middleware.js

import { cookies } from "next/headers";
import { NextResponse } from "next/server";
import { createI18nMiddleware } from "next-international/middleware";

import { getCartMiddleware } from "@/lib/cart";

// Define the cart validation middleware
async function cartMiddleware(request) {
  // 1. Check if the cookies has the cart id
  const storeCookies = await cookies();
  const hasCartId = storeCookies.has("cartId");

  if (!hasCartId) {
    return NextResponse.redirect(new URL("/", request.url));
  }

  // 2. Get the cart id
  const cartId = storeCookies.get("cartId").value;

  // 3. Fetch cart data
  const { data, errors } = await getCartMiddleware(cartId);

  // 4. Check if there errors
  if (errors) {
    return NextResponse.redirect(new URL("/", request.url));
  }

  // 5. Check if the cart is NOT empty
  if (data.cart.lines.nodes.length === 0) {
    return NextResponse.redirect(new URL("/", request.url));
  }

  return NextResponse.next();
}

// Create the I18n middleware
const I18nMiddleware = createI18nMiddleware({
  locales: ["en", "fr"],
  defaultLocale: "en",
});

// Combined middleware function
export async function middleware(request) {
  const pathname = request.nextUrl.pathname;

  // Check if the path starts with a locale
  const localePattern = /^\/(en|fr|ar)(\/|$)/;
  if (!localePattern.test(pathname) && pathname.startsWith("/checkout")) {
    // Redirect to default locale (e.g., /en/checkout)
    return NextResponse.redirect(new URL(`/en${pathname}`, request.url));
  }

  // Apply the internationalization middleware
  const i18nResponse = I18nMiddleware(request);

  // Check if it's a checkout page
  const isCheckoutPage = pathname.endsWith("/checkout");

  // Apply cart validation only for checkout pages after i18n processing
  if (isCheckoutPage) {
    return cartMiddleware(request);
  }

  return i18nResponse;
}

export const config = {
  // Match both internationalized pathnames and checkout paths, excluding static files and API routes
  matcher: ["/((?!api|static|.*\\..*|_next|favicon.ico|robots.txt).*)"],
};