Source: lib/hls/hls_parser.js

  1. /*! @license
  2.  * Shaka Player
  3.  * Copyright 2016 Google LLC
  4.  * SPDX-License-Identifier: Apache-2.0
  5.  */
  8. goog.provide('shaka.hls.HlsParser');
  10. goog.require('goog.Uri');
  11. goog.require('goog.asserts');
  12. goog.require('shaka.abr.Ewma');
  13. goog.require('shaka.hls.ManifestTextParser');
  14. goog.require('shaka.hls.Playlist');
  15. goog.require('shaka.hls.PlaylistType');
  16. goog.require('shaka.hls.Tag');
  17. goog.require('shaka.hls.Utils');
  18. goog.require('shaka.log');
  19. goog.require('shaka.media.InitSegmentReference');
  20. goog.require('shaka.media.ManifestParser');
  21. goog.require('shaka.media.PresentationTimeline');
  22. goog.require('shaka.media.QualityObserver');
  23. goog.require('shaka.media.SegmentIndex');
  24. goog.require('shaka.media.SegmentReference');
  25. goog.require('shaka.net.DataUriPlugin');
  26. goog.require('shaka.net.NetworkingEngine');
  27. goog.require('shaka.util.ArrayUtils');
  28. goog.require('shaka.util.BufferUtils');
  29. goog.require('shaka.util.DrmUtils');
  30. goog.require('shaka.util.ContentSteeringManager');
  31. goog.require('shaka.util.Error');
  32. goog.require('shaka.util.EventManager');
  33. goog.require('shaka.util.FakeEvent');
  34. goog.require('shaka.util.LanguageUtils');
  35. goog.require('shaka.util.ManifestParserUtils');
  36. goog.require('shaka.util.MimeUtils');
  37. goog.require('shaka.util.Networking');
  38. goog.require('shaka.util.OperationManager');
  39. goog.require('shaka.util.Pssh');
  40. goog.require('shaka.media.SegmentUtils');
  41. goog.require('shaka.util.Timer');
  42. goog.require('shaka.util.TsParser');
  43. goog.require('shaka.util.TXml');
  44. goog.require('shaka.util.Platform');
  45. goog.require('shaka.util.Uint8ArrayUtils');
  46. goog.requireType('shaka.hls.Segment');
  49. /**
  50.  * HLS parser.
  51.  *
  52.  * @implements {shaka.extern.ManifestParser}
  53.  * @export
  54.  */
  55. shaka.hls.HlsParser = class {
  56.   /**
  57.    * Creates an Hls Parser object.
  58.    */
  59.   constructor() {
  60.     /** @private {?shaka.extern.ManifestParser.PlayerInterface} */
  61.     this.playerInterface_ = null;
  63.     /** @private {?shaka.extern.ManifestConfiguration} */
  64.     this.config_ = null;
  66.     /** @private {number} */
  67.     this.globalId_ = 1;
  69.     /** @private {!Map.<string, string>} */
  70.     this.globalVariables_ = new Map();
  72.     /**
  73.      * A map from group id to stream infos created from the media tags.
  74.      * @private {!Map.<string, !Array.<?shaka.hls.HlsParser.StreamInfo>>}
  75.      */
  76.     this.groupIdToStreamInfosMap_ = new Map();
  78.     /**
  79.      * For media playlist lazy-loading to work in livestreams, we have to assume
  80.      * that each stream of a type (video, audio, etc) has the same mappings of
  81.      * sequence number to start time.
  82.      * This map stores those relationships.
  83.      * Only used during livestreams; we do not assume that VOD content is
  84.      * aligned in that way.
  85.      * @private {!Map.<string, !Map.<number, number>>}
  86.      */
  87.     this.mediaSequenceToStartTimeByType_ = new Map();
  89.     // Set initial maps.
  90.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  91.     this.mediaSequenceToStartTimeByType_.set(ContentType.VIDEO, new Map());
  92.     this.mediaSequenceToStartTimeByType_.set(ContentType.AUDIO, new Map());
  93.     this.mediaSequenceToStartTimeByType_.set(ContentType.TEXT, new Map());
  94.     this.mediaSequenceToStartTimeByType_.set(ContentType.IMAGE, new Map());
  96.     /**
  97.      * The values are strings of the form "<VIDEO URI> - <AUDIO URI>",
  98.      * where the URIs are the verbatim media playlist URIs as they appeared in
  99.      * the master playlist.
  100.      *
  101.      * Used to avoid duplicates that vary only in their text stream.
  102.      *
  103.      * @private {!Set.<string>}
  104.      */
  105.     this.variantUriSet_ = new Set();
  107.     /**
  108.      * A map from (verbatim) media playlist URI to stream infos representing the
  109.      * playlists.
  110.      *
  111.      * On update, used to iterate through and update from media playlists.
  112.      *
  113.      * On initial parse, used to iterate through and determine minimum
  114.      * timestamps, offsets, and to handle TS rollover.
  115.      *
  116.      * During parsing, used to avoid duplicates in the async methods
  117.      * createStreamInfoFromMediaTags_, createStreamInfoFromImageTag_ and
  118.      * createStreamInfoFromVariantTags_.
  119.      *
  120.      * @private {!Map.<string, shaka.hls.HlsParser.StreamInfo>}
  121.      */
  122.     this.uriToStreamInfosMap_ = new Map();
  124.     /** @private {?shaka.media.PresentationTimeline} */
  125.     this.presentationTimeline_ = null;
  127.     /**
  128.      * The master playlist URI, after redirects.
  129.      *
  130.      * @private {string}
  131.      */
  132.     this.masterPlaylistUri_ = '';
  134.     /** @private {shaka.hls.ManifestTextParser} */
  135.     this.manifestTextParser_ = new shaka.hls.ManifestTextParser();
  137.     /**
  138.      * The minimum sequence number for generated segments, when ignoring
  139.      * EXT-X-PROGRAM-DATE-TIME.
  140.      *
  141.      * @private {number}
  142.      */
  143.     this.minSequenceNumber_ = -1;
  145.     /**
  146.      * The lowest time value for any of the streams, as defined by the
  147.      * EXT-X-PROGRAM-DATE-TIME value. Measured in seconds since January 1, 1970.
  148.      *
  149.      * @private {number}
  150.      */
  151.     this.lowestSyncTime_ = Infinity;
  153.     /**
  154.      * Whether the streams have previously been "finalized"; that is to say,
  155.      * whether we have loaded enough streams to know information about the asset
  156.      * such as timing information, live status, etc.
  157.      *
  158.      * @private {boolean}
  159.      */
  160.     this.streamsFinalized_ = false;
  162.     /**
  163.      * Whether the manifest informs about the codec to use.
  164.      *
  165.      * @private
  166.      */
  167.     this.codecInfoInManifest_ = false;
  169.     /**
  170.      * This timer is used to trigger the start of a manifest update. A manifest
  171.      * update is async. Once the update is finished, the timer will be restarted
  172.      * to trigger the next update. The timer will only be started if the content
  173.      * is live content.
  174.      *
  175.      * @private {shaka.util.Timer}
  176.      */
  177.     this.updatePlaylistTimer_ = new shaka.util.Timer(() => {
  178.       if (this.mediaElement_ && !this.config_.continueLoadingWhenPaused) {
  179.         this.eventManager_.unlisten(this.mediaElement_, 'timeupdate');
  180.         if (this.mediaElement_.paused) {
  181.           this.eventManager_.listenOnce(
  182.               this.mediaElement_, 'timeupdate', () => this.onUpdate_());
  183.           return;
  184.         }
  185.       }
  186.       this.onUpdate_();
  187.     });
  189.     /** @private {shaka.hls.HlsParser.PresentationType_} */
  190.     this.presentationType_ = shaka.hls.HlsParser.PresentationType_.VOD;
  192.     /** @private {?shaka.extern.Manifest} */
  193.     this.manifest_ = null;
  195.     /** @private {number} */
  196.     this.maxTargetDuration_ = 0;
  198.     /** @private {number} */
  199.     this.lastTargetDuration_ = Infinity;
  201.     /** Partial segments target duration.
  202.      * @private {number}
  203.      */
  204.     this.partialTargetDuration_ = 0;
  206.     /** @private {number} */
  207.     this.presentationDelay_ = 0;
  209.     /** @private {number} */
  210.     this.lowLatencyPresentationDelay_ = 0;
  212.     /** @private {shaka.util.OperationManager} */
  213.     this.operationManager_ = new shaka.util.OperationManager();
  215.     /** A map from closed captions' group id, to a map of closed captions info.
  216.      * {group id -> {closed captions channel id -> language}}
  217.      * @private {Map.<string, Map.<string, string>>}
  218.      */
  219.     this.groupIdToClosedCaptionsMap_ = new Map();
  221.     /** @private {Map.<string, string>} */
  222.     this.groupIdToCodecsMap_ = new Map();
  224.     /** A cache mapping EXT-X-MAP tag info to the InitSegmentReference created
  225.      * from the tag.
  226.      * The key is a string combining the EXT-X-MAP tag's absolute uri, and
  227.      * its BYTERANGE if available.
  228.      * {!Map.<string, !shaka.media.InitSegmentReference>} */
  229.     this.mapTagToInitSegmentRefMap_ = new Map();
  231.     /** @private {Map.<string, !shaka.extern.aesKey>} */
  232.     this.aesKeyInfoMap_ = new Map();
  234.     /** @private {Map.<string, !Promise.<shaka.extern.Response>>} */
  235.     this.aesKeyMap_ = new Map();
  237.     /** @private {Map.<string, !Promise.<shaka.extern.Response>>} */
  238.     this.identityKeyMap_ = new Map();
  240.     /** @private {Map.<!shaka.media.InitSegmentReference, ?string>} */
  241.     this.identityKidMap_ = new Map();
  243.     /** @private {boolean} */
  244.     this.lowLatencyMode_ = false;
  246.     /** @private {boolean} */
  247.     this.lowLatencyByterangeOptimization_ = false;
  249.     /**
  250.      * An ewma that tracks how long updates take.
  251.      * This is to mitigate issues caused by slow parsing on embedded devices.
  252.      * @private {!shaka.abr.Ewma}
  253.      */
  254.     this.averageUpdateDuration_ = new shaka.abr.Ewma(5);
  256.     /** @private {?shaka.util.ContentSteeringManager} */
  257.     this.contentSteeringManager_ = null;
  259.     /** @private {boolean} */
  260.     this.needsClosedCaptionsDetection_ = true;
  262.     /** @private {Set.<string>} */
  263.     this.dateRangeIdsEmitted_ = new Set();
  265.     /** @private {shaka.util.EventManager} */
  266.     this.eventManager_ = new shaka.util.EventManager();
  268.     /** @private {HTMLMediaElement} */
  269.     this.mediaElement_ = null;
  270.   }
  273.   /**
  274.    * @override
  275.    * @exportInterface
  276.    */
  277.   configure(config) {
  278.     this.config_ = config;
  280.     if (this.contentSteeringManager_) {
  281.       this.contentSteeringManager_.configure(this.config_);
  282.     }
  283.   }
  285.   /**
  286.    * @override
  287.    * @exportInterface
  288.    */
  289.   async start(uri, playerInterface) {
  290.     goog.asserts.assert(this.config_, 'Must call configure() before start()!');
  291.     this.playerInterface_ = playerInterface;
  292.     this.lowLatencyMode_ = playerInterface.isLowLatencyMode();
  294.     const response = await this.requestManifest_([uri]);
  296.     // Record the master playlist URI after redirects.
  297.     this.masterPlaylistUri_ = response.uri;
  299.     goog.asserts.assert(response.data, 'Response data should be non-null!');
  300.     await this.parseManifest_(response.data, uri);
  302.     goog.asserts.assert(this.manifest_, 'Manifest should be non-null');
  303.     return this.manifest_;
  304.   }
  306.   /**
  307.    * @override
  308.    * @exportInterface
  309.    */
  310.   stop() {
  311.     // Make sure we don't update the manifest again. Even if the timer is not
  312.     // running, this is safe to call.
  313.     if (this.updatePlaylistTimer_) {
  314.       this.updatePlaylistTimer_.stop();
  315.       this.updatePlaylistTimer_ = null;
  316.     }
  318.     /** @type {!Array.<!Promise>} */
  319.     const pending = [];
  321.     if (this.operationManager_) {
  322.       pending.push(this.operationManager_.destroy());
  323.       this.operationManager_ = null;
  324.     }
  326.     this.playerInterface_ = null;
  327.     this.config_ = null;
  328.     this.variantUriSet_.clear();
  329.     this.manifest_ = null;
  330.     this.uriToStreamInfosMap_.clear();
  331.     this.groupIdToStreamInfosMap_.clear();
  332.     this.groupIdToCodecsMap_.clear();
  333.     this.globalVariables_.clear();
  334.     this.mapTagToInitSegmentRefMap_.clear();
  335.     this.aesKeyInfoMap_.clear();
  336.     this.aesKeyMap_.clear();
  337.     this.identityKeyMap_.clear();
  338.     this.identityKidMap_.clear();
  339.     this.dateRangeIdsEmitted_.clear();
  341.     if (this.contentSteeringManager_) {
  342.       this.contentSteeringManager_.destroy();
  343.     }
  345.     if (this.eventManager_) {
  346.       this.eventManager_.release();
  347.       this.eventManager_ = null;
  348.     }
  350.     return Promise.all(pending);
  351.   }
  353.   /**
  354.    * @override
  355.    * @exportInterface
  356.    */
  357.   async update() {
  358.     if (!this.isLive_()) {
  359.       return;
  360.     }
  362.     /** @type {!Array.<!Promise>} */
  363.     const updates = [];
  364.     const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  366.     // This is necessary to calculate correctly the update time.
  367.     this.lastTargetDuration_ = Infinity;
  368.     this.manifest_.gapCount = 0;
  370.     // Only update active streams.
  371.     const activeStreamInfos = streamInfos.filter((s) => s.stream.segmentIndex);
  372.     for (const streamInfo of activeStreamInfos) {
  373.       updates.push(this.updateStream_(streamInfo));
  374.     }
  375.     await Promise.all(updates);
  377.     // Now that streams have been updated, notify the presentation timeline.
  378.     this.notifySegmentsForStreams_(activeStreamInfos.map((s) => s.stream));
  380.     // If any hasEndList is false, the stream is still live.
  381.     const stillLive = activeStreamInfos.some((s) => s.hasEndList == false);
  382.     if (activeStreamInfos.length && !stillLive) {
  383.       // Convert the presentation to VOD and set the duration.
  384.       const PresentationType = shaka.hls.HlsParser.PresentationType_;
  385.       this.setPresentationType_(PresentationType.VOD);
  387.       // The duration is the minimum of the end times of all active streams.
  388.       // Non-active streams are not guaranteed to have useful maxTimestamp
  389.       // values, due to the lazy-loading system, so they are ignored.
  390.       const maxTimestamps = activeStreamInfos.map((s) => s.maxTimestamp);
  391.       // The duration is the minimum of the end times of all streams.
  392.       this.presentationTimeline_.setDuration(Math.min(...maxTimestamps));
  393.       this.playerInterface_.updateDuration();
  394.     }
  395.     if (stillLive) {
  396.       this.determineDuration_();
  397.     }
  398.     // Check if any playlist does not have the first reference (due to a
  399.     // problem in the live encoder for example), and disable the stream if
  400.     // necessary.
  401.     for (const streamInfo of activeStreamInfos) {
  402.       if (streamInfo.stream.segmentIndex &&
  403.           !streamInfo.stream.segmentIndex.earliestReference()) {
  404.         this.playerInterface_.disableStream(streamInfo.stream);
  405.       }
  406.     }
  407.   }
  409.   /**
  410.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  411.    * @return {!Map.<number, number>}
  412.    * @private
  413.    */
  414.   getMediaSequenceToStartTimeFor_(streamInfo) {
  415.     if (this.isLive_()) {
  416.       return this.mediaSequenceToStartTimeByType_.get(streamInfo.type);
  417.     } else {
  418.       return streamInfo.mediaSequenceToStartTime;
  419.     }
  420.   }
  422.   /**
  423.    * Updates a stream.
  424.    *
  425.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  426.    * @return {!Promise}
  427.    * @private
  428.    */
  429.   async updateStream_(streamInfo) {
  430.     const manifestUris = [];
  431.     for (const uri of streamInfo.getUris()) {
  432.       const uriObj = new goog.Uri(uri);
  433.       const queryData = uriObj.getQueryData();
  434.       if (streamInfo.canBlockReload) {
  435.         if (streamInfo.nextMediaSequence >= 0) {
  436.           // Indicates that the server must hold the request until a Playlist
  437.           // contains a Media Segment with Media Sequence
  438.           queryData.add('_HLS_msn', String(streamInfo.nextMediaSequence));
  439.         }
  440.         if (streamInfo.nextPart >= 0) {
  441.           // Indicates, in combination with _HLS_msn, that the server must hold
  442.           // the request until a Playlist contains Partial Segment N of Media
  443.           // Sequence Number M or later.
  444.           queryData.add('_HLS_part', String(streamInfo.nextPart));
  445.         }
  446.       }
  447.       if (streamInfo.canSkipSegments) {
  448.         // Enable delta updates. This will replace older segments with
  449.         // 'EXT-X-SKIP' tag in the media playlist.
  450.         queryData.add('_HLS_skip', 'YES');
  451.       }
  452.       if (queryData.getCount()) {
  453.         uriObj.setQueryData(queryData);
  454.       }
  455.       manifestUris.push(uriObj.toString());
  456.     }
  457.     let response;
  458.     try {
  459.       response =
  460.           await this.requestManifest_(manifestUris, /* isPlaylist= */ true);
  461.     } catch (e) {
  462.       if (this.playerInterface_) {
  463.         this.playerInterface_.disableStream(streamInfo.stream);
  464.       }
  465.       throw e;
  466.     }
  467.     if (!streamInfo.stream.segmentIndex) {
  468.       // The stream was closed since the update was first requested.
  469.       return;
  470.     }
  472.     /** @type {shaka.hls.Playlist} */
  473.     const playlist = this.manifestTextParser_.parsePlaylist(response.data);
  475.     if (playlist.type != shaka.hls.PlaylistType.MEDIA) {
  476.       throw new shaka.util.Error(
  477.           shaka.util.Error.Severity.CRITICAL,
  478.           shaka.util.Error.Category.MANIFEST,
  479.           shaka.util.Error.Code.HLS_INVALID_PLAYLIST_HIERARCHY);
  480.     }
  482.     // Record the final URI after redirects.
  483.     const responseUri = response.uri;
  484.     if (responseUri != response.originalUri &&
  485.         !streamInfo.getUris().includes(responseUri)) {
  486.       streamInfo.redirectUris.push(responseUri);
  487.     }
  489.     /** @type {!Array.<!shaka.hls.Tag>} */
  490.     const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  491.         'EXT-X-DEFINE');
  493.     const mediaVariables = this.parseMediaVariables_(
  494.         variablesTags, responseUri);
  496.     const stream = streamInfo.stream;
  498.     const mediaSequenceToStartTime =
  499.         this.getMediaSequenceToStartTimeFor_(streamInfo);
  500.     const {keyIds, drmInfos} = await this.parseDrmInfo_(
  501.         playlist, stream.mimeType, streamInfo.getUris, mediaVariables);
  503.     const keysAreEqual =
  504.       (a, b) => a.size === b.size && [...a].every((value) => b.has(value));
  506.     if (!keysAreEqual(stream.keyIds, keyIds)) {
  507.       stream.keyIds = keyIds;
  508.       stream.drmInfos = drmInfos;
  509.       this.playerInterface_.newDrmInfo(stream);
  510.     }
  512.     const {segments, bandwidth} = this.createSegments_(
  513.         playlist, mediaSequenceToStartTime, mediaVariables,
  514.         streamInfo.getUris, streamInfo.type);
  515.     if (bandwidth) {
  516.       stream.bandwidth = bandwidth;
  517.     }
  519.     const qualityInfo =
  520.         shaka.media.QualityObserver.createQualityInfo(stream);
  521.     for (const segment of segments) {
  522.       if (segment.initSegmentReference) {
  523.         segment.initSegmentReference.mediaQuality = qualityInfo;
  524.       }
  525.     }
  527.     stream.segmentIndex.mergeAndEvict(
  528.         segments, this.presentationTimeline_.getSegmentAvailabilityStart());
  529.     if (segments.length) {
  530.       const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  531.           playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  532.       const skipTag = shaka.hls.Utils.getFirstTagWithName(
  533.           playlist.tags, 'EXT-X-SKIP');
  534.       const skippedSegments =
  535.           skipTag ? Number(skipTag.getAttributeValue('SKIPPED-SEGMENTS')) : 0;
  536.       const {nextMediaSequence, nextPart} =
  537.           this.getNextMediaSequenceAndPart_(mediaSequenceNumber, segments);
  538.       streamInfo.nextMediaSequence = nextMediaSequence + skippedSegments;
  539.       streamInfo.nextPart = nextPart;
  540.       const playlistStartTime = mediaSequenceToStartTime.get(
  541.           mediaSequenceNumber);
  542.       stream.segmentIndex.evict(playlistStartTime);
  543.     }
  544.     const oldSegment = stream.segmentIndex.earliestReference();
  545.     if (oldSegment) {
  546.       streamInfo.minTimestamp = oldSegment.startTime;
  548.       const newestSegment = segments[segments.length - 1];
  549.       goog.asserts.assert(newestSegment, 'Should have segments!');
  551.       streamInfo.maxTimestamp = newestSegment.endTime;
  552.     }
  554.     // Once the last segment has been added to the playlist,
  555.     // #EXT-X-ENDLIST tag will be appended.
  556.     // If that happened, treat the rest of the EVENT presentation as VOD.
  557.     const endListTag =
  558.         shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-ENDLIST');
  560.     if (endListTag) {
  561.       // Flag this for later.  We don't convert the whole presentation into VOD
  562.       // until we've seen the ENDLIST tag for all active playlists.
  563.       streamInfo.hasEndList = true;
  564.     }
  566.     this.determineLastTargetDuration_(playlist);
  568.     this.processDateRangeTags_(
  569.         playlist.tags, stream.type, mediaVariables, streamInfo.getUris);
  570.   }
  573.   /**
  574.    * @override
  575.    * @exportInterface
  576.    */
  577.   onExpirationUpdated(sessionId, expiration) {
  578.     // No-op
  579.   }
  581.   /**
  582.    * @override
  583.    * @exportInterface
  584.    */
  585.   onInitialVariantChosen(variant) {
  586.     // No-op
  587.   }
  589.   /**
  590.    * @override
  591.    * @exportInterface
  592.    */
  593.   banLocation(uri) {
  594.     if (this.contentSteeringManager_) {
  595.       this.contentSteeringManager_.banLocation(uri);
  596.     }
  597.   }
  599.   /**
  600.    * @override
  601.    * @exportInterface
  602.    */
  603.   setMediaElement(mediaElement) {
  604.     this.mediaElement_ = mediaElement;
  605.   }
  607.   /**
  608.    * Align the streams by sequence number by dropping early segments.  Then
  609.    * offset the streams to begin at presentation time 0.
  610.    * @param {!Array.<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  611.    * @private
  612.    */
  613.   syncStreamsWithSequenceNumber_(streamInfos) {
  614.     // We assume that, when this is first called, we have enough info to
  615.     // determine how to use the program date times (e.g. we have both a video
  616.     // and an audio, and all other videos and audios match those).
  617.     // Thus, we only need to calculate this once.
  618.     const updateMinSequenceNumber = this.minSequenceNumber_ == -1;
  619.     // Sync using media sequence number.  Find the highest starting sequence
  620.     // number among all streams.  Later, we will drop any references to
  621.     // earlier segments in other streams, then offset everything back to 0.
  622.     for (const streamInfo of streamInfos) {
  623.       const segmentIndex = streamInfo.stream.segmentIndex;
  624.       goog.asserts.assert(segmentIndex,
  625.           'Only loaded streams should be synced');
  626.       const mediaSequenceToStartTime =
  627.           this.getMediaSequenceToStartTimeFor_(streamInfo);
  628.       const segment0 = segmentIndex.earliestReference();
  629.       if (segment0) {
  630.         // This looks inefficient, but iteration order is insertion order.
  631.         // So the very first entry should be the one we want.
  632.         // We assert that this holds true so that we are alerted by debug
  633.         // builds and tests if it changes.  We still do a loop, though, so
  634.         // that the code functions correctly in production no matter what.
  635.         if (goog.DEBUG) {
  636.           const firstSequenceStartTime =
  637.               mediaSequenceToStartTime.values().next().value;
  638.           if (firstSequenceStartTime != segment0.startTime) {
  639.             shaka.log.warning(
  640.                 'Sequence number map is not ordered as expected!');
  641.           }
  642.         }
  643.         for (const [sequence, start] of mediaSequenceToStartTime) {
  644.           if (start == segment0.startTime) {
  645.             if (updateMinSequenceNumber) {
  646.               this.minSequenceNumber_ = Math.max(
  647.                   this.minSequenceNumber_, sequence);
  648.             }
  649.             // Even if we already have decided on a value for
  650.             // |this.minSequenceNumber_|, we still need to determine the first
  651.             // sequence number for the stream, to offset it in the code below.
  652.             streamInfo.firstSequenceNumber = sequence;
  653.             break;
  654.           }
  655.         }
  656.       }
  657.     }
  659.     if (this.minSequenceNumber_ < 0) {
  660.       // Nothing to sync.
  661.       return;
  662.     }
  664.     shaka.log.debug('Syncing HLS streams against base sequence number:',
  665.         this.minSequenceNumber_);
  667.     for (const streamInfo of streamInfos) {
  668.       if (!this.ignoreManifestProgramDateTimeFor_(streamInfo.type)) {
  669.         continue;
  670.       }
  671.       const segmentIndex = streamInfo.stream.segmentIndex;
  672.       if (segmentIndex) {
  673.         // Drop any earlier references.
  674.         const numSegmentsToDrop =
  675.             this.minSequenceNumber_ - streamInfo.firstSequenceNumber;
  676.         if (numSegmentsToDrop > 0) {
  677.           segmentIndex.dropFirstReferences(numSegmentsToDrop);
  679.           // Now adjust timestamps back to begin at 0.
  680.           const segmentN = segmentIndex.earliestReference();
  681.           if (segmentN) {
  682.             const streamOffset = -segmentN.startTime;
  683.             // Modify all SegmentReferences equally.
  684.             streamInfo.stream.segmentIndex.offset(streamOffset);
  685.             // Update other parts of streamInfo the same way.
