add synchronization with Purcahse Order, change on vendor bills will change PO

models/account_move_line.py

@@ -104,3 +104,50 @@ class AccountMoveLine(models.Model):
                 new_price_unit = derived_price_subtotal / line.quantity
                 
                 line.price_unit = new_price_unit
+
+    def write(self, vals):
+        """
+        Override write to sync changes to linked Purchase Order Line.
+        """
+        res = super(AccountMoveLine, self).write(vals)
+        
+        # Check if we need to sync
+        if 'price_unit' in vals or 'quantity' in vals:
+            for line in self:
+                # Only for vendor bills and if linked to a PO line
+                if line.move_id.move_type in ('in_invoice', 'in_refund') and line.purchase_line_id:
+                    po_line = line.purchase_line_id
+                    
+                    # 1. Sync Price
+                    # Convert bill price (in bill currency) to PO currency
+                    bill_currency = line.currency_id or line.move_id.currency_id
+                    po_currency = po_line.currency_id or po_line.order_id.currency_id
+                    price_unit = line.price_unit
+
+                    if bill_currency and po_currency and bill_currency != po_currency:
+                        price_unit = bill_currency._convert(
+                            price_unit, 
+                            po_currency, 
+                            line.company_id, 
+                            line.move_id.invoice_date or fields.Date.today()
+                        )
+
+                    # Convert Price to PO UoM if needed
+                    if line.product_uom_id and po_line.product_uom and line.product_uom_id != po_line.product_uom:
+                        price_unit = line.product_uom_id._compute_price(price_unit, po_line.product_uom)
+                    
+                    # 2. Sync Quantity
+                    # Convert bill qty (in bill UoM) to PO UoM
+                    product_qty = line.quantity
+                    if line.product_uom_id and po_line.product_uom and line.product_uom_id != po_line.product_uom:
+                        product_qty = line.product_uom_id._compute_quantity(product_qty, po_line.product_uom)
+
+                    # Update PO Line
+                    # We update both to ensure consistency
+                    po_line.write({
+                        'price_unit': price_unit,
+                        'product_qty': product_qty,
+                    })
+                        
+        return res
+