// ============================================================================
// 084 — Invoice Generator
// ============================================================================
// Create invoices with line items and compute totals.
//
// Run:   soma run 084_invoice.cell demo
// Expect:
//   === INVOICE ===
//   Customer: Acme Corp
//   Items:
//     Widget x10 @ $9.99 = $99.90
//     Gadget x5 @ $19.99 = $99.95
//     Service x1 @ $150.00 = $150.00
//   Subtotal: $349.85
//   Tax (10%): $34.985
//   Total: $384.835

cell Invoice {

    on demo() {
        let customer = "Acme Corp"
        let items = list(
            map("name", "Widget", "qty", 10, "price", 9.99),
            map("name", "Gadget", "qty", 5, "price", 19.99),
            map("name", "Service", "qty", 1, "price", 150.00)
        )

        let tax_rate = 0.10

        print("=== INVOICE ===")
        print("Customer: {customer}")
        print("Items:")

        let subtotal = 0.0
        for item in items {
            let line_total = to_float(item.qty) * item.price
            subtotal = subtotal + line_total
            print("  {item.name} x{item.qty} @ ${item.price} = ${line_total}")
        }

        let tax = subtotal * tax_rate
        let total = subtotal + tax

        print("Subtotal: ${subtotal}")
        print("Tax (10%): ${tax}")
        print("Total: ${total}")

        return "done"
    }
}