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.drm.DrmUtils');
  14. goog.require('shaka.drm.FairPlay');
  15. goog.require('shaka.drm.PlayReady');
  16. goog.require('shaka.hls.Attribute');
  17. goog.require('shaka.hls.ManifestTextParser');
  18. goog.require('shaka.hls.Playlist');
  19. goog.require('shaka.hls.PlaylistType');
  20. goog.require('shaka.hls.Tag');
  21. goog.require('shaka.hls.Utils');
  22. goog.require('shaka.log');
  23. goog.require('shaka.media.InitSegmentReference');
  24. goog.require('shaka.media.ManifestParser');
  25. goog.require('shaka.media.PresentationTimeline');
  26. goog.require('shaka.media.QualityObserver');
  27. goog.require('shaka.media.SegmentIndex');
  28. goog.require('shaka.media.SegmentReference');
  29. goog.require('shaka.media.SegmentUtils');
  30. goog.require('shaka.net.DataUriPlugin');
  31. goog.require('shaka.net.NetworkingEngine');
  32. goog.require('shaka.net.NetworkingEngine.PendingRequest');
  33. goog.require('shaka.util.ArrayUtils');
  34. goog.require('shaka.util.BufferUtils');
  35. goog.require('shaka.util.ContentSteeringManager');
  36. goog.require('shaka.util.Error');
  37. goog.require('shaka.util.EventManager');
  38. goog.require('shaka.util.FakeEvent');
  39. goog.require('shaka.util.LanguageUtils');
  40. goog.require('shaka.util.ManifestParserUtils');
  41. goog.require('shaka.util.MimeUtils');
  42. goog.require('shaka.util.Networking');
  43. goog.require('shaka.util.OperationManager');
  44. goog.require('shaka.util.Pssh');
  45. goog.require('shaka.util.Timer');
  46. goog.require('shaka.util.TsParser');
  47. goog.require('shaka.util.TXml');
  48. goog.require('shaka.util.StreamUtils');
  49. goog.require('shaka.util.Uint8ArrayUtils');
  50. goog.requireType('shaka.hls.Segment');
  53. /**
  54.  * HLS parser.
  55.  *
  56.  * @implements {shaka.extern.ManifestParser}
  57.  * @export
  58.  */
  59. shaka.hls.HlsParser = class {
  60.   /**
  61.    * Creates an Hls Parser object.
  62.    */
  63.   constructor() {
  64.     /** @private {?shaka.extern.ManifestParser.PlayerInterface} */
  65.     this.playerInterface_ = null;
  67.     /** @private {?shaka.extern.ManifestConfiguration} */
  68.     this.config_ = null;
  70.     /** @private {number} */
  71.     this.globalId_ = 1;
  73.     /** @private {!Map<string, string>} */
  74.     this.globalVariables_ = new Map();
  76.     /**
  77.      * A map from group id to stream infos created from the media tags.
  78.      * @private {!Map<string, !Array<?shaka.hls.HlsParser.StreamInfo>>}
  79.      */
  80.     this.groupIdToStreamInfosMap_ = new Map();
  82.     /**
  83.      * For media playlist lazy-loading to work in livestreams, we have to assume
  84.      * that each stream of a type (video, audio, etc) has the same mappings of
  85.      * sequence number to start time.
  86.      * This map stores those relationships.
  87.      * Only used during livestreams; we do not assume that VOD content is
  88.      * aligned in that way.
  89.      * @private {!Map<string, !Map<number, number>>}
  90.      */
  91.     this.mediaSequenceToStartTimeByType_ = new Map();
  93.     // Set initial maps.
  94.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  95.     this.mediaSequenceToStartTimeByType_.set(ContentType.VIDEO, new Map());
  96.     this.mediaSequenceToStartTimeByType_.set(ContentType.AUDIO, new Map());
  97.     this.mediaSequenceToStartTimeByType_.set(ContentType.TEXT, new Map());
  98.     this.mediaSequenceToStartTimeByType_.set(ContentType.IMAGE, new Map());
  100.     /** @private {!Map<string, shaka.hls.HlsParser.DrmParser_>} */
  101.     this.keyFormatsToDrmParsers_ = new Map()
  102.         .set('com.apple.streamingkeydelivery',
  103.             (tag, type, ref) => this.fairplayDrmParser_(tag, type, ref))
  104.         .set('urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed',
  105.             (tag, type, ref) => this.widevineDrmParser_(tag, type, ref))
  106.         .set('com.microsoft.playready',
  107.             (tag, type, ref) => this.playreadyDrmParser_(tag, type, ref))
  108.         .set('urn:uuid:3d5e6d35-9b9a-41e8-b843-dd3c6e72c42c',
  109.             (tag, type, ref) => this.wiseplayDrmParser_(tag, type, ref));
  111.     /**
  112.      * The values are strings of the form "<VIDEO URI> - <AUDIO URI>",
  113.      * where the URIs are the verbatim media playlist URIs as they appeared in
  114.      * the master playlist.
