) - da hier immer eine IBAN verwendet wird,
+    # PAYMENT_MEANS_CODES pro Rechnung waehlbar (siehe UN/EDIFACT 4461).
-    # ist 58 der korrekte Code.
+    ET.SubElement(pay_means, f"{{{RAM}}}TypeCode").text = str(data.get("payment_means_code", "58"))
-    ET.SubElement(pay_means, f"{{{RAM}}}TypeCode").text = "58"
     payee_acc = ET.SubElement(pay_means, f"{{{RAM}}}PayeePartyCreditorFinancialAccount")
     ET.SubElement(payee_acc, f"{{{RAM}}}IBANID").text = str(data["iban"]).replace(" ", "")
 

main.py

@@ -11,6 +11,7 @@ from invoice_logic import (
     InvoiceMetadata,
     VERKAEUFER,
     VERKAEUFER_IBAN,
+    PAYMENT_MEANS_CODES,
     berechne_faelligkeit,
     kaufmaennisches_runden,
     clean_german_float,
@@ -252,6 +253,17 @@ with col2:
             r_zip = st.text_input("PLZ (BT-53)", value=data.get("recipient_zip", ""))
             r_city = st.text_input("Stadt (BT-52) :red[*]", value=data.get("recipient_city", ""))
 
+        st.markdown("---")
+
+        payment_means_codes_list = list(PAYMENT_MEANS_CODES.keys())
+        payment_means_labels = [f"{code} - {PAYMENT_MEANS_CODES[code]}" for code in payment_means_codes_list]
+        selected_payment_means_label = st.selectbox(
+            "Zahlungsmittel (BT-81)",
+            options=payment_means_labels,
+            index=payment_means_codes_list.index("58"),
+        )
+        selected_payment_means_code = selected_payment_means_label.split(" - ")[0]
+
         st.markdown("### 3. Positionen")
         
         if st.button("➕ Neue Position hinzufügen"):
@@ -335,6 +347,7 @@ with col2:
             "recipient_street": r_street, "recipient_zip": r_zip, "recipient_city": r_city,
             "items": edited_items, "total_net_amount": computed_net_amount, "total_vat_amount": computed_vat_amount,
             "vat_rate_percent": vat_rate, "total_gross_amount": computed_gross_amount, "iban": VERKAEUFER_IBAN,
+            "payment_means_code": selected_payment_means_code,
             "delivery_note_id": dn_id,
             "order_id": o_id,
             "contract_id": c_id,

tests/test_invoice_logic.py

@@ -11,6 +11,7 @@ from invoice_logic import (
     generate_compliant_xrechnung,
     generate_compliant_zugferd_cii,
     VERKAEUFER_IBAN,
+    PAYMENT_MEANS_CODES,
 )
 
 
@@ -94,3 +95,38 @@ def test_map_unece_unit_code_hours():
 
 def test_parse_to_strict_xml_date_german_format():
     assert parse_to_strict_xml_date("15.01.2026") == "2026-01-15"
+
+
+def test_payment_means_codes_contains_expected_entries():
+    assert PAYMENT_MEANS_CODES["58"] == "SEPA-Überweisung"
+    assert set(["30", "31", "42", "48", "58"]).issubset(PAYMENT_MEANS_CODES.keys())
+
+
+def test_generate_compliant_xrechnung_uses_dynamic_payment_means_code():
+    data = _single_rate_invoice()
+    data["payment_means_code"] = "31"
+    xml_str = generate_compliant_xrechnung(data)
+    root = ET.fromstring(xml_str.encode("utf-8"))
+    ns = {"cbc": "urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2",
+          "cac": "urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"}
+    code = root.find(".//cac:PaymentMeans/cbc:PaymentMeansCode", ns).text
+    assert code == "31"
+
+
+def test_generate_compliant_xrechnung_defaults_payment_means_code_to_58():
+    xml_str = generate_compliant_xrechnung(_single_rate_invoice())
+    root = ET.fromstring(xml_str.encode("utf-8"))
+    ns = {"cbc": "urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2",
+          "cac": "urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"}
+    code = root.find(".//cac:PaymentMeans/cbc:PaymentMeansCode", ns).text
+    assert code == "58"
+
+
+def test_generate_compliant_zugferd_cii_uses_dynamic_payment_means_code():
+    data = _single_rate_invoice()
+    data["payment_means_code"] = "48"
+    xml_str = generate_compliant_zugferd_cii(data)
+    root = ET.fromstring(xml_str.encode("utf-8"))
+    ns = {"ram": "urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100"}
+    code = root.find(".//ram:SpecifiedTradeSettlementPaymentMeans/ram:TypeCode", ns).text
+    assert code == "48"