fix(Sales Invoice): Fix GL Entry creation for Return Invoices linked with Assets
diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
index 58a2a33..347d2f5 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
@@ -13,7 +13,7 @@
 from erpnext.stock.doctype.delivery_note.delivery_note import update_billed_amount_based_on_so
 from erpnext.projects.doctype.timesheet.timesheet import get_projectwise_timesheet_data
 from erpnext.assets.doctype.asset.depreciation \
-	import get_disposal_account_and_cost_center, get_gl_entries_on_asset_disposal
+	import get_disposal_account_and_cost_center, get_gl_entries_on_asset_movement
 from erpnext.stock.doctype.batch.batch import set_batch_nos
 from erpnext.stock.doctype.serial_no.serial_no import get_serial_nos, get_delivery_note_serial_no
 from erpnext.setup.doctype.company.company import update_company_current_month_sales
@@ -928,8 +928,12 @@
 						frappe.throw(_("Select finance book for the item {0} at row {1}")
 							.format(item.item_code, item.idx))
 
-					fixed_asset_gl_entries = get_gl_entries_on_asset_disposal(asset,
-						item.base_net_amount, item.finance_book)
+					if self.is_return:
+						fixed_asset_gl_entries = get_gl_entries_on_asset_movement(asset,
+							item.base_net_amount, item.finance_book, True)
+					else:
+						fixed_asset_gl_entries = get_gl_entries_on_asset_movement(asset,
+							item.base_net_amount, item.finance_book)
 
 					for gle in fixed_asset_gl_entries:
 						gle["against"] = self.customer
diff --git a/erpnext/assets/doctype/asset/depreciation.py b/erpnext/assets/doctype/asset/depreciation.py
index 8f0afb4..a18f427 100644
--- a/erpnext/assets/doctype/asset/depreciation.py
+++ b/erpnext/assets/doctype/asset/depreciation.py
@@ -147,7 +147,7 @@
 	je.company = asset.company
 	je.remark = "Scrap Entry for asset {0}".format(asset_name)
 
-	for entry in get_gl_entries_on_asset_disposal(asset):
+	for entry in get_gl_entries_on_asset_movement(asset):
 		entry.update({
 			"reference_type": "Asset",
 			"reference_name": asset_name
@@ -177,7 +177,7 @@
 	asset.set_status()
 
 @frappe.whitelist()
-def get_gl_entries_on_asset_disposal(asset, selling_amount=0, finance_book=None):
+def get_gl_entries_on_asset_movement(asset, selling_amount=0, finance_book=None, is_return = False):
 	fixed_asset_account, accumulated_depr_account, depr_expense_account = get_depreciation_accounts(asset)
 	disposal_account, depreciation_cost_center = get_disposal_account_and_cost_center(asset.company)
 	depreciation_cost_center = asset.cost_center or depreciation_cost_center
@@ -193,6 +193,44 @@
 		if asset.calculate_depreciation else asset.value_after_depreciation)
 	accumulated_depr_amount = flt(asset.gross_purchase_amount) - flt(value_after_depreciation)
 
+	if is_return:
+		gl_entries = get_gl_entries_on_asset_regain(fixed_asset_account, asset, depreciation_cost_center, accumulated_depr_account, accumulated_depr_amount)
+		profit_amount = abs(flt(value_after_depreciation)) - abs(flt(selling_amount))
+		
+	else:
+		gl_entries = get_gl_entries_on_asset_disposal(fixed_asset_account, asset, depreciation_cost_center, accumulated_depr_account, accumulated_depr_amount)
+		profit_amount = flt(selling_amount) - flt(value_after_depreciation)
+
+	if profit_amount:
+		debit_or_credit = "debit" if profit_amount < 0 else "credit"
+		gl_entries.append({
+			"account": disposal_account,
+			"cost_center": depreciation_cost_center,
+			debit_or_credit: abs(profit_amount),
+			debit_or_credit + "_in_account_currency": abs(profit_amount)
+		})
+
+	return gl_entries
+
+def get_gl_entries_on_asset_regain(fixed_asset_account, asset, depreciation_cost_center, accumulated_depr_account, accumulated_depr_amount):
+	gl_entries = [
+		{
+			"account": fixed_asset_account,
+			"debit_in_account_currency": asset.gross_purchase_amount,
+			"debit": asset.gross_purchase_amount,
+			"cost_center": depreciation_cost_center
+		},
+		{
+			"account": accumulated_depr_account,
+			"credit_in_account_currency": accumulated_depr_amount,
+			"credit": accumulated_depr_amount,
+			"cost_center": depreciation_cost_center
+		}
+	]
+
+	return gl_entries
+
+def get_gl_entries_on_asset_disposal(fixed_asset_account, asset, depreciation_cost_center, accumulated_depr_account, accumulated_depr_amount):
 	gl_entries = [
 		{
 			"account": fixed_asset_account,
@@ -208,16 +246,6 @@
 		}
 	]
 
-	profit_amount = flt(selling_amount) - flt(value_after_depreciation)
-	if profit_amount:
-		debit_or_credit = "debit" if profit_amount < 0 else "credit"
-		gl_entries.append({
-			"account": disposal_account,
-			"cost_center": depreciation_cost_center,
-			debit_or_credit: abs(profit_amount),
-			debit_or_credit + "_in_account_currency": abs(profit_amount)
-		})
-
 	return gl_entries
 
 @frappe.whitelist()