diff --git a/erpnext/selling/utils.py b/erpnext/selling/utils.py
new file mode 100644
index 0000000..7949e47
--- /dev/null
+++ b/erpnext/selling/utils.py
@@ -0,0 +1,210 @@
+# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
+# License: GNU General Public License v3. See license.txt
+
+from __future__ import unicode_literals
+import webnotes
+from webnotes import msgprint, _
+from webnotes.utils import flt, cint, comma_and
+import json
+
+def get_customer_list(doctype, txt, searchfield, start, page_len, filters):
+	if webnotes.conn.get_default("cust_master_name") == "Customer Name":
+		fields = ["name", "customer_group", "territory"]
+	else:
+		fields = ["name", "customer_name", "customer_group", "territory"]
+		
+	return webnotes.conn.sql("""select %s from `tabCustomer` where docstatus < 2 
+		and (%s like %s or customer_name like %s) order by 
+		case when name like %s then 0 else 1 end,
+		case when customer_name like %s then 0 else 1 end,
+		name, customer_name limit %s, %s""" % 
+		(", ".join(fields), searchfield, "%s", "%s", "%s", "%s", "%s", "%s"), 
+		("%%%s%%" % txt, "%%%s%%" % txt, "%%%s%%" % txt, "%%%s%%" % txt, start, page_len))
+		
+@webnotes.whitelist()
+def get_item_details(args):
+	"""
+		args = {
+			"item_code": "",
+			"warehouse": None,
+			"customer": "",
+			"conversion_rate": 1.0,
+			"selling_price_list": None,
+			"price_list_currency": None,
+			"plc_conversion_rate": 1.0
+		}
+	"""
+
+	if isinstance(args, basestring):
+		args = json.loads(args)
+	args = webnotes._dict(args)
+	
+	if args.barcode:
+		args.item_code = _get_item_code(barcode=args.barcode)
+	elif not args.item_code and args.serial_no:
+		args.item_code = _get_item_code(serial_no=args.serial_no)
+	
+	item_bean = webnotes.bean("Item", args.item_code)
+	
+	_validate_item_details(args, item_bean.doc)
+	
+	meta = webnotes.get_doctype(args.doctype)
+
+	# hack! for Sales Order Item
+	warehouse_fieldname = "warehouse"
+	if meta.get_field("reserved_warehouse", parentfield=args.parentfield):
+		warehouse_fieldname = "reserved_warehouse"
+	
+	out = _get_basic_details(args, item_bean, warehouse_fieldname)
+	
+	if meta.get_field("currency"):
+		out.base_ref_rate = out.basic_rate = out.ref_rate = out.export_rate = 0.0
+		
+		if args.selling_price_list and args.price_list_currency:
+			out.update(_get_price_list_rate(args, item_bean, meta))
+		
+	out.update(_get_item_discount(out.item_group, args.customer))
+	
+	if out.get(warehouse_fieldname):
+		out.update(get_available_qty(args.item_code, out.get(warehouse_fieldname)))
+	
+	out.customer_item_code = _get_customer_item_code(args, item_bean)
+	
+	if cint(args.is_pos):
+		pos_settings = get_pos_settings(args.company)
+		if pos_settings:
+			out.update(apply_pos_settings(pos_settings, out))
+		
+	if args.doctype in ("Sales Invoice", "Delivery Note"):
+		if item_bean.doc.has_serial_no == "Yes" and not args.serial_no:
+			out.serial_no = _get_serial_nos_by_fifo(args, item_bean)
+		
+	return out
+
+def _get_serial_nos_by_fifo(args, item_bean):
+	return "\n".join(webnotes.conn.sql_list("""select name from `tabSerial No` 
+		where item_code=%(item_code)s and warehouse=%(warehouse)s and status='Available' 
+		order by timestamp(purchase_date, purchase_time) asc limit %(qty)s""", {
+			"item_code": args.item_code,
+			"warehouse": args.warehouse,
+			"qty": cint(args.qty)
+		}))
+
+def _get_item_code(barcode=None, serial_no=None):
+	if barcode:
+		input_type = "Barcode"
+		item_code = webnotes.conn.sql_list("""select name from `tabItem` where barcode=%s""", barcode)
+	elif serial_no:
+		input_type = "Serial No"
+		item_code = webnotes.conn.sql_list("""select item_code from `tabSerial No` 
+			where name=%s""", serial_no)
+			
+	if not item_code:
+		msgprint(_("No Item found with ") + input_type + ": %s" % (barcode or serial_no), raise_exception=True)
+	
+	return item_code[0]
+	
+def _validate_item_details(args, item):
+	from erpnext.utilities.transaction_base import validate_item_fetch
+	validate_item_fetch(args, item)
