@lacspace/coupon
Discount & coupon engine — percent, fixed, free-shipping, BOGO and tiered codes, with validity windows, total/per-user limits, first-order and product/category scope, a currency guard, safe coupon stacking and CSPRNG code generation. Integer minor units, no float drift. Zero-dependency, isomorphic.
npm i @lacspace/couponUsage
import { validateCoupon, applyCoupon } from "@lacspace/coupon";
const coupon = { code: "DASHAIN", type: "percent", value: 15, minSubtotal: 200000, cap: 50000 };
const check = validateCoupon(coupon, { subtotal: 350000, now: Date.now() });
if (check.ok) {
const { discount, total } = applyCoupon(coupon, 350000); // discount capped at 50000
}Exports 2
validateCouponapplyCouponKeywords
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