  115.      *
  116.      * Used to avoid duplicates that vary only in their text stream.
  117.      *
  118.      * @private {!Set<string>}
  119.      */
  120.     this.variantUriSet_ = new Set();
  122.     /**
  123.      * A map from (verbatim) media playlist URI to stream infos representing the
  124.      * playlists.
  125.      *
  126.      * On update, used to iterate through and update from media playlists.
  127.      *
  128.      * On initial parse, used to iterate through and determine minimum
  129.      * timestamps, offsets, and to handle TS rollover.
  130.      *
  131.      * During parsing, used to avoid duplicates in the async methods
  132.      * createStreamInfoFromMediaTags_, createStreamInfoFromImageTag_ and
  133.      * createStreamInfoFromVariantTags_.
  134.      *
  135.      * @private {!Map<string, shaka.hls.HlsParser.StreamInfo>}
  136.      */
  137.     this.uriToStreamInfosMap_ = new Map();
  139.     /** @private {?shaka.media.PresentationTimeline} */
  140.     this.presentationTimeline_ = null;
  142.     /**
  143.      * The master playlist URI, after redirects.
  144.      *
  145.      * @private {string}
  146.      */
  147.     this.masterPlaylistUri_ = '';
  149.     /** @private {shaka.hls.ManifestTextParser} */
  150.     this.manifestTextParser_ = new shaka.hls.ManifestTextParser();
  152.     /**
  153.      * The minimum sequence number for generated segments, when ignoring
  154.      * EXT-X-PROGRAM-DATE-TIME.
  155.      *
  156.      * @private {number}
  157.      */
  158.     this.minSequenceNumber_ = -1;
  160.     /**
  161.      * The lowest time value for any of the streams, as defined by the
  162.      * EXT-X-PROGRAM-DATE-TIME value. Measured in seconds since January 1, 1970.
  163.      *
  164.      * @private {number}
  165.      */
  166.     this.lowestSyncTime_ = Infinity;
  168.     /**
  169.      * Flag to indicate if any of the media playlists use
  170.      * EXT-X-PROGRAM-DATE-TIME.
  171.      *
  172.      * @private {boolean}
  173.      */
  174.     this.usesProgramDateTime_ = false;
  176.     /**
  177.      * Whether the streams have previously been "finalized"; that is to say,
  178.      * whether we have loaded enough streams to know information about the asset
  179.      * such as timing information, live status, etc.
  180.      *
  181.      * @private {boolean}
  182.      */
  183.     this.streamsFinalized_ = false;
  185.     /**
  186.      * Whether the manifest informs about the codec to use.
  187.      *
  188.      * @private
  189.      */
  190.     this.codecInfoInManifest_ = false;
  192.     /**
  193.      * This timer is used to trigger the start of a manifest update. A manifest
  194.      * update is async. Once the update is finished, the timer will be restarted
  195.      * to trigger the next update. The timer will only be started if the content
  196.      * is live content.
  197.      *
  198.      * @private {shaka.util.Timer}
  199.      */
  200.     this.updatePlaylistTimer_ = new shaka.util.Timer(() => {
  201.       if (this.mediaElement_ && !this.config_.continueLoadingWhenPaused) {
  202.         this.eventManager_.unlisten(this.mediaElement_, 'timeupdate');
  203.         if (this.mediaElement_.paused) {
  204.           this.eventManager_.listenOnce(
  205.               this.mediaElement_, 'timeupdate', () => this.onUpdate_());
  206.           return;
  207.         }
  208.       }
  209.       this.onUpdate_();
  210.     });
  212.     /** @private {shaka.hls.HlsParser.PresentationType_} */
  213.     this.presentationType_ = shaka.hls.HlsParser.PresentationType_.VOD;
  215.     /** @private {?shaka.extern.Manifest} */
  216.     this.manifest_ = null;
  218.     /** @private {number} */
  219.     this.maxTargetDuration_ = 0;
  221.     /** @private {number} */
  222.     this.lastTargetDuration_ = Infinity;
  224.     /**
  225.      * Partial segments target duration.
  226.      * @private {number}
  227.      */
  228.     this.partialTargetDuration_ = 0;
  230.     /** @private {number} */
  231.     this.presentationDelay_ = 0;
  233.     /** @private {number} */
  234.     this.lowLatencyPresentationDelay_ = 0;
  236.     /** @private {shaka.util.OperationManager} */
  237.     this.operationManager_ = new shaka.util.OperationManager();
  239.     /**
  240.      * A map from closed captions' group id, to a map of closed captions info.
