fix: negative stock balance (backport frappe#44990) (frappe#44996)

* fix: negative stock balance (frappe#44990)

(cherry picked from commit 7c4aecf)

# Conflicts:
#	erpnext/stock/deprecated_serial_batch.py

* chore: fix conflicts

---------

Co-authored-by: rohitwaghchaure <[email protected]>

erpnext/stock/deprecated_serial_batch.py

@@ -181,6 +181,9 @@ def calculate_avg_rate_for_non_batchwise_valuation(self):
 			stock_value_change = self.batch_avg_rate[batch_no] * ledger.qty
 			self.stock_value_change += stock_value_change
 
+			self.non_batchwise_balance_value[batch_no] -= stock_value_change
+			self.non_batchwise_balance_qty[batch_no] -= ledger.qty
+
 			frappe.db.set_value(
 				"Serial and Batch Entry",
 				ledger.name,
@@ -220,7 +223,6 @@ def set_balance_value_from_sl_entries(self) -> None:
 			.select(
 				sle.batch_no,
 				Sum(sle.actual_qty).as_("batch_qty"),
-				Sum(sle.stock_value_difference).as_("batch_value"),
 			)
 			.where(
 				(sle.item_code == self.sle.item_code)
@@ -237,11 +239,59 @@ def set_balance_value_from_sl_entries(self) -> None:
 		if self.sle.name:
 			query = query.where(sle.name != self.sle.name)
 
-		for d in query.run(as_dict=True):
-			self.non_batchwise_balance_value[d.batch_no] += flt(d.batch_value)
-			self.non_batchwise_balance_qty[d.batch_no] += flt(d.batch_qty)
+		batch_data = query.run(as_dict=True)
+		for d in batch_data:
 			self.available_qty[d.batch_no] += flt(d.batch_qty)
 
+		last_sle = self.get_last_sle_for_non_batch()
+		for d in batch_data:
+			self.non_batchwise_balance_value[d.batch_no] += flt(last_sle.stock_value)
+			self.non_batchwise_balance_qty[d.batch_no] += flt(last_sle.qty_after_transaction)
+
+	def get_last_sle_for_non_batch(self):
+		from erpnext.stock.utils import get_combine_datetime
+
+		sle = frappe.qb.DocType("Stock Ledger Entry")
+		batch = frappe.qb.DocType("Batch")
+
+		posting_datetime = get_combine_datetime(self.sle.posting_date, self.sle.posting_time)
+		if not self.sle.creation:
+			posting_datetime = posting_datetime + datetime.timedelta(milliseconds=1)
+
+		timestamp_condition = sle.posting_datetime < posting_datetime
+
+		if self.sle.creation:
+			timestamp_condition |= (sle.posting_datetime == posting_datetime) & (
+				sle.creation < self.sle.creation
+			)
+
+		query = (
+			frappe.qb.from_(sle)
+			.inner_join(batch)
+			.on(sle.batch_no == batch.name)
+			.select(
+				sle.stock_value,
+				sle.qty_after_transaction,
+			)
+			.where(
+				(sle.item_code == self.sle.item_code)
+				& (sle.warehouse == self.sle.warehouse)
+				& (sle.batch_no.isnotnull())
+				& (batch.use_batchwise_valuation == 0)
+				& (sle.is_cancelled == 0)
+			)
+			.where(timestamp_condition)
+			.orderby(sle.posting_datetime, order=Order.desc)
+			.orderby(sle.creation, order=Order.desc)
+			.limit(1)
+		)
+
+		if self.sle.name:
+			query = query.where(sle.name != self.sle.name)
+
+		data = query.run(as_dict=True)
+		return data[0] if data else {}
+
 	@deprecated
 	def set_balance_value_from_bundle(self) -> None:
 		bundle = frappe.qb.DocType("Serial and Batch Bundle")

erpnext/stock/doctype/serial_and_batch_bundle/test_serial_and_batch_bundle.py

@@ -166,7 +166,7 @@ def test_old_batch_valuation(self):
 		for qty, valuation in {10: 100, 20: 200}.items():
 			stock_queue.append([qty, valuation])
 			qty_after_transaction += qty
-			balance_value += qty_after_transaction * valuation
+			balance_value += qty * valuation
 
 			doc = frappe.get_doc(
 				{
@@ -177,6 +177,7 @@ def test_old_batch_valuation(self):
 					"incoming_rate": valuation,
 					"qty_after_transaction": qty_after_transaction,
 					"stock_value_difference": valuation * qty,
+					"stock_value": balance_value,
 					"balance_value": balance_value,
 					"valuation_rate": balance_value / qty_after_transaction,
 					"actual_qty": qty,