/**
 * A wrapper for videojs.xhr that tracks bandwidth.
 */
import {xhr as videojsXHR, mergeOptions} from 'video.js';

const xhrFactory = function() {
  const xhr = function XhrFunction(options, callback) {
    // Add a default timeout for all hls requests
    options = mergeOptions({
      timeout: 45e3
    }, options);

    // Allow an optional user-specified function to modify the option
    // object before we construct the xhr request
    if (XhrFunction.beforeRequest &&
        typeof XhrFunction.beforeRequest === 'function') {
      let newOptions = XhrFunction.beforeRequest(options);

      if (newOptions) {
        options = newOptions;
      }
    }

    let request = videojsXHR(options, function(error, response) {
      if (!error && request.response) {
        request.responseTime = (new Date()).getTime();
        request.roundTripTime = request.responseTime - request.requestTime;
        request.bytesReceived = request.response.byteLength || request.response.length;
        if (!request.bandwidth) {
          request.bandwidth =
            Math.floor((request.bytesReceived / request.roundTripTime) * 8 * 1000);
        }
      }

      // videojs.xhr now uses a specific code
      // on the error object to signal that a request has
      // timed out errors of setting a boolean on the request object
      if (error || request.timedout) {
        request.timedout = request.timedout || (error.code === 'ETIMEDOUT');
      } else {
        request.timedout = false;
      }

      // videojs.xhr no longer considers status codes outside of 200 and 0
      // (for file uris) to be errors, but the old XHR did, so emulate that
      // behavior. Status 206 may be used in response to byterange requests.
      if (!error &&
          response.statusCode !== 200 &&
          response.statusCode !== 206 &&
          response.statusCode !== 0) {
        error = new Error('XHR Failed with a response of: ' +
                          (request && (request.response || request.responseText)));
      }

      callback(error, request);
    });

    request.requestTime = (new Date()).getTime();
    return request;
  };

  return xhr;
};

export default xhrFactory;