@videojs/http-streaming/dist/videojs-http-streaming.es.js

Play back HLS and DASH with Video.js, even where it's not natively supported

/**
 * @videojs/http-streaming
 * @version 1.13.3
 * @copyright 2020 Brightcove, Inc
 * @license Apache-2.0
 */
import URLToolkit from 'url-toolkit';
import window$1 from 'global/window';
import videojs from 'video.js';
import { Parser } from 'm3u8-parser';
import document from 'global/document';
import { parse, parseUTCTiming } from 'mpd-parser';
import mp4Inspector from 'mux.js/lib/tools/mp4-inspector';
import mp4probe from 'mux.js/lib/mp4/probe';
import CaptionParser from 'mux.js/lib/mp4/caption-parser';
import tsInspector from 'mux.js/lib/tools/ts-inspector.js';
import { Decrypter, AsyncStream, decrypt } from 'aes-decrypter';

/**
 * @file resolve-url.js - Handling how URLs are resolved and manipulated
 */

var resolveUrl = function resolveUrl(baseURL, relativeURL) {
  // return early if we don't need to resolve
  if (/^[a-z]+:/i.test(relativeURL)) {
    return relativeURL;
  }

  // if the base URL is relative then combine with the current location
  if (!/\/\//i.test(baseURL)) {
    baseURL = URLToolkit.buildAbsoluteURL(window$1.location.href, baseURL);
  }

  return URLToolkit.buildAbsoluteURL(baseURL, relativeURL);
};

/**
 * Checks whether xhr request was redirected and returns correct url depending
 * on `handleManifestRedirects` option
 *
 * @api private
 *
 * @param  {String} url - an url being requested
 * @param  {XMLHttpRequest} req - xhr request result
 *
 * @return {String}
 */
var resolveManifestRedirect = function resolveManifestRedirect(handleManifestRedirect, url, req) {
  // To understand how the responseURL below is set and generated:
  // - https://fetch.spec.whatwg.org/#concept-response-url
  // - https://fetch.spec.whatwg.org/#atomic-http-redirect-handling
  if (handleManifestRedirect && req.responseURL && url !== req.responseURL) {
    return req.responseURL;
  }

  return url;
};

var classCallCheck = function (instance, Constructor) {
  if (!(instance instanceof Constructor)) {
    throw new TypeError("Cannot call a class as a function");
  }
};

var createClass = function () {
  function defineProperties(target, props) {
    for (var i = 0; i < props.length; i++) {
      var descriptor = props[i];
      descriptor.enumerable = descriptor.enumerable || false;
      descriptor.configurable = true;
      if ("value" in descriptor) descriptor.writable = true;
      Object.defineProperty(target, descriptor.key, descriptor);
    }
  }

  return function (Constructor, protoProps, staticProps) {
    if (protoProps) defineProperties(Constructor.prototype, protoProps);
    if (staticProps) defineProperties(Constructor, staticProps);
    return Constructor;
  };
}();

var get = function get(object, property, receiver) {
  if (object === null) object = Function.prototype;
  var desc = Object.getOwnPropertyDescriptor(object, property);

  if (desc === undefined) {
    var parent = Object.getPrototypeOf(object);

    if (parent === null) {
      return undefined;
    } else {
      return get(parent, property, receiver);
    }
  } else if ("value" in desc) {
    return desc.value;
  } else {
    var getter = desc.get;

    if (getter === undefined) {
      return undefined;
    }

    return getter.call(receiver);
  }
};

var inherits = function (subClass, superClass) {
  if (typeof superClass !== "function" && superClass !== null) {
    throw new TypeError("Super expression must either be null or a function, not " + typeof superClass);
  }

  subClass.prototype = Object.create(superClass && superClass.prototype, {
    constructor: {
      value: subClass,
      enumerable: false,
      writable: true,
      configurable: true
    }
  });
  if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass;
};

var possibleConstructorReturn = function (self, call) {
  if (!self) {
    throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
  }

  return call && (typeof call === "object" || typeof call === "function") ? call : self;
};

var slicedToArray = function () {
  function sliceIterator(arr, i) {
    var _arr = [];
    var _n = true;
    var _d = false;
    var _e = undefined;

    try {
      for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) {
        _arr.push(_s.value);

        if (i && _arr.length === i) break;
      }
    } catch (err) {
      _d = true;
      _e = err;
    } finally {
      try {
        if (!_n && _i["return"]) _i["return"]();
      } finally {
        if (_d) throw _e;
      }
    }

    return _arr;
  }

  return function (arr, i) {
    if (Array.isArray(arr)) {
      return arr;
    } else if (Symbol.iterator in Object(arr)) {
      return sliceIterator(arr, i);
    } else {
      throw new TypeError("Invalid attempt to destructure non-iterable instance");
    }
  };
}();

/**
 * @file playlist-loader.js
 *
 * A state machine that manages the loading, caching, and updating of
 * M3U8 playlists.
 *
 */

var mergeOptions = videojs.mergeOptions,
    EventTarget = videojs.EventTarget,
    log = videojs.log;

/**
 * Loops through all supported media groups in master and calls the provided
 * callback for each group
 *
 * @param {Object} master
 *        The parsed master manifest object
 * @param {Function} callback
 *        Callback to call for each media group
 */

var forEachMediaGroup = function forEachMediaGroup(master, callback) {
  ['AUDIO', 'SUBTITLES'].forEach(function (mediaType) {
    for (var groupKey in master.mediaGroups[mediaType]) {
      for (var labelKey in master.mediaGroups[mediaType][groupKey]) {
        var mediaProperties = master.mediaGroups[mediaType][groupKey][labelKey];

        callback(mediaProperties, mediaType, groupKey, labelKey);
      }
    }
  });
};

