Customer

Smart Retail Assistant (SRA)

Cart System

Inventory System

Payment Gateway

Order Management System (OMS)

addToCart(productID, quantity)

saveCart(customerID, productID, quantity)

Clicks "Proceed to Checkout"

getCartDetails(customerID)

CartDetails (productList, quantities, subtotal)

Confirms Order

checkStockAvailability(CartDetails)

[Stock is Available]

stockAvailable: true

processPayment(amount=subtotal, paymentDetails)

[Payment is Successful]

paymentConfirmation {transactionID, status: "SUCCESS", timestamp}

generateOrderRecord(CartDetails, paymentConfirmation)

submitOrder(OrderRecord)

assignOrderID(), setStatus("Processing")

decrementStock(OrderDetails)

orderConfirmation (OrderID, summary, status)

triggerConfirmationEmail(OrderID, summary)

Display Confirmation Page (OrderID, summary)

[Payment Fails]

paymentConfirmation {status: "FAILURE"}

showPaymentError()

[Stock is Unavailable]

stockAvailable: false, unavailableItems

showStockError(unavailableItems)