const aws4 = require('aws4');
const { URL } = require('url');
const fetch = require('./fetch');
const resolveCname = require('./resolveCname');

module.exports = async (url, options = {}, credentials = {}) => {
  const parsedURL = new URL(url);

  // Ensure we sign the actual service URL and not a load balancer URL
  const hostname = await resolveCname(parsedURL.host);

  const signedOptions = {
    method: options.method,
    host: hostname,
    path: parsedURL.pathname + parsedURL.search,
    body: options.body,
    headers: options.headers
  };

  aws4.sign(signedOptions, {
    accessKeyId: credentials.awsAccessKey,
    secretAccessKey: credentials.awsSecretAccessKey
  });

  options.headers = signedOptions.headers;

  return fetch(`https://${signedOptions.host}${signedOptions.path}`, options);
};