Added paymentDescription and buyerReference

e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/mapper/MustangMapper.kt

@@ -25,6 +25,9 @@ class MustangMapper {
         this.setZFItems(ArrayList(invoice.items.map { mapLineItem(it) }))
 
         this.dueDate = map(invoice.dueDate)
+        this.paymentTermDescription = invoice.paymentDescription
+
+        this.referenceNumber = invoice.buyerReference
     }
 
     fun mapParty(party: Party): TradeParty = TradeParty(

e-invoicing-domain/src/main/kotlin/net/codinux/invoicing/model/Invoice.kt

@@ -8,7 +8,14 @@ class Invoice(
     val sender: Party,
     val recipient: Party,
     val items: List<LineItem>,
+
     val dueDate: LocalDate? = null,
+    val paymentDescription: String? = null,
+
+    /**
+     * Unique reference number of the buyer, e.g. the Leitweg-ID required by German authorities (Behörden)
+     */
+    val buyerReference: String? = null
 ) {
     override fun toString() = "$invoicingDate $invoiceNumber to $recipient"
 }

e-invoicing-domain/src/test/kotlin/net/codinux/invoicing/test/DataGenerator.kt

@@ -5,11 +5,13 @@ import net.codinux.invoicing.model.LineItem
 import net.codinux.invoicing.model.Party
 import java.math.BigDecimal
 import java.time.LocalDate
+import java.time.format.DateTimeFormatter
 
 object DataGenerator {
 
     const val InvoiceNumber = "12345"
     val InvoicingDate = LocalDate.of(2015, 10, 21)
+    val DueDate = LocalDate.of(2016, 6, 15)
 
     const val SenderName = "Hochwürdiger Leistungserbringer"
     const val SenderStreet = "Fun Street 1"
@@ -43,8 +45,10 @@ object DataGenerator {
         sender: Party = createParty(SenderName, SenderStreet, SenderPostalCode, SenderCity, SenderCountry, SenderVatId, SenderEmail, SenderPhone),
         recipient: Party = createParty(RecipientName, RecipientStreet, RecipientPostalCode, RecipientCity, RecipientCountry, RecipientVatId, RecipientEmail, RecipientPhone),
         items: List<LineItem> = listOf(createItem()),
-        dueDate: LocalDate? = null
-    ) = Invoice(invoiceNumber, invoicingDate, sender, recipient, items, dueDate)
+        dueDate: LocalDate? = DueDate,
+        paymentDescription: String? = dueDate?.let { "Zahlbar ohne Abzug bis ${DateTimeFormatter.ofPattern("dd.MM.yyyy").format(dueDate)}" },
+        buyerReference: String? = null
+    ) = Invoice(invoiceNumber, invoicingDate, sender, recipient, items, dueDate, paymentDescription, buyerReference)
 
     fun createParty(
         name: String,