/**
  * Returns a new array of segments that is the result of merging
  * properties from an older list of segments onto an updated
  * list. No properties on the updated playlist will be overridden.
  *
  * @param {Array} original the outdated list of segments
  * @param {Array} update the updated list of segments
  * @param {Number=} offset the index of the first update
  * segment in the original segment list. For non-live playlists,
  * this should always be zero and does not need to be
  * specified. For live playlists, it should be the difference
  * between the media sequence numbers in the original and updated
  * playlists.
  * @return a list of merged segment objects
  */
var updateSegments = function updateSegments(original, update, offset) {
  var result = update.slice();

  offset = offset || 0;
  var length = Math.min(original.length, update.length + offset);

  for (var i = offset; i < length; i++) {
    result[i - offset] = mergeOptions(original[i], result[i - offset]);
  }
  return result;
};

var resolveSegmentUris = function resolveSegmentUris(segment, baseUri) {
  if (!segment.resolvedUri) {
    segment.resolvedUri = resolveUrl(baseUri, segment.uri);
  }
  if (segment.key && !segment.key.resolvedUri) {
    segment.key.resolvedUri = resolveUrl(baseUri, segment.key.uri);
  }
  if (segment.map && !segment.map.resolvedUri) {
    segment.map.resolvedUri = resolveUrl(baseUri, segment.map.uri);
  }
};

/**
  * Returns a new master playlist that is the result of merging an
  * updated media playlist into the original version. If the
  * updated media playlist does not match any of the playlist
  * entries in the original master playlist, null is returned.
  *
  * @param {Object} master a parsed master M3U8 object
  * @param {Object} media a parsed media M3U8 object
  * @return {Object} a new object that represents the original
  * master playlist with the updated media playlist merged in, or
  * null if the merge produced no change.
  */
var updateMaster = function updateMaster(master, media) {
  var result = mergeOptions(master, {});
  var playlist = result.playlists[media.id];

  if (!playlist) {
    return null;
  }

  // consider the playlist unchanged if the number of segments is equal, the media
  // sequence number is unchanged, and this playlist hasn't become the end of the playlist
  if (playlist.segments && media.segments && playlist.segments.length === media.segments.length && playlist.endList === media.endList && playlist.mediaSequence === media.mediaSequence) {
    return null;
  }

  var mergedPlaylist = mergeOptions(playlist, media);

  // if the update could overlap existing segment information, merge the two segment lists
  if (playlist.segments) {
    mergedPlaylist.segments = updateSegments(playlist.segments, media.segments, media.mediaSequence - playlist.mediaSequence);
  }

  // resolve any segment URIs to prevent us from having to do it later
  mergedPlaylist.segments.forEach(function (segment) {
    resolveSegmentUris(segment, mergedPlaylist.resolvedUri);
  });

  // TODO Right now in the playlists array there are two references to each playlist, one
  // that is referenced by index, and one by URI. The index reference may no longer be
  // necessary.
  for (var i = 0; i < result.playlists.length; i++) {
    if (result.playlists[i].id === media.id) {
      result.playlists[i] = mergedPlaylist;
    }
  }
  result.playlists[media.id] = mergedPlaylist;
  // URI reference added for backwards compatibility
  result.playlists[media.uri] = mergedPlaylist;

  return result;
};

var createPlaylistID = function createPlaylistID(index, uri) {
  return index + '-' + uri;
};

var setupMediaPlaylists = function setupMediaPlaylists(master) {
  // setup by-URI lookups and resolve media playlist URIs
  var i = master.playlists.length;

  while (i--) {
    var playlist = master.playlists[i];

    playlist.resolvedUri = resolveUrl(master.uri, playlist.uri);
    playlist.id = createPlaylistID(i, playlist.uri);

    master.playlists[playlist.id] = playlist;
    // URI reference added for backwards compatibility
    master.playlists[playlist.uri] = playlist;

    if (!playlist.attributes) {
      // Although the spec states an #EXT-X-STREAM-INF tag MUST have a
      // BANDWIDTH attribute, we can play the stream without it. This means a poorly
      // formatted master playlist may not have an attribute list. An attributes
      // property is added here to prevent undefined references when we encounter
      // this scenario.
      playlist.attributes = {};

      log.warn('Invalid playlist STREAM-INF detected. Missing BANDWIDTH attribute.');
    }
  }
};

var resolveMediaGroupUris = function resolveMediaGroupUris(master) {
  forEachMediaGroup(master, function (properties) {
    if (properties.uri) {
      properties.resolvedUri = resolveUrl(master.uri, properties.uri);
    }
  });
};

/**
 * Calculates the time to wait before refreshing a live playlist
 *
 * @param {Object} media
 *        The current media
 * @param {Boolean} update
 *        True if there were any updates from the last refresh, false otherwise
 * @return {Number}
 *         The time in ms to wait before refreshing the live playlist
 */
var refreshDelay = function refreshDelay(media, update) {
  var lastSegment = media.segments[media.segments.length - 1];
  var delay = void 0;

  if (update && lastSegment && lastSegment.duration) {
    delay = lastSegment.duration * 1000;
  } else {
    // if the playlist is unchanged since the last reload or last segment duration
    // cannot be determined, try again after half the target duration
    delay = (media.targetDuration || 10) * 500;
  }
  return delay;
};

/**
 * Load a playlist from a remote location
 *
 * @class PlaylistLoader
 * @extends Stream
 * @param {String} srcUrl the url to start with
 * @param {Boolean} withCredentials the withCredentials xhr option
 * @constructor
 */

var PlaylistLoader = function (_EventTarget) {
  inherits(PlaylistLoader, _EventTarget);

  function PlaylistLoader(srcUrl, hls) {
    var options = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : {};
    classCallCheck(this, PlaylistLoader);

    var _this = possibleConstructorReturn(this, (PlaylistLoader.__proto__ || Object.getPrototypeOf(PlaylistLoader)).call(this));

    var _options$withCredenti = options.withCredentials,
        withCredentials = _options$withCredenti === undefined ? false : _options$withCredenti,
        _options$handleManife = options.handleManifestRedirects,
        handleManifestRedirects = _options$handleManife === undefined ? false : _options$handleManife;