  686.             this.offsetStreamInfo_(streamInfo, streamOffset);
  687.           }
  688.         }
  689.       }
  690.     }
  691.   }
  693.   /**
  694.    * Synchronize streams by the EXT-X-PROGRAM-DATE-TIME tags attached to their
  695.    * segments.  Also normalizes segment times so that the earliest segment in
  696.    * any stream is at time 0.
  697.    * @param {!Array.<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  698.    * @private
  699.    */
  700.   syncStreamsWithProgramDateTime_(streamInfos) {
  701.     // We assume that, when this is first called, we have enough info to
  702.     // determine how to use the program date times (e.g. we have both a video
  703.     // and an audio, and all other videos and audios match those).
  704.     // Thus, we only need to calculate this once.
  705.     if (this.lowestSyncTime_ == Infinity) {
  706.       for (const streamInfo of streamInfos) {
  707.         const segmentIndex = streamInfo.stream.segmentIndex;
  708.         goog.asserts.assert(segmentIndex,
  709.             'Only loaded streams should be synced');
  710.         const segment0 = segmentIndex.earliestReference();
  711.         if (segment0 != null && segment0.syncTime != null) {
  712.           this.lowestSyncTime_ =
  713.               Math.min(this.lowestSyncTime_, segment0.syncTime);
  714.         }
  715.       }
  716.     }
  718.     const lowestSyncTime = this.lowestSyncTime_;
  719.     if (lowestSyncTime == Infinity) {
  720.       // Nothing to sync.
  721.       return;
  722.     }
  724.     shaka.log.debug('Syncing HLS streams against base time:', lowestSyncTime);
  726.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  727.       if (this.ignoreManifestProgramDateTimeFor_(streamInfo.type)) {
  728.         continue;
  729.       }
  730.       const segmentIndex = streamInfo.stream.segmentIndex;
  731.       if (segmentIndex != null) {
  732.         // A segment's startTime should be based on its syncTime vs the lowest
  733.         // syncTime across all streams.  The earliest segment sync time from
  734.         // any stream will become presentation time 0.  If two streams start
  735.         // e.g. 6 seconds apart in syncTime, then their first segments will
  736.         // also start 6 seconds apart in presentation time.
  738.         const segment0 = segmentIndex.earliestReference();
  739.         if (!segment0) {
  740.           continue;
  741.         }
  742.         if (segment0.syncTime == null) {
  743.           shaka.log.alwaysError('Missing EXT-X-PROGRAM-DATE-TIME for stream',
  744.               streamInfo.getUris(),
  745.               'Expect AV sync issues!');
  746.         } else {
  747.           // Stream metadata are offset by a fixed amount based on the
  748.           // first segment.
  749.           const segment0TargetTime = segment0.syncTime - lowestSyncTime;
  750.           const streamOffset = segment0TargetTime - segment0.startTime;
  751.           this.offsetStreamInfo_(streamInfo, streamOffset);
  753.           // This is computed across all segments separately to manage
  754.           // accumulated drift in durations.
  755.           for (const segment of segmentIndex) {
  756.             segment.syncAgainst(lowestSyncTime);
  757.           }
  758.         }
  759.       }
  760.     }
  761.   }
  763.   /**
  764.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  765.    * @param {number} offset
  766.    * @private
  767.    */
  768.   offsetStreamInfo_(streamInfo, offset) {
  769.     // Adjust our accounting of the minimum timestamp.
  770.     streamInfo.minTimestamp += offset;
  772.     // Adjust our accounting of the maximum timestamp.
  773.     streamInfo.maxTimestamp += offset;
  774.     goog.asserts.assert(streamInfo.maxTimestamp >= 0,
  775.         'Negative maxTimestamp after adjustment!');
  777.     // Update our map from sequence number to start time.
  778.     const mediaSequenceToStartTime =
  779.         this.getMediaSequenceToStartTimeFor_(streamInfo);
  780.     for (const [key, value] of mediaSequenceToStartTime) {
  781.       mediaSequenceToStartTime.set(key, value + offset);
  782.     }
  784.     shaka.log.debug('Offset', offset, 'applied to',
  785.         streamInfo.getUris());
  786.   }
  788.   /**
  789.    * Parses the manifest.
  790.    *
  791.    * @param {BufferSource} data
  792.    * @param {string} uri
  793.    * @return {!Promise}
  794.    * @private
  795.    */
  796.   async parseManifest_(data, uri) {
  797.     const Utils = shaka.hls.Utils;
  798.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  800.     goog.asserts.assert(this.masterPlaylistUri_,
  801.         'Master playlist URI must be set before calling parseManifest_!');
  803.     const playlist = this.manifestTextParser_.parsePlaylist(data);
  805.     /** @type {!Array.<!shaka.hls.Tag>} */
  806.     const variablesTags = Utils.filterTagsByName(playlist.tags, 'EXT-X-DEFINE');
  808.     /** @type {!Array.<!shaka.extern.Variant>} */
  809.     let variants = [];
  810.     /** @type {!Array.<!shaka.extern.Stream>} */
  811.     let textStreams = [];
  812.     /** @type {!Array.<!shaka.extern.Stream>} */
  813.     let imageStreams = [];
  815.     // This assert is our own sanity check.
  816.     goog.asserts.assert(this.presentationTimeline_ == null,
  817.         'Presentation timeline created early!');
  818.     // We don't know if the presentation is VOD or live until we parse at least
  819.     // one media playlist, so make a VOD-style presentation timeline for now
  820.     // and change the type later if we discover this is live.
  821.     // Since the player will load the first variant chosen early in the process,
  822.     // there isn't a window during playback where the live-ness is unknown.
  823.     this.presentationTimeline_ = new shaka.media.PresentationTimeline(
  824.         /* presentationStartTime= */ null, /* delay= */ 0);
  825.     this.presentationTimeline_.setStatic(true);
  827.     const getUris = () => {
  828.       return [uri];
  829.     };
  831.     /** @type {?string} */
  832.     let mediaPlaylistType = null;
  834.     /** @type {!Map.<string, string>} */
  835.     let mediaVariables = new Map();
  837.     // Parsing a media playlist results in a single-variant stream.
  838.     if (playlist.type == shaka.hls.PlaylistType.MEDIA) {
  839.       this.needsClosedCaptionsDetection_ = false;
  841.       /** @type {!Array.<!shaka.hls.Tag>} */
  842.       const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  843.           'EXT-X-DEFINE');
  845.       mediaVariables = this.parseMediaVariables_(
  846.           variablesTags, this.masterPlaylistUri_);
  848.       // By default we assume it is video, but in a later step the correct type
  849.       // is obtained.
  850.       mediaPlaylistType = ContentType.VIDEO;
  852.       // These values can be obtained later so these default values are good.
  853.       const codecs = '';
  854.       const languageValue = '';
  855.       const channelsCount = null;
  856.       const sampleRate = null;
  857.       const closedCaptions = new Map();
  858.       const spatialAudio = false;
  859.       const characteristics = null;
  860.       const forced = false; // Only relevant for text.
  861.       const primary = true; // This is the only stream!
  862.       const name = 'Media Playlist';
  864.       // Make the stream info, with those values.
  865.       const streamInfo = await this.convertParsedPlaylistIntoStreamInfo_(
  866.           this.globalId_++, mediaVariables, playlist, getUris, uri, codecs,
  867.           mediaPlaylistType, languageValue, primary, name, channelsCount,
  868.           closedCaptions, characteristics, forced, sampleRate, spatialAudio);
  869.       this.uriToStreamInfosMap_.set(uri, streamInfo);
  872.       if (streamInfo.stream) {
  873.         const qualityInfo =
  874.             shaka.media.QualityObserver.createQualityInfo(streamInfo.stream);
  875.         streamInfo.stream.segmentIndex.forEachTopLevelReference(
  876.             (reference) => {
  877.               if (reference.initSegmentReference) {
  878.                 reference.initSegmentReference.mediaQuality = qualityInfo;
  879.               }
  880.             });
  881.       }
  883.       mediaPlaylistType = streamInfo.stream.type;
  885.       // Wrap the stream from that stream info with a variant.
  886.       variants.push({
  887.         id: 0,
  888.         language: this.getLanguage_(languageValue),
  889.         disabledUntilTime: 0,
  890.         primary: true,
  891.         audio: mediaPlaylistType == 'audio' ? streamInfo.stream : null,
  892.         video: mediaPlaylistType == 'video' ? streamInfo.stream : null,
  893.         bandwidth: streamInfo.stream.bandwidth || 0,
  894.         allowedByApplication: true,
  895.         allowedByKeySystem: true,
  896.         decodingInfos: [],
  897.       });
  898.     } else {
  899.       this.parseMasterVariables_(variablesTags);
  901.       /** @type {!Array.<!shaka.hls.Tag>} */
  902.       const mediaTags = Utils.filterTagsByName(
  903.           playlist.tags, 'EXT-X-MEDIA');
  904.       /** @type {!Array.<!shaka.hls.Tag>} */
  905.       const variantTags = Utils.filterTagsByName(
  906.           playlist.tags, 'EXT-X-STREAM-INF');
  907.       /** @type {!Array.<!shaka.hls.Tag>} */
  908.       const imageTags = Utils.filterTagsByName(
  909.           playlist.tags, 'EXT-X-IMAGE-STREAM-INF');
  910.       /** @type {!Array.<!shaka.hls.Tag>} */
  911.       const iFrameTags = Utils.filterTagsByName(
  912.           playlist.tags, 'EXT-X-I-FRAME-STREAM-INF');
  913.       /** @type {!Array.<!shaka.hls.Tag>} */
  914.       const sessionKeyTags = Utils.filterTagsByName(
  915.           playlist.tags, 'EXT-X-SESSION-KEY');
  916.       /** @type {!Array.<!shaka.hls.Tag>} */
  917.       const sessionDataTags = Utils.filterTagsByName(
  918.           playlist.tags, 'EXT-X-SESSION-DATA');
  919.       /** @type {!Array.<!shaka.hls.Tag>} */
  920.       const contentSteeringTags = Utils.filterTagsByName(
  921.           playlist.tags, 'EXT-X-CONTENT-STEERING');
  923.       this.processSessionData_(sessionDataTags);
  924.       await this.processContentSteering_(contentSteeringTags);
  926.       this.parseCodecs_(variantTags);
  928.       this.parseClosedCaptions_(mediaTags);
  929.       variants = await this.createVariantsForTags_(
  930.           variantTags, sessionKeyTags, mediaTags, getUris,
  931.           this.globalVariables_);
  932.       textStreams = this.parseTexts_(mediaTags);
  933.       imageStreams = await this.parseImages_(imageTags, iFrameTags);
  934.     }
  936.     // Make sure that the parser has not been destroyed.
  937.     if (!this.playerInterface_) {
  938.       throw new shaka.util.Error(
  939.           shaka.util.Error.Severity.CRITICAL,
  940.           shaka.util.Error.Category.PLAYER,
  941.           shaka.util.Error.Code.OPERATION_ABORTED);
  942.     }
  944.     // Single-variant streams aren't lazy-loaded, so for them we already have
  945.     // enough info here to determine the presentation type and duration.
  946.     if (playlist.type == shaka.hls.PlaylistType.MEDIA) {
  947.       if (this.isLive_()) {
  948.         this.changePresentationTimelineToLive_(playlist);
  949.         const delay = this.getUpdatePlaylistDelay_();
  950.         this.updatePlaylistTimer_.tickAfter(/* seconds= */ delay);
  951.       }
  952.       const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  953.       this.finalizeStreams_(streamInfos);
  954.       this.determineDuration_();
  956.       goog.asserts.assert(mediaPlaylistType,
  957.           'mediaPlaylistType should be non-null');
  958.       this.processDateRangeTags_(
  959.           playlist.tags, mediaPlaylistType, mediaVariables, getUris);
  960.     }
  962.     this.manifest_ = {
  963.       presentationTimeline: this.presentationTimeline_,
  964.       variants,
  965.       textStreams,
  966.       imageStreams,
  967.       offlineSessionIds: [],
  968.       minBufferTime: 0,
  969.       sequenceMode: this.config_.hls.sequenceMode,
  970.       ignoreManifestTimestampsInSegmentsMode:
  971.         this.config_.hls.ignoreManifestTimestampsInSegmentsMode,
  972.       type: shaka.media.ManifestParser.HLS,
  973.       serviceDescription: null,
  974.       nextUrl: null,
  975.       periodCount: 1,
  976.       gapCount: 0,
  977.       isLowLatency: false,
  978.     };
  980.     // If there is no 'CODECS' attribute in the manifest and codec guessing is
  981.     // disabled, we need to create the segment indexes now so that missing info
  982.     // can be parsed from the media data and added to the stream objects.
  983.     if (!this.codecInfoInManifest_ && this.config_.hls.disableCodecGuessing) {
  984.       const createIndexes = [];
  985.       for (const variant of this.manifest_.variants) {
  986.         if (variant.audio && variant.audio.codecs === '') {
  987.           createIndexes.push(variant.audio.createSegmentIndex());
  988.         }
  989.         if (variant.video && variant.video.codecs === '') {
  990.           createIndexes.push(variant.video.createSegmentIndex());
  991.         }
  992.       }
  994.       await Promise.all(createIndexes);
  995.     }
  997.     this.playerInterface_.makeTextStreamsForClosedCaptions(this.manifest_);
  999.     if (variants.length == 1) {
  1000.       const createSegmentIndexPromises = [];
  1001.       const variant = variants[0];
  1002.       for (const stream of [variant.video, variant.audio]) {
  1003.         if (stream && !stream.segmentIndex) {
  1004.           createSegmentIndexPromises.push(stream.createSegmentIndex());
  1005.         }
  1006.       }
  1007.       if (createSegmentIndexPromises.length > 0) {
  1008.         await Promise.all(createSegmentIndexPromises);
  1009.       }
  1010.     }
  1011.   }
  1013.   /**
  1014.    * @param {!Array.<!shaka.media.SegmentReference>} segments
  1015.    * @return {!Promise.<shaka.media.SegmentUtils.BasicInfo>}
  1016.    * @private
  1017.    */
  1018.   async getBasicInfoFromSegments_(segments) {
  1019.     const HlsParser = shaka.hls.HlsParser;
  1020.     const defaultBasicInfo = shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1021.         this.config_.hls.mediaPlaylistFullMimeType);
  1022.     if (!segments.length) {
  1023.       return defaultBasicInfo;
  1024.     }
  1025.     const {segment, segmentIndex} = this.getAvailableSegment_(segments);
  1026.     const segmentUris = segment.getUris();
  1027.     const segmentUri = segmentUris[0];
  1028.     const parsedUri = new goog.Uri(segmentUri);
  1029.     const extension = parsedUri.getPath().split('.').pop();
  1030.     const rawMimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_[extension];
  1031.     if (rawMimeType) {
  1032.       return shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1033.           rawMimeType);
  1034.     }
  1036.     const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  1038.     let initData = null;
  1039.     let initMimeType = null;
  1040.     const initSegmentRef = segment.initSegmentReference;
  1041.     if (initSegmentRef) {
  1042.       const initSegmentRequest = shaka.util.Networking.createSegmentRequest(
  1043.           initSegmentRef.getUris(), initSegmentRef.getStartByte(),
  1044.           initSegmentRef.getEndByte(), this.config_.retryParameters);
  1045.       const initType =
  1046.           shaka.net.NetworkingEngine.AdvancedRequestType.INIT_SEGMENT;
  1047.       const initResponse = await this.makeNetworkRequest_(
  1048.           initSegmentRequest, requestType, {type: initType});
  1049.       initData = initResponse.data;
  1050.       if (initSegmentRef.aesKey) {
  1051.         initData = await shaka.media.SegmentUtils.aesDecrypt(
  1052.             initData, initSegmentRef.aesKey, 0);
  1053.       }
  1055.       initMimeType = initResponse.headers['content-type'];
  1056.       if (initMimeType) {
  1057.         // Split the MIME type in case the server sent additional parameters.
  1058.         initMimeType = initMimeType.split(';')[0].toLowerCase();
  1059.       }
  1060.     }
  1062.     const segmentRequest = shaka.util.Networking.createSegmentRequest(
  1063.         segment.getUris(), segment.getStartByte(), segment.getEndByte(),
  1064.         this.config_.retryParameters);
  1065.     const type = shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_SEGMENT;
  1066.     const response = await this.makeNetworkRequest_(
  1067.         segmentRequest, requestType, {type});
  1068.     let data = response.data;
  1069.     if (segment.aesKey) {
  1070.       data = await shaka.media.SegmentUtils.aesDecrypt(
  1071.           data, segment.aesKey, segmentIndex);
  1072.     }
  1074.     let contentMimeType = response.headers['content-type'];
  1075.     if (contentMimeType) {
  1076.       // Split the MIME type in case the server sent additional parameters.
  1077.       contentMimeType = contentMimeType.split(';')[0].toLowerCase();
  1078.     }
  1080.     const validMp4Extensions = [
  1081.       'mp4',
  1082.       'mp4a',
  1083.       'm4s',
  1084.       'm4i',
  1085.       'm4a',
  1086.       'm4f',
  1087.       'cmfa',
  1088.       'mp4v',
  1089.       'm4v',
  1090.       'cmfv',
  1091.       'fmp4',
  1092.     ];
  1093.     const validMp4MimeType = [
  1094.       'audio/mp4',
  1095.       'video/mp4',
  1096.       'video/iso.segment',
  1097.     ];
  1099.     if (shaka.util.TsParser.probe(
  1100.         shaka.util.BufferUtils.toUint8(data))) {
  1101.       const basicInfo =
  1102.           shaka.media.SegmentUtils.getBasicInfoFromTs(data);
  1103.       if (basicInfo) {
  1104.         return basicInfo;
  1105.       }
  1106.     } else if (validMp4Extensions.includes(extension) ||
  1107.         validMp4MimeType.includes(contentMimeType) ||
  1108.         (initMimeType && validMp4MimeType.includes(initMimeType))) {
  1109.       const basicInfo = shaka.media.SegmentUtils.getBasicInfoFromMp4(
  1110.           initData, data);
  1111.       if (basicInfo) {
  1112.         return basicInfo;
  1113.       }
  1114.     }
  1115.     if (contentMimeType) {
  1116.       return shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1117.           contentMimeType);
  1118.     }
  1119.     if (initMimeType) {
  1120.       return shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1121.           initMimeType);
  1122.     }
  1123.     return defaultBasicInfo;
  1124.   }
  1126.   /** @private */
  1127.   determineDuration_() {
  1128.     goog.asserts.assert(this.presentationTimeline_,
  1129.         'Presentation timeline not created!');
  1131.     if (this.isLive_()) {
  1132.       // The spec says nothing much about seeking in live content, but Safari's
  1133.       // built-in HLS implementation does not allow it.  Therefore we will set
  1134.       // the availability window equal to the presentation delay.  The player
  1135.       // will be able to buffer ahead three segments, but the seek window will
  1136.       // be zero-sized.
  1137.       const PresentationType = shaka.hls.HlsParser.PresentationType_;
  1139.       if (this.presentationType_ == PresentationType.LIVE) {
  1140.         let segmentAvailabilityDuration = this.getLiveDuration_();
  1142.         // This defaults to the presentation delay, which has the effect of
  1143.         // making the live stream unseekable.  This is consistent with Apple's
  1144.         // HLS implementation.
  1145.         if (this.config_.hls.useSafariBehaviorForLive) {
  1146.           segmentAvailabilityDuration = this.presentationTimeline_.getDelay();
  1147.         }
  1149.         // The app can override that with a longer duration, to allow seeking.
  1150.         if (!isNaN(this.config_.availabilityWindowOverride)) {
  1151.           segmentAvailabilityDuration = this.config_.availabilityWindowOverride;
  1152.         }
  1154.         this.presentationTimeline_.setSegmentAvailabilityDuration(
  1155.             segmentAvailabilityDuration);
  1156.       }
  1157.     } else {
  1158.       // Use the minimum duration as the presentation duration.
  1159.       this.presentationTimeline_.setDuration(this.getMinDuration_());
  1160.     }
  1162.     if (!this.presentationTimeline_.isStartTimeLocked()) {
  1163.       for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  1164.         if (!streamInfo.stream.segmentIndex) {
  1165.           continue; // Not active.
  1166.         }
  1167.         if (streamInfo.type != 'audio' && streamInfo.type != 'video') {
  1168.           continue;
  1169.         }
  1170.         const firstReference = streamInfo.stream.segmentIndex.get(0);
  1171.         if (firstReference && firstReference.syncTime) {
  1172.           const syncTime = firstReference.syncTime;
  1173.           this.presentationTimeline_.setInitialProgramDateTime(syncTime);
  1174.         }
  1175.       }
  1176.     }
  1178.     // This is the first point where we have a meaningful presentation start
  1179.     // time, and we need to tell PresentationTimeline that so that it can
  1180.     // maintain consistency from here on.
  1181.     this.presentationTimeline_.lockStartTime();
  1183.     // This asserts that the live edge is being calculated from segment times.
  1184.     // For VOD and event streams, this check should still pass.
  1185.     goog.asserts.assert(
  1186.         !this.presentationTimeline_.usingPresentationStartTime(),
  1187.         'We should not be using the presentation start time in HLS!');
  1188.   }
  1190.   /**
  1191.    * Get the variables of each variant tag, and store in a map.
  1192.    * @param {!Array.<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1193.    * @private
  1194.    */
  1195.   parseMasterVariables_(tags) {
  1196.     const queryParams = new goog.Uri(this.masterPlaylistUri_).getQueryData();
  1197.     for (const variableTag of tags) {
  1198.       const name = variableTag.getAttributeValue('NAME');
  1199.       const value = variableTag.getAttributeValue('VALUE');
  1200.       const queryParam = variableTag.getAttributeValue('QUERYPARAM');
  1201.       if (name && value) {
  1202.         if (!this.globalVariables_.has(name)) {
  1203.           this.globalVariables_.set(name, value);
  1204.         }
  1205.       }
  1206.       if (queryParam) {
  1207.         const queryParamValue = queryParams.get(queryParam)[0];
  1208.         if (queryParamValue && !this.globalVariables_.has(queryParamValue)) {
  1209.           this.globalVariables_.set(queryParam, queryParamValue);
  1210.         }
  1211.       }
  1212.     }
  1213.   }
  1215.   /**
  1216.    * Get the variables of each variant tag, and store in a map.
  1217.    * @param {!Array.<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1218.    * @param {string} uri Media playlist URI.
  1219.    * @return {!Map.<string, string>}
  1220.    * @private
  1221.    */
  1222.   parseMediaVariables_(tags, uri) {
  1223.     const queryParams = new goog.Uri(uri).getQueryData();
  1224.     const mediaVariables = new Map();
  1225.     for (const variableTag of tags) {
  1226.       const name = variableTag.getAttributeValue('NAME');
  1227.       const value = variableTag.getAttributeValue('VALUE');
  1228.       const queryParam = variableTag.getAttributeValue('QUERYPARAM');
  1229.       const mediaImport = variableTag.getAttributeValue('IMPORT');
  1230.       if (name && value) {
  1231.         if (!mediaVariables.has(name)) {
  1232.           mediaVariables.set(name, value);
  1233.         }
  1234.       }
  1235.       if (queryParam) {
  1236.         const queryParamValue = queryParams.get(queryParam)[0];
  1237.         if (queryParamValue && !mediaVariables.has(queryParamValue)) {
  1238.           mediaVariables.set(queryParam, queryParamValue);
  1239.         }
  1240.       }
  1241.       if (mediaImport) {
  1242.         const globalValue = this.globalVariables_.get(mediaImport);
  1243.         if (globalValue) {
  1244.           mediaVariables.set(mediaImport, globalValue);
  1245.         }
  1246.       }
  1247.     }
  1248.     return mediaVariables;
  1249.   }
  1251.   /**
  1252.    * Get the codecs of each variant tag, and store in a map from
  1253.    * audio/video/subtitle group id to the codecs arraylist.
  1254.    * @param {!Array.<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1255.    * @private
  1256.    */
  1257.   parseCodecs_(tags) {
  1258.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1260.     for (const variantTag of tags) {
  1261.       const audioGroupId = variantTag.getAttributeValue('AUDIO');
  1262.       const videoGroupId = variantTag.getAttributeValue('VIDEO');
  1263.       const subGroupId = variantTag.getAttributeValue('SUBTITLES');
  1264.       const allCodecs = this.getCodecsForVariantTag_(variantTag);
  1266.       if (subGroupId) {
  1267.         const textCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1268.             ContentType.TEXT, allCodecs);
  1269.         goog.asserts.assert(textCodecs != null, 'Text codecs should be valid.');
  1270.         this.groupIdToCodecsMap_.set(subGroupId, textCodecs);
  1271.         shaka.util.ArrayUtils.remove(allCodecs, textCodecs);
  1272.       }
  1273.       if (audioGroupId) {
  1274.         let codecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1275.             ContentType.AUDIO, allCodecs);
  1276.         if (!codecs) {
  1277.           codecs = this.config_.hls.defaultAudioCodec;
  1278.         }
  1279.         this.groupIdToCodecsMap_.set(audioGroupId, codecs);
  1280.       }
  1281.       if (videoGroupId) {
  1282.         let codecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1283.             ContentType.VIDEO, allCodecs);
  1284.         if (!codecs) {
  1285.           codecs = this.config_.hls.defaultVideoCodec;
  1286.         }
  1287.         this.groupIdToCodecsMap_.set(videoGroupId, codecs);
  1288.       }
  1289.     }
  1290.   }
  1292.   /**
  1293.    * Process EXT-X-SESSION-DATA tags.
  1294.    *
  1295.    * @param {!Array.<!shaka.hls.Tag>} tags
  1296.    * @private
  1297.    */
  1298.   processSessionData_(tags) {
  1299.     for (const tag of tags) {
  1300.       const id = tag.getAttributeValue('DATA-ID');
  1301.       const uri = tag.getAttributeValue('URI');
  1302.       const language = tag.getAttributeValue('LANGUAGE');
  1303.       const value = tag.getAttributeValue('VALUE');
  1304.       const data = (new Map()).set('id', id);
  1305.       if (uri) {
  1306.         data.set('uri', shaka.hls.Utils.constructSegmentUris(
  1307.             [this.masterPlaylistUri_], uri, this.globalVariables_)[0]);
  1308.       }
  1309.       if (language) {
  1310.         data.set('language', language);
  1311.       }
  1312.       if (value) {
  1313.         data.set('value', value);
  1314.       }
  1315.       const event = new shaka.util.FakeEvent('sessiondata', data);
  1316.       if (this.playerInterface_) {
  1317.         this.playerInterface_.onEvent(event);
  1318.       }
  1319.     }
  1320.   }
  1322.   /**
  1323.    * Process EXT-X-CONTENT-STEERING tags.
