update

ts/formats/cii/zugferd/zugferd.decoder.ts

@@ -70,7 +70,20 @@ export class ZUGFeRDDecoder extends CIIBaseDecoder {
     // const totalAmount = this.getNumber('//ram:GrandTotalAmount');
 
     // Extract notes
-    const notes = this.extractNotes();
+    const allNotes = this.extractNotes();
+
+    // Extract subject and notes separately
+    // If we have notes, the first one might be the subject
+    let subject = `Invoice ${invoiceId}`;
+    let notes = [...allNotes];
+    
+    // If the first note doesn't look like a payment term or other standard note,
+    // treat it as the subject
+    if (allNotes.length > 0 && !allNotes[0].toLowerCase().includes('due in') && 
+        !allNotes[0].toLowerCase().includes('payment')) {
+      subject = allNotes[0];
+      notes = allNotes.slice(1); // Remove subject from notes
+    }
 
     // Check for reverse charge
     const reverseCharge = this.exists('//ram:SpecifiedTradeAllowanceCharge/ram:ReasonCode[text()="62"]');
@@ -91,7 +104,7 @@ export class ZUGFeRDDecoder extends CIIBaseDecoder {
       incidenceId: invoiceId,
       from: seller,
       to: buyer,
-      subject: `Invoice ${invoiceId}`,
+      subject: subject,
       items: items,
       dueInDays: dueInDays,
       reverseCharge: reverseCharge,

ts/formats/cii/zugferd/zugferd.encoder.ts

@@ -152,15 +152,22 @@ export class ZUGFeRDEncoder extends CIIBaseEncoder {
     issueDateElement.appendChild(dateStringElement);
     documentElement.appendChild(issueDateElement);
 
-    // Add notes if available
+    // Add notes - include subject as first note if it exists
+    const allNotes: string[] = [];
+    if (invoice.subject && invoice.subject.trim()) {
+      allNotes.push(invoice.subject);
+    }
     if (invoice.notes && invoice.notes.length > 0) {
-      for (const note of invoice.notes) {
-        const noteElement = doc.createElement('ram:IncludedNote');
-        const contentElement = doc.createElement('ram:Content');
-        contentElement.textContent = note;
-        noteElement.appendChild(contentElement);
-        documentElement.appendChild(noteElement);
-      }
+      allNotes.push(...invoice.notes);
+    }
+    
+    // Write all notes
+    for (const note of allNotes) {
+      const noteElement = doc.createElement('ram:IncludedNote');
+      const contentElement = doc.createElement('ram:Content');
+      contentElement.textContent = note;
+      noteElement.appendChild(contentElement);
+      documentElement.appendChild(noteElement);
     }
 
     // Create transaction element if it doesn't exist

ts/formats/cii/zugferd/zugferd.v1.decoder.ts

@@ -85,7 +85,20 @@ export class ZUGFeRDV1Decoder extends CIIBaseDecoder {
     // const totalAmount = this.getNumber('//ram:GrandTotalAmount');
 
     // Extract notes
-    const notes = this.extractNotes();
+    const allNotes = this.extractNotes();
+
+    // Extract subject and notes separately
+    // If we have notes, the first one might be the subject
+    let subject = `Invoice ${invoiceId}`;
+    let notes = [...allNotes];
+    
+    // If the first note doesn't look like a payment term or other standard note,
+    // treat it as the subject
+    if (allNotes.length > 0 && !allNotes[0].toLowerCase().includes('due in') && 
+        !allNotes[0].toLowerCase().includes('payment')) {
+      subject = allNotes[0];
+      notes = allNotes.slice(1); // Remove subject from notes
+    }
 
     // Check for reverse charge
     const reverseCharge = this.exists('//ram:SpecifiedTradeAllowanceCharge/ram:ReasonCode[text()="62"]');
@@ -106,7 +119,7 @@ export class ZUGFeRDV1Decoder extends CIIBaseDecoder {
       incidenceId: invoiceId,
       from: seller,
       to: buyer,
-      subject: `Invoice ${invoiceId}`,
+      subject: subject,
       items: items,
       dueInDays: dueInDays,
       reverseCharge: reverseCharge,