# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
# License: GNU General Public License v3. See license.txt

from __future__ import unicode_literals
import frappe, json
from frappe.utils.nestedset import get_root_of
from frappe.utils import cint
from erpnext.accounts.doctype.pos_profile.pos_profile import get_item_groups

from six import string_types

@frappe.whitelist()
def get_items(start, page_length, price_list, item_group, search_value="", pos_profile=None):
	serial_no = ""
	batch_no = ""
	barcode = ""

	item_code = search_value
	if not frappe.db.exists('Item Group', item_group):
		item_group = get_root_of('Item Group')

	if search_value:
		# search serial no
		serial_no_data = frappe.db.get_value('Serial No', search_value, ['name', 'item_code'])
		if serial_no_data:
			serial_no, item_code = serial_no_data

		if not serial_no:
			batch_no_data = frappe.db.get_value('Batch', search_value, ['name', 'item'])
			if batch_no_data:
				batch_no, item_code = batch_no_data

		if not serial_no and not batch_no:
			barcode_data = frappe.db.get_value('Item Barcode', {'barcode': search_value}, ['parent', 'barcode'])
			if barcode_data:
				item_code, barcode = barcode_data

	item_code, condition = get_conditions(item_code, serial_no, batch_no, barcode)

	if pos_profile:
		condition += get_item_group_condition(pos_profile)

	lft, rgt = frappe.db.get_value('Item Group', item_group, ['lft', 'rgt'])
	# locate function is used to sort by closest match from the beginning of the value
	res = frappe.db.sql("""select i.name as item_code, i.item_name, i.image as item_image,
		i.is_stock_item, item_det.price_list_rate, item_det.currency
		from `tabItem` i LEFT JOIN
			(select item_code, price_list_rate, currency from
				`tabItem Price`	where price_list=%(price_list)s) item_det
		ON
			(item_det.item_code=i.name or item_det.item_code=i.variant_of)
		where
			i.disabled = 0 and i.has_variants = 0 and i.is_sales_item = 1
			and i.item_group in (select name from `tabItem Group` where lft >= {lft} and rgt <= {rgt})
			and {condition}
		limit {start}, {page_length}""".format(start=start,
			page_length=page_length, lft=lft, rgt=rgt, condition=condition),
		{
			'item_code': item_code,
			'price_list': price_list
		} , as_dict=1)

	res = {
		'items': res
	}

	if serial_no:
		res.update({
			'serial_no': serial_no
		})

	if batch_no:
		res.update({
			'batch_no': batch_no
		})

	if barcode:
		res.update({
			'barcode': barcode
		})

	return res

def get_conditions(item_code, serial_no, batch_no, barcode):
	if serial_no or batch_no or barcode:
		return frappe.db.escape(item_code), "i.name = %(item_code)s"

	condition = """(i.name like %(item_code)s
			or i.item_name like %(item_code)s)"""

	return '%%%s%%'%(frappe.db.escape(item_code)), condition

def get_item_group_condition(pos_profile):
	cond = "and 1=1"
	item_groups = get_item_groups(pos_profile)
	if item_groups:
		cond = "and i.item_group in (%s)"%(', '.join(['%s']*len(item_groups)))

	return cond % tuple(item_groups)

def item_group_query(doctype, txt, searchfield, start, page_len, filters):
	item_groups = []
	cond = "1=1"
	pos_profile= filters.get('pos_profile')

	if pos_profile:
		item_groups = get_item_groups(pos_profile)

		if item_groups:
			cond = "name in (%s)"%(', '.join(['%s']*len(item_groups)))
			cond = cond % tuple(item_groups)

	return frappe.db.sql(""" select distinct name from `tabItem Group`
			where {condition} and (name like %(txt)s) limit {start}, {page_len}"""
		.format(condition = cond, start=start, page_len= page_len),
			{'txt': '%%%s%%' % txt})