# Copyright (c) 2013, Frappe Technologies Pvt. Ltd. and contributors
# For license information, please see license.txt

from __future__ import unicode_literals

import frappe
from frappe import _
from frappe.utils import cint, getdate


def execute(filters=None):
	if not filters: filters = {}

	float_precision = cint(frappe.db.get_default("float_precision")) or 3

	columns = get_columns(filters)
	item_map = get_item_details(filters)
	iwb_map = get_item_warehouse_batch_map(filters, float_precision)

	data = []
	for item in sorted(iwb_map):
		for wh in sorted(iwb_map[item]):
			for batch in sorted(iwb_map[item][wh]):
				qty_dict = iwb_map[item][wh][batch]

				data.append([item, item_map[item]["item_name"], item_map[item]["description"], wh, batch,
					frappe.db.get_value('Batch', batch, 'expiry_date'), qty_dict.expiry_status
				])


	return columns, data

def get_columns(filters):
	"""return columns based on filters"""

	columns = [_("Item") + ":Link/Item:100"] + [_("Item Name") + "::150"] + [_("Description") + "::150"] + \
	[_("Warehouse") + ":Link/Warehouse:100"] + [_("Batch") + ":Link/Batch:100"] + [_("Expires On") + ":Date:90"] + \
	[_("Expiry (In Days)") + ":Int:120"]

	return columns

def get_conditions(filters):
	conditions = ""
	if not filters.get("from_date"):
		frappe.throw(_("'From Date' is required"))

	if filters.get("to_date"):
		conditions += " and posting_date <= '%s'" % filters["to_date"]
	else:
		frappe.throw(_("'To Date' is required"))

	return conditions

def get_stock_ledger_entries(filters):
	conditions = get_conditions(filters)
	return frappe.db.sql("""select item_code, batch_no, warehouse,
		posting_date, actual_qty
		from `tabStock Ledger Entry`
		where docstatus < 2 and ifnull(batch_no, '') != '' %s order by item_code, warehouse""" %
		conditions, as_dict=1)

def get_item_warehouse_batch_map(filters, float_precision):
	sle = get_stock_ledger_entries(filters)
	iwb_map = {}

	from_date = getdate(filters["from_date"])
	to_date = getdate(filters["to_date"])

	for d in sle:
		iwb_map.setdefault(d.item_code, {}).setdefault(d.warehouse, {})\
			.setdefault(d.batch_no, frappe._dict({
				"expires_on": None, "expiry_status": None}))

		qty_dict = iwb_map[d.item_code][d.warehouse][d.batch_no]

		expiry_date_unicode = frappe.db.get_value('Batch', d.batch_no, 'expiry_date')
		qty_dict.expires_on = expiry_date_unicode

		exp_date = frappe.utils.data.getdate(expiry_date_unicode)
		qty_dict.expires_on = exp_date

		expires_in_days = (exp_date - frappe.utils.datetime.date.today()).days

		if expires_in_days > 0:
			qty_dict.expiry_status = expires_in_days
		else:
			qty_dict.expiry_status = 0

	return iwb_map

def get_item_details(filters):
	item_map = {}
	for d in frappe.db.sql("select name, item_name, description from tabItem", as_dict=1):
		item_map.setdefault(d.name, d)

	return item_map
