fix: Group products and parse period from invoice title

- Group identical product lines on same row
- Parse month from invoice title/notes (e.g., 'Periode May 2025')
- Assign lines to correct month from title
- Sum amounts per month and merge statuses

app/services/subscription_matrix.py

@@ -178,6 +178,7 @@ class SubscriptionMatrixService:
                 if other_ref:
                     invoice_text_parts.append(str(other_ref))
                 invoice_text = " ".join(invoice_text_parts).lower()
+                invoice_period = self._extract_period_from_text(invoice_text)
                 
                 # Process invoice lines
                 lines = invoice.get('lines', [])
@@ -194,13 +195,14 @@ class SubscriptionMatrixService:
                     ):
                         continue
                     
-                    if not product_number:
+                    if not product_number and not product_name:
                         logger.debug(f"Skipping line without product number: {line}")
                         continue
+                    product_key = product_number or (product_name or "").strip().lower()
                     
                     # Cache product name
-                    if product_number not in product_names:
-                        product_names[product_number] = product_name or f"Product {product_number}"
+                    if product_key not in product_names:
+                        product_names[product_key] = product_name or f"Product {product_number}"
                     
                     # Extract period from line
                     period_from_str = line.get('period', {}).get('from')
@@ -208,7 +210,12 @@ class SubscriptionMatrixService:
                     
                     # If no period on line, use invoice date as month
                     if not period_from_str:
-                        if invoice_date:
+                        if invoice_period:
+                            period_from = invoice_period
+                            period_to = self._end_of_month(period_from)
+                            period_from_str = period_from.isoformat().split('T')[0]
+                            period_to_str = period_to.isoformat().split('T')[0]
+                        elif invoice_date:
                             period_from_str = invoice_date
                             # Assume monthly billing if no end date
                             period_from = datetime.fromisoformat(invoice_date.replace('Z', '+00:00'))
@@ -246,9 +253,9 @@ class SubscriptionMatrixService:
                     period_label = self._format_period_label(period_from, period_to)
                     
                     # Initialize product if first time within range
-                    if product_number not in product_matrix:
+                    if product_key not in product_matrix:
                         for month_key in all_months:
-                            product_matrix[product_number][month_key] = {
+                            product_matrix[product_key][month_key] = {
                                 "amount": 0.0,
                                 "status": "missing",
                                 "invoice_number": None,
@@ -258,9 +265,9 @@ class SubscriptionMatrixService:
                             }
 
                     # Update cell
-                    cell = product_matrix[product_number][year_month]
-                    cell["amount"] = amount  # Take last amount (or sum if multiple?)
-                    cell["status"] = self._determine_status(invoice_status)
+                    cell = product_matrix[product_key][year_month]
+                    cell["amount"] += amount
+                    cell["status"] = self._merge_status(cell["status"], self._determine_status(invoice_status))
                     cell["invoice_number"] = invoice_number
                     cell["period_from"] = period_from.isoformat().split('T')[0]
                     cell["period_to"] = period_to.isoformat().split('T')[0]
@@ -331,6 +338,54 @@ class SubscriptionMatrixService:
         # Return sorted chronologically (oldest first)
         return sorted(months)
 
+    @staticmethod
+    def _end_of_month(dt: datetime) -> datetime:
+        """Return last day of the month for a given date."""
+        next_month = dt.replace(day=28) + timedelta(days=4)
+        return next_month - timedelta(days=next_month.day)
+
+    @staticmethod
+    def _extract_period_from_text(text: str) -> Optional[datetime]:
+        """Extract month/year from invoice title/notes text (e.g., 'Periode May 2025')."""
+        if not text:
+            return None
+        month_map = {
+            "january": 1, "jan": 1, "januar": 1,
+            "february": 2, "feb": 2, "februar": 2,
+            "march": 3, "mar": 3, "marts": 3,
+            "april": 4, "apr": 4,
+            "may": 5, "maj": 5,
+            "june": 6, "jun": 6, "juni": 6,
+            "july": 7, "jul": 7, "juli": 7,
+            "august": 8, "aug": 8,
+            "september": 9, "sep": 9, "sept": 9,
+            "october": 10, "oct": 10, "okt": 10, "oktober": 10,
+            "november": 11, "nov": 11,
+            "december": 12, "dec": 12
+        }
+        tokens = text.replace(".", " ").replace("/", " ").split()
+        for i, token in enumerate(tokens[:-1]):
+            month = month_map.get(token.lower())
+            if month:
+                year_token = tokens[i + 1]
+                if year_token.isdigit() and len(year_token) == 4:
+                    return datetime(int(year_token), month, 1)
+        return None
+
+    @staticmethod
+    def _merge_status(existing: str, incoming: str) -> str:
+        """Keep the most 'complete' status when multiple invoices hit same cell."""
+        priority = {
+            "missing": 0,
+            "draft": 1,
+            "invoiced": 2,
+            "paid": 3,
+            "credited": 2
+        }
+        existing_key = existing or "missing"
+        incoming_key = incoming or "missing"
+        return incoming_key if priority.get(incoming_key, 0) >= priority.get(existing_key, 0) else existing_key
+    
     @staticmethod
     def _format_period_label(period_from: datetime, period_to: datetime) -> str:
         """Format period as readable label (e.g., 'Jan', 'Jan-Mar', etc)"""