A small electronics company has hired you to write an application to manage their inventory. The company requested a role-based access control (RBAC) to increase the security around using the new application. The company also requested that the application menu must be flexible enough to allow adding new menu items to the menu with minimal changes. This includes re-ordering the menu items and making changes to the description of a menu item without having to change the code.
The company has suggested to start the application by prompting the user for a username and password to authenticate the user. There are two types of users at this company, managers and employees. If managers log on to the application, they will see all options on the menu list. If employees log on to the application, they will see a limited set of options on the menu list. User information is stored in Users.dat file, which may or may not exist at the start of the program. A super user “admin” with password “admin” has already been hardcoded in the program to allow for the initial setup and the creation of other users. The Users.dat file contains the FirstName, LastName, Username (case insensitive), HashedPassword and a flag to indicate whether a user is a manager or not. The file is comma separated and it is formatted as follows:
Joe, Last, jlast, 58c536ed8facc2c2a293a18a48e3e120, true Sam, sone, samsone, 2c2a293a18a48e3e12058c536ed8facc, false Jane, Best, jbest, 293a18a48e3e12052058c536ed8facc2c, false
Note: Ensure that the ‘AddUser’ function does not add duplicate values, and the ‘ChangePassword’ function does not change password if username/password is entered incorrectly. If adding a new user or changing the password is successful, return true, or else return false.
The menu of the application is dynamically loaded and displayed to the user only after the user successfully logs on. The menu items will be loaded from file “MenuList.dat”, which may or may not exist at the start of the application. If the file doesn’t exist, the application should show at least an Exit menu item as default. The file will contain all menu items details, including the name of the command that will be executed when the menu item is selected. If a menu item is marked as restricted (Boolean flag), only managers can see that item. The file contains the following comma separated fields, Description, a Boolean flag to indicate if the option is restricted to managers only, and the name of the menu command that will be executed when the option is chosen. The order and option number of a menu item may change depending on how they are listed in the file. The Exit option will always be listed last and it will not be in the file.
Below is a sample of how the MenuList.dat file looks like:
Add User, true, AddUserCommand Delete User, true, DeleteUserCommand Change Password, false, ChangePasswordCommand Add New Product, true, AddProductCommand
Note: The command name of each menu item must match the name of the class that you will create in the code (See AddProductCommand class in the code for example).
The inventory consists of multiple products of type Product stored in class ProductCatalog. The ProductCatalog is responsible of all inventory operations that add, remove, find and update a product. When printing a product information, the product retail price should be calculated and displayed as well. Retail price = (cost + (margin * cost/100)). A list of functions has been added to this class in the provided code template. You must implement all listed functions. The inventory products will be saved in file Inventory.dat, which may or may not exist when the program first starts. The file will contain the product unique id (int), product name (string), cost (double), quantity (int) and margin (int, integer that represents margin percentage).
The Inventory.dat file is comma separated and formatted as follows:
3424, Smart Watch, 20.45, 23, 80 65454, Flat Screen TV, 465.98, 15, 35 435, Computer Monitor, 123.54, 84, 43
Enter username: some username Enter password: some password //Repeat prompts until user is authenticated OR show error and option to exit. Invalid username or password! Press enter to continue or “Exit” to exit: Enter username: some username Enter password: some password Welcome Firstname LastName! Inventory Management System Menu //This is the header of the MenuList // The order and option number of a menu item may change depending on how they are listed in the MenuList.dat file. The Exit option will always be listed last and it will not be in the MenuList.dat file. 1- Add user 2- Remove user 3- Change password 4- Add new product 5- Update product information 6- Delete product 7- Display product information 8- Display inventory 9- Exit Enter your selection: 7 Enter product name: sMaRt wAtCh Id Name Cost Quantity Retail ---------------------------------------------------- 3424 Smart Watch $20.45 23 $36.81 //Repeat the menu after each command is executed
A unit test method is required to test each of the methods listed below. These methods will be used by the unit testing framework to test the accuracy of your code.