    _this.srcUrl = srcUrl;
    _this.hls_ = hls;
    _this.withCredentials = withCredentials;
    _this.handleManifestRedirects = handleManifestRedirects;

    var hlsOptions = hls.options_;

    _this.customTagParsers = hlsOptions && hlsOptions.customTagParsers || [];
    _this.customTagMappers = hlsOptions && hlsOptions.customTagMappers || [];

    if (!_this.srcUrl) {
      throw new Error('A non-empty playlist URL is required');
    }

    // initialize the loader state
    _this.state = 'HAVE_NOTHING';

    // live playlist staleness timeout
    _this.on('mediaupdatetimeout', function () {
      if (_this.state !== 'HAVE_METADATA') {
        // only refresh the media playlist if no other activity is going on
        return;
      }

      _this.state = 'HAVE_CURRENT_METADATA';

      _this.request = _this.hls_.xhr({
        uri: resolveUrl(_this.master.uri, _this.media().uri),
        withCredentials: _this.withCredentials
      }, function (error, req) {
        // disposed
        if (!_this.request) {
          return;
        }

        if (error) {
          return _this.playlistRequestError(_this.request, _this.media(), 'HAVE_METADATA');
        }

        _this.haveMetadata(_this.request, _this.media().uri, _this.media().id);
      });
    });
    return _this;
  }

  createClass(PlaylistLoader, [{
    key: 'playlistRequestError',
    value: function playlistRequestError(xhr, playlist, startingState) {
      var uri = playlist.uri,
          id = playlist.id;

      // any in-flight request is now finished

      this.request = null;

      if (startingState) {
        this.state = startingState;
      }

      this.error = {
        playlist: this.master.playlists[id],
        status: xhr.status,
        message: 'HLS playlist request error at URL: ' + uri + '.',
        responseText: xhr.responseText,
        code: xhr.status >= 500 ? 4 : 2
      };

      this.trigger('error');
    }

    // update the playlist loader's state in response to a new or
    // updated playlist.

  }, {
    key: 'haveMetadata',
    value: function haveMetadata(xhr, url, id) {
      var _this2 = this;

      // any in-flight request is now finished
      this.request = null;
      this.state = 'HAVE_METADATA';

      var parser = new Parser();

      // adding custom tag parsers
      this.customTagParsers.forEach(function (customParser) {
        return parser.addParser(customParser);
      });

      // adding custom tag mappers
      this.customTagMappers.forEach(function (mapper) {
        return parser.addTagMapper(mapper);
      });

      parser.push(xhr.responseText);
      parser.end();
      parser.manifest.uri = url;
      parser.manifest.id = id;
      // m3u8-parser does not attach an attributes property to media playlists so make
      // sure that the property is attached to avoid undefined reference errors
      parser.manifest.attributes = parser.manifest.attributes || {};

      // merge this playlist into the master
      var update = updateMaster(this.master, parser.manifest);

      this.targetDuration = parser.manifest.targetDuration;

      if (update) {
        this.master = update;
        this.media_ = this.master.playlists[id];
      } else {
        this.trigger('playlistunchanged');
      }

      // refresh live playlists after a target duration passes
      if (!this.media().endList) {
        window$1.clearTimeout(this.mediaUpdateTimeout);
        this.mediaUpdateTimeout = window$1.setTimeout(function () {
          _this2.trigger('mediaupdatetimeout');
        }, refreshDelay(this.media(), !!update));
      }

      this.trigger('loadedplaylist');
    }

    /**
     * Abort any outstanding work and clean up.
     */

  }, {
    key: 'dispose',
    value: function dispose() {
      this.trigger('dispose');
      this.stopRequest();
      window$1.clearTimeout(this.mediaUpdateTimeout);
      window$1.clearTimeout(this.finalRenditionTimeout);
      this.off();
    }
  }, {
    key: 'stopRequest',
    value: function stopRequest() {
      if (this.request) {
        var oldRequest = this.request;

        this.request = null;
        oldRequest.onreadystatechange = null;
        oldRequest.abort();
      }
    }

    /**
     * When called without any arguments, returns the currently
     * active media playlist. When called with a single argument,
     * triggers the playlist loader to asynchronously switch to the
     * specified media playlist. Calling this method while the
     * loader is in the HAVE_NOTHING causes an error to be emitted
     * but otherwise has no effect.
     *
     * @param {Object=} playlist the parsed media playlist
     * object to switch to
     * @param {Boolean=} is this the last available playlist
     *
     * @return {Playlist} the current loaded media
     */

  }, {
    key: 'media',
    value: function media(playlist, isFinalRendition) {
      var _this3 = this;

      // getter
      if (!playlist) {
        return this.media_;
      }

      // setter
      if (this.state === 'HAVE_NOTHING') {
        throw new Error('Cannot switch media playlist from ' + this.state);
      }

      // find the playlist object if the target playlist has been
      // specified by URI
      if (typeof playlist === 'string') {
        if (!this.master.playlists[playlist]) {
          throw new Error('Unknown playlist URI: ' + playlist);
        }
        playlist = this.master.playlists[playlist];
      }

      window$1.clearTimeout(this.finalRenditionTimeout);

      if (isFinalRendition) {
        var delay = playlist.targetDuration / 2 * 1000 || 5 * 1000;

        this.finalRenditionTimeout = window$1.setTimeout(this.media.bind(this, playlist, false), delay);
        return;
      }

      var startingState = this.state;
      var mediaChange = !this.media_ || playlist.id !== this.media_.id;

      // switch to fully loaded playlists immediately
      if (this.master.playlists[playlist.id].endList) {
        // abort outstanding playlist requests
        if (this.request) {
          this.request.onreadystatechange = null;
          this.request.abort();
          this.request = null;
        }
        this.state = 'HAVE_METADATA';
        this.media_ = playlist;

