/**
 * This function will fetch a url to follow all redirects and compare the base url
 * with the RegEx to validate false and true positives.
 *
 * @param message The message that originally triggered the provided RegEx
 * @param banRegEx RegEx to check against
 * @returns @type boolean
 */

const linkChecker = async (message: string, banRegEx: RegExp) => {
  const detectedLinks = message.split(" ").map(subStr => {
    if (banRegEx.test(subStr)) {
      return subStr;
    }
  });

  if (!detectedLinks || detectedLinks.length === 0) {
    return false;
  }

  const resolvedURLs = detectedLinks.map(async string => {
    if (string === undefined) {
      return false;
    }

    const url =
      string.startsWith("http://") || string.startsWith("https://")
        ? string
        : `https://${string}`;

    const res = await fetch(url, {
      headers: {
        "user-agent":
          "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0"
      }
    });

    const resolvedURL = new URL(res.url);
    const baseURL = resolvedURL.hostname.split(".").slice(-2).join(".");

    if (/^x\.com/i.test(baseURL)) {
      return true;
    }
  });

  return (await Promise.all(resolvedURLs)).includes(true);
};

export default linkChecker;