class Basket:
def __init__(self, catalogue_json_file: str, offer_types_json_file: str,
product_offers_json_file: str):
self.catalogue = Catalogue(catalogue_json_file)
self.product_offers = ProductOffers(offer_types_json_file,
product_offers_json_file)
self.products = {}
self.sub_total, self.discount, self.total = 0.0, 0.0, 0.0
def update(self, product_name: str, count: int = 1):
# First make sure that the product is in the catalogue
if not self.catalogue.is_valid_product(product_name):
raise Exception("Invalid Product")
# Update the number of items
if product_name not in self.products and count < 1:
return
self.products[product_name] = count + self.products.get(
product_name, 0)
if self.products[product_name] < 1:
del self.products[product_name]
# Now recalculate the basket price
self.calculate_price()
def calculate_price(self):
sub_total = 0.0
discount = 0.0
for product, product_count in self.products.items():
product_base_price = self.catalogue.get_base_price(product)
sub_sub_total = product_count * product_base_price
sub_discount = 0.0
# check if there are any offers for this product
offer = self.product_offers.get_offer_for_product(product)
print(product, offer)
if offer:
if 'buy' in offer:
buy = offer['buy']
free = offer.get('free', 0)
total_offer_qty = buy + free
offer_count = product_count // total_offer_qty if product_count >= total_offer_qty else 0
discount += offer_count * free * product_base_price
elif 'discount' in offer:
discount_pct = offer['discount']
sub_discount = discount_pct * sub_sub_total / 100
sub_total += sub_sub_total
discount += sub_discount
self.sub_total = round(sub_total, 2)
self.discount = round(discount, 2)
self.total = round(sub_total - discount, 2)
def empty(self):
self.products = {}
self.sub_total, self.discount, self.total = 0.0, 0.0, 0.0
def pricer(self) -> dict:
return {
"sub-total": self.sub_total,
"discount": self.discount,
"total": self.total
}
def test_catalogue():
catalogue = Catalogue("sample_catalogue.json")
assert catalogue.get_base_price("Sardines") == 1.89
assert catalogue.get_base_price("Tomatoes") == 0.0