        // trigger media change if the active media has been updated
        if (mediaChange) {
          this.trigger('mediachanging');
          this.trigger('mediachange');
        }
        return;
      }

      // switching to the active playlist is a no-op
      if (!mediaChange) {
        return;
      }

      this.state = 'SWITCHING_MEDIA';

      // there is already an outstanding playlist request
      if (this.request) {
        if (playlist.resolvedUri === this.request.url) {
          // requesting to switch to the same playlist multiple times
          // has no effect after the first
          return;
        }
        this.request.onreadystatechange = null;
        this.request.abort();
        this.request = null;
      }

      // request the new playlist
      if (this.media_) {
        this.trigger('mediachanging');
      }

      this.request = this.hls_.xhr({
        uri: playlist.resolvedUri,
        withCredentials: this.withCredentials
      }, function (error, req) {
        // disposed
        if (!_this3.request) {
          return;
        }

        playlist.resolvedUri = resolveManifestRedirect(_this3.handleManifestRedirects, playlist.resolvedUri, req);

        if (error) {
          return _this3.playlistRequestError(_this3.request, playlist, startingState);
        }

        _this3.haveMetadata(req, playlist.uri, playlist.id);

        // fire loadedmetadata the first time a media playlist is loaded
        if (startingState === 'HAVE_MASTER') {
          _this3.trigger('loadedmetadata');
        } else {
          _this3.trigger('mediachange');
        }
      });
    }

    /**
     * pause loading of the playlist
     */

  }, {
    key: 'pause',
    value: function pause() {
      this.stopRequest();
      window$1.clearTimeout(this.mediaUpdateTimeout);
      if (this.state === 'HAVE_NOTHING') {
        // If we pause the loader before any data has been retrieved, its as if we never
        // started, so reset to an unstarted state.
        this.started = false;
      }
      // Need to restore state now that no activity is happening
      if (this.state === 'SWITCHING_MEDIA') {
        // if the loader was in the process of switching media, it should either return to
        // HAVE_MASTER or HAVE_METADATA depending on if the loader has loaded a media
        // playlist yet. This is determined by the existence of loader.media_
        if (this.media_) {
          this.state = 'HAVE_METADATA';
        } else {
          this.state = 'HAVE_MASTER';
        }
      } else if (this.state === 'HAVE_CURRENT_METADATA') {
        this.state = 'HAVE_METADATA';
      }
    }

    /**
     * start loading of the playlist
     */

  }, {
    key: 'load',
    value: function load(isFinalRendition) {
      var _this4 = this;

      window$1.clearTimeout(this.mediaUpdateTimeout);

      var media = this.media();

      if (isFinalRendition) {
        var delay = media ? media.targetDuration / 2 * 1000 : 5 * 1000;

        this.mediaUpdateTimeout = window$1.setTimeout(function () {
          return _this4.load();
        }, delay);
        return;
      }

      if (!this.started) {
        this.start();
        return;
      }

      if (media && !media.endList) {
        this.trigger('mediaupdatetimeout');
      } else {
        this.trigger('loadedplaylist');
      }
    }

    /**
     * start loading of the playlist
     */

  }, {
    key: 'start',
    value: function start() {
      var _this5 = this;

      this.started = true;

      // request the specified URL
      this.request = this.hls_.xhr({
        uri: this.srcUrl,
        withCredentials: this.withCredentials
      }, function (error, req) {
        // disposed
        if (!_this5.request) {
          return;
        }

        // clear the loader's request reference
        _this5.request = null;

        if (error) {
          _this5.error = {
            status: req.status,
            message: 'HLS playlist request error at URL: ' + _this5.srcUrl + '.',
            responseText: req.responseText,
            // MEDIA_ERR_NETWORK
            code: 2
          };
          if (_this5.state === 'HAVE_NOTHING') {
            _this5.started = false;
          }
          return _this5.trigger('error');
        }

        var parser = new Parser();

        // adding custom tag parsers
        _this5.customTagParsers.forEach(function (customParser) {
          return parser.addParser(customParser);
        });

        // adding custom tag mappers
        _this5.customTagMappers.forEach(function (mapper) {
          return parser.addTagMapper(mapper);
        });

        parser.push(req.responseText);
        parser.end();

        _this5.state = 'HAVE_MASTER';

        _this5.srcUrl = resolveManifestRedirect(_this5.handleManifestRedirects, _this5.srcUrl, req);

        parser.manifest.uri = _this5.srcUrl;

        // loaded a master playlist
        if (parser.manifest.playlists) {
          _this5.master = parser.manifest;

          setupMediaPlaylists(_this5.master);
          resolveMediaGroupUris(_this5.master);

          _this5.trigger('loadedplaylist');
          if (!_this5.request) {
            // no media playlist was specifically selected so start
            // from the first listed one
            _this5.media(parser.manifest.playlists[0]);
          }
          return;
        }

        var id = createPlaylistID(0, _this5.srcUrl);

        // loaded a media playlist
        // infer a master playlist if none was previously requested
        _this5.master = {
          mediaGroups: {
            'AUDIO': {},
            'VIDEO': {},
            'CLOSED-CAPTIONS': {},
            'SUBTITLES': {}
          },
          uri: window$1.location.href,
          playlists: [{
            uri: _this5.srcUrl,
            id: id,
            resolvedUri: _this5.srcUrl,
            // m3u8-parser does not attach an attributes property to media playlists so make
            // sure that the property is attached to avoid undefined reference errors
            attributes: {}
          }]
        };
        _this5.master.playlists[id] = _this5.master.playlists[0];
        // URI reference added for backwards compatibility
        _this5.master.playlists[_this5.srcUrl] = _this5.master.playlists[0];

        _this5.haveMetadata(req, _this5.srcUrl, id);
        return _this5.trigger('loadedmetadata');
      });
    }
  }]);
  return PlaylistLoader;
}(EventTarget);

