feat: Logic for query and report creation for inactive items
diff --git a/erpnext/stock/report/inactive_items/inactive_items.py b/erpnext/stock/report/inactive_items/inactive_items.py
index 8aeb243..95cec7b 100644
--- a/erpnext/stock/report/inactive_items/inactive_items.py
+++ b/erpnext/stock/report/inactive_items/inactive_items.py
@@ -3,9 +3,13 @@
 
 from __future__ import unicode_literals
 import frappe
+from frappe.utils import getdate, add_days, today, cint
+from frappe import _
 
 def execute(filters=None):
-	columns, data = [], []
+
+	columns = get_columns()
+	data = get_data(filters)
 	return columns, data
 
 def get_columns():
@@ -26,12 +30,20 @@
 			"width": 100
 		},
 		{
-			"fieldname": "item",
+			"fieldname": "item_name",
 			"fieldtype": "Link",
-			"label": _("Item"),
+			"options": "Item",
+			"label": "Item",
+			"width": 100
+		},
+		{
+			"fieldname": "Item Name",
+			"fieldtype": "Link",
+			"label": _("Item Name"),
 			"options": "Item",
 			"width": 100
 		},
+
 		{
 			"fieldname": "customer",
 			"fieldtype": "Link",
@@ -58,3 +70,80 @@
 			"width": 100
 		},
 	]
+
+	return columns
+
+
+def get_data(filters):
+
+	data = []
+	items = get_items(filters)
+	sales_invoice_data = get_sales_details(filters)
+
+	for item in items:
+		if sales_invoice_data.get(item.name):
+			item_obj = sales_invoice_data[item.name]
+			if item_obj.days_since_last_order > cint(filters['days']):
+				row = {
+					"territory": item_obj.territory,
+					"item_group": item_obj.item_group,
+					"item": item_obj.name,
+					"item_name": item_obj.item_name,
+					"customer": item_obj.customer,
+					"last_order_date": item_obj.last_order_date,
+					"qty": item_obj.qty,
+					"days_since_last_order": item_obj.days_since_last_order
+				}
+				data.append(row)
+		else:
+			row = {
+				"item_group": item.item_group,
+				"item": item.name,
+				"item_name": item.item_name
+			}
+			data.append(row)
+
+	return data
+
+
+def get_sales_details(filters):
+
+	data = []
+	item_details_map = {}
+
+	date_field = "s.transaction_date" if filters["based_on"] == "Sales Order" else "s.posting_date"
+
+	sales_data = frappe.db.sql("""
+		select s.territory, s.customer, si.item_group, si.item_name, si.qty, {date_field} as last_order_date,
+		DATEDIFF(CURDATE(), {date_field}) as days_since_last_order
+		from `tab{doctype}` s, `tab{doctype} Item` si
+		where s.name = si.parent and s.docstatus = 1
+		group by si.name order by days_since_last_order """
+		.format(date_field = date_field, doctype = filters['based_on']), as_dict=1)
+
+	for d in sales_data:
+		item_details_map.setdefault(d.item_name, d)
+
+	return item_details_map
+
+def get_items(filters):
+
+	filters_dict = {
+		"disabled": 0,
+		"is_stock_item": 1
+	}
+
+	if filters.get("item_group"):
+		filters_dict.update({
+			"item_group": filters["item_group"]
+		})
+
+	if filters.get("item"):
+		filters_dict.update({
+			"name": filtesr["item"]
+		})
+
+	items = frappe.get_all("Item", fields=["name", "item_group", "item_name"], filters=filters_dict)
+
+	return items
+