  1324.    *
  1325.    * @param {!Array.<!shaka.hls.Tag>} tags
  1326.    * @return {!Promise}
  1327.    * @private
  1328.    */
  1329.   async processContentSteering_(tags) {
  1330.     if (!this.playerInterface_ || !this.config_) {
  1331.       return;
  1332.     }
  1333.     let contentSteeringPromise;
  1334.     for (const tag of tags) {
  1335.       const defaultPathwayId = tag.getAttributeValue('PATHWAY-ID');
  1336.       const uri = tag.getAttributeValue('SERVER-URI');
  1337.       if (!defaultPathwayId || !uri) {
  1338.         continue;
  1339.       }
  1340.       this.contentSteeringManager_ =
  1341.             new shaka.util.ContentSteeringManager(this.playerInterface_);
  1342.       this.contentSteeringManager_.configure(this.config_);
  1343.       this.contentSteeringManager_.setBaseUris([this.masterPlaylistUri_]);
  1344.       this.contentSteeringManager_.setManifestType(
  1345.           shaka.media.ManifestParser.HLS);
  1346.       this.contentSteeringManager_.setDefaultPathwayId(defaultPathwayId);
  1347.       contentSteeringPromise =
  1348.           this.contentSteeringManager_.requestInfo(uri);
  1349.       break;
  1350.     }
  1351.     await contentSteeringPromise;
  1352.   }
  1354.   /**
  1355.    * Parse Subtitles and Closed Captions from 'EXT-X-MEDIA' tags.
  1356.    * Create text streams for Subtitles, but not Closed Captions.
  1357.    *
  1358.    * @param {!Array.<!shaka.hls.Tag>} mediaTags Media tags from the playlist.
  1359.    * @return {!Array.<!shaka.extern.Stream>}
  1360.    * @private
  1361.    */
  1362.   parseTexts_(mediaTags) {
  1363.     // Create text stream for each Subtitle media tag.
  1364.     const subtitleTags =
  1365.         shaka.hls.Utils.filterTagsByType(mediaTags, 'SUBTITLES');
  1366.     const textStreams = subtitleTags.map((tag) => {
  1367.       const disableText = this.config_.disableText;
  1368.       if (disableText) {
  1369.         return null;
  1370.       }
  1371.       try {
  1372.         return this.createStreamInfoFromMediaTags_([tag], new Map()).stream;
  1373.       } catch (e) {
  1374.         if (this.config_.hls.ignoreTextStreamFailures) {
  1375.           return null;
  1376.         }
  1377.         throw e;
  1378.       }
  1379.     });
  1381.     const type = shaka.util.ManifestParserUtils.ContentType.TEXT;
  1383.     // Set the codecs for text streams.
  1384.     for (const tag of subtitleTags) {
  1385.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  1386.       const codecs = this.groupIdToCodecsMap_.get(groupId);
  1387.       if (codecs) {
  1388.         const textStreamInfos = this.groupIdToStreamInfosMap_.get(groupId);
  1389.         if (textStreamInfos) {
  1390.           for (const textStreamInfo of textStreamInfos) {
  1391.             textStreamInfo.stream.codecs = codecs;
  1392.             textStreamInfo.stream.mimeType =
  1393.                 this.guessMimeTypeBeforeLoading_(type, codecs) ||
  1394.                 this.guessMimeTypeFallback_(type);
  1395.             this.setFullTypeForStream_(textStreamInfo.stream);
  1396.           }
  1397.         }
  1398.       }
  1399.     }
  1401.     // Do not create text streams for Closed captions.
  1402.     return textStreams.filter((s) => s);
  1403.   }
  1405.   /**
  1406.    * @param {!shaka.extern.Stream} stream
  1407.    * @private
  1408.    */
  1409.   setFullTypeForStream_(stream) {
  1410.     const combinations = new Set([shaka.util.MimeUtils.getFullType(
  1411.         stream.mimeType, stream.codecs)]);
  1412.     if (stream.segmentIndex) {
  1413.       stream.segmentIndex.forEachTopLevelReference((reference) => {
  1414.         if (reference.mimeType) {
  1415.           combinations.add(shaka.util.MimeUtils.getFullType(
  1416.               reference.mimeType, stream.codecs));
  1417.         }
  1418.       });
  1419.     }
  1420.     stream.fullMimeTypes = combinations;
  1421.   }
  1423.   /**
  1424.    * @param {!Array.<!shaka.hls.Tag>} imageTags from the playlist.
  1425.    * @param {!Array.<!shaka.hls.Tag>} iFrameTags from the playlist.
  1426.    * @return {!Promise.<!Array.<!shaka.extern.Stream>>}
  1427.    * @private
  1428.    */
  1429.   async parseImages_(imageTags, iFrameTags) {
  1430.     // Create image stream for each image tag.
  1431.     const imageStreamPromises = imageTags.map(async (tag) => {
  1432.       const disableThumbnails = this.config_.disableThumbnails;
  1433.       if (disableThumbnails) {
  1434.         return null;
  1435.       }
  1436.       try {
  1437.         const streamInfo = await this.createStreamInfoFromImageTag_(tag);
  1438.         return streamInfo.stream;
  1439.       } catch (e) {
  1440.         if (this.config_.hls.ignoreImageStreamFailures) {
  1441.           return null;
  1442.         }
  1443.         throw e;
  1444.       }
  1445.     }).concat(iFrameTags.map((tag) => {
  1446.       const disableThumbnails = this.config_.disableThumbnails;
  1447.       if (disableThumbnails) {
  1448.         return null;
  1449.       }
  1450.       try {
  1451.         const streamInfo = this.createStreamInfoFromIframeTag_(tag);
  1452.         if (streamInfo.stream.codecs !== 'mjpg') {
  1453.           return null;
  1454.         }
  1455.         return streamInfo.stream;
  1456.       } catch (e) {
  1457.         if (this.config_.hls.ignoreImageStreamFailures) {
  1458.           return null;
  1459.         }
  1460.         throw e;
  1461.       }
  1462.     }));
  1463.     const imageStreams = await Promise.all(imageStreamPromises);
  1464.     return imageStreams.filter((s) => s);
  1465.   }
  1467.   /**
  1468.    * @param {!Array.<!shaka.hls.Tag>} mediaTags Media tags from the playlist.
  1469.    * @param {!Map.<string, string>} groupIdPathwayIdMapping
  1470.    * @private
  1471.    */
  1472.   createStreamInfosFromMediaTags_(mediaTags, groupIdPathwayIdMapping) {
  1473.     // Filter out subtitles and  media tags without uri.
  1474.     mediaTags = mediaTags.filter((tag) => {
  1475.       const uri = tag.getAttributeValue('URI') || '';
  1476.       const type = tag.getAttributeValue('TYPE');
  1477.       return type != 'SUBTITLES' && uri != '';
  1478.     });
  1480.     const groupedTags = {};
  1481.     for (const tag of mediaTags) {
  1482.       const key = tag.getTagKey(!this.contentSteeringManager_);
  1483.       if (!groupedTags[key]) {
  1484.         groupedTags[key] = [tag];
  1485.       } else {
  1486.         groupedTags[key].push(tag);
  1487.       }
  1488.     }
  1490.     for (const key in groupedTags) {
  1491.       // Create stream info for each audio / video media grouped tag.
  1492.       this.createStreamInfoFromMediaTags_(
  1493.           groupedTags[key], groupIdPathwayIdMapping);
  1494.     }
  1495.   }
  1497.   /**
  1498.    * @param {!Array.<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1499.    * @param {!Array.<!shaka.hls.Tag>} sessionKeyTags EXT-X-SESSION-KEY tags
  1500.    * from the playlist.
  1501.    * @param {!Array.<!shaka.hls.Tag>} mediaTags EXT-X-MEDIA tags from the
  1502.    * playlist.
  1503.    * @param {function():!Array.<string>} getUris
  1504.    * @param {?Map.<string, string>=} variables
  1505.    * @return {!Promise.<!Array.<!shaka.extern.Variant>>}
  1506.    * @private
  1507.    */
  1508.   async createVariantsForTags_(tags, sessionKeyTags, mediaTags, getUris,
  1509.       variables) {
  1510.     // EXT-X-SESSION-KEY processing
  1511.     const drmInfos = [];
  1512.     const keyIds = new Set();
  1513.     if (sessionKeyTags.length > 0) {
  1514.       for (const drmTag of sessionKeyTags) {
  1515.         const method = drmTag.getRequiredAttrValue('METHOD');
  1516.         // According to the HLS spec, KEYFORMAT is optional and implicitly
  1517.         // defaults to "identity".
  1518.         // https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-4.4.4.4
  1519.         const keyFormat =
  1520.             drmTag.getAttributeValue('KEYFORMAT') || 'identity';
  1521.         let drmInfo = null;
  1522.         if (method == 'NONE') {
  1523.           continue;
  1524.         } else if (this.isAesMethod_(method)) {
  1525.           const keyUris = shaka.hls.Utils.constructSegmentUris(
  1526.               getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  1527.           const keyMapKey = keyUris.sort().join('');
  1528.           if (!this.aesKeyMap_.has(keyMapKey)) {
  1529.             const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  1530.             const request = shaka.net.NetworkingEngine.makeRequest(
  1531.                 keyUris, this.config_.retryParameters);
  1532.             const keyResponse = this.makeNetworkRequest_(request, requestType);
  1533.             this.aesKeyMap_.set(keyMapKey, keyResponse);
  1534.           }
  1535.           continue;
  1536.         } else if (keyFormat == 'identity') {
  1537.           // eslint-disable-next-line no-await-in-loop
  1538.           drmInfo = await this.identityDrmParser_(
  1539.               drmTag, /* mimeType= */ '', getUris,
  1540.               /* initSegmentRef= */ null, variables);
  1541.         } else {
  1542.           const drmParser =
  1543.               shaka.hls.HlsParser.KEYFORMATS_TO_DRM_PARSERS_[keyFormat];
  1545.           drmInfo = drmParser ?
  1546.               drmParser(drmTag, /* mimeType= */ '') : null;
  1547.         }
  1548.         if (drmInfo) {
  1549.           if (drmInfo.keyIds) {
  1550.             for (const keyId of drmInfo.keyIds) {
  1551.               keyIds.add(keyId);
  1552.             }
  1553.           }
  1554.           drmInfos.push(drmInfo);
  1555.         } else {
  1556.           shaka.log.warning('Unsupported HLS KEYFORMAT', keyFormat);
  1557.         }
  1558.       }
  1559.     }
  1561.     const groupedTags = {};
  1562.     for (const tag of tags) {
  1563.       const key = tag.getTagKey(!this.contentSteeringManager_);
  1564.       if (!groupedTags[key]) {
  1565.         groupedTags[key] = [tag];
  1566.       } else {
  1567.         groupedTags[key].push(tag);
  1568.       }
  1569.     }
  1571.     const allVariants = [];
  1572.     // Create variants for each group of variant tag.
  1573.     for (const key in groupedTags) {
  1574.       const tags = groupedTags[key];
  1575.       const firstTag = tags[0];
  1577.       const frameRate = firstTag.getAttributeValue('FRAME-RATE');
  1578.       const bandwidth =
  1579.           Number(firstTag.getAttributeValue('AVERAGE-BANDWIDTH')) ||
  1580.           Number(firstTag.getRequiredAttrValue('BANDWIDTH'));
  1582.       const resolution = firstTag.getAttributeValue('RESOLUTION');
  1583.       const [width, height] = resolution ? resolution.split('x') : [null, null];
  1585.       const videoRange = firstTag.getAttributeValue('VIDEO-RANGE');
  1587.       let videoLayout = firstTag.getAttributeValue('REQ-VIDEO-LAYOUT');
  1588.       if (videoLayout && videoLayout.includes(',')) {
  1589.         // If multiple video layout strings are present, pick the first valid
  1590.         // one.
  1591.         const layoutStrings = videoLayout.split(',').filter((layoutString) => {
  1592.           return layoutString == 'CH-STEREO' || layoutString == 'CH-MONO';
  1593.         });
  1594.         videoLayout = layoutStrings[0];
  1595.       }
  1596.       // According to the HLS spec:
  1597.       // By default a video variant is monoscopic, so an attribute
  1598.       // consisting entirely of REQ-VIDEO-LAYOUT="CH-MONO" is unnecessary
  1599.       // and SHOULD NOT be present.
  1600.       videoLayout = videoLayout || 'CH-MONO';
  1602.       const streamInfos = this.createStreamInfosForVariantTags_(tags,
  1603.           mediaTags, resolution, frameRate);
  1605.       goog.asserts.assert(streamInfos.audio.length ||
  1606.           streamInfos.video.length, 'We should have created a stream!');
  1608.       allVariants.push(...this.createVariants_(
  1609.           streamInfos.audio,
  1610.           streamInfos.video,
  1611.           bandwidth,
  1612.           width,
  1613.           height,
  1614.           frameRate,
  1615.           videoRange,
  1616.           videoLayout,
  1617.           drmInfos,
  1618.           keyIds));
  1619.     }
  1620.     return allVariants.filter((variant) => variant != null);
  1621.   }
  1623.   /**
  1624.    * Create audio and video streamInfos from an 'EXT-X-STREAM-INF' tag and its
  1625.    * related media tags.
  1626.    *
  1627.    * @param {!Array.<!shaka.hls.Tag>} tags
  1628.    * @param {!Array.<!shaka.hls.Tag>} mediaTags
  1629.    * @param {?string} resolution
  1630.    * @param {?string} frameRate
  1631.    * @return {!shaka.hls.HlsParser.StreamInfos}
  1632.    * @private
  1633.    */
  1634.   createStreamInfosForVariantTags_(tags, mediaTags, resolution, frameRate) {
  1635.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1637.     /** @type {shaka.hls.HlsParser.StreamInfos} */
  1638.     const res = {
  1639.       audio: [],
  1640.       video: [],
  1641.     };
  1642.     const groupIdPathwayIdMapping = new Map();
  1643.     const globalGroupIds = [];
  1644.     let isAudioGroup = false;
  1645.     let isVideoGroup = false;
  1646.     for (const tag of tags) {
  1647.       const audioGroupId = tag.getAttributeValue('AUDIO');
  1648.       const videoGroupId = tag.getAttributeValue('VIDEO');
  1649.       goog.asserts.assert(audioGroupId == null || videoGroupId == null,
  1650.           'Unexpected: both video and audio described by media tags!');
  1652.       const groupId = audioGroupId || videoGroupId;
  1653.       if (!groupId) {
  1654.         continue;
  1655.       }
  1656.       if (!globalGroupIds.includes(groupId)) {
  1657.         globalGroupIds.push(groupId);
  1658.       }
  1659.       const pathwayId = tag.getAttributeValue('PATHWAY-ID');
  1660.       if (pathwayId) {
  1661.         groupIdPathwayIdMapping.set(groupId, pathwayId);
  1662.       }
  1663.       if (audioGroupId) {
  1664.         isAudioGroup = true;
  1665.       } else if (videoGroupId) {
  1666.         isVideoGroup = true;
  1667.       }
  1668.       // Make an educated guess about the stream type.
  1669.       shaka.log.debug('Guessing stream type for', tag.toString());
  1670.     }
  1671.     if (globalGroupIds.length && mediaTags.length) {
  1672.       const mediaTagsForVariant = mediaTags.filter((tag) => {
  1673.         return globalGroupIds.includes(tag.getRequiredAttrValue('GROUP-ID'));
  1674.       });
  1675.       this.createStreamInfosFromMediaTags_(
  1676.           mediaTagsForVariant, groupIdPathwayIdMapping);
  1677.     }
  1678.     const globalGroupId = globalGroupIds.sort().join(',');
  1679.     const streamInfos =
  1680.         (globalGroupId && this.groupIdToStreamInfosMap_.has(globalGroupId)) ?
  1681.         this.groupIdToStreamInfosMap_.get(globalGroupId) : [];
  1682.     if (isAudioGroup) {
  1683.       res.audio.push(...streamInfos);
  1684.     } else if (isVideoGroup) {
  1685.       res.video.push(...streamInfos);
  1686.     }
  1688.     let type;
  1689.     let ignoreStream = false;
  1691.     // The Microsoft HLS manifest generators will make audio-only variants
  1692.     // that link to their URI both directly and through an audio tag.
  1693.     // In that case, ignore the local URI and use the version in the
  1694.     // AUDIO tag, so you inherit its language.
  1695.     // As an example, see the manifest linked in issue #860.
  1696.     const allStreamUris = tags.map((tag) => tag.getRequiredAttrValue('URI'));
  1697.     const hasSameUri = res.audio.find((audio) => {
  1698.       return audio && audio.getUris().find((uri) => {
  1699.         return allStreamUris.includes(uri);
  1700.       });
  1701.     });
  1703.     /** @type {!Array.<string>} */
  1704.     let allCodecs = this.getCodecsForVariantTag_(tags[0]);
  1705.     const videoCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1706.         ContentType.VIDEO, allCodecs);
  1707.     const audioCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1708.         ContentType.AUDIO, allCodecs);
  1710.     if (audioCodecs && !videoCodecs) {
  1711.       // There are no associated media tags, and there's only audio codec,
  1712.       // and no video codec, so it should be audio.
  1713.       type = ContentType.AUDIO;
  1714.       shaka.log.debug('Guessing audio-only.');
  1715.       ignoreStream = res.audio.length > 0;
  1716.     } else if (!res.audio.length && !res.video.length &&
  1717.         audioCodecs && videoCodecs) {
  1718.       // There are both audio and video codecs, so assume multiplexed content.
  1719.       // Note that the default used when CODECS is missing assumes multiple
  1720.       // (and therefore multiplexed).
  1721.       // Recombine the codec strings into one so that MediaSource isn't
  1722.       // lied to later. (That would trigger an error in Chrome.)
  1723.       shaka.log.debug('Guessing multiplexed audio+video.');
  1724.       type = ContentType.VIDEO;
  1725.       allCodecs = [[videoCodecs, audioCodecs].join(',')];
  1726.     } else if (res.audio.length && hasSameUri) {
  1727.       shaka.log.debug('Guessing audio-only.');
  1728.       type = ContentType.AUDIO;
  1729.       ignoreStream = true;
  1730.     } else if (res.video.length && !res.audio.length) {
  1731.       // There are associated video streams.  Assume this is audio.
  1732.       shaka.log.debug('Guessing audio-only.');
  1733.       type = ContentType.AUDIO;
  1734.     } else {
  1735.       shaka.log.debug('Guessing video-only.');
  1736.       type = ContentType.VIDEO;
  1737.     }
  1739.     if (!ignoreStream) {
  1740.       let language = null;
  1741.       let name = null;
  1742.       let channelsCount = null;
  1743.       let spatialAudio = false;
  1744.       let characteristics = null;
  1745.       let sampleRate = null;
  1746.       if (!streamInfos.length) {
  1747.         const mediaTag = mediaTags.find((tag) => {
  1748.           const uri = tag.getAttributeValue('URI') || '';
  1749.           const type = tag.getAttributeValue('TYPE');
  1750.           const groupId = tag.getRequiredAttrValue('GROUP-ID');
  1751.           return type != 'SUBTITLES' && uri == '' &&
  1752.               globalGroupIds.includes(groupId);
  1753.         });
  1754.         if (mediaTag) {
  1755.           language = mediaTag.getAttributeValue('LANGUAGE');
  1756.           name = mediaTag.getAttributeValue('NAME');
  1757.           channelsCount = this.getChannelsCount_(mediaTag);
  1758.           spatialAudio = this.isSpatialAudio_(mediaTag);
  1759.           characteristics = mediaTag.getAttributeValue('CHARACTERISTICS');
  1760.           sampleRate = this.getSampleRate_(mediaTag);
  1761.         }
  1762.       }
  1763.       const streamInfo = this.createStreamInfoFromVariantTags_(
  1764.           tags, allCodecs, type, language, name, channelsCount,
  1765.           characteristics, sampleRate, spatialAudio);
  1766.       if (globalGroupId) {
  1767.         streamInfo.stream.groupId = globalGroupId;
  1768.       }
  1769.       res[streamInfo.stream.type] = [streamInfo];
  1770.     }
  1771.     return res;
  1772.   }
  1775.   /**
  1776.    * Get the codecs from the 'EXT-X-STREAM-INF' tag.
  1777.    *
  1778.    * @param {!shaka.hls.Tag} tag
  1779.    * @return {!Array.<string>} codecs
  1780.    * @private
  1781.    */
  1782.   getCodecsForVariantTag_(tag) {
  1783.     let codecsString = tag.getAttributeValue('CODECS') || '';
  1785.     const supplementalCodecsString =
  1786.         tag.getAttributeValue('SUPPLEMENTAL-CODECS');
  1788.     this.codecInfoInManifest_ = codecsString.length > 0;
  1790.     if (!this.codecInfoInManifest_ && !this.config_.hls.disableCodecGuessing) {
  1791.       // These are the default codecs to assume if none are specified.
  1792.       const defaultCodecsArray = [];
  1794.       if (!this.config_.disableVideo) {
  1795.         defaultCodecsArray.push(this.config_.hls.defaultVideoCodec);
  1796.       }
  1797.       if (!this.config_.disableAudio) {
  1798.         defaultCodecsArray.push(this.config_.hls.defaultAudioCodec);
  1799.       }
  1801.       codecsString = defaultCodecsArray.join(',');
  1802.     }
  1804.     // Strip out internal whitespace while splitting on commas:
  1805.     /** @type {!Array.<string>} */
  1806.     const codecs = codecsString.split(/\s*,\s*/);
  1808.     if (supplementalCodecsString) {
  1809.       const supplementalCodecs = supplementalCodecsString.split(/\s*,\s*/)
  1810.           .map((codec) => {
  1811.             return codec.split('/')[0];
  1812.           });
  1813.       codecs.push(...supplementalCodecs);
  1814.     }
  1816.     return shaka.media.SegmentUtils.codecsFiltering(codecs);
  1817.   }
  1819.   /**
  1820.    * Get the channel count information for an HLS audio track.
  1821.    * CHANNELS specifies an ordered, "/" separated list of parameters.
  1822.    * If the type is audio, the first parameter will be a decimal integer
  1823.    * specifying the number of independent, simultaneous audio channels.
  1824.    * No other channels parameters are currently defined.
  1825.    *
  1826.    * @param {!shaka.hls.Tag} tag
  1827.    * @return {?number}
  1828.    * @private
  1829.    */
  1830.   getChannelsCount_(tag) {
  1831.     const channels = tag.getAttributeValue('CHANNELS');
  1832.     if (!channels) {
  1833.       return null;
  1834.     }
  1835.     const channelcountstring = channels.split('/')[0];
  1836.     const count = parseInt(channelcountstring, 10);
  1837.     return count;
  1838.   }
  1840.   /**
  1841.    * Get the sample rate information for an HLS audio track.
  1842.    *
  1843.    * @param {!shaka.hls.Tag} tag
  1844.    * @return {?number}
  1845.    * @private
  1846.    */
  1847.   getSampleRate_(tag) {
  1848.     const sampleRate = tag.getAttributeValue('SAMPLE-RATE');
  1849.     if (!sampleRate) {
  1850.       return null;
  1851.     }
  1852.     return parseInt(sampleRate, 10);
  1853.   }
  1855.   /**
  1856.    * Get the spatial audio information for an HLS audio track.
  1857.    * In HLS the channels field indicates the number of audio channels that the
  1858.    * stream has (eg: 2). In the case of Dolby Atmos, the complexity is
  1859.    * expressed with the number of channels followed by the word JOC
  1860.    * (eg: 16/JOC), so 16 would be the number of channels (eg: 7.3.6 layout),
  1861.    * and JOC indicates that the stream has spatial audio.
  1862.    * @see https://developer.apple.com/documentation/http_live_streaming/hls_authoring_specification_for_apple_devices/hls_authoring_specification_for_apple_devices_appendixes
  1863.    *
  1864.    * @param {!shaka.hls.Tag} tag
  1865.    * @return {boolean}
  1866.    * @private
  1867.    */
  1868.   isSpatialAudio_(tag) {
  1869.     const channels = tag.getAttributeValue('CHANNELS');
  1870.     if (!channels) {
  1871.       return false;
  1872.     }
  1873.     return channels.includes('/JOC');
  1874.   }
  1876.   /**
  1877.    * Get the closed captions map information for the EXT-X-STREAM-INF tag, to
  1878.    * create the stream info.
  1879.    * @param {!shaka.hls.Tag} tag
  1880.    * @param {string} type
  1881.    * @return {Map.<string, string>} closedCaptions
  1882.    * @private
  1883.    */
  1884.   getClosedCaptions_(tag, type) {
  1885.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1886.     // The attribute of closed captions is optional, and the value may be
  1887.     // 'NONE'.
  1888.     const closedCaptionsAttr = tag.getAttributeValue('CLOSED-CAPTIONS');
  1890.     // EXT-X-STREAM-INF tags may have CLOSED-CAPTIONS attributes.
  1891.     // The value can be either a quoted-string or an enumerated-string with
  1892.     // the value NONE. If the value is a quoted-string, it MUST match the
  1893.     // value of the GROUP-ID attribute of an EXT-X-MEDIA tag elsewhere in the
  1894.     // Playlist whose TYPE attribute is CLOSED-CAPTIONS.
  1895.     if (type == ContentType.VIDEO ) {
  1896.       if (this.config_.disableText) {
  1897.         this.needsClosedCaptionsDetection_ = false;
  1898.         return null;
  1899.       }
  1900.       if (closedCaptionsAttr) {
  1901.         if (closedCaptionsAttr != 'NONE') {
  1902.           return this.groupIdToClosedCaptionsMap_.get(closedCaptionsAttr);
  1903.         }
  1904.         this.needsClosedCaptionsDetection_ = false;
  1905.       } else if (!closedCaptionsAttr && this.groupIdToClosedCaptionsMap_.size) {
  1906.         for (const key of this.groupIdToClosedCaptionsMap_.keys()) {
  1907.           return this.groupIdToClosedCaptionsMap_.get(key);
  1908.         }
  1909.       }
  1910.     }
  1911.     return null;
  1912.   }
  1914.   /**
  1915.    * Get the normalized language value.
  1916.    *
  1917.    * @param {?string} languageValue
  1918.    * @return {string}
  1919.    * @private
  1920.    */
  1921.   getLanguage_(languageValue) {
  1922.     const LanguageUtils = shaka.util.LanguageUtils;
  1923.     return LanguageUtils.normalize(languageValue || 'und');
  1924.   }
  1926.   /**
  1927.    * Get the type value.
  1928.    * Shaka recognizes the content types 'audio', 'video', 'text', and 'image'.
  1929.    * The HLS 'subtitles' type needs to be mapped to 'text'.