/**
 * @file playlist.js
 *
 * Playlist related utilities.
 */

var createTimeRange = videojs.createTimeRange;

/**
 * walk backward until we find a duration we can use
 * or return a failure
 *
 * @param {Playlist} playlist the playlist to walk through
 * @param {Number} endSequence the mediaSequence to stop walking on
 */

var backwardDuration = function backwardDuration(playlist, endSequence) {
  var result = 0;
  var i = endSequence - playlist.mediaSequence;
  // if a start time is available for segment immediately following
  // the interval, use it
  var segment = playlist.segments[i];

  // Walk backward until we find the latest segment with timeline
  // information that is earlier than endSequence
  if (segment) {
    if (typeof segment.start !== 'undefined') {
      return { result: segment.start, precise: true };
    }
    if (typeof segment.end !== 'undefined') {
      return {
        result: segment.end - segment.duration,
        precise: true
      };
    }
  }
  while (i--) {
    segment = playlist.segments[i];
    if (typeof segment.end !== 'undefined') {
      return { result: result + segment.end, precise: true };
    }

    result += segment.duration;

    if (typeof segment.start !== 'undefined') {
      return { result: result + segment.start, precise: true };
    }
  }
  return { result: result, precise: false };
};

/**
 * walk forward until we find a duration we can use
 * or return a failure
 *
 * @param {Playlist} playlist the playlist to walk through
 * @param {Number} endSequence the mediaSequence to stop walking on
 */
var forwardDuration = function forwardDuration(playlist, endSequence) {
  var result = 0;
  var segment = void 0;
  var i = endSequence - playlist.mediaSequence;
  // Walk forward until we find the earliest segment with timeline
  // information

  for (; i < playlist.segments.length; i++) {
    segment = playlist.segments[i];
    if (typeof segment.start !== 'undefined') {
      return {
        result: segment.start - result,
        precise: true
      };
    }

    result += segment.duration;

    if (typeof segment.end !== 'undefined') {
      return {
        result: segment.end - result,
        precise: true
      };
    }
  }
  // indicate we didn't find a useful duration estimate
  return { result: -1, precise: false };
};

/**
  * Calculate the media duration from the segments associated with a
  * playlist. The duration of a subinterval of the available segments
  * may be calculated by specifying an end index.
  *
  * @param {Object} playlist a media playlist object
  * @param {Number=} endSequence an exclusive upper boundary
  * for the playlist.  Defaults to playlist length.
  * @param {Number} expired the amount of time that has dropped
  * off the front of the playlist in a live scenario
  * @return {Number} the duration between the first available segment
  * and end index.
  */
var intervalDuration = function intervalDuration(playlist, endSequence, expired) {
  var backward = void 0;
  var forward = void 0;

  if (typeof endSequence === 'undefined') {
    endSequence = playlist.mediaSequence + playlist.segments.length;
  }

  if (endSequence < playlist.mediaSequence) {
    return 0;
  }

  // do a backward walk to estimate the duration
  backward = backwardDuration(playlist, endSequence);
  if (backward.precise) {
    // if we were able to base our duration estimate on timing
    // information provided directly from the Media Source, return
    // it
    return backward.result;
  }

  // walk forward to see if a precise duration estimate can be made
  // that way
  forward = forwardDuration(playlist, endSequence);
  if (forward.precise) {
    // we found a segment that has been buffered and so it's
    // position is known precisely
    return forward.result;
  }

  // return the less-precise, playlist-based duration estimate
  return backward.result + expired;
};

/**
  * Calculates the duration of a playlist. If a start and end index
  * are specified, the duration will be for the subset of the media
  * timeline between those two indices. The total duration for live
  * playlists is always Infinity.
  *
  * @param {Object} playlist a media playlist object
  * @param {Number=} endSequence an exclusive upper
  * boundary for the playlist. Defaults to the playlist media
  * sequence number plus its length.
  * @param {Number=} expired the amount of time that has
  * dropped off the front of the playlist in a live scenario
  * @return {Number} the duration between the start index and end
  * index.
  */
var duration = function duration(playlist, endSequence, expired) {
  if (!playlist) {
    return 0;
  }

  if (typeof expired !== 'number') {
    expired = 0;
  }

  // if a slice of the total duration is not requested, use
  // playlist-level duration indicators when they're present
  if (typeof endSequence === 'undefined') {
    // if present, use the duration specified in the playlist
    if (playlist.totalDuration) {
      return playlist.totalDuration;
    }

    // duration should be Infinity for live playlists
    if (!playlist.endList) {
      return window$1.Infinity;
    }
  }

  // calculate the total duration based on the segment durations
  return intervalDuration(playlist, endSequence, expired);
};

/**
  * Calculate the time between two indexes in the current playlist
  * neight the start- nor the end-index need to be within the current
  * playlist in which case, the targetDuration of the playlist is used
  * to approximate the durations of the segments
  *
  * @param {Object} playlist a media playlist object
  * @param {Number} startIndex
  * @param {Number} endIndex
  * @return {Number} the number of seconds between startIndex and endIndex
  */
var sumDurations = function sumDurations(playlist, startIndex, endIndex) {
  var durations = 0;

  if (startIndex > endIndex) {
    var _ref = [endIndex, startIndex];
    startIndex = _ref[0];
    endIndex = _ref[1];
  }

  if (startIndex < 0) {
    for (var i = startIndex; i < Math.min(0, endIndex); i++) {
      durations += playlist.targetDuration;
    }
    startIndex = 0;
  }

  for (var _i = startIndex; _i < endIndex; _i++) {
    durations += playlist.segments[_i].duration;
  }

  return durations;
};