+	
+	# validate if sales item or service item
+	if args.order_type == "Maintenance":
+		if item.is_service_item != "Yes":
+			msgprint(_("Item") + (" %s: " % item.name) + 
+				_("not a service item.") +
+				_("Please select a service item or change the order type to Sales."), 
+				raise_exception=True)
+		
+	elif item.is_sales_item != "Yes":
+		msgprint(_("Item") + (" %s: " % item.name) + _("not a sales item"),
+			raise_exception=True)
+			
+def _get_basic_details(args, item_bean, warehouse_fieldname):
+	item = item_bean.doc
+	
+	out = webnotes._dict({
+			"item_code": item.name,
+			"description": item.description_html or item.description,
+			warehouse_fieldname: item.default_warehouse or args.get(warehouse_fieldname),
+			"income_account": item.default_income_account or args.income_account \
+				or webnotes.conn.get_value("Company", args.company, "default_income_account"),
+			"expense_account": item.purchase_account or args.expense_account \
+				or webnotes.conn.get_value("Company", args.company, "default_expense_account"),
+			"cost_center": item.default_sales_cost_center or args.cost_center,
+			"qty": 1.0,
+			"export_amount": 0.0,
+			"amount": 0.0,
+			"batch_no": None,
+			"item_tax_rate": json.dumps(dict(([d.tax_type, d.tax_rate] for d in 
+				item_bean.doclist.get({"parentfield": "item_tax"})))),
+		})
+	
+	for fieldname in ("item_name", "item_group", "barcode", "brand", "stock_uom"):
+		out[fieldname] = item.fields.get(fieldname)
+			
+	return out
+	
+def _get_price_list_rate(args, item_bean, meta):
+	ref_rate = webnotes.conn.sql("""select ref_rate from `tabItem Price` 
+		where price_list=%s and item_code=%s and buying_or_selling='Selling'""", 
+		(args.selling_price_list, args.item_code), as_dict=1)
+
+	if not ref_rate:
+		return {}
+	
+	# found price list rate - now we can validate
+	from erpnext.utilities.transaction_base import validate_currency
+	validate_currency(args, item_bean.doc, meta)
+	
+	return {"ref_rate": flt(ref_rate[0].ref_rate) * flt(args.plc_conversion_rate) / flt(args.conversion_rate)}
+	
+def _get_item_discount(item_group, customer):
+	parent_item_groups = [x[0] for x in webnotes.conn.sql("""SELECT parent.name 
+		FROM `tabItem Group` AS node, `tabItem Group` AS parent 
+		WHERE parent.lft <= node.lft and parent.rgt >= node.rgt and node.name = %s
+		GROUP BY parent.name 
+		ORDER BY parent.lft desc""", (item_group,))]
+		
+	discount = 0
+	for d in parent_item_groups:
+		res = webnotes.conn.sql("""select discount, name from `tabCustomer Discount` 
+			where parent = %s and item_group = %s""", (customer, d))
+		if res:
+			discount = flt(res[0][0])
+			break
+			
+	return {"adj_rate": discount}
+
+@webnotes.whitelist()
+def get_available_qty(item_code, warehouse):
+	return webnotes.conn.get_value("Bin", {"item_code": item_code, "warehouse": warehouse}, 
+		["projected_qty", "actual_qty"], as_dict=True) or {}
+		
+def _get_customer_item_code(args, item_bean):
+	customer_item_code = item_bean.doclist.get({"parentfield": "item_customer_details",
+		"customer_name": args.customer})
+	
+	return customer_item_code and customer_item_code[0].ref_code or None
+	
+def get_pos_settings(company):
+	pos_settings = webnotes.conn.sql("""select * from `tabPOS Setting` where user = %s 
+		and company = %s""", (webnotes.session['user'], company), as_dict=1)
+	
+	if not pos_settings:
+		pos_settings = webnotes.conn.sql("""select * from `tabPOS Setting` 
+			where ifnull(user,'') = '' and company = %s""", company, as_dict=1)
+			
+	return pos_settings and pos_settings[0] or None
+	
+def apply_pos_settings(pos_settings, opts):
+	out = {}
+	
+	for fieldname in ("income_account", "cost_center", "warehouse", "expense_account"):
+		if not opts.get(fieldname):
+			out[fieldname] = pos_settings.get(fieldname)
+			
+	if out.get("warehouse"):
+		out["actual_qty"] = get_available_qty(opts.item_code, out.get("warehouse")).get("actual_qty")
+	
+	return out
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