  1930.    * @param {!shaka.hls.Tag} tag
  1931.    * @return {string}
  1932.    * @private
  1933.    */
  1934.   getType_(tag) {
  1935.     let type = tag.getRequiredAttrValue('TYPE').toLowerCase();
  1936.     if (type == 'subtitles') {
  1937.       type = shaka.util.ManifestParserUtils.ContentType.TEXT;
  1938.     }
  1939.     return type;
  1940.   }
  1942.   /**
  1943.    * @param {!Array.<shaka.hls.HlsParser.StreamInfo>} audioInfos
  1944.    * @param {!Array.<shaka.hls.HlsParser.StreamInfo>} videoInfos
  1945.    * @param {number} bandwidth
  1946.    * @param {?string} width
  1947.    * @param {?string} height
  1948.    * @param {?string} frameRate
  1949.    * @param {?string} videoRange
  1950.    * @param {?string} videoLayout
  1951.    * @param {!Array.<shaka.extern.DrmInfo>} drmInfos
  1952.    * @param {!Set.<string>} keyIds
  1953.    * @return {!Array.<!shaka.extern.Variant>}
  1954.    * @private
  1955.    */
  1956.   createVariants_(
  1957.       audioInfos, videoInfos, bandwidth, width, height, frameRate, videoRange,
  1958.       videoLayout, drmInfos, keyIds) {
  1959.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1960.     const DrmUtils = shaka.util.DrmUtils;
  1962.     for (const info of videoInfos) {
  1963.       this.addVideoAttributes_(
  1964.           info.stream, width, height, frameRate, videoRange, videoLayout,
  1965.           /** colorGamut= */ null);
  1966.     }
  1968.     // In case of audio-only or video-only content or the audio/video is
  1969.     // disabled by the config, we create an array of one item containing
  1970.     // a null. This way, the double-loop works for all kinds of content.
  1971.     // NOTE: we currently don't have support for audio-only content.
  1972.     const disableAudio = this.config_.disableAudio;
  1973.     if (!audioInfos.length || disableAudio) {
  1974.       audioInfos = [null];
  1975.     }
  1976.     const disableVideo = this.config_.disableVideo;
  1977.     if (!videoInfos.length || disableVideo) {
  1978.       videoInfos = [null];
  1979.     }
  1981.     const variants = [];
  1982.     for (const audioInfo of audioInfos) {
  1983.       for (const videoInfo of videoInfos) {
  1984.         const audioStream = audioInfo ? audioInfo.stream : null;
  1985.         if (audioStream) {
  1986.           audioStream.drmInfos = drmInfos;
  1987.           audioStream.keyIds = keyIds;
  1988.         }
  1989.         const videoStream = videoInfo ? videoInfo.stream : null;
  1990.         if (videoStream) {
  1991.           videoStream.drmInfos = drmInfos;
  1992.           videoStream.keyIds = keyIds;
  1993.         }
  1994.         if (videoStream && !audioStream) {
  1995.           videoStream.bandwidth = bandwidth;
  1996.         }
  1997.         if (!videoStream && audioStream) {
  1998.           audioStream.bandwidth = bandwidth;
  1999.         }
  2000.         const audioDrmInfos = audioInfo ? audioInfo.stream.drmInfos : null;
  2001.         const videoDrmInfos = videoInfo ? videoInfo.stream.drmInfos : null;
  2002.         const videoStreamUri =
  2003.             videoInfo ? videoInfo.getUris().sort().join(',') : '';
  2004.         const audioStreamUri =
  2005.             audioInfo ? audioInfo.getUris().sort().join(',') : '';
  2006.         const variantUriKey = videoStreamUri + ' - ' + audioStreamUri;
  2008.         if (audioStream && videoStream) {
  2009.           if (!DrmUtils.areDrmCompatible(audioDrmInfos, videoDrmInfos)) {
  2010.             shaka.log.warning(
  2011.                 'Incompatible DRM info in HLS variant.  Skipping.');
  2012.             continue;
  2013.           }
  2014.         }
  2016.         if (this.variantUriSet_.has(variantUriKey)) {
  2017.           // This happens when two variants only differ in their text streams.
  2018.           shaka.log.debug(
  2019.               'Skipping variant which only differs in text streams.');
  2020.           continue;
  2021.         }
  2023.         // Since both audio and video are of the same type, this assertion will
  2024.         // catch certain mistakes at runtime that the compiler would miss.
  2025.         goog.asserts.assert(!audioStream ||
  2026.             audioStream.type == ContentType.AUDIO, 'Audio parameter mismatch!');
  2027.         goog.asserts.assert(!videoStream ||
  2028.             videoStream.type == ContentType.VIDEO, 'Video parameter mismatch!');
  2030.         const variant = {
  2031.           id: this.globalId_++,
  2032.           language: audioStream ? audioStream.language : 'und',
  2033.           disabledUntilTime: 0,
  2034.           primary: (!!audioStream && audioStream.primary) ||
  2035.               (!!videoStream && videoStream.primary),
  2036.           audio: audioStream,
  2037.           video: videoStream,
  2038.           bandwidth,
  2039.           allowedByApplication: true,
  2040.           allowedByKeySystem: true,
  2041.           decodingInfos: [],
  2042.         };
  2044.         variants.push(variant);
  2045.         this.variantUriSet_.add(variantUriKey);
  2046.       }
  2047.     }
  2048.     return variants;
  2049.   }
  2051.   /**
  2052.    * Parses an array of EXT-X-MEDIA tags, then stores the values of all tags
  2053.    * with TYPE="CLOSED-CAPTIONS" into a map of group id to closed captions.
  2054.    *
  2055.    * @param {!Array.<!shaka.hls.Tag>} mediaTags
  2056.    * @private
  2057.    */
  2058.   parseClosedCaptions_(mediaTags) {
  2059.     const closedCaptionsTags =
  2060.         shaka.hls.Utils.filterTagsByType(mediaTags, 'CLOSED-CAPTIONS');
  2061.     this.needsClosedCaptionsDetection_ = closedCaptionsTags.length == 0;
  2062.     for (const tag of closedCaptionsTags) {
  2063.       goog.asserts.assert(tag.name == 'EXT-X-MEDIA',
  2064.           'Should only be called on media tags!');
  2065.       const languageValue = tag.getAttributeValue('LANGUAGE');
  2066.       let language = this.getLanguage_(languageValue);
  2067.       if (!languageValue) {
  2068.         const nameValue = tag.getAttributeValue('NAME');
  2069.         if (nameValue) {
  2070.           language = nameValue;
  2071.         }
  2072.       }
  2074.       // The GROUP-ID value is a quoted-string that specifies the group to which
  2075.       // the Rendition belongs.
  2076.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  2078.       // The value of INSTREAM-ID is a quoted-string that specifies a Rendition
  2079.       // within the segments in the Media Playlist. This attribute is REQUIRED
  2080.       // if the TYPE attribute is CLOSED-CAPTIONS.
  2081.       // We need replace SERVICE string by our internal svc string.
  2082.       const instreamId = tag.getRequiredAttrValue('INSTREAM-ID')
  2083.           .replace('SERVICE', 'svc');
  2084.       if (!this.groupIdToClosedCaptionsMap_.get(groupId)) {
  2085.         this.groupIdToClosedCaptionsMap_.set(groupId, new Map());
  2086.       }
  2087.       this.groupIdToClosedCaptionsMap_.get(groupId).set(instreamId, language);
  2088.     }
  2089.   }
  2091.   /**
  2092.    * Parse EXT-X-MEDIA media tag into a Stream object.
  2093.    *
  2094.    * @param {!Array.<!shaka.hls.Tag>} tags
  2095.    * @param {!Map.<string, string>} groupIdPathwayIdMapping
  2096.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2097.    * @private
  2098.    */
  2099.   createStreamInfoFromMediaTags_(tags, groupIdPathwayIdMapping) {
  2100.     const verbatimMediaPlaylistUris = [];
  2101.     const globalGroupIds = [];
  2102.     const groupIdUriMappping = new Map();
  2103.     for (const tag of tags) {
  2104.       goog.asserts.assert(tag.name == 'EXT-X-MEDIA',
  2105.           'Should only be called on media tags!');
  2106.       const uri = tag.getRequiredAttrValue('URI');
  2107.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  2108.       verbatimMediaPlaylistUris.push(uri);
  2109.       globalGroupIds.push(groupId);
  2110.       groupIdUriMappping.set(groupId, uri);
  2111.     }
  2113.     const globalGroupId = globalGroupIds.sort().join(',');
  2114.     const firstTag = tags[0];
  2115.     let codecs = '';
  2116.     /** @type {string} */
  2117.     const type = this.getType_(firstTag);
  2118.     if (type == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2119.       codecs = firstTag.getAttributeValue('CODECS') || '';
  2120.     } else {
  2121.       for (const groupId of globalGroupIds) {
  2122.         if (this.groupIdToCodecsMap_.has(groupId)) {
  2123.           codecs = this.groupIdToCodecsMap_.get(groupId);
  2124.           break;
  2125.         }
  2126.       }
  2127.     }
  2129.     // Check if the stream has already been created as part of another Variant
  2130.     // and return it if it has.
  2131.     const key = verbatimMediaPlaylistUris.sort().join(',');
  2132.     if (this.uriToStreamInfosMap_.has(key)) {
  2133.       return this.uriToStreamInfosMap_.get(key);
  2134.     }
  2135.     const streamId = this.globalId_++;
  2136.     if (this.contentSteeringManager_) {
  2137.       for (const [groupId, uri] of groupIdUriMappping) {
  2138.         const pathwayId = groupIdPathwayIdMapping.get(groupId);
  2139.         if (pathwayId) {
  2140.           this.contentSteeringManager_.addLocation(streamId, pathwayId, uri);
  2141.         }
  2142.       }
  2143.     }
  2145.     const language = firstTag.getAttributeValue('LANGUAGE');
  2146.     const name = firstTag.getAttributeValue('NAME');
  2148.     // NOTE: According to the HLS spec, "DEFAULT=YES" requires "AUTOSELECT=YES".
  2149.     // However, we don't bother to validate "AUTOSELECT", since we don't
  2150.     // actually use it in our streaming model, and we treat everything as
  2151.     // "AUTOSELECT=YES".  A value of "AUTOSELECT=NO" would imply that it may
  2152.     // only be selected explicitly by the user, and we don't have a way to
  2153.     // represent that in our model.
  2154.     const defaultAttrValue = firstTag.getAttributeValue('DEFAULT');
  2155.     const primary = defaultAttrValue == 'YES';
  2157.     const channelsCount =
  2158.         type == 'audio' ? this.getChannelsCount_(firstTag) : null;
  2159.     const spatialAudio =
  2160.         type == 'audio' ? this.isSpatialAudio_(firstTag) : false;
  2161.     const characteristics = firstTag.getAttributeValue('CHARACTERISTICS');
  2163.     const forcedAttrValue = firstTag.getAttributeValue('FORCED');
  2164.     const forced = forcedAttrValue == 'YES';
  2165.     const sampleRate = type == 'audio' ? this.getSampleRate_(firstTag) : null;
  2166.     // TODO: Should we take into account some of the currently ignored
  2167.     // attributes: INSTREAM-ID, Attribute descriptions: https://bit.ly/2lpjOhj
  2168.     const streamInfo = this.createStreamInfo_(
  2169.         streamId, verbatimMediaPlaylistUris, codecs, type, language,
  2170.         primary, name, channelsCount, /* closedCaptions= */ null,
  2171.         characteristics, forced, sampleRate, spatialAudio);
  2172.     if (streamInfo.stream) {
  2173.       streamInfo.stream.groupId = globalGroupId;
  2174.     }
  2175.     if (this.groupIdToStreamInfosMap_.has(globalGroupId)) {
  2176.       this.groupIdToStreamInfosMap_.get(globalGroupId).push(streamInfo);
  2177.     } else {
  2178.       this.groupIdToStreamInfosMap_.set(globalGroupId, [streamInfo]);
  2179.     }
  2181.     this.uriToStreamInfosMap_.set(key, streamInfo);
  2182.     return streamInfo;
  2183.   }
  2185.   /**
  2186.    * Parse EXT-X-IMAGE-STREAM-INF media tag into a Stream object.
  2187.    *
  2188.    * @param {shaka.hls.Tag} tag
  2189.    * @return {!Promise.<!shaka.hls.HlsParser.StreamInfo>}
  2190.    * @private
  2191.    */
  2192.   async createStreamInfoFromImageTag_(tag) {
  2193.     goog.asserts.assert(tag.name == 'EXT-X-IMAGE-STREAM-INF',
  2194.         'Should only be called on image tags!');
  2195.     /** @type {string} */
  2196.     const type = shaka.util.ManifestParserUtils.ContentType.IMAGE;
  2198.     const verbatimImagePlaylistUri = tag.getRequiredAttrValue('URI');
  2199.     const codecs = tag.getAttributeValue('CODECS', 'jpeg') || '';
  2201.     // Check if the stream has already been created as part of another Variant
  2202.     // and return it if it has.
  2203.     if (this.uriToStreamInfosMap_.has(verbatimImagePlaylistUri)) {
  2204.       return this.uriToStreamInfosMap_.get(verbatimImagePlaylistUri);
  2205.     }
  2207.     const language = tag.getAttributeValue('LANGUAGE');
  2208.     const name = tag.getAttributeValue('NAME');
  2210.     const characteristics = tag.getAttributeValue('CHARACTERISTICS');
  2212.     const streamInfo = this.createStreamInfo_(
  2213.         this.globalId_++, [verbatimImagePlaylistUri], codecs, type, language,
  2214.         /* primary= */ false, name, /* channelsCount= */ null,
  2215.         /* closedCaptions= */ null, characteristics, /* forced= */ false,
  2216.         /* sampleRate= */ null, /* spatialAudio= */ false);
  2218.     // Parse misc attributes.
  2219.     const resolution = tag.getAttributeValue('RESOLUTION');
  2220.     if (resolution) {
  2221.       // The RESOLUTION tag represents the resolution of a single thumbnail, not
  2222.       // of the entire sheet at once (like we expect in the output).
  2223.       // So multiply by the layout size.
  2225.       // Since we need to have generated the segment index for this, we can't
  2226.       // lazy-load in this situation.
  2227.       await streamInfo.stream.createSegmentIndex();
  2229.       const reference = streamInfo.stream.segmentIndex.get(0);
  2230.       const layout = reference.getTilesLayout();
  2231.       if (layout) {
  2232.         streamInfo.stream.width =
  2233.             Number(resolution.split('x')[0]) * Number(layout.split('x')[0]);
  2234.         streamInfo.stream.height =
  2235.             Number(resolution.split('x')[1]) * Number(layout.split('x')[1]);
  2236.         // TODO: What happens if there are multiple grids, with different
  2237.         // layout sizes, inside this image stream?
  2238.       }
  2239.     }
  2240.     const bandwidth = tag.getAttributeValue('BANDWIDTH');
  2241.     if (bandwidth) {
  2242.       streamInfo.stream.bandwidth = Number(bandwidth);
  2243.     }
  2245.     this.uriToStreamInfosMap_.set(verbatimImagePlaylistUri, streamInfo);
  2246.     return streamInfo;
  2247.   }
  2249.   /**
  2250.    * Parse EXT-X-I-FRAME-STREAM-INF media tag into a Stream object.
  2251.    *
  2252.    * @param {shaka.hls.Tag} tag
  2253.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2254.    * @private
  2255.    */
  2256.   createStreamInfoFromIframeTag_(tag) {
  2257.     goog.asserts.assert(tag.name == 'EXT-X-I-FRAME-STREAM-INF',
  2258.         'Should only be called on iframe tags!');
  2259.     /** @type {string} */
  2260.     const type = shaka.util.ManifestParserUtils.ContentType.IMAGE;
  2262.     const verbatimIFramePlaylistUri = tag.getRequiredAttrValue('URI');
  2263.     const codecs = tag.getAttributeValue('CODECS') || '';
  2265.     // Check if the stream has already been created as part of another Variant
  2266.     // and return it if it has.
  2267.     if (this.uriToStreamInfosMap_.has(verbatimIFramePlaylistUri)) {
  2268.       return this.uriToStreamInfosMap_.get(verbatimIFramePlaylistUri);
  2269.     }
  2271.     const language = tag.getAttributeValue('LANGUAGE');
  2272.     const name = tag.getAttributeValue('NAME');
  2274.     const characteristics = tag.getAttributeValue('CHARACTERISTICS');
  2276.     const streamInfo = this.createStreamInfo_(
  2277.         this.globalId_++, [verbatimIFramePlaylistUri], codecs, type, language,
  2278.         /* primary= */ false, name, /* channelsCount= */ null,
  2279.         /* closedCaptions= */ null, characteristics, /* forced= */ false,
  2280.         /* sampleRate= */ null, /* spatialAudio= */ false);
  2282.     // Parse misc attributes.
  2283.     const resolution = tag.getAttributeValue('RESOLUTION');
  2284.     const [width, height] = resolution ? resolution.split('x') : [null, null];
  2285.     streamInfo.stream.width = Number(width) || undefined;
  2286.     streamInfo.stream.height = Number(height) || undefined;
  2287.     const bandwidth = tag.getAttributeValue('BANDWIDTH');
  2288.     if (bandwidth) {
  2289.       streamInfo.stream.bandwidth = Number(bandwidth);
  2290.     }
  2292.     this.uriToStreamInfosMap_.set(verbatimIFramePlaylistUri, streamInfo);
  2293.     return streamInfo;
  2294.   }
  2296.   /**
  2297.    * Parse an EXT-X-STREAM-INF media tag into a Stream object.
  2298.    *
  2299.    * @param {!Array.<!shaka.hls.Tag>} tags
  2300.    * @param {!Array.<string>} allCodecs
  2301.    * @param {string} type
  2302.    * @param {?string} language
  2303.    * @param {?string} name
  2304.    * @param {?number} channelsCount
  2305.    * @param {?string} characteristics
  2306.    * @param {?number} sampleRate
  2307.    * @param {boolean} spatialAudio
  2308.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2309.    * @private
  2310.    */
  2311.   createStreamInfoFromVariantTags_(tags, allCodecs, type, language, name,
  2312.       channelsCount, characteristics, sampleRate, spatialAudio) {
  2313.     const streamId = this.globalId_++;
  2314.     const verbatimMediaPlaylistUris = [];
  2315.     for (const tag of tags) {
  2316.       goog.asserts.assert(tag.name == 'EXT-X-STREAM-INF',
  2317.           'Should only be called on variant tags!');
  2318.       const uri = tag.getRequiredAttrValue('URI');
  2319.       const pathwayId = tag.getAttributeValue('PATHWAY-ID');
  2320.       if (this.contentSteeringManager_ && pathwayId) {
  2321.         this.contentSteeringManager_.addLocation(streamId, pathwayId, uri);
  2322.       }
  2323.       verbatimMediaPlaylistUris.push(uri);
  2324.     }
  2326.     const key = verbatimMediaPlaylistUris.sort().join(',');
  2327.     if (this.uriToStreamInfosMap_.has(key)) {
  2328.       return this.uriToStreamInfosMap_.get(key);
  2329.     }
  2331.     const closedCaptions = this.getClosedCaptions_(tags[0], type);
  2332.     const codecs = shaka.util.ManifestParserUtils.guessCodecs(type, allCodecs);
  2333.     const streamInfo = this.createStreamInfo_(
  2334.         streamId, verbatimMediaPlaylistUris, codecs, type, language,
  2335.         /* primary= */ false, name, channelsCount, closedCaptions,
  2336.         characteristics, /* forced= */ false, sampleRate,
  2337.         /* spatialAudio= */ false);
  2339.     this.uriToStreamInfosMap_.set(key, streamInfo);
  2340.     return streamInfo;
  2341.   }
  2344.   /**
  2345.    * @param {number} streamId
  2346.    * @param {!Array.<string>} verbatimMediaPlaylistUris
  2347.    * @param {string} codecs
  2348.    * @param {string} type
  2349.    * @param {?string} languageValue
  2350.    * @param {boolean} primary
  2351.    * @param {?string} name
  2352.    * @param {?number} channelsCount
  2353.    * @param {Map.<string, string>} closedCaptions
  2354.    * @param {?string} characteristics
  2355.    * @param {boolean} forced
  2356.    * @param {?number} sampleRate
  2357.    * @param {boolean} spatialAudio
  2358.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2359.    * @private
  2360.    */
  2361.   createStreamInfo_(streamId, verbatimMediaPlaylistUris, codecs, type,
  2362.       languageValue, primary, name, channelsCount, closedCaptions,
  2363.       characteristics, forced, sampleRate, spatialAudio) {
  2364.     // TODO: Refactor, too many parameters
  2366.     // This stream is lazy-loaded inside the createSegmentIndex function.
  2367.     // So we start out with a stream object that does not contain the actual
  2368.     // segment index, then download when createSegmentIndex is called.
  2369.     const stream = this.makeStreamObject_(streamId, codecs, type,
  2370.         languageValue, primary, name, channelsCount, closedCaptions,
  2371.         characteristics, forced, sampleRate, spatialAudio);
  2373.     const redirectUris = [];
  2374.     const getUris = () => {
  2375.       if (this.contentSteeringManager_ &&
  2376.           verbatimMediaPlaylistUris.length > 1) {
  2377.         return this.contentSteeringManager_.getLocations(streamId);
  2378.       }
  2379.       return redirectUris.concat(shaka.hls.Utils.constructUris(
  2380.           [this.masterPlaylistUri_], verbatimMediaPlaylistUris,
  2381.           this.globalVariables_));
  2382.     };
  2383.     const streamInfo = {
  2384.       stream,
  2385.       type,
  2386.       redirectUris,
  2387.       getUris,
  2388.       // These values are filled out or updated after lazy-loading:
  2389.       minTimestamp: 0,
  2390.       maxTimestamp: 0,
  2391.       mediaSequenceToStartTime: new Map(),
  2392.       canSkipSegments: false,
  2393.       canBlockReload: false,
  2394.       hasEndList: false,
  2395.       firstSequenceNumber: -1,
  2396.       nextMediaSequence: -1,
  2397.       nextPart: -1,
  2398.       loadedOnce: false,
  2399.     };
  2401.     /** @param {!AbortSignal} abortSignal */
  2402.     const downloadSegmentIndex = async (abortSignal) => {
  2403.       const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2405.       const uris = streamInfo.getUris();
  2406.       // Download the actual manifest.
  2407.       let response;
  2408.       try {
  2409.         response = await this.requestManifest_(
  2410.             streamInfo.getUris(), /* isPlaylist= */ true);
  2411.       } catch (e) {
  2412.         stream.closeSegmentIndex();
  2413.         const handled = this.playerInterface_.disableStream(stream);
  2414.         if (handled) {
  2415.           return;
  2416.         } else {
  2417.           throw e;
  2418.         }
  2419.       }
  2420.       if (abortSignal.aborted) {
  2421.         return;
  2422.       }
  2424.       // Record the final URI after redirects.
  2425.       const responseUri = response.uri;
  2426.       if (responseUri != response.originalUri && !uris.includes(responseUri)) {
  2427.         redirectUris.push(responseUri);
  2428.       }
  2430.       // Record the redirected, final URI of this media playlist when we parse
  2431.       // it.
  2432.       /** @type {!shaka.hls.Playlist} */
  2433.       const playlist = this.manifestTextParser_.parsePlaylist(response.data);
  2435.       if (playlist.type != shaka.hls.PlaylistType.MEDIA) {
  2436.         throw new shaka.util.Error(
  2437.             shaka.util.Error.Severity.CRITICAL,
  2438.             shaka.util.Error.Category.MANIFEST,
  2439.             shaka.util.Error.Code.HLS_INVALID_PLAYLIST_HIERARCHY);
  2440.       }
  2442.       /** @type {!Array.<!shaka.hls.Tag>} */
  2443.       const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  2444.           'EXT-X-DEFINE');
  2446.       const mediaVariables =
  2447.           this.parseMediaVariables_(variablesTags, responseUri);
  2449.       const mimeType = undefined;
  2451.       let requestBasicInfo = false;
  2453.       // If no codec info was provided in the manifest and codec guessing is
  2454.       // disabled we try to get necessary info from the media data.
  2455.       if ((!this.codecInfoInManifest_ &&
  2456.           this.config_.hls.disableCodecGuessing) ||
  2457.           (this.needsClosedCaptionsDetection_ && type == ContentType.VIDEO &&
  2458.           !this.config_.hls.disableClosedCaptionsDetection)) {
  2459.         if (playlist.segments.length > 0) {
  2460.           this.needsClosedCaptionsDetection_ = false;
  2461.           requestBasicInfo = true;
  2462.         }
  2463.       }
  2465.       const allowOverrideMimeType = !this.codecInfoInManifest_ &&
  2466.         this.config_.hls.disableCodecGuessing;
  2468.       const wasLive = this.isLive_();
  2469.       const realStreamInfo = await this.convertParsedPlaylistIntoStreamInfo_(
  2470.           streamId, mediaVariables, playlist, getUris, responseUri, codecs,
  2471.           type, languageValue, primary, name, channelsCount, closedCaptions,
  2472.           characteristics, forced, sampleRate, spatialAudio, mimeType,
  2473.           requestBasicInfo, allowOverrideMimeType);
  2474.       if (abortSignal.aborted) {
  2475.         return;
  2476.       }
  2478.       const realStream = realStreamInfo.stream;
  2480.       if (this.isLive_() && !wasLive) {
  2481.         // Now that we know that the presentation is live, convert the timeline
  2482.         // to live.
  2483.         this.changePresentationTimelineToLive_(playlist);
  2484.       }
  2486.       // Copy values from the real stream info to our initial one.
  2487.       streamInfo.minTimestamp = realStreamInfo.minTimestamp;
  2488.       streamInfo.maxTimestamp = realStreamInfo.maxTimestamp;
  2489.       streamInfo.canSkipSegments = realStreamInfo.canSkipSegments;
  2490.       streamInfo.canBlockReload = realStreamInfo.canBlockReload;
  2491.       streamInfo.hasEndList = realStreamInfo.hasEndList;
  2492.       streamInfo.mediaSequenceToStartTime =
  2493.           realStreamInfo.mediaSequenceToStartTime;
  2494.       streamInfo.nextMediaSequence = realStreamInfo.nextMediaSequence;
  2495.       streamInfo.nextPart = realStreamInfo.nextPart;
  2496.       streamInfo.loadedOnce = true;
  2497.       stream.segmentIndex = realStream.segmentIndex;
  2498.       stream.encrypted = realStream.encrypted;
  2499.       stream.drmInfos = realStream.drmInfos;
  2500.       stream.keyIds = realStream.keyIds;
  2501.       stream.mimeType = realStream.mimeType;
  2502.       stream.bandwidth = stream.bandwidth || realStream.bandwidth;
  2503.       stream.codecs = stream.codecs || realStream.codecs;
  2504.       stream.closedCaptions =
  2505.           stream.closedCaptions || realStream.closedCaptions;
  2506.       stream.width = stream.width || realStream.width;
  2507.       stream.height = stream.height || realStream.height;
  2508.       stream.hdr = stream.hdr || realStream.hdr;
  2509.       stream.colorGamut = stream.colorGamut || realStream.colorGamut;
  2510.       if (stream.language == 'und' && realStream.language != 'und') {
  2511.         stream.language = realStream.language;
  2512.       }
  2513.       stream.language = stream.language || realStream.language;
  2514.       stream.channelsCount = stream.channelsCount || realStream.channelsCount;
  2515.       stream.audioSamplingRate =
  2516.           stream.audioSamplingRate || realStream.audioSamplingRate;
  2517.       this.setFullTypeForStream_(stream);
  2519.       // Since we lazy-loaded this content, the player may need to create new
  2520.       // sessions for the DRM info in this stream.
