You work for a company called "Skin Deep" on their online beauty product shopping application. The company has a chain of physical Stores around the country, and also has this online application, so that customers can order products to collect in store, or for home delivery.
You are working on a part of the code, that handles updating the online shopping Cart, when a customer switches the Store they are shopping at.
You have just joined the team, and your first task is to add a new kind of delivery - by Drone.
There is more information about the business rules for the existing features and new feature in the text below.
There is more information about what each piece of the code does, in javadoc comments. Note, all the classes that implement "ModelObject" are generated from a database schema and you are not allowed to edit them.
There is a new delivery method being trialled at certain stores - delivery by Drone. You are working on adding support for this delivery type to the OnlineShopping class, in the 'switchStore' method.
When switching stores, if both current and new store support drone delivery, there is no change to the delivery information. If "DRONE" delivery is selected in the delivery information type and the new store does not support it, change the delivery type to "PICKUP". If the old store does not support Drone delivery, but the new one does, and the delivery information is "HOME_DELIVERY", and the weight of the items is under 5kg, then change the delivery information type to "DRONE".
If the new store is null (ie we have selected the central warehouse) then Drone delivery is not available. The delivery information type should be changed to "SHIPPING".