refactor: Use GST Details for e-Waybill and e-Invoice Transactions (#3227)

* refactor: use gst details for e-Waybill and e-Invoice transactions

* fix: use item gst details to update item taxes

* fix: add tax amounts while grouping

* fix: round tax totals

---------

Co-authored-by: Smit Vora <smitvora203@gmail.com>
(cherry picked from commit 82699b0)

# Conflicts:
#	india_compliance/gst_india/utils/transaction_data.py

Author: Ninad1306

india_compliance/gst_india/utils/transaction_data.py

@@ -9,8 +9,11 @@
     GST_REFUND_TAX_TYPES,
     GST_TAX_RATES,
     GST_TAX_TYPES,
+<<<<<<< HEAD
     SUBCONTRACTING_DOCTYPES,
     TAXABLE_GST_TREATMENTS,
+=======
+>>>>>>> 82699b04 (refactor: Use GST Details for e-Waybill and e-Invoice Transactions (#3227))
 )
 from india_compliance.gst_india.constants.e_waybill import (
     TRANSPORT_MODES,
@@ -72,13 +75,29 @@ def set_transaction_details(self):
 
         total = 0
         total_taxable_value = 0
+        tax_total_keys = tuple(f"total_{tax}_amount" for tax in GST_TAX_TYPES)
+
+        # Initialize all tax totals to 0
+        self.transaction_details.update({key: 0 for key in tax_total_keys})
 
         for row in self.doc.items:
             total += row.taxable_value
 
             if row.gst_treatment in TAXABLE_GST_TREATMENTS:
                 total_taxable_value += row.taxable_value
 
+            if self.is_purchase_rcm:
+                continue
+
+            # eg: Skip reverse charge tax for e-Waybill
+            if self.doc.get("is_reverse_charge") and getattr(
+                self, "exclude_reverse_charge_tax", False
+            ):
+                continue
+
+            for tax_key in tax_total_keys:
+                self.transaction_details[tax_key] += abs(row.get(tax_key[6:], 0))
+
         self.transaction_details.update(
             {
                 "company_name": self.sanitize_value(self.doc.company),
@@ -95,9 +114,7 @@ def set_transaction_details(self):
                     self.rounded(total - total_taxable_value)
                 ),
                 "rounding_adjustment": rounding_adjustment,
-                "grand_total": abs(
-                    self.doc.get(grand_total_fieldname)
-                ),  # rounded after updating refund amounts
+                "grand_total": abs(self.rounded(self.doc.get(grand_total_fieldname))),
                 "grand_total_in_foreign_currency": (
                     abs(self.rounded(self.doc.grand_total))
                     if self.doc.get("currency", "INR") != "INR"
@@ -113,51 +130,37 @@ def set_transaction_details(self):
                 "other_charges": 0,
             }
         )
+
+        # Round tax totals
+        for tax_key in tax_total_keys:
+            self.transaction_details[tax_key] = self.rounded(
+                self.transaction_details[tax_key]
+            )
+
         self.update_transaction_details()
-        self.update_transaction_tax_details()
+        self.update_discount_and_other_charges(tax_total_keys)
 
     def update_transaction_details(self):
-        # to be overrridden
+        # to be overridden
         pass
 
-    def update_transaction_tax_details(self):
-        tax_total_keys = tuple(f"total_{tax}_amount" for tax in GST_TAX_TYPES)
-
-        for key in tax_total_keys:
-            self.transaction_details[key] = 0
-
+    def update_totals_for_refund(self):
         for row in self.doc.taxes:
-            if row.gst_tax_type in GST_REFUND_TAX_TYPES:
-                self.transaction_details.grand_total -= (
-                    row.base_tax_amount_after_discount_amount
-                )
-                continue
-
-            if (
-                not row.tax_amount
-                or self.is_purchase_rcm
-                or row.gst_tax_type not in GST_TAX_TYPES
-            ):
+            if row.gst_tax_type not in GST_REFUND_TAX_TYPES:
                 continue
 
-            # eg: Skip reverse charge tax for e-Waybill
-            if self.doc.get("is_reverse_charge") and getattr(
-                self, "exclude_reverse_charge_tax", False
-            ):
-                continue
-
-            tax_key = f"total_{row.gst_tax_type}_amount"
-            tax_amount = (
-                row.get("base_tax_amount_after_discount_amount") or row.tax_amount
+            self.transaction_details.grand_total -= (
+                row.base_tax_amount_after_discount_amount
             )
-            self.transaction_details.setdefault(tax_key, 0)
-            self.transaction_details[tax_key] += abs(self.rounded(tax_amount))
 
-        # Ensure that grand total is rounded as it is updated above
+        # Ensure that grand total is rounded as it may be updated above
         self.transaction_details.grand_total = self.rounded(
             self.transaction_details.grand_total
         )
 
+    def update_discount_and_other_charges(self, tax_total_keys):
+        self.update_totals_for_refund()  # Ensure grand total is correct for refund
+
         # Other Charges
         current_total = 0
 
@@ -349,7 +352,13 @@ def group_same_items(self):
             item = grouped_items.setdefault(
                 row.item_code,
                 frappe._dict(
-                    {**row.as_dict(), "idx": 0, "qty": 0.00, "taxable_value": 0.00}
+                    {
+                        **row.as_dict(),
+                        "idx": 0,
+                        "qty": 0.00,
+                        "taxable_value": 0.00,
+                        **{f"{tax}_amount": 0.00 for tax in GST_TAX_TYPES},
+                    },
                 ),
             )
 
@@ -360,6 +369,9 @@ def group_same_items(self):
             item.qty += row.qty
             item.taxable_value += row.taxable_value
 
+            for tax in GST_TAX_TYPES:
+                item[f"{tax}_amount"] += row.get(f"{tax}_amount", 0)
+
         return list(grouped_items.values())
 
     def set_item_list(self):
@@ -373,11 +385,17 @@ def update_item_details(self, item_details, item):
         pass
 
     def update_item_tax_details(self, item_details, item):
-        if self.doc.doctype in SUBCONTRACTING_DOCTYPES:
-            self.update_item_tax_details_using_item_gst_details(item_details, item)
+        for tax in GST_TAX_TYPES:
+            tax_amount = self.get_progressive_item_tax_amount(
+                item.get(f"{tax}_amount"), tax
+            )
 
-        else:
-            self.update_item_tax_details_using_taxes(item_details, item)
+            item_details.update(
+                {
+                    f"{tax}_amount": tax_amount,
+                    f"{tax}_rate": item.get(f"{tax}_rate"),
+                }
+            )
 
         tax_rate = sum(
             self.rounded(item_details.get(f"{tax}_rate", 0), 3)
@@ -401,6 +419,7 @@ def update_item_tax_details(self, item_details, item):
             }
         )
 
+<<<<<<< HEAD
     def update_item_tax_details_using_taxes(self, item_details, item):
         for tax in GST_TAX_TYPES:
             item_details.update({f"{tax}_amount": 0, f"{tax}_rate": 0})
@@ -447,6 +466,8 @@ def update_item_tax_details_using_item_gst_details(self, item_details, item):
                 }
             )
 
+=======
+>>>>>>> 82699b04 (refactor: Use GST Details for e-Waybill and e-Invoice Transactions (#3227))
     def get_progressive_item_tax_amount(self, amount, tax_type):
         """
         Helper function to calculate progressive tax amount for an item to remove