From e3cd35b9594f78cfcccab1472cb9ba4bc9ba3632 Mon Sep 17 00:00:00 2001
From: Nabin Hait <nabinhait@gmail.com>
Date: Mon, 15 Jan 2024 16:54:19 +0530
Subject: [PATCH] fix: WDV as per IT Act: calculate yearly amount first and
 then split it based on months

(cherry picked from commit 22bd6a54b24129403e0b399938bddcaa9d630cae)
---
 .../asset_depreciation_schedule.py            | 40 ++++++++++++++-----
 1 file changed, 29 insertions(+), 11 deletions(-)

diff --git a/erpnext/assets/doctype/asset_depreciation_schedule/asset_depreciation_schedule.py b/erpnext/assets/doctype/asset_depreciation_schedule/asset_depreciation_schedule.py
index 74d2aa71ff..ffb50ebe45 100644
--- a/erpnext/assets/doctype/asset_depreciation_schedule/asset_depreciation_schedule.py
+++ b/erpnext/assets/doctype/asset_depreciation_schedule/asset_depreciation_schedule.py
@@ -7,6 +7,7 @@ from frappe.model.document import Document
 from frappe.utils import (
 	add_days,
 	add_months,
+	add_years,
 	cint,
 	date_diff,
 	flt,
@@ -18,6 +19,7 @@ from frappe.utils import (
 )
 
 import erpnext
+from erpnext.accounts.utils import get_fiscal_year
 
 
 class AssetDepreciationSchedule(Document):
@@ -283,12 +285,20 @@ class AssetDepreciationSchedule(Document):
 		depreciation_amount = 0
 
 		number_of_pending_depreciations = final_number_of_depreciations - start
-
+		yearly_opening_wdv = value_after_depreciation
+		current_fiscal_year_end_date = None
 		for n in range(start, final_number_of_depreciations):
 			# If depreciation is already completed (for double declining balance)
 			if skip_row:
 				continue
 
+			schedule_date = add_months(row.depreciation_start_date, n * cint(row.frequency_of_depreciation))
+			if not current_fiscal_year_end_date:
+				current_fiscal_year_end_date = get_fiscal_year(row.depreciation_start_date)[2]
+			elif getdate(schedule_date) > getdate(current_fiscal_year_end_date):
+				current_fiscal_year_end_date = add_years(current_fiscal_year_end_date, 1)
+				yearly_opening_wdv = value_after_depreciation
+
 			if n > 0 and len(self.get("depreciation_schedule")) > n - 1:
 				prev_depreciation_amount = self.get("depreciation_schedule")[n - 1].depreciation_amount
 			else:
@@ -298,6 +308,7 @@ class AssetDepreciationSchedule(Document):
 				self,
 				asset_doc,
 				value_after_depreciation,
+				yearly_opening_wdv,
 				row,
 				n,
 				prev_depreciation_amount,
@@ -401,8 +412,9 @@ class AssetDepreciationSchedule(Document):
 
 			if not depreciation_amount:
 				continue
-			value_after_depreciation -= flt(
-				depreciation_amount, asset_doc.precision("gross_purchase_amount")
+			value_after_depreciation = flt(
+				value_after_depreciation - flt(depreciation_amount),
+				asset_doc.precision("gross_purchase_amount"),
 			)
 
 			# Adjust depreciation amount in the last period based on the expected value after useful life
@@ -582,6 +594,7 @@ def get_depreciation_amount(
 	asset_depr_schedule,
 	asset,
 	depreciable_value,
+	yearly_opening_wdv,
 	fb_row,
 	schedule_idx=0,
 	prev_depreciation_amount=0,
@@ -597,6 +610,7 @@ def get_depreciation_amount(
 			asset,
 			fb_row,
 			depreciable_value,
+			yearly_opening_wdv,
 			schedule_idx,
 			prev_depreciation_amount,
 			has_wdv_or_dd_non_yearly_pro_rata,
@@ -744,19 +758,23 @@ def get_wdv_or_dd_depr_amount(
 	asset,
 	fb_row,
 	depreciable_value,
+	yearly_opening_wdv,
 	schedule_idx,
 	prev_depreciation_amount,
 	has_wdv_or_dd_non_yearly_pro_rata,
 	asset_depr_schedule,
 ):
-	return get_default_wdv_or_dd_depr_amount(
-		asset,
-		fb_row,
-		depreciable_value,
-		schedule_idx,
-		prev_depreciation_amount,
-		has_wdv_or_dd_non_yearly_pro_rata,
-		asset_depr_schedule,
+	return (
+		get_default_wdv_or_dd_depr_amount(
+			asset,
+			fb_row,
+			depreciable_value,
+			schedule_idx,
+			prev_depreciation_amount,
+			has_wdv_or_dd_non_yearly_pro_rata,
+			asset_depr_schedule,
+		),
+		None,
 	)