/**
 * Determines the media index of the segment corresponding to the safe edge of the live
 * window which is the duration of the last segment plus 2 target durations from the end
 * of the playlist.
 *
 * A liveEdgePadding can be provided which will be used instead of calculating the safe live edge.
 * This corresponds to suggestedPresentationDelay in DASH manifests.
 *
 * @param {Object} playlist
 *        a media playlist object
 * @param {Number} [liveEdgePadding]
 *        A number in seconds indicating how far from the end we want to be.
 *        If provided, this value is used instead of calculating the safe live index from the target durations.
 *        Corresponds to suggestedPresentationDelay in DASH manifests.
 * @return {Number}
 *         The media index of the segment at the safe live point. 0 if there is no "safe"
 *         point.
 * @function safeLiveIndex
 */
var safeLiveIndex = function safeLiveIndex(playlist, liveEdgePadding) {
  if (!playlist.segments.length) {
    return 0;
  }

  var i = playlist.segments.length;
  var lastSegmentDuration = playlist.segments[i - 1].duration || playlist.targetDuration;
  var safeDistance = typeof liveEdgePadding === 'number' ? liveEdgePadding : lastSegmentDuration + playlist.targetDuration * 2;

  if (safeDistance === 0) {
    return i;
  }

  var distanceFromEnd = 0;

  while (i--) {
    distanceFromEnd += playlist.segments[i].duration;

    if (distanceFromEnd >= safeDistance) {
      break;
    }
  }

  return Math.max(0, i);
};

/**
 * Calculates the playlist end time
 *
 * @param {Object} playlist a media playlist object
 * @param {Number=} expired the amount of time that has
 *                  dropped off the front of the playlist in a live scenario
 * @param {Boolean|false} useSafeLiveEnd a boolean value indicating whether or not the
 *                        playlist end calculation should consider the safe live end
 *                        (truncate the playlist end by three segments). This is normally
 *                        used for calculating the end of the playlist's seekable range.
 *                        This takes into account the value of liveEdgePadding.
 *                        Setting liveEdgePadding to 0 is equivalent to setting this to false.
 * @param {Number} liveEdgePadding a number indicating how far from the end of the playlist we should be in seconds.
 *                 If this is provided, it is used in the safe live end calculation.
 *                 Setting useSafeLiveEnd=false or liveEdgePadding=0 are equivalent.
 *                 Corresponds to suggestedPresentationDelay in DASH manifests.
 * @returns {Number} the end time of playlist
 * @function playlistEnd
 */
var playlistEnd = function playlistEnd(playlist, expired, useSafeLiveEnd, liveEdgePadding) {
  if (!playlist || !playlist.segments) {
    return null;
  }
  if (playlist.endList) {
    return duration(playlist);
  }

  if (expired === null) {
    return null;
  }

  expired = expired || 0;

  var endSequence = useSafeLiveEnd ? safeLiveIndex(playlist, liveEdgePadding) : playlist.segments.length;

  return intervalDuration(playlist, playlist.mediaSequence + endSequence, expired);
};

/**
  * Calculates the interval of time that is currently seekable in a
  * playlist. The returned time ranges are relative to the earliest
  * moment in the specified playlist that is still available. A full
  * seekable implementation for live streams would need to offset
  * these values by the duration of content that has expired from the
  * stream.
  *
  * @param {Object} playlist a media playlist object
  * dropped off the front of the playlist in a live scenario
  * @param {Number=} expired the amount of time that has
  * dropped off the front of the playlist in a live scenario
  * @param {Number} liveEdgePadding how far from the end of the playlist we should be in seconds.
  *        Corresponds to suggestedPresentationDelay in DASH manifests.
  * @return {TimeRanges} the periods of time that are valid targets
  * for seeking
  */
var seekable = function seekable(playlist, expired, liveEdgePadding) {
  var useSafeLiveEnd = true;
  var seekableStart = expired || 0;
  var seekableEnd = playlistEnd(playlist, expired, useSafeLiveEnd, liveEdgePadding);

  if (seekableEnd === null) {
    return createTimeRange();
  }
  return createTimeRange(seekableStart, seekableEnd);
};

var isWholeNumber = function isWholeNumber(num) {
  return num - Math.floor(num) === 0;
};

var roundSignificantDigit = function roundSignificantDigit(increment, num) {
  // If we have a whole number, just add 1 to it
  if (isWholeNumber(num)) {
    return num + increment * 0.1;
  }

  var numDecimalDigits = num.toString().split('.')[1].length;

  for (var i = 1; i <= numDecimalDigits; i++) {
    var scale = Math.pow(10, i);
    var temp = num * scale;

    if (isWholeNumber(temp) || i === numDecimalDigits) {
      return (temp + increment) / scale;
    }
  }
};

var ceilLeastSignificantDigit = roundSignificantDigit.bind(null, 1);
var floorLeastSignificantDigit = roundSignificantDigit.bind(null, -1);

/**
 * Determine the index and estimated starting time of the segment that
 * contains a specified playback position in a media playlist.
 *
 * @param {Object} playlist the media playlist to query
 * @param {Number} currentTime The number of seconds since the earliest
 * possible position to determine the containing segment for
 * @param {Number} startIndex
 * @param {Number} startTime
 * @return {Object}
 */
var getMediaInfoForTime = function getMediaInfoForTime(playlist, currentTime, startIndex, startTime) {
  var i = void 0;
  var segment = void 0;
  var numSegments = playlist.segments.length;

  var time = currentTime - startTime;

  if (time < 0) {
    // Walk backward from startIndex in the playlist, adding durations
    // until we find a segment that contains `time` and return it
    if (startIndex > 0) {
      for (i = startIndex - 1; i >= 0; i--) {
        segment = playlist.segments[i];
        time += floorLeastSignificantDigit(segment.duration);
        if (time > 0) {
          return {
            mediaIndex: i,
            startTime: startTime - sumDurations(playlist, startIndex, i)
          };
        }
      }
    }
    // We were unable to find a good segment within the playlist
    // so select the first segment
    return {
      mediaIndex: 0,
      startTime: currentTime
    };
  }