  2521.       if (stream.drmInfos.length) {
  2522.         this.playerInterface_.newDrmInfo(stream);
  2523.       }
  2525.       let closedCaptionsUpdated = false;
  2526.       if ((!closedCaptions && stream.closedCaptions) ||
  2527.         (closedCaptions && stream.closedCaptions &&
  2528.         closedCaptions.size != stream.closedCaptions.size)) {
  2529.         closedCaptionsUpdated = true;
  2530.       }
  2532.       if (this.manifest_ && closedCaptionsUpdated) {
  2533.         this.playerInterface_.makeTextStreamsForClosedCaptions(this.manifest_);
  2534.       }
  2536.       if (type == ContentType.VIDEO || type == ContentType.AUDIO) {
  2537.         for (const otherStreamInfo of this.uriToStreamInfosMap_.values()) {
  2538.           if (!otherStreamInfo.loadedOnce && otherStreamInfo.type == type) {
  2539.             // To aid manifest filtering, assume before loading that all video
  2540.             // renditions have the same MIME type.  (And likewise for audio.)
  2541.             otherStreamInfo.stream.mimeType = realStream.mimeType;
  2542.             this.setFullTypeForStream_(otherStreamInfo.stream);
  2543.           }
  2544.         }
  2545.       }
  2547.       if (type == ContentType.TEXT) {
  2548.         const firstSegment = realStream.segmentIndex.get(0);
  2549.         if (firstSegment && firstSegment.initSegmentReference) {
  2550.           stream.mimeType = 'application/mp4';
  2551.           this.setFullTypeForStream_(stream);
  2552.         }
  2553.       }
  2555.       const qualityInfo =
  2556.           shaka.media.QualityObserver.createQualityInfo(stream);
  2557.       stream.segmentIndex.forEachTopLevelReference((reference) => {
  2558.         if (reference.initSegmentReference) {
  2559.           reference.initSegmentReference.mediaQuality = qualityInfo;
  2560.         }
  2561.       });
  2563.       // Add finishing touches to the stream that can only be done once we have
  2564.       // more full context on the media as a whole.
  2565.       if (this.hasEnoughInfoToFinalizeStreams_()) {
  2566.         if (!this.streamsFinalized_) {
  2567.           // Mark this manifest as having been finalized, so we don't go through
  2568.           // this whole process of finishing touches a second time.
  2569.           this.streamsFinalized_ = true;
  2570.           // Finalize all of the currently-loaded streams.
  2571.           const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  2572.           const activeStreamInfos =
  2573.               streamInfos.filter((s) => s.stream.segmentIndex);
  2574.           this.finalizeStreams_(activeStreamInfos);
  2575.           // With the addition of this new stream, we now have enough info to
  2576.           // figure out how long the streams should be. So process all streams
  2577.           // we have downloaded up until this point.
  2578.           this.determineDuration_();
  2579.           // Finally, start the update timer, if this asset has been determined
  2580.           // to be a livestream.
  2581.           const delay = this.getUpdatePlaylistDelay_();
  2582.           if (delay > 0) {
  2583.             this.updatePlaylistTimer_.tickAfter(/* seconds= */ delay);
  2584.           }
  2585.         } else {
  2586.           // We don't need to go through the full process; just finalize this
  2587.           // single stream.
  2588.           this.finalizeStreams_([streamInfo]);
  2589.         }
  2590.       }
  2592.       this.processDateRangeTags_(
  2593.           playlist.tags, stream.type, mediaVariables, getUris);
  2594.     };
  2596.     /** @type {Promise} */
  2597.     let creationPromise = null;
  2598.     /** @type {!AbortController} */
  2599.     let abortController = new AbortController();
  2600.     const safeCreateSegmentIndex = () => {
  2601.       // An operation is already in progress.  The second and subsequent
  2602.       // callers receive the same Promise as the first caller, and only one
  2603.       // download operation will occur.
  2604.       if (creationPromise) {
  2605.         return creationPromise;
  2606.       }
  2608.       // Create a new AbortController to be able to cancel this specific
  2609.       // download.
  2610.       abortController = new AbortController();
  2612.       // Create a Promise tied to the outcome of downloadSegmentIndex().  If
  2613.       // downloadSegmentIndex is rejected, creationPromise will also be
  2614.       // rejected.
  2615.       creationPromise = new Promise((resolve) => {
  2616.         resolve(downloadSegmentIndex(abortController.signal));
  2617.       });
  2618.       return creationPromise;
  2619.     };
  2621.     stream.createSegmentIndex = safeCreateSegmentIndex;
  2623.     stream.closeSegmentIndex = () => {
  2624.       // If we're mid-creation, cancel it.
  2625.       if (creationPromise && !stream.segmentIndex) {
  2626.         abortController.abort();
  2627.       }
  2628.       // If we have a segment index, release it.
  2629.       if (stream.segmentIndex) {
  2630.         stream.segmentIndex.release();
  2631.         stream.segmentIndex = null;
  2632.       }
  2633.       // Clear the creation Promise so that a new operation can begin.
  2634.       creationPromise = null;
  2635.     };
  2637.     return streamInfo;
  2638.   }
  2640.   /**
  2641.    * @return {number}
  2642.    * @private
  2643.    */
  2644.   getMinDuration_() {
  2645.     let minDuration = Infinity;
  2646.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  2647.       if (streamInfo.stream.segmentIndex && streamInfo.stream.type != 'text') {
  2648.         // Since everything is already offset to 0 (either by sync or by being
  2649.         // VOD), only maxTimestamp is necessary to compute the duration.
  2650.         minDuration = Math.min(minDuration, streamInfo.maxTimestamp);
  2651.       }
  2652.     }
  2653.     return minDuration;
  2654.   }
  2656.   /**
  2657.    * @return {number}
  2658.    * @private
  2659.    */
  2660.   getLiveDuration_() {
  2661.     let maxTimestamp = Infinity;
  2662.     let minTimestamp = Infinity;
  2663.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  2664.       if (streamInfo.stream.segmentIndex && streamInfo.stream.type != 'text') {
  2665.         maxTimestamp = Math.min(maxTimestamp, streamInfo.maxTimestamp);
  2666.         minTimestamp = Math.min(minTimestamp, streamInfo.minTimestamp);
  2667.       }
  2668.     }
  2669.     return maxTimestamp - minTimestamp;
  2670.   }
  2672.   /**
  2673.    * @param {!Array.<!shaka.extern.Stream>} streams
  2674.    * @private
  2675.    */
  2676.   notifySegmentsForStreams_(streams) {
  2677.     const references = [];
  2678.     for (const stream of streams) {
  2679.       if (!stream.segmentIndex) {
  2680.         // The stream was closed since the list of streams was built.
  2681.         continue;
  2682.       }
  2683.       stream.segmentIndex.forEachTopLevelReference((reference) => {
  2684.         references.push(reference);
  2685.       });
  2686.     }
  2687.     this.presentationTimeline_.notifySegments(references);
  2688.   }
  2690.   /**
  2691.    * @param {!Array.<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  2692.    * @private
  2693.    */
  2694.   finalizeStreams_(streamInfos) {
  2695.     if (!this.isLive_()) {
  2696.       const minDuration = this.getMinDuration_();
  2697.       for (const streamInfo of streamInfos) {
  2698.         streamInfo.stream.segmentIndex.fit(/* periodStart= */ 0, minDuration);
  2699.       }
  2700.     }
  2701.     this.notifySegmentsForStreams_(streamInfos.map((s) => s.stream));
  2702.     if (this.config_.hls.ignoreManifestProgramDateTime) {
  2703.       this.syncStreamsWithSequenceNumber_(streamInfos);
  2704.     } else {
  2705.       this.syncStreamsWithProgramDateTime_(streamInfos);
  2706.       if (this.config_.hls.ignoreManifestProgramDateTimeForTypes.length > 0) {
  2707.         this.syncStreamsWithSequenceNumber_(streamInfos);
  2708.       }
  2709.     }
  2710.   }
  2712.   /**
  2713.    * @param {string} type
  2714.    * @return {boolean}
  2715.    * @private
  2716.    */
  2717.   ignoreManifestProgramDateTimeFor_(type) {
  2718.     if (this.config_.hls.ignoreManifestProgramDateTime) {
  2719.       return true;
  2720.     }
  2721.     const forTypes = this.config_.hls.ignoreManifestProgramDateTimeForTypes;
  2722.     return forTypes.includes(type);
  2723.   }
  2725.   /**
  2726.    * There are some values on streams that can only be set once we know about
  2727.    * both the video and audio content, if present.
  2728.    * This checks if there is at least one video downloaded (if the media has
  2729.    * video), and that there is at least one audio downloaded (if the media has
  2730.    * audio).
  2731.    * @return {boolean}
  2732.    * @private
  2733.    */
  2734.   hasEnoughInfoToFinalizeStreams_() {
  2735.     if (!this.manifest_) {
  2736.       return false;
  2737.     }
  2738.     const videos = [];
  2739.     const audios = [];
  2740.     for (const variant of this.manifest_.variants) {
  2741.       if (variant.video) {
  2742.         videos.push(variant.video);
  2743.       }
  2744.       if (variant.audio) {
  2745.         audios.push(variant.audio);
  2746.       }
  2747.     }
  2748.     if (videos.length > 0 && !videos.some((stream) => stream.segmentIndex)) {
  2749.       return false;
  2750.     }
  2751.     if (audios.length > 0 && !audios.some((stream) => stream.segmentIndex)) {
  2752.       return false;
  2753.     }
  2754.     return true;
  2755.   }
  2757.   /**
  2758.    * @param {number} streamId
  2759.    * @param {!shaka.hls.Playlist} playlist
  2760.    * @param {function():!Array.<string>} getUris
  2761.    * @param {string} responseUri
  2762.    * @param {string} codecs
  2763.    * @param {string} type
  2764.    * @param {?string} languageValue
  2765.    * @param {boolean} primary
  2766.    * @param {?string} name
  2767.    * @param {?number} channelsCount
  2768.    * @param {Map.<string, string>} closedCaptions
  2769.    * @param {?string} characteristics
  2770.    * @param {boolean} forced
  2771.    * @param {?number} sampleRate
  2772.    * @param {boolean} spatialAudio
  2773.    * @param {(string|undefined)} mimeType
  2774.    * @param {boolean=} requestBasicInfo
  2775.    * @param {boolean=} allowOverrideMimeType
  2776.    * @return {!Promise.<!shaka.hls.HlsParser.StreamInfo>}
  2777.    * @private
  2778.    */
  2779.   async convertParsedPlaylistIntoStreamInfo_(streamId, variables, playlist,
  2780.       getUris, responseUri, codecs, type, languageValue, primary, name,
  2781.       channelsCount, closedCaptions, characteristics, forced, sampleRate,
  2782.       spatialAudio, mimeType = undefined, requestBasicInfo = true,
  2783.       allowOverrideMimeType = true) {
  2784.     goog.asserts.assert(playlist.segments != null,
  2785.         'Media playlist should have segments!');
  2787.     this.determinePresentationType_(playlist);
  2789.     if (this.isLive_()) {
  2790.       this.determineLastTargetDuration_(playlist);
  2791.     }
  2793.     const mediaSequenceToStartTime = this.isLive_() ?
  2794.         this.mediaSequenceToStartTimeByType_.get(type) : new Map();
  2796.     const {segments, bandwidth} = this.createSegments_(
  2797.         playlist, mediaSequenceToStartTime, variables, getUris, type);
  2799.     let width = null;
  2800.     let height = null;
  2801.     let videoRange = null;
  2802.     let colorGamut = null;
  2803.     if (segments.length > 0 && requestBasicInfo) {
  2804.       const basicInfo = await this.getBasicInfoFromSegments_(segments);
  2806.       type = basicInfo.type;
  2807.       languageValue = basicInfo.language;
  2808.       channelsCount = basicInfo.channelCount;
  2809.       sampleRate = basicInfo.sampleRate;
  2810.       if (!this.config_.disableText) {
  2811.         closedCaptions = basicInfo.closedCaptions;
  2812.       }
  2814.       height = basicInfo.height;
  2815.       width = basicInfo.width;
  2816.       videoRange = basicInfo.videoRange;
  2817.       colorGamut = basicInfo.colorGamut;
  2819.       if (allowOverrideMimeType) {
  2820.         mimeType = basicInfo.mimeType;
  2821.         codecs = basicInfo.codecs;
  2822.       }
  2823.     }
  2825.     if (!mimeType) {
  2826.       mimeType = await this.guessMimeType_(type, codecs, segments);
  2827.     }
  2829.     const {drmInfos, keyIds, encrypted, aesEncrypted} =
  2830.         await this.parseDrmInfo_(playlist, mimeType, getUris, variables);
  2832.     if (encrypted && !drmInfos.length && !aesEncrypted) {
  2833.       throw new shaka.util.Error(
  2834.           shaka.util.Error.Severity.CRITICAL,
  2835.           shaka.util.Error.Category.MANIFEST,
  2836.           shaka.util.Error.Code.HLS_KEYFORMATS_NOT_SUPPORTED);
  2837.     }
  2839.     const stream = this.makeStreamObject_(streamId, codecs, type,
  2840.         languageValue, primary, name, channelsCount, closedCaptions,
  2841.         characteristics, forced, sampleRate, spatialAudio);
  2842.     stream.encrypted = encrypted;
  2843.     stream.drmInfos = drmInfos;
  2844.     stream.keyIds = keyIds;
  2845.     stream.mimeType = mimeType;
  2846.     if (bandwidth) {
  2847.       stream.bandwidth = bandwidth;
  2848.     }
  2849.     this.setFullTypeForStream_(stream);
  2851.     if (type == shaka.util.ManifestParserUtils.ContentType.VIDEO &&
  2852.         (width || height || videoRange || colorGamut)) {
  2853.       this.addVideoAttributes_(stream, width, height,
  2854.           /* frameRate= */ null, videoRange, /* videoLayout= */ null,
  2855.           colorGamut);
  2856.     }
  2858.     // This new calculation is necessary for Low Latency streams.
  2859.     if (this.isLive_()) {
  2860.       this.determineLastTargetDuration_(playlist);
  2861.     }
  2863.     const firstStartTime = segments[0].startTime;
  2864.     const lastSegment = segments[segments.length - 1];
  2865.     const lastEndTime = lastSegment.endTime;
  2866.     /** @type {!shaka.media.SegmentIndex} */
  2867.     const segmentIndex = new shaka.media.SegmentIndex(segments);
  2868.     stream.segmentIndex = segmentIndex;
  2870.     const serverControlTag = shaka.hls.Utils.getFirstTagWithName(
  2871.         playlist.tags, 'EXT-X-SERVER-CONTROL');
  2872.     const canSkipSegments = serverControlTag ?
  2873.           serverControlTag.getAttribute('CAN-SKIP-UNTIL') != null : false;
  2874.     const canBlockReload = serverControlTag ?
  2875.           serverControlTag.getAttribute('CAN-BLOCK-RELOAD') != null : false;
  2877.     const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  2878.         playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  2880.     const {nextMediaSequence, nextPart} =
  2881.         this.getNextMediaSequenceAndPart_(mediaSequenceNumber, segments);
  2883.     return {
  2884.       stream,
  2885.       type,
  2886.       redirectUris: [],
  2887.       getUris,
  2888.       minTimestamp: firstStartTime,
  2889.       maxTimestamp: lastEndTime,
  2890.       canSkipSegments,
  2891.       canBlockReload,
  2892.       hasEndList: false,
  2893.       firstSequenceNumber: -1,
  2894.       nextMediaSequence,
  2895.       nextPart,
  2896.       mediaSequenceToStartTime,
  2897.       loadedOnce: false,
  2898.     };
  2899.   }
  2901.   /**
  2902.    * Get the next msn and part
  2903.    *
  2904.    * @param {number} mediaSequenceNumber
  2905.    * @param {!Array.<!shaka.media.SegmentReference>} segments
  2906.    * @return {{nextMediaSequence: number, nextPart:number}}}
  2907.    * @private
  2908.    */
  2909.   getNextMediaSequenceAndPart_(mediaSequenceNumber, segments) {
  2910.     const currentMediaSequence = mediaSequenceNumber + segments.length - 1;
  2911.     let nextMediaSequence = currentMediaSequence;
  2912.     let nextPart = -1;
  2913.     if (!segments.length) {
  2914.       nextMediaSequence++;
  2915.       return {
  2916.         nextMediaSequence,
  2917.         nextPart,
  2918.       };
  2919.     }
  2920.     const lastSegment = segments[segments.length - 1];
  2921.     const partialReferences = lastSegment.partialReferences;
  2922.     if (!lastSegment.partialReferences.length) {
  2923.       nextMediaSequence++;
  2924.       if (lastSegment.hasByterangeOptimization()) {
  2925.         nextPart = 0;
  2926.       }
  2927.       return {
  2928.         nextMediaSequence,
  2929.         nextPart,
  2930.       };
  2931.     }
  2932.     nextPart = partialReferences.length - 1;
  2933.     const lastPartialReference =
  2934.         partialReferences[partialReferences.length - 1];
  2935.     if (!lastPartialReference.isPreload()) {
  2936.       nextMediaSequence++;
  2937.       nextPart = 0;
  2938.     }
  2939.     return {
  2940.       nextMediaSequence,
  2941.       nextPart,
  2942.     };
  2943.   }
  2946.   /**
  2947.    * Creates a stream object with the given parameters.
  2948.    * The parameters that are passed into here are only the things that can be
  2949.    * known without downloading the media playlist; other values must be set
  2950.    * manually on the object after creation.
  2951.    * @param {number} id
  2952.    * @param {string} codecs
  2953.    * @param {string} type
  2954.    * @param {?string} languageValue
  2955.    * @param {boolean} primary
  2956.    * @param {?string} name
  2957.    * @param {?number} channelsCount
  2958.    * @param {Map.<string, string>} closedCaptions
  2959.    * @param {?string} characteristics
  2960.    * @param {boolean} forced
  2961.    * @param {?number} sampleRate
  2962.    * @param {boolean} spatialAudio
  2963.    * @return {!shaka.extern.Stream}
  2964.    * @private
  2965.    */
  2966.   makeStreamObject_(id, codecs, type, languageValue, primary, name,
  2967.       channelsCount, closedCaptions, characteristics, forced, sampleRate,
  2968.       spatialAudio) {
  2969.     // Fill out a "best-guess" mimeType, for now. It will be replaced once the
  2970.     // stream is lazy-loaded.
  2971.     const mimeType = this.guessMimeTypeBeforeLoading_(type, codecs) ||
  2972.         this.guessMimeTypeFallback_(type);
  2973.     const roles = [];
  2974.     if (characteristics) {
  2975.       for (const characteristic of characteristics.split(',')) {
  2976.         roles.push(characteristic);
  2977.       }
  2978.     }
  2980.     let kind = undefined;
  2981.     let accessibilityPurpose = null;
  2982.     if (type == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2983.       if (roles.includes('public.accessibility.transcribes-spoken-dialog') &&
  2984.           roles.includes('public.accessibility.describes-music-and-sound')) {
  2985.         kind = shaka.util.ManifestParserUtils.TextStreamKind.CLOSED_CAPTION;
  2986.       } else {
  2987.         kind = shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE;
  2988.       }
  2989.     } else {
  2990.       if (roles.includes('public.accessibility.describes-video')) {
  2991.         accessibilityPurpose =
  2992.               shaka.media.ManifestParser.AccessibilityPurpose.VISUALLY_IMPAIRED;
  2993.       }
  2994.     }
  2996.     // If there are no roles, and we have defaulted to the subtitle "kind" for
  2997.     // this track, add the implied subtitle role.
  2998.     if (!roles.length &&
  2999.         kind === shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE) {
  3000.       roles.push(shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE);
  3001.     }
  3003.     const stream = {
  3004.       id: this.globalId_++,
  3005.       originalId: name,
  3006.       groupId: null,
  3007.       createSegmentIndex: () => Promise.resolve(),
  3008.       segmentIndex: null,
  3009.       mimeType,
  3010.       codecs,
  3011.       kind: (type == shaka.util.ManifestParserUtils.ContentType.TEXT) ?
  3012.           shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE : undefined,
  3013.       encrypted: false,
  3014.       drmInfos: [],
  3015.       keyIds: new Set(),
  3016.       language: this.getLanguage_(languageValue),
  3017.       originalLanguage: languageValue,
  3018.       label: name,  // For historical reasons, since before "originalId".
  3019.       type,
  3020.       primary,
  3021.       // TODO: trick mode
  3022.       trickModeVideo: null,
  3023.       emsgSchemeIdUris: null,
  3024.       frameRate: undefined,
  3025.       pixelAspectRatio: undefined,
  3026.       width: undefined,
  3027.       height: undefined,
  3028.       bandwidth: undefined,
  3029.       roles,
  3030.       forced,
  3031.       channelsCount,
  3032.       audioSamplingRate: sampleRate,
  3033.       spatialAudio,
  3034.       closedCaptions,
  3035.       hdr: undefined,
  3036.       colorGamut: undefined,
  3037.       videoLayout: undefined,
  3038.       tilesLayout: undefined,
  3039.       accessibilityPurpose: accessibilityPurpose,
  3040.       external: false,
  3041.       fastSwitching: false,
  3042.       fullMimeTypes: new Set(),
  3043.     };
  3044.     this.setFullTypeForStream_(stream);
  3045.     return stream;
  3046.   }
  3048.   /**
  3049.    * @param {!shaka.hls.Playlist} playlist
  3050.    * @param {string} mimeType
  3051.    * @param {function():!Array.<string>} getUris
  3052.    * @param {?Map.<string, string>=} variables
  3053.    * @return {Promise.<{
  3054.    *   drmInfos: !Array.<shaka.extern.DrmInfo>,
  3055.    *   keyIds: !Set.<string>,
  3056.    *   encrypted: boolean,
  3057.    *   aesEncrypted: boolean
  3058.    * }>}
  3059.    * @private
  3060.    */
  3061.   async parseDrmInfo_(playlist, mimeType, getUris, variables) {
  3062.     /** @type {!Map<!shaka.hls.Tag, ?shaka.media.InitSegmentReference>} */
  3063.     const drmTagsMap = new Map();
  3064.     if (playlist.segments) {
  3065.       for (const segment of playlist.segments) {
  3066.         const segmentKeyTags = shaka.hls.Utils.filterTagsByName(segment.tags,
  3067.             'EXT-X-KEY');
  3068.         let initSegmentRef = null;
  3069.         if (segmentKeyTags.length) {
  3070.           initSegmentRef = this.getInitSegmentReference_(playlist,
  3071.               segment.tags, getUris, variables);
  3072.           for (const segmentKeyTag of segmentKeyTags) {
  3073.             drmTagsMap.set(segmentKeyTag, initSegmentRef);
  3074.           }
  3075.         }
  3076.       }
  3077.     }
  3079.     let encrypted = false;
  3080.     let aesEncrypted = false;
  3082.     /** @type {!Array.<shaka.extern.DrmInfo>}*/
  3083.     const drmInfos = [];
  3084.     const keyIds = new Set();
  3086.     for (const [key, value] of drmTagsMap) {
  3087.       const drmTag = /** @type {!shaka.hls.Tag} */ (key);
  3088.       const initSegmentRef =
  3089.       /** @type {?shaka.media.InitSegmentReference} */ (value);
  3090.       const method = drmTag.getRequiredAttrValue('METHOD');
  3091.       if (method != 'NONE') {
  3092.         encrypted = true;
  3094.         // According to the HLS spec, KEYFORMAT is optional and implicitly
  3095.         // defaults to "identity".
  3096.         // https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-4.4.4.4
  3097.         const keyFormat =
  3098.             drmTag.getAttributeValue('KEYFORMAT') || 'identity';
  3099.         let drmInfo = null;
  3101.         if (this.isAesMethod_(method)) {
  3102.           // These keys are handled separately.
  3103.           aesEncrypted = true;
  3104.           continue;
  3105.         } else if (keyFormat == 'identity') {
  3106.           // eslint-disable-next-line no-await-in-loop
  3107.           drmInfo = await this.identityDrmParser_(
  3108.               drmTag, mimeType, getUris, initSegmentRef, variables);
  3109.         } else {
  3110.           const drmParser =
  3111.               shaka.hls.HlsParser.KEYFORMATS_TO_DRM_PARSERS_[keyFormat];
  3112.           drmInfo = drmParser ? drmParser(drmTag, mimeType) : null;
  3113.         }
  3114.         if (drmInfo) {
  3115.           if (drmInfo.keyIds) {
  3116.             for (const keyId of drmInfo.keyIds) {
  3117.               keyIds.add(keyId);
  3118.             }
  3119.           }
  3120.           drmInfos.push(drmInfo);
  3121.         } else {
  3122.           shaka.log.warning('Unsupported HLS KEYFORMAT', keyFormat);
  3123.         }
  3124.       }
  3125.     }
  3127.     return {drmInfos, keyIds, encrypted, aesEncrypted};
  3128.   }
  3130.   /**
  3131.    * @param {!shaka.hls.Tag} drmTag
  3132.    * @param {!shaka.hls.Playlist} playlist
  3133.    * @param {function():!Array.<string>} getUris
  3134.    * @param {?Map.<string, string>=} variables
  3135.    * @return {!shaka.extern.aesKey}
  3136.    * @private
  3137.    */
  3138.   parseAESDrmTag_(drmTag, playlist, getUris, variables) {
  3139.     // Check if the Web Crypto API is available.
