import { ReadonlyURLSearchParams } from "next/navigation";

export const createUrl = (pathname: string, params: URLSearchParams | ReadonlyURLSearchParams) => {
  const paramsString = params.toString();
  const queryString = `${paramsString.length ? "?" : ""}${paramsString}`;

  return `${pathname}${queryString}`;
};

export const ensureStartsWith = (stringToCheck: string, startsWith: string) =>
  stringToCheck.startsWith(startsWith) ? stringToCheck : `${startsWith}${stringToCheck}`;

export const validateEnvironmentVariables = () => {
  const requiredEnvironmentVariables = ["SHOPIFY_STORE_DOMAIN", "SHOPIFY_STOREFRONT_ACCESS_TOKEN"];
  const missingEnvironmentVariables = [] as string[];

  requiredEnvironmentVariables.forEach((envVar) => {
    if (!process.env[envVar]) {
      missingEnvironmentVariables.push(envVar);
    }
  });

  if (missingEnvironmentVariables.length) {
    throw new Error(
      `The following environment variables are missing. Your site will not work without them. Read more: https://vercel.com/docs/integrations/shopify#configure-environment-variables\n\n${missingEnvironmentVariables.join(
        "\n"
      )}\n`
    );
  }

  if (
    process.env.SHOPIFY_STORE_DOMAIN?.includes("[") ||
    process.env.SHOPIFY_STORE_DOMAIN?.includes("]")
  ) {
    throw new Error(
      "Your `SHOPIFY_STORE_DOMAIN` environment variable includes brackets (ie. `[` and / or `]`). Your site will not work with them there. Please remove them."
    );
  }
};