  // When startIndex is negative, we first walk forward to first segment
  // adding target durations. If we "run out of time" before getting to
  // the first segment, return the first segment
  if (startIndex < 0) {
    for (i = startIndex; i < 0; i++) {
      time -= playlist.targetDuration;
      if (time < 0) {
        return {
          mediaIndex: 0,
          startTime: currentTime
        };
      }
    }
    startIndex = 0;
  }

  // Walk forward from startIndex in the playlist, subtracting durations
  // until we find a segment that contains `time` and return it
  for (i = startIndex; i < numSegments; i++) {
    segment = playlist.segments[i];
    time -= ceilLeastSignificantDigit(segment.duration);
    if (time < 0) {
      return {
        mediaIndex: i,
        startTime: startTime + sumDurations(playlist, startIndex, i)
      };
    }
  }

  // We are out of possible candidates so load the last one...
  return {
    mediaIndex: numSegments - 1,
    startTime: currentTime
  };
};

/**
 * Check whether the playlist is blacklisted or not.
 *
 * @param {Object} playlist the media playlist object
 * @return {boolean} whether the playlist is blacklisted or not
 * @function isBlacklisted
 */
var isBlacklisted = function isBlacklisted(playlist) {
  return playlist.excludeUntil && playlist.excludeUntil > Date.now();
};

/**
 * Check whether the playlist is compatible with current playback configuration or has
 * been blacklisted permanently for being incompatible.
 *
 * @param {Object} playlist the media playlist object
 * @return {boolean} whether the playlist is incompatible or not
 * @function isIncompatible
 */
var isIncompatible = function isIncompatible(playlist) {
  return playlist.excludeUntil && playlist.excludeUntil === Infinity;
};

/**
 * Check whether the playlist is enabled or not.
 *
 * @param {Object} playlist the media playlist object
 * @return {boolean} whether the playlist is enabled or not
 * @function isEnabled
 */
var isEnabled = function isEnabled(playlist) {
  var blacklisted = isBlacklisted(playlist);

  return !playlist.disabled && !blacklisted;
};

/**
 * Check whether the playlist has been manually disabled through the representations api.
 *
 * @param {Object} playlist the media playlist object
 * @return {boolean} whether the playlist is disabled manually or not
 * @function isDisabled
 */
var isDisabled = function isDisabled(playlist) {
  return playlist.disabled;
};

/**
 * Returns whether the current playlist is an AES encrypted HLS stream
 *
 * @return {Boolean} true if it's an AES encrypted HLS stream
 */
var isAes = function isAes(media) {
  for (var i = 0; i < media.segments.length; i++) {
    if (media.segments[i].key) {
      return true;
    }
  }
  return false;
};

/**
 * Returns whether the current playlist contains fMP4
 *
 * @return {Boolean} true if the playlist contains fMP4
 */
var isFmp4 = function isFmp4(media) {
  for (var i = 0; i < media.segments.length; i++) {
    if (media.segments[i].map) {
      return true;
    }
  }
  return false;
};

/**
 * Checks if the playlist has a value for the specified attribute
 *
 * @param {String} attr
 *        Attribute to check for
 * @param {Object} playlist
 *        The media playlist object
 * @return {Boolean}
 *         Whether the playlist contains a value for the attribute or not
 * @function hasAttribute
 */
var hasAttribute = function hasAttribute(attr, playlist) {
  return playlist.attributes && playlist.attributes[attr];
};

/**
 * Estimates the time required to complete a segment download from the specified playlist
 *
 * @param {Number} segmentDuration
 *        Duration of requested segment
 * @param {Number} bandwidth
 *        Current measured bandwidth of the player
 * @param {Object} playlist
 *        The media playlist object
 * @param {Number=} bytesReceived
 *        Number of bytes already received for the request. Defaults to 0
 * @return {Number|NaN}
 *         The estimated time to request the segment. NaN if bandwidth information for
 *         the given playlist is unavailable
 * @function estimateSegmentRequestTime
 */
var estimateSegmentRequestTime = function estimateSegmentRequestTime(segmentDuration, bandwidth, playlist) {
  var bytesReceived = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : 0;

  if (!hasAttribute('BANDWIDTH', playlist)) {
    return NaN;
  }

  var size = segmentDuration * playlist.attributes.BANDWIDTH;

  return (size - bytesReceived * 8) / bandwidth;
};

/*
 * Returns whether the current playlist is the lowest rendition
 *
 * @return {Boolean} true if on lowest rendition
 */
var isLowestEnabledRendition = function isLowestEnabledRendition(master, media) {
  if (master.playlists.length === 1) {
    return true;
  }

  var currentBandwidth = media.attributes.BANDWIDTH || Number.MAX_VALUE;

  return master.playlists.filter(function (playlist) {
    if (!isEnabled(playlist)) {
      return false;
    }

    return (playlist.attributes.BANDWIDTH || 0) < currentBandwidth;
  }).length === 0;
};

// exports
var Playlist = {
  duration: duration,
  seekable: seekable,
  safeLiveIndex: safeLiveIndex,
  getMediaInfoForTime: getMediaInfoForTime,
  isEnabled: isEnabled,
  isDisabled: isDisabled,
  isBlacklisted: isBlacklisted,
  isIncompatible: isIncompatible,
  playlistEnd: playlistEnd,
  isAes: isAes,
  isFmp4: isFmp4,
  hasAttribute: hasAttribute,
  estimateSegmentRequestTime: estimateSegmentRequestTime,
  isLowestEnabledRendition: isLowestEnabledRendition
};

/**
 * @file xhr.js
 */

var videojsXHR = videojs.xhr,
    mergeOptions$1 = videojs.mergeOptions;


var xhrFactory = function xhrFactory() {
  var xhr = function XhrFunction(options, callback) {
    // Add a default timeout for all hls requests
    options = mergeOptions$1({
      timeout: 45e3
    }, options);

