Apply Discount Code

import dash from "@/lib/dash"

// Apply discount
const { message, cart } = await dash.cart.applyDiscount("SAVE20")
// cart.discount_code = "SAVE20"
// cart.discount_amount = "15.00"

// Remove discount
const result = await dash.cart.removeDiscount()

// This doesn't apply the code — just checks it
const response = await fetch("/storefront/discount/validate", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "X-API-Key": apiKey,
  },
  body: JSON.stringify({
    code: "SAVE20",
    subtotal: "99.99",
  }),
})

const result = await response.json()
// result = {
//   valid: true,
//   discount_amount: "15.00",
//   is_percentage: true,
//   rate: "20",
//   code: "SAVE20"
// }

"use client"
import { useState } from "react"
import dash from "@/lib/dash"

export function DiscountCodeInput({ onApplied }) {
  const [code, setCode] = useState("")
  const [error, setError] = useState("")

  async function handleApply() {
    try {
      setError("")
      const { cart } = await dash.cart.applyDiscount(code)
      onApplied(cart)
    } catch (err) {
      setError(err.message) // "Invalid code" or "Code expired"
    }
  }

  return (
    <div>
      <input value={code} onChange={e => setCode(e.target.value)}
             placeholder="Discount code" />
      <button onClick={handleApply}>Apply</button>
      {error && <p className="text-red-500">{error}</p>}
    </div>
  )
}

# Apply discount
POST /storefront/cart/{cart_id}/apply-discount
Content-Type: application/json
X-API-Key: pk_live_your_key

{ "code": "SAVE20" }

# Remove discount
POST /storefront/cart/{cart_id}/remove-discount
X-API-Key: pk_live_your_key

# Validate without applying
POST /storefront/discount/validate
Content-Type: application/json
X-API-Key: pk_live_your_key

{ "code": "SAVE20", "subtotal": "99.99" }