  3140.     if (!window.crypto || !window.crypto.subtle) {
  3141.       shaka.log.alwaysWarn('Web Crypto API is not available to decrypt ' +
  3142.           'AES. (Web Crypto only exists in secure origins like https)');
  3143.       throw new shaka.util.Error(
  3144.           shaka.util.Error.Severity.CRITICAL,
  3145.           shaka.util.Error.Category.MANIFEST,
  3146.           shaka.util.Error.Code.NO_WEB_CRYPTO_API);
  3147.     }
  3149.     // HLS RFC 8216 Section 5.2:
  3150.     // An EXT-X-KEY tag with a KEYFORMAT of "identity" that does not have an IV
  3151.     // attribute indicates that the Media Sequence Number is to be used as the
  3152.     // IV when decrypting a Media Segment, by putting its big-endian binary
  3153.     // representation into a 16-octet (128-bit) buffer and padding (on the left)
  3154.     // with zeros.
  3155.     let firstMediaSequenceNumber = 0;
  3156.     let iv;
  3157.     const ivHex = drmTag.getAttributeValue('IV', '');
  3158.     if (!ivHex) {
  3159.       // Media Sequence Number will be used as IV.
  3160.       firstMediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  3161.           playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  3162.     } else {
  3163.       // Exclude 0x at the start of string.
  3164.       iv = shaka.util.Uint8ArrayUtils.fromHex(ivHex.substr(2));
  3165.       if (iv.byteLength != 16) {
  3166.         throw new shaka.util.Error(
  3167.             shaka.util.Error.Severity.CRITICAL,
  3168.             shaka.util.Error.Category.MANIFEST,
  3169.             shaka.util.Error.Code.AES_128_INVALID_IV_LENGTH);
  3170.       }
  3171.     }
  3173.     const aesKeyInfoKey = `${drmTag.toString()}-${firstMediaSequenceNumber}`;
  3174.     if (!this.aesKeyInfoMap_.has(aesKeyInfoKey)) {
  3175.       // Default AES-128
  3176.       const keyInfo = {
  3177.         bitsKey: 128,
  3178.         blockCipherMode: 'CBC',
  3179.         iv,
  3180.         firstMediaSequenceNumber,
  3181.       };
  3183.       const method = drmTag.getRequiredAttrValue('METHOD');
  3184.       switch (method) {
  3185.         case 'AES-256':
  3186.           keyInfo.bitsKey = 256;
  3187.           break;
  3188.         case 'AES-256-CTR':
  3189.           keyInfo.bitsKey = 256;
  3190.           keyInfo.blockCipherMode = 'CTR';
  3191.           break;
  3192.       }
  3194.       // Don't download the key object until the segment is parsed, to avoid a
  3195.       // startup delay for long manifests with lots of keys.
  3196.       keyInfo.fetchKey = async () => {
  3197.         const keyUris = shaka.hls.Utils.constructSegmentUris(
  3198.             getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  3200.         const keyMapKey = keyUris.sort().join('');
  3201.         if (!this.aesKeyMap_.has(keyMapKey)) {
  3202.           const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  3203.           const request = shaka.net.NetworkingEngine.makeRequest(
  3204.               keyUris, this.config_.retryParameters);
  3205.           const keyResponse = this.makeNetworkRequest_(request, requestType);
  3206.           this.aesKeyMap_.set(keyMapKey, keyResponse);
  3207.         }
  3208.         const keyResponse = await this.aesKeyMap_.get(keyMapKey);
  3210.         // keyResponse.status is undefined when URI is "data:text/plain;base64,"
  3211.         if (!keyResponse.data ||
  3212.             keyResponse.data.byteLength != (keyInfo.bitsKey / 8)) {
  3213.           throw new shaka.util.Error(
  3214.               shaka.util.Error.Severity.CRITICAL,
  3215.               shaka.util.Error.Category.MANIFEST,
  3216.               shaka.util.Error.Code.AES_128_INVALID_KEY_LENGTH);
  3217.         }
  3219.         const algorithm = {
  3220.           name: keyInfo.blockCipherMode == 'CTR' ? 'AES-CTR' : 'AES-CBC',
  3221.           length: keyInfo.bitsKey,
  3222.         };
  3223.         keyInfo.cryptoKey = await window.crypto.subtle.importKey(
  3224.             'raw', keyResponse.data, algorithm, true, ['decrypt']);
  3225.         keyInfo.fetchKey = undefined; // No longer needed.
  3226.       };
  3227.       this.aesKeyInfoMap_.set(aesKeyInfoKey, keyInfo);
  3228.     }
  3229.     return this.aesKeyInfoMap_.get(aesKeyInfoKey);
  3230.   }
  3233.   /**
  3234.    * @param {!shaka.hls.Playlist} playlist
  3235.    * @private
  3236.    */
  3237.   determinePresentationType_(playlist) {
  3238.     const PresentationType = shaka.hls.HlsParser.PresentationType_;
  3239.     const presentationTypeTag =
  3240.         shaka.hls.Utils.getFirstTagWithName(playlist.tags,
  3241.             'EXT-X-PLAYLIST-TYPE');
  3242.     const endListTag =
  3243.         shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-ENDLIST');
  3245.     const isVod = (presentationTypeTag && presentationTypeTag.value == 'VOD') ||
  3246.         endListTag;
  3247.     const isEvent = presentationTypeTag &&
  3248.         presentationTypeTag.value == 'EVENT' && !isVod;
  3249.     const isLive = !isVod && !isEvent;
  3251.     if (isVod) {
  3252.       this.setPresentationType_(PresentationType.VOD);
  3253.     } else {
  3254.       // If it's not VOD, it must be presentation type LIVE or an ongoing EVENT.
  3255.       if (isLive) {
  3256.         this.setPresentationType_(PresentationType.LIVE);
  3257.       } else {
  3258.         this.setPresentationType_(PresentationType.EVENT);
  3259.       }
  3260.     }
  3261.   }
  3264.   /**
  3265.    * @param {!shaka.hls.Playlist} playlist
  3266.    * @private
  3267.    */
  3268.   determineLastTargetDuration_(playlist) {
  3269.     let lastTargetDuration = Infinity;
  3270.     const segments = playlist.segments;
  3271.     if (segments.length) {
  3272.       let segmentIndex = segments.length - 1;
  3273.       while (segmentIndex >= 0) {
  3274.         const segment = segments[segmentIndex];
  3275.         const extinfTag =
  3276.             shaka.hls.Utils.getFirstTagWithName(segment.tags, 'EXTINF');
  3277.         if (extinfTag) {
  3278.           // The EXTINF tag format is '#EXTINF:<duration>,[<title>]'.
  3279.           // We're interested in the duration part.
  3280.           const extinfValues = extinfTag.value.split(',');
  3281.           lastTargetDuration = Number(extinfValues[0]);
  3282.           break;
  3283.         }
  3284.         segmentIndex--;
  3285.       }
  3286.     }
  3288.     const targetDurationTag = this.getRequiredTag_(playlist.tags,
  3289.         'EXT-X-TARGETDURATION');
  3290.     const targetDuration = Number(targetDurationTag.value);
  3291.     const partialTargetDurationTag =
  3292.       shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-PART-INF');
  3293.     if (partialTargetDurationTag) {
  3294.       this.partialTargetDuration_ = Number(
  3295.           partialTargetDurationTag.getRequiredAttrValue('PART-TARGET'));
  3296.     }
  3297.     // Get the server-recommended min distance from the live edge.
  3298.     const serverControlTag = shaka.hls.Utils.getFirstTagWithName(
  3299.         playlist.tags, 'EXT-X-SERVER-CONTROL');
  3300.     // According to the HLS spec, updates should not happen more often than
  3301.     // once in targetDuration.  It also requires us to only update the active
  3302.     // variant.  We might implement that later, but for now every variant
  3303.     // will be updated.  To get the update period, choose the smallest
  3304.     // targetDuration value across all playlists.
  3305.     // 1. Update the shortest one to use as update period and segment
  3306.     // availability time (for LIVE).
  3307.     if (this.lowLatencyMode_ && this.partialTargetDuration_) {
  3308.       // For low latency streaming, use the partial segment target duration.
  3309.       if (this.lowLatencyByterangeOptimization_) {
  3310.         // We always have at least 1 partial segment part, and most servers
  3311.         // allow you to make a request with _HLS_msn=X&_HLS_part=0 with a
  3312.         // distance of 4 partial segments.  With this we ensure that we
  3313.         // obtain the minimum latency in this type of case.
  3314.         if (this.partialTargetDuration_ * 5 <= lastTargetDuration) {
  3315.           this.lastTargetDuration_ = Math.min(
  3316.               this.partialTargetDuration_, this.lastTargetDuration_);
  3317.         } else {
  3318.           this.lastTargetDuration_ = Math.min(
  3319.               lastTargetDuration, this.lastTargetDuration_);
  3320.         }
  3321.       } else {
  3322.         this.lastTargetDuration_ = Math.min(
  3323.             this.partialTargetDuration_, this.lastTargetDuration_);
  3324.       }
  3325.       // Use 'PART-HOLD-BACK' as the presentation delay for low latency mode.
  3326.       this.lowLatencyPresentationDelay_ = serverControlTag ? Number(
  3327.           serverControlTag.getRequiredAttrValue('PART-HOLD-BACK')) : 0;
  3328.     } else {
  3329.       this.lastTargetDuration_ = Math.min(
  3330.           lastTargetDuration, this.lastTargetDuration_);
  3331.       // Use 'HOLD-BACK' as the presentation delay for default if defined.
  3332.       const holdBack = serverControlTag ?
  3333.           serverControlTag.getAttribute('HOLD-BACK') : null;
  3334.       this.presentationDelay_ = holdBack ? Number(holdBack.value) : 0;
  3335.     }
  3336.     // 2. Update the longest target duration if need be to use as a
  3337.     // presentation delay later.
  3338.     this.maxTargetDuration_ = Math.max(
  3339.         targetDuration, this.maxTargetDuration_);
  3340.   }
  3343.   /**
  3344.    * @param {!shaka.hls.Playlist} playlist
  3345.    * @private
  3346.    */
  3347.   changePresentationTimelineToLive_(playlist) {
  3348.     // The live edge will be calculated from segments, so we don't need to
  3349.     // set a presentation start time.  We will assert later that this is
  3350.     // working as expected.
  3352.     // The HLS spec (RFC 8216) states in 6.3.3:
  3353.     //
  3354.     // "The client SHALL choose which Media Segment to play first ... the
  3355.     // client SHOULD NOT choose a segment that starts less than three target
  3356.     // durations from the end of the Playlist file.  Doing so can trigger
  3357.     // playback stalls."
  3358.     //
  3359.     // We accomplish this in our DASH-y model by setting a presentation
  3360.     // delay of configured value, or 3 segments duration if not configured.
  3361.     // This will be the "live edge" of the presentation.
  3362.     let presentationDelay;
  3363.     if (this.config_.defaultPresentationDelay) {
  3364.       presentationDelay = this.config_.defaultPresentationDelay;
  3365.     } else if (this.lowLatencyPresentationDelay_) {
  3366.       presentationDelay = this.lowLatencyPresentationDelay_;
  3367.     } else if (this.presentationDelay_) {
  3368.       presentationDelay = this.presentationDelay_;
  3369.     } else {
  3370.       const playlistSegments = playlist.segments.length;
  3371.       let delaySegments = this.config_.hls.liveSegmentsDelay;
  3372.       if (delaySegments > (playlistSegments - 2)) {
  3373.         delaySegments = Math.max(1, playlistSegments - 2);
  3374.       }
  3375.       presentationDelay = this.maxTargetDuration_ * delaySegments;
  3376.     }
  3378.     this.presentationTimeline_.setPresentationStartTime(0);
  3379.     this.presentationTimeline_.setDelay(presentationDelay);
  3380.     this.presentationTimeline_.setStatic(false);
  3381.   }
  3383.   /**
  3384.    * Get the InitSegmentReference for a segment if it has a EXT-X-MAP tag.
  3385.    * @param {!shaka.hls.Playlist} playlist
  3386.    * @param {!Array.<!shaka.hls.Tag>} tags Segment tags
  3387.    * @param {function():!Array.<string>} getUris
  3388.    * @param {?Map.<string, string>=} variables
  3389.    * @return {shaka.media.InitSegmentReference}
  3390.    * @private
  3391.    */
  3392.   getInitSegmentReference_(playlist, tags, getUris, variables) {
  3393.     /** @type {?shaka.hls.Tag} */
  3394.     const mapTag = shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-MAP');
  3396.     if (!mapTag) {
  3397.       return null;
  3398.     }
  3399.     // Map tag example: #EXT-X-MAP:URI="main.mp4",BYTERANGE="720@0"
  3400.     const verbatimInitSegmentUri = mapTag.getRequiredAttrValue('URI');
  3401.     const absoluteInitSegmentUris = shaka.hls.Utils.constructSegmentUris(
  3402.         getUris(), verbatimInitSegmentUri, variables);
  3404.     const mapTagKey = [
  3405.       absoluteInitSegmentUris.toString(),
  3406.       mapTag.getAttributeValue('BYTERANGE', ''),
  3407.     ].join('-');
  3408.     if (!this.mapTagToInitSegmentRefMap_.has(mapTagKey)) {
  3409.       /** @type {shaka.extern.aesKey|undefined} */
  3410.       let aesKey = undefined;
  3411.       let byteRangeTag = null;
  3412.       for (const tag of tags) {
  3413.         if (tag.name == 'EXT-X-KEY') {
  3414.           if (this.isAesMethod_(tag.getRequiredAttrValue('METHOD')) &&
  3415.               tag.id < mapTag.id) {
  3416.             aesKey =
  3417.                 this.parseAESDrmTag_(tag, playlist, getUris, variables);
  3418.           }
  3419.         } else if (tag.name == 'EXT-X-BYTERANGE' && tag.id < mapTag.id) {
  3420.           byteRangeTag = tag;
  3421.         }
  3422.       }
  3423.       const initSegmentRef = this.createInitSegmentReference_(
  3424.           absoluteInitSegmentUris, mapTag, byteRangeTag, aesKey);
  3425.       this.mapTagToInitSegmentRefMap_.set(mapTagKey, initSegmentRef);
  3426.     }
  3427.     return this.mapTagToInitSegmentRefMap_.get(mapTagKey);
  3428.   }
  3430.   /**
  3431.    * Create an InitSegmentReference object for the EXT-X-MAP tag in the media
  3432.    * playlist.
  3433.    * @param {!Array.<string>} absoluteInitSegmentUris
  3434.    * @param {!shaka.hls.Tag} mapTag EXT-X-MAP
  3435.    * @param {shaka.hls.Tag=} byteRangeTag EXT-X-BYTERANGE
  3436.    * @param {shaka.extern.aesKey=} aesKey
  3437.    * @return {!shaka.media.InitSegmentReference}
  3438.    * @private
  3439.    */
  3440.   createInitSegmentReference_(absoluteInitSegmentUris, mapTag, byteRangeTag,
  3441.       aesKey) {
  3442.     let startByte = 0;
  3443.     let endByte = null;
  3444.     let byterange = mapTag.getAttributeValue('BYTERANGE');
  3445.     if (!byterange && byteRangeTag) {
  3446.       byterange = byteRangeTag.value;
  3447.     }
  3448.     // If a BYTERANGE attribute is not specified, the segment consists
  3449.     // of the entire resource.
  3450.     if (byterange) {
  3451.       const blocks = byterange.split('@');
  3452.       const byteLength = Number(blocks[0]);
  3453.       startByte = Number(blocks[1]);
  3454.       endByte = startByte + byteLength - 1;
  3456.       if (aesKey) {
  3457.         // MAP segment encrypted with method AES, when served with
  3458.         // HTTP Range, has the unencrypted size specified in the range.
  3459.         // See: https://tools.ietf.org/html/draft-pantos-hls-rfc8216bis-08#section-6.3.6
  3460.         const length = (endByte + 1) - startByte;
  3461.         if (length % 16) {
  3462.           endByte += (16 - (length % 16));
  3463.         }
  3464.       }
  3465.     }
  3467.     const initSegmentRef = new shaka.media.InitSegmentReference(
  3468.         () => absoluteInitSegmentUris,
  3469.         startByte,
  3470.         endByte,
  3471.         /* mediaQuality= */ null,
  3472.         /* timescale= */ null,
  3473.         /* segmentData= */ null,
  3474.         aesKey);
  3475.     return initSegmentRef;
  3476.   }
  3478.   /**
  3479.    * Parses one shaka.hls.Segment object into a shaka.media.SegmentReference.
  3480.    *
  3481.    * @param {shaka.media.InitSegmentReference} initSegmentReference
  3482.    * @param {shaka.media.SegmentReference} previousReference
  3483.    * @param {!shaka.hls.Segment} hlsSegment
  3484.    * @param {number} startTime
  3485.    * @param {!Map.<string, string>} variables
  3486.    * @param {!shaka.hls.Playlist} playlist
  3487.    * @param {string} type
  3488.    * @param {function():!Array.<string>} getUris
  3489.    * @param {shaka.extern.aesKey=} aesKey
  3490.    * @return {shaka.media.SegmentReference}
  3491.    * @private
  3492.    */
  3493.   createSegmentReference_(
  3494.       initSegmentReference, previousReference, hlsSegment, startTime,
  3495.       variables, playlist, type, getUris, aesKey) {
  3496.     const HlsParser = shaka.hls.HlsParser;
  3498.     const getMimeType = (uri) => {
  3499.       const parsedUri = new goog.Uri(uri);
  3500.       const extension = parsedUri.getPath().split('.').pop();
  3501.       const map = HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_[type];
  3502.       let mimeType = map[extension];
  3503.       if (!mimeType) {
  3504.         mimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_[extension];
  3505.       }
  3506.       return mimeType;
  3507.     };
  3509.     const tags = hlsSegment.tags;
  3510.     const extinfTag =
  3511.         shaka.hls.Utils.getFirstTagWithName(tags, 'EXTINF');
  3513.     let endTime = 0;
  3514.     let startByte = 0;
  3515.     let endByte = null;
  3517.     if (hlsSegment.partialSegments.length) {
  3518.       this.manifest_.isLowLatency = true;
  3519.     }
  3521.     let syncTime = null;
  3522.     if (!this.config_.hls.ignoreManifestProgramDateTime) {
  3523.       const dateTimeTag =
  3524.           shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-PROGRAM-DATE-TIME');
  3525.       if (dateTimeTag && dateTimeTag.value) {
  3526.         syncTime = shaka.util.TXml.parseDate(dateTimeTag.value);
  3527.         goog.asserts.assert(syncTime != null,
  3528.             'EXT-X-PROGRAM-DATE-TIME format not valid');
  3529.       }
  3530.     }
  3532.     let status = shaka.media.SegmentReference.Status.AVAILABLE;
  3533.     if (shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-GAP')) {
  3534.       this.manifest_.gapCount++;
  3535.       status = shaka.media.SegmentReference.Status.MISSING;
  3536.     }
  3538.     if (!extinfTag) {
  3539.       if (hlsSegment.partialSegments.length == 0) {
  3540.         // EXTINF tag must be available if the segment has no partial segments.
  3541.         throw new shaka.util.Error(
  3542.             shaka.util.Error.Severity.CRITICAL,
  3543.             shaka.util.Error.Category.MANIFEST,
  3544.             shaka.util.Error.Code.HLS_REQUIRED_TAG_MISSING, 'EXTINF');
  3545.       } else if (!this.lowLatencyMode_) {
  3546.         // Without EXTINF and without low-latency mode, partial segments get
  3547.         // ignored.
  3548.         return null;
  3549.       }
  3550.     }
  3552.     // Create SegmentReferences for the partial segments.
  3553.     let partialSegmentRefs = [];
  3555.     // Optimization for LL-HLS with byterange
  3556.     // More info in https://tinyurl.com/hls-open-byte-range
  3557.     let segmentWithByteRangeOptimization = false;
  3558.     let getUrisOptimization = null;
  3559.     let somePartialSegmentWithGap = false;
  3560.     let isPreloadSegment = false;
  3562.     if (this.lowLatencyMode_ && hlsSegment.partialSegments.length) {
  3563.       const byterangeOptimizationSupport =
  3564.           initSegmentReference && window.ReadableStream &&
  3565.           this.config_.hls.allowLowLatencyByteRangeOptimization;
  3567.       let partialSyncTime = syncTime;
  3568.       for (let i = 0; i < hlsSegment.partialSegments.length; i++) {
  3569.         const item = hlsSegment.partialSegments[i];
  3570.         const pPreviousReference = i == 0 ?
  3571.           previousReference : partialSegmentRefs[partialSegmentRefs.length - 1];
  3572.         const pStartTime = (i == 0) ? startTime : pPreviousReference.endTime;
  3574.         // If DURATION is missing from this partial segment, use the target
  3575.         // partial duration from the top of the playlist, which is a required
  3576.         // attribute for content with partial segments.
  3577.         const pDuration = Number(item.getAttributeValue('DURATION')) ||
  3578.             this.partialTargetDuration_;
  3580.         // If for some reason we have neither an explicit duration, nor a target
  3581.         // partial duration, we should SKIP this partial segment to avoid
  3582.         // duplicating content in the presentation timeline.
  3583.         if (!pDuration) {
  3584.           continue;
  3585.         }
  3587.         const pEndTime = pStartTime + pDuration;
  3589.         let pStartByte = 0;
  3590.         let pEndByte = null;
  3591.         if (item.name == 'EXT-X-PRELOAD-HINT') {
  3592.           // A preload hinted partial segment may have byterange start info.
  3593.           const pByterangeStart = item.getAttributeValue('BYTERANGE-START');
  3594.           pStartByte = pByterangeStart ? Number(pByterangeStart) : 0;
  3595.           // A preload hinted partial segment may have byterange length info.
  3596.           const pByterangeLength = item.getAttributeValue('BYTERANGE-LENGTH');
  3597.           if (pByterangeLength) {
  3598.             pEndByte = pStartByte + Number(pByterangeLength) - 1;
  3599.           } else if (pStartByte) {
  3600.             // If we have a non-zero start byte, but no end byte, follow the
  3601.             // recommendation of https://tinyurl.com/hls-open-byte-range and
  3602.             // set the end byte explicitly to a large integer.
  3603.             pEndByte = Number.MAX_SAFE_INTEGER;
  3604.           }
  3605.         } else {
  3606.           const pByterange = item.getAttributeValue('BYTERANGE');
  3607.           [pStartByte, pEndByte] =
  3608.             this.parseByteRange_(pPreviousReference, pByterange);
  3609.         }
  3610.         const pUri = item.getAttributeValue('URI');
  3611.         if (!pUri) {
  3612.           continue;
  3613.         }
  3615.         let partialStatus = shaka.media.SegmentReference.Status.AVAILABLE;
  3616.         if (item.getAttributeValue('GAP') == 'YES') {
  3617.           this.manifest_.gapCount++;
  3618.           partialStatus = shaka.media.SegmentReference.Status.MISSING;
  3619.           somePartialSegmentWithGap = true;
  3620.         }
  3622.         let uris = null;
  3623.         const getPartialUris = () => {
  3624.           if (uris == null) {
  3625.             goog.asserts.assert(pUri, 'Partial uri should be defined!');
  3626.             uris = shaka.hls.Utils.constructSegmentUris(
  3627.                 getUris(), pUri, variables);
  3628.           }
  3629.           return uris;
  3630.         };
  3632.         if (byterangeOptimizationSupport &&
  3633.             pStartByte >= 0 && pEndByte != null) {
  3634.           getUrisOptimization = getPartialUris;
  3635.           segmentWithByteRangeOptimization = true;
  3636.         }
  3638.         const partial = new shaka.media.SegmentReference(
  3639.             pStartTime,
  3640.             pEndTime,
  3641.             getPartialUris,
  3642.             pStartByte,
  3643.             pEndByte,
  3644.             initSegmentReference,
  3645.             /* timestampOffset= */ 0,
  3646.             /* appendWindowStart= */ 0,
  3647.             /* appendWindowEnd= */ Infinity,
  3648.             /* partialReferences= */ [],
  3649.             /* tilesLayout= */ '',
  3650.             /* tileDuration= */ null,
  3651.             partialSyncTime,
  3652.             partialStatus,
  3653.             aesKey);
  3654.         if (item.name == 'EXT-X-PRELOAD-HINT') {
  3655.           partial.markAsPreload();
  3656.           isPreloadSegment = true;
  3657.         }
  3658.         // The spec doesn't say that we can assume INDEPENDENT=YES for the
  3659.         // first partial segment. It does call the flag "optional", though, and
  3660.         // that cases where there are no such flags on any partial segments, it
  3661.         // is sensible to assume the first one is independent.
  3662.         if (item.getAttributeValue('INDEPENDENT') != 'YES' && i > 0) {
  3663.           partial.markAsNonIndependent();
  3664.         }
  3666.         const pMimeType = getMimeType(pUri);
  3667.         if (pMimeType) {
  3668.           partial.mimeType = pMimeType;
  3669.           if (HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_.has(pMimeType)) {
  3670.             partial.initSegmentReference = null;
  3671.           }
  3672.         }
  3673.         partialSegmentRefs.push(partial);
  3675.         if (partialSyncTime) {
  3676.           partialSyncTime += pDuration;
  3677.         }
  3678.       } // for-loop of hlsSegment.partialSegments
  3679.     }
  3681.     // If the segment has EXTINF tag, set the segment's end time, start byte
  3682.     // and end byte based on the duration and byterange information.
  3683.     // Otherwise, calculate the end time, start / end byte based on its partial
  3684.     // segments.
  3685.     // Note that the sum of partial segments durations may be slightly different
  3686.     // from the parent segment's duration. In this case, use the duration from
  3687.     // the parent segment tag.
  3688.     if (extinfTag) {
  3689.       // The EXTINF tag format is '#EXTINF:<duration>,[<title>]'.
  3690.       // We're interested in the duration part.
  3691.       const extinfValues = extinfTag.value.split(',');
  3692.       const duration = Number(extinfValues[0]);
  3693.       // Skip segments without duration
  3694.       if (duration == 0) {
  3695.         return null;
  3696.       }
  3697.       endTime = startTime + duration;
  3698.     } else if (partialSegmentRefs.length) {
  3699.       endTime = partialSegmentRefs[partialSegmentRefs.length - 1].endTime;
  3700.     } else {
  3701.       // Skip segments without duration and without partialsegments
  3702.       return null;
  3703.     }
  3705.     if (segmentWithByteRangeOptimization) {
  3706.       // We cannot optimize segments with gaps, or with a start byte that is
  3707.       // not 0.
  3708.       if (somePartialSegmentWithGap || partialSegmentRefs[0].startByte != 0) {
  3709.         segmentWithByteRangeOptimization = false;
  3710.         getUrisOptimization = null;
  3711.       } else {
  3712.         partialSegmentRefs = [];
  3713.       }
  3714.     }
  3716.     // If the segment has EXT-X-BYTERANGE tag, set the start byte and end byte
  3717.     // base on the byterange information. If segment has no EXT-X-BYTERANGE tag
  3718.     // and has partial segments, set the start byte and end byte base on the
  3719.     // partial segments.