    // Allow an optional user-specified function to modify the option
    // object before we construct the xhr request
    var beforeRequest = XhrFunction.beforeRequest || videojs.Hls.xhr.beforeRequest;

    if (beforeRequest && typeof beforeRequest === 'function') {
      var newOptions = beforeRequest(options);

      if (newOptions) {
        options = newOptions;
      }
    }

    var request = videojsXHR(options, function (error, response) {
      var reqResponse = request.response;

      if (!error && reqResponse) {
        request.responseTime = Date.now();
        request.roundTripTime = request.responseTime - request.requestTime;
        request.bytesReceived = reqResponse.byteLength || reqResponse.length;
        if (!request.bandwidth) {
          request.bandwidth = Math.floor(request.bytesReceived / request.roundTripTime * 8 * 1000);
        }
      }

      if (response.headers) {
        request.responseHeaders = response.headers;
      }

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

      // 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 && !request.aborted && response.statusCode !== 200 && response.statusCode !== 206 && response.statusCode !== 0) {
        error = new Error('XHR Failed with a response of: ' + (request && (reqResponse || request.responseText)));
      }

      callback(error, request);
    });
    var originalAbort = request.abort;

    request.abort = function () {
      request.aborted = true;
      return originalAbort.apply(request, arguments);
    };
    request.uri = options.uri;
    request.requestTime = Date.now();
    return request;
  };

  return xhr;
};

/**
 * Turns segment byterange into a string suitable for use in
 * HTTP Range requests
 *
 * @param {Object} byterange - an object with two values defining the start and end
 *                             of a byte-range
 */
var byterangeStr = function byterangeStr(byterange) {
  var byterangeStart = void 0;
  var byterangeEnd = void 0;

  // `byterangeEnd` is one less than `offset + length` because the HTTP range
  // header uses inclusive ranges
  byterangeEnd = byterange.offset + byterange.length - 1;
  byterangeStart = byterange.offset;
  return 'bytes=' + byterangeStart + '-' + byterangeEnd;
};

/**
 * Defines headers for use in the xhr request for a particular segment.
 *
 * @param {Object} segment - a simplified copy of the segmentInfo object
 *                           from SegmentLoader
 */
var segmentXhrHeaders = function segmentXhrHeaders(segment) {
  var headers = {};

  if (segment.byterange) {
    headers.Range = byterangeStr(segment.byterange);
  }
  return headers;
};

/**
 * @file bin-utils.js
 */

/**
 * convert a TimeRange to text
 *
 * @param {TimeRange} range the timerange to use for conversion
 * @param {Number} i the iterator on the range to convert
 */
var textRange = function textRange(range, i) {
  return range.start(i) + '-' + range.end(i);
};

/**
 * format a number as hex string
 *
 * @param {Number} e The number
 * @param {Number} i the iterator
 */
var formatHexString = function formatHexString(e, i) {
  var value = e.toString(16);

  return '00'.substring(0, 2 - value.length) + value + (i % 2 ? ' ' : '');
};
var formatAsciiString = function formatAsciiString(e) {
  if (e >= 0x20 && e < 0x7e) {
    return String.fromCharCode(e);
  }
  return '.';
};

/**
 * Creates an object for sending to a web worker modifying properties that are TypedArrays
 * into a new object with seperated properties for the buffer, byteOffset, and byteLength.
 *
 * @param {Object} message
 *        Object of properties and values to send to the web worker
 * @return {Object}
 *         Modified message with TypedArray values expanded
 * @function createTransferableMessage
 */
var createTransferableMessage = function createTransferableMessage(message) {
  var transferable = {};

  Object.keys(message).forEach(function (key) {
    var value = message[key];

    if (ArrayBuffer.isView(value)) {
      transferable[key] = {
        bytes: value.buffer,
        byteOffset: value.byteOffset,
        byteLength: value.byteLength
      };
    } else {
      transferable[key] = value;
    }
  });

  return transferable;
};

/**
 * Returns a unique string identifier for a media initialization
 * segment.
 */
var initSegmentId = function initSegmentId(initSegment) {
  var byterange = initSegment.byterange || {
    length: Infinity,
    offset: 0
  };

  return [byterange.length, byterange.offset, initSegment.resolvedUri].join(',');
};

/**
 * Returns a unique string identifier for a media segment key.
 */
var segmentKeyId = function segmentKeyId(key) {
  return key.resolvedUri;
};

/**
 * utils to help dump binary data to the console
 */
var hexDump = function hexDump(data) {
  var bytes = Array.prototype.slice.call(data);
  var step = 16;
  var result = '';
  var hex = void 0;
  var ascii = void 0;

  for (var j = 0; j < bytes.length / step; j++) {
    hex = bytes.slice(j * step, j * step + step).map(formatHexString).join('');
    ascii = bytes.slice(j * step, j * step + step).map(formatAsciiString).join('');
    result += hex + ' ' + ascii + '\n';
  }

  return result;
};

var tagDump = function tagDump(_ref) {
  var bytes = _ref.bytes;
  return hexDump(bytes);
};

var textRanges = function textRanges(ranges) {
  var result = '';
  var i = void 0;

  for (i = 0; i < ranges.length; i++) {
    result += textRange(ranges, i) + ' ';
  }
  return result;
};

var utils = /*#__PURE__*/Object.freeze({
  createTransferableMessage: createTransferableMessage,
  initSegmentId: initSegmentId,
  segmentKeyId: segmentKeyId,
  hexDump: hexDump,
  tagDump: tagDump,
  textRanges: textRanges
});

// TODO handle fmp4 case where the timing info is accurate and doesn't involve transmux

// Add 25% to the segment duration to account for small discrepencies in segment timing.
// 25% was arbitrarily chosen, and may need to be refined over time.
var SEGMENT_END_FUDGE_PERCENT = 0.25;

/**
 * Co