You are tasked with designing a system for an online book ordering and Inventory management system for a bookstore. The system should allow customers to browse the available books, place orders, and for the bookstore staff to manage the inventory efficiently.

Requirements:

Customer Interaction:

Customers should be able to browse the catalogue of books online. Customers should be able to search for books by title, author, or genre. The system should allow customers to add books to their shopping cart. Customers should be able to proceed to checkout, providing shipping details and confirming the order.

Order Processing:

Upon confirmation of an order, the system should deduct the purchased books from the inventory. The system should generate an order confirmation for the customer.

In case a book is out of stock, the system should notify the customer and prevent the order from being processed.

Inventory Management:

Bookstore staff should be able to add new books to the inventory. Staff should be able to update the quantity of available books.

The system should notify staff when the stock of a particular book falls below a predefined threshold.

User Authentication and Authorization:

Customers should be able to create accounts and log in$.$

Bookstore staff should have dlfferent roles $($e$.$g$.,$ regular staff, manager$)$ with varying levels of access to the system.

Only authenticated staff should be able to manage the inventory.

Create a Data Flow Diagram $($DFD$)$ and a Use Case Diagram using UML for the described system. Identify major processes, data stores, data flows, external entities, and use cases.