  3720.     const byterangeTag =
  3721.          shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-BYTERANGE');
  3722.     if (byterangeTag) {
  3723.       [startByte, endByte] =
  3724.           this.parseByteRange_(previousReference, byterangeTag.value);
  3725.     } else if (partialSegmentRefs.length) {
  3726.       startByte = partialSegmentRefs[0].startByte;
  3727.       endByte = partialSegmentRefs[partialSegmentRefs.length - 1].endByte;
  3728.     }
  3730.     let tilesLayout = '';
  3731.     let tileDuration = null;
  3732.     if (type == shaka.util.ManifestParserUtils.ContentType.IMAGE) {
  3733.       // By default in HLS the tilesLayout is 1x1
  3734.       tilesLayout = '1x1';
  3735.       const tilesTag =
  3736.           shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-TILES');
  3737.       if (tilesTag) {
  3738.         tilesLayout = tilesTag.getRequiredAttrValue('LAYOUT');
  3739.         const duration = tilesTag.getAttributeValue('DURATION');
  3740.         if (duration) {
  3741.           tileDuration = Number(duration);
  3742.         }
  3743.       }
  3744.     }
  3746.     let uris = null;
  3747.     const getSegmentUris = () => {
  3748.       if (getUrisOptimization) {
  3749.         return getUrisOptimization();
  3750.       }
  3751.       if (uris == null) {
  3752.         uris = shaka.hls.Utils.constructSegmentUris(getUris(),
  3753.             hlsSegment.verbatimSegmentUri, variables);
  3754.       }
  3755.       return uris || [];
  3756.     };
  3758.     const allPartialSegments = partialSegmentRefs.length > 0 &&
  3759.         !!hlsSegment.verbatimSegmentUri;
  3761.     const reference = new shaka.media.SegmentReference(
  3762.         startTime,
  3763.         endTime,
  3764.         getSegmentUris,
  3765.         startByte,
  3766.         endByte,
  3767.         initSegmentReference,
  3768.         /* timestampOffset= */ 0,
  3769.         /* appendWindowStart= */ 0,
  3770.         /* appendWindowEnd= */ Infinity,
  3771.         partialSegmentRefs,
  3772.         tilesLayout,
  3773.         tileDuration,
  3774.         syncTime,
  3775.         status,
  3776.         aesKey,
  3777.         allPartialSegments,
  3778.     );
  3780.     const mimeType = getMimeType(hlsSegment.verbatimSegmentUri);
  3781.     if (mimeType) {
  3782.       reference.mimeType = mimeType;
  3783.       if (HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_.has(mimeType)) {
  3784.         reference.initSegmentReference = null;
  3785.       }
  3786.     }
  3788.     if (segmentWithByteRangeOptimization) {
  3789.       this.lowLatencyByterangeOptimization_ = true;
  3790.       reference.markAsByterangeOptimization();
  3792.       if (isPreloadSegment) {
  3793.         reference.markAsPreload();
  3794.       }
  3795.     }
  3797.     return reference;
  3798.   }
  3801.   /**
  3802.    * Parse the startByte and endByte.
  3803.    * @param {shaka.media.SegmentReference} previousReference
  3804.    * @param {?string} byterange
  3805.    * @return {!Array.<number>} An array with the start byte and end byte.
  3806.    * @private
  3807.    */
  3808.   parseByteRange_(previousReference, byterange) {
  3809.     let startByte = 0;
  3810.     let endByte = null;
  3811.     // If BYTERANGE is not specified, the segment consists of the entire
  3812.     // resource.
  3813.     if (byterange) {
  3814.       const blocks = byterange.split('@');
  3815.       const byteLength = Number(blocks[0]);
  3816.       if (blocks[1]) {
  3817.         startByte = Number(blocks[1]);
  3818.       } else {
  3819.         goog.asserts.assert(previousReference,
  3820.             'Cannot refer back to previous HLS segment!');
  3821.         startByte = previousReference.endByte + 1;
  3822.       }
  3823.       endByte = startByte + byteLength - 1;
  3824.     }
  3825.     return [startByte, endByte];
  3826.   }
  3828.   /**
  3829.    * @param {!Array.<!shaka.hls.Tag>} tags
  3830.    * @param {string} contentType
  3831.    * @param {!Map.<string, string>} variables
  3832.    * @param {function():!Array.<string>} getUris
  3833.    * @private
  3834.    */
  3835.   processDateRangeTags_(tags, contentType, variables, getUris) {
  3836.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  3837.     if (contentType != ContentType.VIDEO && contentType != ContentType.AUDIO) {
  3838.       // DATE-RANGE should only appear in AUDIO or VIDEO playlists.
  3839.       // We ignore those that appear in other playlists.
  3840.       return;
  3841.     }
  3842.     const Utils = shaka.hls.Utils;
  3843.     const initialProgramDateTime =
  3844.         this.presentationTimeline_.getInitialProgramDateTime();
  3845.     if (!initialProgramDateTime ||
  3846.         this.ignoreManifestProgramDateTimeFor_(contentType)) {
  3847.       return;
  3848.     }
  3849.     let dateRangeTags =
  3850.         shaka.hls.Utils.filterTagsByName(tags, 'EXT-X-DATERANGE');
  3851.     dateRangeTags = dateRangeTags.sort((a, b) => {
  3852.       const aStartDateValue = a.getRequiredAttrValue('START-DATE');
  3853.       const bStartDateValue = b.getRequiredAttrValue('START-DATE');
  3854.       if (aStartDateValue < bStartDateValue) {
  3855.         return -1;
  3856.       }
  3857.       if (aStartDateValue > bStartDateValue) {
  3858.         return 1;
  3859.       }
  3860.       return 0;
  3861.     });
  3862.     for (let i = 0; i < dateRangeTags.length; i++) {
  3863.       const tag = dateRangeTags[i];
  3864.       const id = tag.getRequiredAttrValue('ID');
  3865.       if (this.dateRangeIdsEmitted_.has(id)) {
  3866.         continue;
  3867.       }
  3868.       const startDateValue = tag.getRequiredAttrValue('START-DATE');
  3869.       const startDate = shaka.util.TXml.parseDate(startDateValue);
  3870.       if (isNaN(startDate)) {
  3871.         // Invalid START-DATE
  3872.         continue;
  3873.       }
  3874.       goog.asserts.assert(startDate != null, 'Start date should not be null!');
  3875.       const startTime = Math.max(0, startDate - initialProgramDateTime);
  3877.       let endTime = null;
  3878.       const endDateValue = tag.getAttributeValue('END-DATE');
  3879.       if (endDateValue) {
  3880.         const endDate = shaka.util.TXml.parseDate(endDateValue);
  3881.         if (!isNaN(endDate)) {
  3882.           goog.asserts.assert(endDate != null, 'End date should not be null!');
  3883.           endTime = endDate - initialProgramDateTime;
  3884.           if (endTime < 0) {
  3885.             // Date range in the past
  3886.             continue;
  3887.           }
  3888.         }
  3889.       }
  3890.       if (endTime == null) {
  3891.         const durationValue = tag.getAttributeValue('DURATION') ||
  3892.             tag.getAttributeValue('PLANNED-DURATION');
  3893.         if (durationValue) {
  3894.           const duration = parseFloat(durationValue);
  3895.           if (!isNaN(duration)) {
  3896.             endTime = startTime + duration;
  3897.           }
  3898.           const realEndTime = startDate - initialProgramDateTime + duration;
  3899.           if (realEndTime < 0) {
  3900.             // Date range in the past
  3901.             continue;
  3902.           }
  3903.         }
  3904.       }
  3905.       const type = tag.getAttributeValue('CLASS') || 'com.apple.quicktime.HLS';
  3907.       const endOnNext = tag.getAttributeValue('END-ON-NEXT') == 'YES';
  3908.       if (endTime == null && endOnNext) {
  3909.         for (let j = i + 1; j < dateRangeTags.length; j++) {
  3910.           const otherDateRangeType =
  3911.               dateRangeTags[j].getAttributeValue('CLASS') ||
  3912.               'com.apple.quicktime.HLS';
  3913.           if (type != otherDateRangeType) {
  3914.             continue;
  3915.           }
  3916.           const otherDateRangeStartDateValue =
  3917.               dateRangeTags[j].getRequiredAttrValue('START-DATE');
  3918.           const otherDateRangeStartDate =
  3919.               shaka.util.TXml.parseDate(otherDateRangeStartDateValue);
  3920.           if (isNaN(otherDateRangeStartDate)) {
  3921.             // Invalid START-DATE
  3922.             continue;
  3923.           }
  3924.           if (otherDateRangeStartDate && otherDateRangeStartDate > startDate) {
  3925.             endTime = Math.max(0,
  3926.                 otherDateRangeStartDate - initialProgramDateTime);
  3927.             break;
  3928.           }
  3929.         }
  3930.         if (endTime == null) {
  3931.           // Since we cannot know when it ends, we omit it for now and in the
  3932.           // future with an update we will be able to have more information.
  3933.           continue;
  3934.         }
  3935.       }
  3937.       // Exclude these attributes from the metadata since they already go into
  3938.       // other fields (eg: startTime or endTime) or are not necessary..
  3939.       const excludedAttributes = [
  3940.         'ID',
  3941.         'CLASS',
  3942.         'START-DATE',
  3943.         'END-DATE',
  3944.         'DURATION',
  3945.         'END-ON-NEXT',
  3946.       ];
  3948.       /* @type {!Array.<shaka.extern.MetadataFrame>} */
  3949.       const values = [];
  3950.       for (const attribute of tag.attributes) {
  3951.         if (excludedAttributes.includes(attribute.name)) {
  3952.           continue;
  3953.         }
  3954.         let data = Utils.variableSubstitution(attribute.value, variables);
  3955.         if (attribute.name == 'X-ASSET-URI' ||
  3956.             attribute.name == 'X-ASSET-LIST') {
  3957.           data = Utils.constructSegmentUris(
  3958.               getUris(), attribute.value, variables)[0];
  3959.         }
  3960.         const metadataFrame = {
  3961.           key: attribute.name,
  3962.           description: '',
  3963.           data,
  3964.           mimeType: null,
  3965.           pictureType: null,
  3966.         };
  3967.         values.push(metadataFrame);
  3968.       }
  3970.       if (values.length) {
  3971.         this.playerInterface_.onMetadata(type, startTime, endTime, values);
  3972.       }
  3974.       this.dateRangeIdsEmitted_.add(id);
  3975.     }
  3976.   }
  3978.   /**
  3979.    * Parses shaka.hls.Segment objects into shaka.media.SegmentReferences and
  3980.    * get the bandwidth necessary for this segments If it's defined in the
  3981.    * playlist.
  3982.    *
  3983.    * @param {!shaka.hls.Playlist} playlist
  3984.    * @param {!Map.<number, number>} mediaSequenceToStartTime
  3985.    * @param {!Map.<string, string>} variables
  3986.    * @param {function():!Array.<string>} getUris
  3987.    * @param {string} type
  3988.    * @return {{segments: !Array.<!shaka.media.SegmentReference>,
  3989.    *          bandwidth: (number|undefined)}}
  3990.    * @private
  3991.    */
  3992.   createSegments_(playlist, mediaSequenceToStartTime, variables,
  3993.       getUris, type) {
  3994.     /** @type {Array.<!shaka.hls.Segment>} */
  3995.     const hlsSegments = playlist.segments;
  3996.     goog.asserts.assert(hlsSegments.length, 'Playlist should have segments!');
  3998.     /** @type {shaka.media.InitSegmentReference} */
  3999.     let initSegmentRef;
  4001.     /** @type {shaka.extern.aesKey|undefined} */
  4002.     let aesKey = undefined;
  4004.     let discontinuitySequence = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4005.         playlist.tags, 'EXT-X-DISCONTINUITY-SEQUENCE', 0);
  4006.     const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4007.         playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  4008.     const skipTag = shaka.hls.Utils.getFirstTagWithName(
  4009.         playlist.tags, 'EXT-X-SKIP');
  4010.     const skippedSegments =
  4011.         skipTag ? Number(skipTag.getAttributeValue('SKIPPED-SEGMENTS')) : 0;
  4012.     let position = mediaSequenceNumber + skippedSegments;
  4013.     let firstStartTime = 0;
  4015.     // For live stream, use the cached value in the mediaSequenceToStartTime
  4016.     // map if available.
  4017.     if (this.isLive_() && mediaSequenceToStartTime.has(position)) {
  4018.       firstStartTime = mediaSequenceToStartTime.get(position);
  4019.     }
  4020.     // This is for recovering from disconnects.
  4021.     if (firstStartTime === 0 &&
  4022.         this.presentationType_ == shaka.hls.HlsParser.PresentationType_.LIVE &&
  4023.         mediaSequenceToStartTime.size > 0 &&
  4024.         !mediaSequenceToStartTime.has(position)) {
  4025.       firstStartTime = this.presentationTimeline_.getSegmentAvailabilityStart();
  4026.     }
  4028.     /** @type {!Array.<!shaka.media.SegmentReference>} */
  4029.     const references = [];
  4031.     let previousReference = null;
  4033.     /** @type {!Array.<{bitrate: number, duration: number}>} */
  4034.     const bitrates = [];
  4036.     for (let i = 0; i < hlsSegments.length; i++) {
  4037.       const item = hlsSegments[i];
  4038.       const startTime =
  4039.           (i == 0) ? firstStartTime : previousReference.endTime;
  4040.       position = mediaSequenceNumber + skippedSegments + i;
  4042.       const discontinuityTag = shaka.hls.Utils.getFirstTagWithName(
  4043.           item.tags, 'EXT-X-DISCONTINUITY');
  4044.       if (discontinuityTag) {
  4045.         discontinuitySequence++;
  4046.       }
  4048.       // Apply new AES tags as you see them, keeping a running total.
  4049.       for (const drmTag of item.tags) {
  4050.         if (drmTag.name == 'EXT-X-KEY') {
  4051.           if (this.isAesMethod_(drmTag.getRequiredAttrValue('METHOD'))) {
  4052.             aesKey =
  4053.                 this.parseAESDrmTag_(drmTag, playlist, getUris, variables);
  4054.           } else {
  4055.             aesKey = undefined;
  4056.           }
  4057.         }
  4058.       }
  4060.       mediaSequenceToStartTime.set(position, startTime);
  4062.       initSegmentRef = this.getInitSegmentReference_(playlist,
  4063.           item.tags, getUris, variables);
  4065.       // If the stream is low latency and the user has not configured the
  4066.       // lowLatencyMode, but if it has been configured to activate the
  4067.       // lowLatencyMode if a stream of this type is detected, we automatically
  4068.       // activate the lowLatencyMode.
  4069.       if (!this.lowLatencyMode_) {
  4070.         const autoLowLatencyMode = this.playerInterface_.isAutoLowLatencyMode();
  4071.         if (autoLowLatencyMode) {
  4072.           this.playerInterface_.enableLowLatencyMode();
  4073.           this.lowLatencyMode_ = this.playerInterface_.isLowLatencyMode();
  4074.         }
  4075.       }
  4077.       const reference = this.createSegmentReference_(
  4078.           initSegmentRef,
  4079.           previousReference,
  4080.           item,
  4081.           startTime,
  4082.           variables,
  4083.           playlist,
  4084.           type,
  4085.           getUris,
  4086.           aesKey);
  4088.       if (reference) {
  4089.         const bitrate = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4090.             item.tags, 'EXT-X-BITRATE');
  4091.         if (bitrate) {
  4092.           bitrates.push({
  4093.             bitrate,
  4094.             duration: reference.endTime - reference.startTime,
  4095.           });
  4096.         } else if (bitrates.length) {
  4097.           // It applies to every segment between it and the next EXT-X-BITRATE,
  4098.           // so we use the latest bitrate value
  4099.           const prevBitrate = bitrates.pop();
  4100.           prevBitrate.duration += reference.endTime - reference.startTime;
  4101.           bitrates.push(prevBitrate);
  4102.         }
  4104.         previousReference = reference;
  4105.         reference.discontinuitySequence = discontinuitySequence;
  4107.         if (this.ignoreManifestProgramDateTimeFor_(type) &&
  4108.             this.minSequenceNumber_ != null &&
  4109.             position < this.minSequenceNumber_) {
  4110.           // This segment is ignored as part of our fallback synchronization
  4111.           // method.
  4112.         } else {
  4113.           references.push(reference);
  4114.         }
  4115.       }
  4116.     }
  4118.     let bandwidth = undefined;
  4119.     if (bitrates.length) {
  4120.       const duration = bitrates.reduce((sum, value) => {
  4121.         return sum + value.duration;
  4122.       }, 0);
  4123.       bandwidth = Math.round(bitrates.reduce((sum, value) => {
  4124.         return sum + value.bitrate * value.duration;
  4125.       }, 0) / duration * 1000);
  4126.     }
  4128.     // If some segments have sync times, but not all, extrapolate the sync
  4129.     // times of the ones with none.
  4130.     const someSyncTime = references.some((ref) => ref.syncTime != null);
  4131.     if (someSyncTime) {
  4132.       for (let i = 0; i < references.length; i++) {
  4133.         const reference = references[i];
  4134.         if (reference.syncTime != null) {
  4135.           // No need to extrapolate.
  4136.           continue;
  4137.         }
  4138.         // Find the nearest segment with syncTime, in either direction.
  4139.         // This looks forward and backward simultaneously, keeping track of what
  4140.         // to offset the syncTime it finds by as it goes.
  4141.         let forwardAdd = 0;
  4142.         let forwardI = i;
  4143.         /**
  4144.          * Look forwards one reference at a time, summing all durations as we
  4145.          * go, until we find a reference with a syncTime to use as a basis.
  4146.          * This DOES count the original reference, but DOESN'T count the first
  4147.          * reference with a syncTime (as we approach it from behind).
  4148.          * @return {?number}
  4149.          */
  4150.         const lookForward = () => {
  4151.           const other = references[forwardI];
  4152.           if (other) {
  4153.             if (other.syncTime != null) {
  4154.               return other.syncTime + forwardAdd;
  4155.             }
  4156.             forwardAdd -= other.endTime - other.startTime;
  4157.             forwardI += 1;
  4158.           }
  4159.           return null;
  4160.         };
  4161.         let backwardAdd = 0;
  4162.         let backwardI = i;
  4163.         /**
  4164.          * Look backwards one reference at a time, summing all durations as we
  4165.          * go, until we find a reference with a syncTime to use as a basis.
  4166.          * This DOESN'T count the original reference, but DOES count the first
  4167.          * reference with a syncTime (as we approach it from ahead).
  4168.          * @return {?number}
  4169.          */
  4170.         const lookBackward = () => {
  4171.           const other = references[backwardI];
  4172.           if (other) {
  4173.             if (other != reference) {
  4174.               backwardAdd += other.endTime - other.startTime;
  4175.             }
  4176.             if (other.syncTime != null) {
  4177.               return other.syncTime + backwardAdd;
  4178.             }
  4179.             backwardI -= 1;
  4180.           }
  4181.           return null;
  4182.         };
  4183.         while (reference.syncTime == null) {
  4184.           reference.syncTime = lookBackward();
  4185.           if (reference.syncTime == null) {
  4186.             reference.syncTime = lookForward();
  4187.           }
  4188.         }
  4189.       }
  4190.     }
  4192.     // Split the sync times properly among partial segments.
  4193.     if (someSyncTime) {
  4194.       for (const reference of references) {
  4195.         let syncTime = reference.syncTime;
  4196.         for (const partial of reference.partialReferences) {
  4197.           partial.syncTime = syncTime;
  4198.           syncTime += partial.endTime - partial.startTime;
  4199.         }
  4200.       }
  4201.     }
  4203.     // lowestSyncTime is a value from a previous playlist update.  Use it to
  4204.     // set reference start times.  If this is the first playlist parse, we will
  4205.     // skip this step, and wait until we have sync time across stream types.
  4206.     const lowestSyncTime = this.lowestSyncTime_;
  4207.     if (someSyncTime && lowestSyncTime != Infinity) {
  4208.       if (!this.ignoreManifestProgramDateTimeFor_(type)) {
  4209.         for (const reference of references) {
  4210.           reference.syncAgainst(lowestSyncTime);
  4211.         }
  4212.       }
  4213.     }
  4215.     return {
  4216.       segments: references,
  4217.       bandwidth,
  4218.     };
  4219.   }
  4221.   /**
  4222.    * Attempts to guess stream's mime type based on content type and URI.
  4223.    *
  4224.    * @param {string} contentType
  4225.    * @param {string} codecs
  4226.    * @return {?string}
  4227.    * @private
  4228.    */
  4229.   guessMimeTypeBeforeLoading_(contentType, codecs) {
  4230.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  4231.       if (codecs == 'vtt' || codecs == 'wvtt') {
  4232.         // If codecs is 'vtt', it's WebVTT.
  4233.         return 'text/vtt';
  4234.       } else if (codecs && codecs !== '') {
  4235.         // Otherwise, assume MP4-embedded text, since text-based formats tend
  4236.         // not to have a codecs string at all.
  4237.         return 'application/mp4';
  4238.       }
  4239.     }
  4241.     if (contentType == shaka.util.ManifestParserUtils.ContentType.IMAGE) {
  4242.       if (!codecs || codecs == 'jpeg') {
  4243.         return 'image/jpeg';
  4244.       }
  4245.     }
  4247.     if (contentType == shaka.util.ManifestParserUtils.ContentType.AUDIO) {
  4248.       // See: https://bugs.chromium.org/p/chromium/issues/detail?id=489520
  4249.       if (codecs == 'mp4a.40.34') {
  4250.         return 'audio/mpeg';
  4251.       }
  4252.     }
  4254.     if (codecs == 'mjpg') {
  4255.       return 'application/mp4';
  4256.     }
  4258.     // Not enough information to guess from the content type and codecs.
  4259.     return null;
  4260.   }
  4262.   /**
  4263.    * Get a fallback mime type for the content. Used if all the better methods
  4264.    * for determining the mime type have failed.
  4265.    *
  4266.    * @param {string} contentType
  4267.    * @return {string}
  4268.    * @private
  4269.    */
  4270.   guessMimeTypeFallback_(contentType) {
  4271.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  4272.       // If there was no codecs string and no content-type, assume HLS text
  4273.       // streams are WebVTT.
  4274.       return 'text/vtt';
  4275.     }
  4276.     // If the HLS content is lacking in both MIME type metadata and
  4277.     // segment file extensions, we fall back to assuming it's MP4.
  4278.     const map = shaka.hls.HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_[contentType];
  4279.     return map['mp4'];
  4280.   }
  4282.   /**
  4283.    * @param {!Array.<!shaka.media.SegmentReference>} segments
  4284.    * @return {{segment: !shaka.media.SegmentReference, segmentIndex: number}}
  4285.    * @private
  4286.    */
  4287.   getAvailableSegment_(segments) {
  4288.     goog.asserts.assert(segments.length, 'Should have segments!');
  4290.     // If you wait long enough, requesting the first segment can fail
  4291.     // because it has fallen off the left edge of DVR, so to be safer,
  4292.     // let's request the middle segment.
  4293.     let segmentIndex = this.isLive_() ?
  4294.         Math.trunc((segments.length - 1) / 2) : 0;
  4295.     let segment = segments[segmentIndex];
  4296.     while (segment.getStatus() == shaka.media.SegmentReference.Status.MISSING &&
  4297.         (segmentIndex + 1) < segments.length) {
  4298.       segmentIndex ++;
  4299.       segment = segments[segmentIndex];
  4300.     }
  4301.     return {segment, segmentIndex};
  4302.   }
  4304.   /**
  4305.    * Attempts to guess stream's mime type.
  4306.    *
  4307.    * @param {string} contentType
  4308.    * @param {string} codecs
  4309.    * @param {!Array.<!shaka.media.SegmentReference>} segments
  4310.    * @return {!Promise.<string>}
  4311.    * @private
  4312.    */
  4313.   async guessMimeType_(contentType, codecs, segments) {
  4314.     const HlsParser = shaka.hls.HlsParser;
  4315.     const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  4317.     const {segment} = this.getAvailableSegment_(segments);
  4319.     if (segment.status == shaka.media.SegmentReference.Status.MISSING) {
  4320.       return this.guessMimeTypeFallback_(contentType);
  4321.     }
  4323.     const segmentUris = segment.getUris();
  4325.     const parsedUri = new goog.Uri(segmentUris[0]);
  4326.     const extension = parsedUri.getPath().split('.').pop();
  4327.     const map = HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_[contentType];
  4329.     let mimeType = map[extension];
  4330.     if (mimeType) {
  4331.       return mimeType;
  4332.     }
  4334.     mimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_[extension];
  4335.     if (mimeType) {
  4336.       return mimeType;
  4337.     }
  4339.     // The extension map didn't work, so guess based on codecs.
  4340.     mimeType = this.guessMimeTypeBeforeLoading_(contentType, codecs);
  4341.     if (mimeType) {
  4342.       return mimeType;
  4343.     }
  4345.     // If unable to guess mime type, request a segment and try getting it
  4346.     // from the response.
  4347.     let contentMimeType;
  4348.     const type = shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_SEGMENT;
  4349.     const headRequest = shaka.net.NetworkingEngine.makeRequest(
  4350.         segmentUris, this.config_.retryParameters);
  4351.     try {
  4352.       headRequest.method = 'HEAD';
  4353.       const response = await this.makeNetworkRequest_(
  4354.           headRequest, requestType, {type});
  4356.       contentMimeType = response.headers['content-type'];
  4357.     } catch (error) {
  4358.       if (error &&
  4359.         (error.code == shaka.util.Error.Code.HTTP_ERROR ||
  4360.          error.code == shaka.util.Error.Code.BAD_HTTP_STATUS)) {
  4361.         headRequest.method = 'GET';
  4362.         const response = await this.makeNetworkRequest_(
  4363.             headRequest, requestType, {type});
  4365.         contentMimeType = response.headers['content-type'];
  4366.       }
  4367.     }
  4369.     if (contentMimeType) {
  4370.       // Split the MIME type in case the server sent additional parameters.
  4371.       return contentMimeType.toLowerCase().split(';')[0];
  4372.     }
  4374.     return this.guessMimeTypeFallback_(contentType);
  4375.   }
  4377.   /**
  4378.    * Returns a tag with a given name.
  4379.    * Throws an error if tag was not found.
