| |
| |
| |
| class Cart { |
| constructor() { |
| this.items = new Map(); |
| this.coupon = null; |
| } |
|
|
| add(sku, name, unitPrice, qty = 1) { |
| if (!Number.isInteger(unitPrice) || unitPrice < 0) throw new TypeError('unitPrice negatif olmayan tam sayı olmalı'); |
| if (!Number.isInteger(qty) || qty < 1) throw new RangeError('qty en az 1 olmalı'); |
| const cur = this.items.get(sku); |
| if (cur) cur.qty += qty; |
| else this.items.set(sku, { name, unitPrice, qty }); |
| return this; |
| } |
|
|
| remove(sku, qty = Infinity) { |
| const cur = this.items.get(sku); |
| if (!cur) return false; |
| if (qty >= cur.qty) this.items.delete(sku); |
| else cur.qty -= qty; |
| return true; |
| } |
|
|
| subtotal() { |
| let sum = 0; |
| for (const { unitPrice, qty } of this.items.values()) sum += unitPrice * qty; |
| return sum; |
| } |
|
|
| applyCoupon(code) { |
| const coupons = { YUZDE10: { type: 'percent', value: 10 }, INDIRIM50: { type: 'fixed', value: 5000 } }; |
| const c = coupons[String(code).toUpperCase()]; |
| if (!c) throw new Error('Geçersiz kupon'); |
| this.coupon = c; |
| } |
|
|
| discount() { |
| const sub = this.subtotal(); |
| if (!this.coupon) return 0; |
| if (this.coupon.type === 'percent') return Math.round((sub * this.coupon.value) / 100); |
| return Math.min(this.coupon.value, sub); |
| } |
|
|
| shipping() { |
| const afterDiscount = this.subtotal() - this.discount(); |
| if (this.items.size === 0) return 0; |
| return afterDiscount >= 50000 ? 0 : 2999; |
| } |
|
|
| total() { |
| return this.subtotal() - this.discount() + this.shipping(); |
| } |
| } |
|
|
| module.exports = { Cart }; |
|
|