  4380.    *
  4381.    * @param {!Array.<shaka.hls.Tag>} tags
  4382.    * @param {string} tagName
  4383.    * @return {!shaka.hls.Tag}
  4384.    * @private
  4385.    */
  4386.   getRequiredTag_(tags, tagName) {
  4387.     const tag = shaka.hls.Utils.getFirstTagWithName(tags, tagName);
  4388.     if (!tag) {
  4389.       throw new shaka.util.Error(
  4390.           shaka.util.Error.Severity.CRITICAL,
  4391.           shaka.util.Error.Category.MANIFEST,
  4392.           shaka.util.Error.Code.HLS_REQUIRED_TAG_MISSING, tagName);
  4393.     }
  4395.     return tag;
  4396.   }
  4398.   /**
  4399.    * @param {shaka.extern.Stream} stream
  4400.    * @param {?string} width
  4401.    * @param {?string} height
  4402.    * @param {?string} frameRate
  4403.    * @param {?string} videoRange
  4404.    * @param {?string} videoLayout
  4405.    * @param {?string} colorGamut
  4406.    * @private
  4407.    */
  4408.   addVideoAttributes_(stream, width, height, frameRate, videoRange,
  4409.       videoLayout, colorGamut) {
  4410.     if (stream) {
  4411.       stream.width = Number(width) || undefined;
  4412.       stream.height = Number(height) || undefined;
  4413.       stream.frameRate = Number(frameRate) || undefined;
  4414.       stream.hdr = videoRange || undefined;
  4415.       stream.videoLayout = videoLayout || undefined;
  4416.       stream.colorGamut = colorGamut || undefined;
  4417.     }
  4418.   }
  4420.   /**
  4421.    * Makes a network request for the manifest and returns a Promise
  4422.    * with the resulting data.
  4423.    *
  4424.    * @param {!Array.<string>} uris
  4425.    * @param {boolean=} isPlaylist
  4426.    * @return {!Promise.<!shaka.extern.Response>}
  4427.    * @private
  4428.    */
  4429.   requestManifest_(uris, isPlaylist) {
  4430.     const requestType = shaka.net.NetworkingEngine.RequestType.MANIFEST;
  4432.     const request = shaka.net.NetworkingEngine.makeRequest(
  4433.         uris, this.config_.retryParameters);
  4435.     const type = isPlaylist ?
  4436.         shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_PLAYLIST :
  4437.         shaka.net.NetworkingEngine.AdvancedRequestType.MASTER_PLAYLIST;
  4438.     return this.makeNetworkRequest_(request, requestType, {type});
  4439.   }
  4441.   /**
  4442.    * Called when the update timer ticks. Because parsing a manifest is async,
  4443.    * this method is async. To work with this, this method will schedule the next
  4444.    * update when it finished instead of using a repeating-start.
  4445.    *
  4446.    * @return {!Promise}
  4447.    * @private
  4448.    */
  4449.   async onUpdate_() {
  4450.     shaka.log.info('Updating manifest...');
  4452.     goog.asserts.assert(
  4453.         this.getUpdatePlaylistDelay_() > 0,
  4454.         'We should only call |onUpdate_| when we are suppose to be updating.');
  4456.     // Detect a call to stop()
  4457.     if (!this.playerInterface_) {
  4458.       return;
  4459.     }
  4461.     try {
  4462.       const startTime = Date.now();
  4463.       await this.update();
  4465.       // Keep track of how long the longest manifest update took.
  4466.       const endTime = Date.now();
  4468.       // This may have converted to VOD, in which case we stop updating.
  4469.       if (this.isLive_()) {
  4470.         const updateDuration = (endTime - startTime) / 1000.0;
  4471.         this.averageUpdateDuration_.sample(1, updateDuration);
  4472.         const delay = this.getUpdatePlaylistDelay_();
  4473.         const finalDelay = Math.max(0,
  4474.             delay - this.averageUpdateDuration_.getEstimate());
  4475.         this.updatePlaylistTimer_.tickAfter(/* seconds= */ finalDelay);
  4476.       }
  4477.     } catch (error) {
  4478.       // Detect a call to stop() during this.update()
  4479.       if (!this.playerInterface_) {
  4480.         return;
  4481.       }
  4483.       goog.asserts.assert(error instanceof shaka.util.Error,
  4484.           'Should only receive a Shaka error');
  4486.       if (this.config_.raiseFatalErrorOnManifestUpdateRequestFailure) {
  4487.         this.playerInterface_.onError(error);
  4488.         return;
  4489.       }
  4491.       // We will retry updating, so override the severity of the error.
  4492.       error.severity = shaka.util.Error.Severity.RECOVERABLE;
  4493.       this.playerInterface_.onError(error);
  4495.       // Try again very soon.
  4496.       this.updatePlaylistTimer_.tickAfter(/* seconds= */ 0.1);
  4497.     }
  4499.     // Detect a call to stop()
  4500.     if (!this.playerInterface_) {
  4501.       return;
  4502.     }
  4504.     this.playerInterface_.onManifestUpdated();
  4505.   }
  4508.   /**
  4509.    * @return {boolean}
  4510.    * @private
  4511.    */
  4512.   isLive_() {
  4513.     const PresentationType = shaka.hls.HlsParser.PresentationType_;
  4514.     return this.presentationType_ != PresentationType.VOD;
  4515.   }
  4518.   /**
  4519.    * @return {number}
  4520.    * @private
  4521.    */
  4522.   getUpdatePlaylistDelay_() {
  4523.     // The HLS spec (RFC 8216) states in 6.3.4:
  4524.     // "the client MUST wait for at least the target duration before
  4525.     // attempting to reload the Playlist file again".
  4526.     // For LL-HLS, the server must add a new partial segment to the Playlist
  4527.     // every part target duration.
  4528.     return this.lastTargetDuration_;
  4529.   }
  4532.   /**
  4533.    * @param {shaka.hls.HlsParser.PresentationType_} type
  4534.    * @private
  4535.    */
  4536.   setPresentationType_(type) {
  4537.     this.presentationType_ = type;
  4539.     if (this.presentationTimeline_) {
  4540.       this.presentationTimeline_.setStatic(!this.isLive_());
  4541.     }
  4543.     // If this manifest is not for live content, then we have no reason to
  4544.     // update it.
  4545.     if (!this.isLive_()) {
  4546.       this.updatePlaylistTimer_.stop();
  4547.     }
  4548.   }
  4551.   /**
  4552.    * Create a networking request. This will manage the request using the
  4553.    * parser's operation manager. If the parser has already been stopped, the
  4554.    * request will not be made.
  4555.    *
  4556.    * @param {shaka.extern.Request} request
  4557.    * @param {shaka.net.NetworkingEngine.RequestType} type
  4558.    * @param {shaka.extern.RequestContext=} context
  4559.    * @return {!Promise.<shaka.extern.Response>}
  4560.    * @private
  4561.    */
  4562.   makeNetworkRequest_(request, type, context) {
  4563.     if (!this.operationManager_) {
  4564.       throw new shaka.util.Error(
  4565.           shaka.util.Error.Severity.CRITICAL,
  4566.           shaka.util.Error.Category.PLAYER,
  4567.           shaka.util.Error.Code.OPERATION_ABORTED);
  4568.     }
  4570.     const op = this.playerInterface_.networkingEngine.request(
  4571.         type, request, context);
  4572.     this.operationManager_.manage(op);
  4574.     return op.promise;
  4575.   }
  4577.   /**
  4578.    * @param {string} method
  4579.    * @return {boolean}
  4580.    * @private
  4581.    */
  4582.   isAesMethod_(method) {
  4583.     return method == 'AES-128' ||
  4584.         method == 'AES-256' ||
  4585.         method == 'AES-256-CTR';
  4586.   }
  4588.   /**
  4589.    * @param {!shaka.hls.Tag} drmTag
  4590.    * @param {string} mimeType
  4591.    * @return {?shaka.extern.DrmInfo}
  4592.    * @private
  4593.    */
  4594.   static fairplayDrmParser_(drmTag, mimeType) {
  4595.     if (mimeType == 'video/mp2t') {
  4596.       throw new shaka.util.Error(
  4597.           shaka.util.Error.Severity.CRITICAL,
  4598.           shaka.util.Error.Category.MANIFEST,
  4599.           shaka.util.Error.Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
  4600.     }
  4602.     if (shaka.util.Platform.isMediaKeysPolyfilled()) {
  4603.       throw new shaka.util.Error(
  4604.           shaka.util.Error.Severity.CRITICAL,
  4605.           shaka.util.Error.Category.MANIFEST,
  4606.           shaka.util.Error.Code
  4607.               .HLS_MSE_ENCRYPTED_LEGACY_APPLE_MEDIA_KEYS_NOT_SUPPORTED);
  4608.     }
  4610.     const method = drmTag.getRequiredAttrValue('METHOD');
  4611.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4612.     if (!VALID_METHODS.includes(method)) {
  4613.       shaka.log.error('FairPlay in HLS is only supported with [',
  4614.           VALID_METHODS.join(', '), '], not', method);
  4615.       return null;
  4616.     }
  4618.     let encryptionScheme = 'cenc';
  4619.     if (method == 'SAMPLE-AES') {
  4620.       // It should be 'cbcs-1-9' but Safari doesn't support it.
  4621.       // See: https://github.com/WebKit/WebKit/blob/main/Source/WebCore/Modules/encryptedmedia/MediaKeyEncryptionScheme.idl
  4622.       encryptionScheme = 'cbcs';
  4623.     }
  4625.     /*
  4626.      * Even if we're not able to construct initData through the HLS tag, adding
  4627.      * a DRMInfo will allow DRM Engine to request a media key system access
  4628.      * with the correct keySystem and initDataType
  4629.      */
  4630.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4631.         'com.apple.fps', encryptionScheme, [
  4632.           {initDataType: 'sinf', initData: new Uint8Array(0), keyId: null},
  4633.         ], drmTag.getRequiredAttrValue('URI'));
  4635.     return drmInfo;
  4636.   }
  4638.   /**
  4639.    * @param {!shaka.hls.Tag} drmTag
  4640.    * @return {?shaka.extern.DrmInfo}
  4641.    * @private
  4642.    */
  4643.   static widevineDrmParser_(drmTag) {
  4644.     const method = drmTag.getRequiredAttrValue('METHOD');
  4645.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4646.     if (!VALID_METHODS.includes(method)) {
  4647.       shaka.log.error('Widevine in HLS is only supported with [',
  4648.           VALID_METHODS.join(', '), '], not', method);
  4649.       return null;
  4650.     }
  4652.     let encryptionScheme = 'cenc';
  4653.     if (method == 'SAMPLE-AES') {
  4654.       encryptionScheme = 'cbcs';
  4655.     }
  4657.     const uri = drmTag.getRequiredAttrValue('URI');
  4658.     const parsedData = shaka.net.DataUriPlugin.parseRaw(uri.split('?')[0]);
  4660.     // The data encoded in the URI is a PSSH box to be used as init data.
  4661.     const pssh = shaka.util.BufferUtils.toUint8(parsedData.data);
  4662.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4663.         'com.widevine.alpha', encryptionScheme, [
  4664.           {initDataType: 'cenc', initData: pssh},
  4665.         ]);
  4667.     const keyId = drmTag.getAttributeValue('KEYID');
  4668.     if (keyId) {
  4669.       const keyIdLowerCase = keyId.toLowerCase();
  4670.       // This value should begin with '0x':
  4671.       goog.asserts.assert(
  4672.           keyIdLowerCase.startsWith('0x'), 'Incorrect KEYID format!');
  4673.       // But the output should not contain the '0x':
  4674.       drmInfo.keyIds = new Set([keyIdLowerCase.substr(2)]);
  4675.     }
  4676.     return drmInfo;
  4677.   }
  4679.   /**
  4680.    * See: https://docs.microsoft.com/en-us/playready/packaging/mp4-based-formats-supported-by-playready-clients?tabs=case4
  4681.    *
  4682.    * @param {!shaka.hls.Tag} drmTag
  4683.    * @return {?shaka.extern.DrmInfo}
  4684.    * @private
  4685.    */
  4686.   static playreadyDrmParser_(drmTag) {
  4687.     const method = drmTag.getRequiredAttrValue('METHOD');
  4688.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4689.     if (!VALID_METHODS.includes(method)) {
  4690.       shaka.log.error('PlayReady in HLS is only supported with [',
  4691.           VALID_METHODS.join(', '), '], not', method);
  4692.       return null;
  4693.     }
  4695.     let encryptionScheme = 'cenc';
  4696.     if (method == 'SAMPLE-AES') {
  4697.       encryptionScheme = 'cbcs';
  4698.     }
  4700.     const uri = drmTag.getRequiredAttrValue('URI');
  4701.     const parsedData = shaka.net.DataUriPlugin.parseRaw(uri.split('?')[0]);
  4703.     // The data encoded in the URI is a PlayReady Pro Object, so we need
  4704.     // convert it to pssh.
  4705.     const data = shaka.util.BufferUtils.toUint8(parsedData.data);
  4706.     const systemId = new Uint8Array([
  4707.       0x9a, 0x04, 0xf0, 0x79, 0x98, 0x40, 0x42, 0x86,
  4708.       0xab, 0x92, 0xe6, 0x5b, 0xe0, 0x88, 0x5f, 0x95,
  4709.     ]);
  4710.     const keyIds = new Set();
  4711.     const psshVersion = 0;
  4712.     const pssh =
  4713.         shaka.util.Pssh.createPssh(data, systemId, keyIds, psshVersion);
  4714.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4715.         'com.microsoft.playready', encryptionScheme, [
  4716.           {initDataType: 'cenc', initData: pssh},
  4717.         ]);
  4719.     return drmInfo;
  4720.   }
  4722.   /**
  4723.    * See: https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-5.1
  4724.    *
  4725.    * @param {!shaka.hls.Tag} drmTag
  4726.    * @param {string} mimeType
  4727.    * @param {function():!Array.<string>} getUris
  4728.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  4729.    * @param {?Map.<string, string>=} variables
  4730.    * @return {!Promise.<?shaka.extern.DrmInfo>}
  4731.    * @private
  4732.    */
  4733.   async identityDrmParser_(drmTag, mimeType, getUris, initSegmentRef,
  4734.       variables) {
  4735.     if (mimeType == 'video/mp2t') {
  4736.       throw new shaka.util.Error(
  4737.           shaka.util.Error.Severity.CRITICAL,
  4738.           shaka.util.Error.Category.MANIFEST,
  4739.           shaka.util.Error.Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
  4740.     }
  4742.     if (shaka.util.Platform.isMediaKeysPolyfilled()) {
  4743.       throw new shaka.util.Error(
  4744.           shaka.util.Error.Severity.CRITICAL,
  4745.           shaka.util.Error.Category.MANIFEST,
  4746.           shaka.util.Error.Code
  4747.               .HLS_MSE_ENCRYPTED_LEGACY_APPLE_MEDIA_KEYS_NOT_SUPPORTED);
  4748.     }
  4750.     const method = drmTag.getRequiredAttrValue('METHOD');
  4751.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4752.     if (!VALID_METHODS.includes(method)) {
  4753.       shaka.log.error('Identity (ClearKey) in HLS is only supported with [',
  4754.           VALID_METHODS.join(', '), '], not', method);
  4755.       return null;
  4756.     }
  4758.     const keyUris = shaka.hls.Utils.constructSegmentUris(
  4759.         getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  4761.     let key;
  4762.     if (keyUris[0].startsWith('data:text/plain;base64,')) {
  4763.       key = shaka.util.Uint8ArrayUtils.toHex(
  4764.           shaka.util.Uint8ArrayUtils.fromBase64(
  4765.               keyUris[0].split('data:text/plain;base64,').pop()));
  4766.     } else {
  4767.       const keyMapKey = keyUris.sort().join('');
  4768.       if (!this.identityKeyMap_.has(keyMapKey)) {
  4769.         const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  4770.         const request = shaka.net.NetworkingEngine.makeRequest(
  4771.             keyUris, this.config_.retryParameters);
  4772.         const keyResponse = this.makeNetworkRequest_(request, requestType);
  4773.         this.identityKeyMap_.set(keyMapKey, keyResponse);
  4774.       }
  4775.       const keyResponse = await this.identityKeyMap_.get(keyMapKey);
  4776.       key = shaka.util.Uint8ArrayUtils.toHex(keyResponse.data);
  4777.     }
  4779.     // NOTE: The ClearKey CDM requires a key-id to key mapping.  HLS doesn't
  4780.     // provide a key ID anywhere.  So although we could use the 'URI' attribute
  4781.     // to fetch the actual 16-byte key, without a key ID, we can't provide this
  4782.     // automatically to the ClearKey CDM. By default we assume that keyId is 0,
  4783.     // but we will try to get key ID from Init Segment.
  4784.     // If the application want override this behavior will have to use
  4785.     // player.configure('drm.clearKeys', { ... }) to provide the key IDs
  4786.     // and keys or player.configure('drm.servers.org\.w3\.clearkey', ...) to
  4787.     // provide a ClearKey license server URI.
  4788.     let keyId = '00000000000000000000000000000000';
  4790.     if (initSegmentRef) {
  4791.       let defaultKID;
  4792.       if (this.identityKidMap_.has(initSegmentRef)) {
  4793.         defaultKID = this.identityKidMap_.get(initSegmentRef);
  4794.       } else {
  4795.         const initSegmentRequest = shaka.util.Networking.createSegmentRequest(
  4796.             initSegmentRef.getUris(),
  4797.             initSegmentRef.getStartByte(),
  4798.             initSegmentRef.getEndByte(),
  4799.             this.config_.retryParameters);
  4800.         const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  4801.         const initType =
  4802.             shaka.net.NetworkingEngine.AdvancedRequestType.INIT_SEGMENT;
  4803.         const initResponse = await this.makeNetworkRequest_(
  4804.             initSegmentRequest, requestType, {type: initType});
  4806.         defaultKID = shaka.media.SegmentUtils.getDefaultKID(
  4807.             initResponse.data);
  4808.         this.identityKidMap_.set(initSegmentRef, defaultKID);
  4809.       }
  4810.       if (defaultKID) {
  4811.         keyId = defaultKID;
  4812.       }
  4813.     }
  4815.     const clearkeys = new Map();
  4816.     clearkeys.set(keyId, key);
  4818.     let encryptionScheme = 'cenc';
  4819.     if (method == 'SAMPLE-AES') {
  4820.       encryptionScheme = 'cbcs';
  4821.     }
  4823.     return shaka.util.ManifestParserUtils.createDrmInfoFromClearKeys(
  4824.         clearkeys, encryptionScheme);
  4825.   }
  4826. };
  4829. /**
  4830.  * @typedef {{
  4831.  *   stream: !shaka.extern.Stream,
  4832.  *   type: string,
  4833.  *   redirectUris: !Array.<string>,
  4834.  *   getUris: function():!Array.<string>,
  4835.  *   minTimestamp: number,
  4836.  *   maxTimestamp: number,
  4837.  *   mediaSequenceToStartTime: !Map.<number, number>,
  4838.  *   canSkipSegments: boolean,
  4839.  *   canBlockReload: boolean,
  4840.  *   hasEndList: boolean,
  4841.  *   firstSequenceNumber: number,
  4842.  *   nextMediaSequence: number,
  4843.  *   nextPart: number,
  4844.  *   loadedOnce: boolean
  4845.  * }}
  4846.  *
  4847.  * @description
  4848.  * Contains a stream and information about it.
  4849.  *
  4850.  * @property {!shaka.extern.Stream} stream
  4851.  *   The Stream itself.
  4852.  * @property {string} type
  4853.  *   The type value. Could be 'video', 'audio', 'text', or 'image'.
  4854.  * @property {!Array.<string>} redirectUris
  4855.  *   The redirect URIs.
  4856.  * @property {function():!Array.<string>} getUris
  4857.  *   The verbatim media playlist URIs, as it appeared in the master playlist.
  4858.  * @property {number} minTimestamp
  4859.  *   The minimum timestamp found in the stream.
  4860.  * @property {number} maxTimestamp
  4861.  *   The maximum timestamp found in the stream.
  4862.  * @property {!Map.<number, number>} mediaSequenceToStartTime
  4863.  *   A map of media sequence numbers to media start times.
  4864.  *   Only used for VOD content.
  4865.  * @property {boolean} canSkipSegments
  4866.  *   True if the server supports delta playlist updates, and we can send a
  4867.  *   request for a playlist that can skip older media segments.
  4868.  * @property {boolean} canBlockReload
  4869.  *   True if the server supports blocking playlist reload, and we can send a
  4870.  *   request for a playlist that can block reload until some segments are
  4871.  *   present.
  4872.  * @property {boolean} hasEndList
  4873.  *   True if the stream has an EXT-X-ENDLIST tag.
  4874.  * @property {number} firstSequenceNumber
  4875.  *   The sequence number of the first reference. Only calculated if needed.
  4876.  * @property {number} nextMediaSequence
  4877.  *   The next media sequence.
  4878.  * @property {number} nextPart
  4879.  *   The next part.
  4880.  * @property {boolean} loadedOnce
  4881.  *   True if the stream has been loaded at least once.
  4882.  */
  4883. shaka.hls.HlsParser.StreamInfo;
  4886. /**
  4887.  * @typedef {{
  4888.  *   audio: !Array.<shaka.hls.HlsParser.StreamInfo>,
  4889.  *   video: !Array.<shaka.hls.HlsParser.StreamInfo>
  4890.  * }}
  4891.  *
  4892.  * @description Audio and video stream infos.
  4893.  * @property {!Array.<shaka.hls.HlsParser.StreamInfo>} audio
  4894.  * @property {!Array.<shaka.hls.HlsParser.StreamInfo>} video
  4895.  */
  4896. shaka.hls.HlsParser.StreamInfos;
  4899. /**
  4900.  * @const {!Object.<string, string>}
  4901.  * @private
  4902.  */
  4903. shaka.hls.HlsParser.RAW_FORMATS_TO_MIME_TYPES_ = {
  4904.   'aac': 'audio/aac',
  4905.   'ac3': 'audio/ac3',
  4906.   'ec3': 'audio/ec3',
  4907.   'mp3': 'audio/mpeg',
  4908. };
  4911. /**
  4912.  * @const {!Object.<string, string>}
  4913.  * @private
  4914.  */
  4915. shaka.hls.HlsParser.AUDIO_EXTENSIONS_TO_MIME_TYPES_ = {
  4916.   'mp4': 'audio/mp4',
  4917.   'mp4a': 'audio/mp4',
  4918.   'm4s': 'audio/mp4',
  4919.   'm4i': 'audio/mp4',
  4920.   'm4a': 'audio/mp4',
  4921.   'm4f': 'audio/mp4',
  4922.   'cmfa': 'audio/mp4',
  4923.   // MPEG2-TS also uses video/ for audio: https://bit.ly/TsMse
  4924.   'ts': 'video/mp2t',
  4925.   'tsa': 'video/mp2t',
  4926. };
  4929. /**
  4930.  * @const {!Object.<string, string>}
  4931.  * @private
  4932.  */
  4933. shaka.hls.HlsParser.VIDEO_EXTENSIONS_TO_MIME_TYPES_ = {
  4934.   'mp4': 'video/mp4',
  4935.   'mp4v': 'video/mp4',
  4936.   'm4s': 'video/mp4',
  4937.   'm4i': 'video/mp4',
  4938.   'm4v': 'video/mp4',
  4939.   'm4f': 'video/mp4',
  4940.   'cmfv': 'video/mp4',
  4941.   'ts': 'video/mp2t',
  4942.   'tsv': 'video/mp2t',
  4943. };
  4946. /**
  4947.  * @const {!Object.<string, string>}
  4948.  * @private
  4949.  */
  4950. shaka.hls.HlsParser.TEXT_EXTENSIONS_TO_MIME_TYPES_ = {
  4951.   'mp4': 'application/mp4',
  4952.   'm4s': 'application/mp4',
  4953.   'm4i': 'application/mp4',
  4954.   'm4f': 'application/mp4',
  4955.   'cmft': 'application/mp4',
  4956.   'vtt': 'text/vtt',
  4957.   'webvtt': 'text/vtt',
  4958.   'ttml': 'application/ttml+xml',
  4959. };
  4962. /**
  4963.  * @const {!Object.<string, string>}
  4964.  * @private
  4965.  */
  4966. shaka.hls.HlsParser.IMAGE_EXTENSIONS_TO_MIME_TYPES_ = {
  4967.   'jpg': 'image/jpeg',
  4968.   'png': 'image/png',
  4969.   'svg': 'image/svg+xml',
  4970.   'webp': 'image/webp',
  4971.   'avif': 'image/avif',
  4972. };
  4975. /**
  4976.  * @const {!Object.<string, !Object.<string, string>>}
  4977.  * @private
  4978.  */
  4979. shaka.hls.HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_ = {
  4980.   'audio': shaka.hls.HlsParser.AUDIO_EXTENSIONS_TO_MIME_TYPES_,
  4981.   'video': shaka.hls.HlsParser.VIDEO_EXTENSIONS_TO_MIME_TYPES_,
  4982.   'text': shaka.hls.HlsParser.TEXT_EXTENSIONS_TO_MIME_TYPES_,
  4983.   'image': shaka.hls.HlsParser.IMAGE_EXTENSIONS_TO_MIME_TYPES_,
  4984. };
  4987. /**
  4988.  * MIME types without init segment.
  4989.  *
  4990.  * @const {!Set.<string>}
  4991.  * @private
  4992.  */
  4993. shaka.hls.HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_ = new Set([
  4994.   'video/mp2t',
  4995.   // Containerless types
  4996.   ...shaka.util.MimeUtils.RAW_FORMATS,
  4997. ]);
  5000. /**
  5001.  * @typedef {function(!shaka.hls.Tag, string):?shaka.extern.DrmInfo}
  5002.  * @private
  5003.  */
  5004. shaka.hls.HlsParser.DrmParser_;
  5007. /**
  5008.  * @const {!Object.<string, shaka.hls.HlsParser.DrmParser_>}
  5009.  * @private
  5010.  */
  5011. shaka.hls.HlsParser.KEYFORMATS_TO_DRM_PARSERS_ = {
  5012.   'com.apple.streamingkeydelivery':
  5013.       shaka.hls.HlsParser.fairplayDrmParser_,
  5014.   'urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed':
  5015.       shaka.hls.HlsParser.widevineDrmParser_,
  5016.   'com.microsoft.playready':
  5017.       shaka.hls.HlsParser.playreadyDrmParser_,
  5018. };
  5021. /**
  5022.  * @enum {string}
  5023.  * @private
  5024.  */
  5025. shaka.hls.HlsParser.PresentationType_ = {
  5026.   VOD: 'VOD',
  5027.   EVENT: 'EVENT',
  5028.   LIVE: 'LIVE',
  5029. };
  5031. shaka.media.ManifestParser.registerParserByMime(
  5032.     'application/x-mpegurl', () => new shaka.hls.HlsParser());
  5033. shaka.media.ManifestParser.registerParserByMime(
  5034.     'application/vnd.apple.mpegurl', () => new shaka.hls.HlsParser());