  241.      * {group id -> {closed captions channel id -> language}}
  242.      * @private {Map<string, Map<string, string>>}
  243.      */
  244.     this.groupIdToClosedCaptionsMap_ = new Map();
  246.     /** @private {Map<string, string>} */
  247.     this.groupIdToCodecsMap_ = new Map();
  249.     /**
  250.      * A cache mapping EXT-X-MAP tag info to the InitSegmentReference created
  251.      * from the tag.
  252.      * The key is a string combining the EXT-X-MAP tag's absolute uri, and
  253.      * its BYTERANGE if available.
  254.      * @private {!Map<string, !shaka.media.InitSegmentReference>}
  255.      */
  256.     this.mapTagToInitSegmentRefMap_ = new Map();
  258.     /** @private {Map<string, !shaka.extern.aesKey>} */
  259.     this.aesKeyInfoMap_ = new Map();
  261.     /** @private {Map<string, !Promise<shaka.extern.Response>>} */
  262.     this.aesKeyMap_ = new Map();
  264.     /** @private {Map<string, !Promise<shaka.extern.Response>>} */
  265.     this.identityKeyMap_ = new Map();
  267.     /** @private {Map<!shaka.media.InitSegmentReference, ?string>} */
  268.     this.initSegmentToKidMap_ = new Map();
  270.     /** @private {boolean} */
  271.     this.lowLatencyMode_ = false;
  273.     /** @private {boolean} */
  274.     this.lowLatencyByterangeOptimization_ = false;
  276.     /**
  277.      * An ewma that tracks how long updates take.
  278.      * This is to mitigate issues caused by slow parsing on embedded devices.
  279.      * @private {!shaka.abr.Ewma}
  280.      */
  281.     this.averageUpdateDuration_ = new shaka.abr.Ewma(5);
  283.     /** @private {?shaka.util.ContentSteeringManager} */
  284.     this.contentSteeringManager_ = null;
  286.     /** @private {boolean} */
  287.     this.needsClosedCaptionsDetection_ = true;
  289.     /** @private {shaka.util.EventManager} */
  290.     this.eventManager_ = new shaka.util.EventManager();
  292.     /** @private {HTMLMediaElement} */
  293.     this.mediaElement_ = null;
  295.     /** @private {?number} */
  296.     this.startTime_ = null;
  298.     /** @private {function():boolean} */
  299.     this.isPreloadFn_ = () => false;
  300.   }
  303.   /**
  304.    * @param {shaka.extern.ManifestConfiguration} config
  305.    * @param {(function():boolean)=} isPreloadFn
  306.    * @override
  307.    * @exportInterface
  308.    */
  309.   configure(config, isPreloadFn) {
  310.     const needFireUpdate = this.playerInterface_ &&
  311.       config.updatePeriod != this.config_.updatePeriod &&
  312.       config.updatePeriod >= 0;
  313.     this.config_ = config;
  314.     if (isPreloadFn) {
  315.       this.isPreloadFn_ = isPreloadFn;
  316.     }
  318.     if (this.contentSteeringManager_) {
  319.       this.contentSteeringManager_.configure(this.config_);
  320.     }
  322.     if (needFireUpdate && this.manifest_ &&
  323.       this.manifest_.presentationTimeline.isLive()) {
  324.       this.updatePlaylistTimer_.tickNow();
  325.     }
  326.   }
  328.   /**
  329.    * @override
  330.    * @exportInterface
  331.    */
  332.   async start(uri, playerInterface) {
  333.     goog.asserts.assert(this.config_, 'Must call configure() before start()!');
  334.     this.playerInterface_ = playerInterface;
  335.     this.lowLatencyMode_ = playerInterface.isLowLatencyMode();
  337.     const response = await this.requestManifest_([uri]).promise;
  339.     // Record the master playlist URI after redirects.
  340.     this.masterPlaylistUri_ = response.uri;
  342.     goog.asserts.assert(response.data, 'Response data should be non-null!');
  343.     await this.parseManifest_(response.data);
  345.     goog.asserts.assert(this.manifest_, 'Manifest should be non-null');
  346.     return this.manifest_;
  347.   }
  349.   /**
  350.    * @override
  351.    * @exportInterface
  352.    */
  353.   stop() {
  354.     // Make sure we don't update the manifest again. Even if the timer is not
  355.     // running, this is safe to call.
  356.     if (this.updatePlaylistTimer_) {
  357.       this.updatePlaylistTimer_.stop();
  358.       this.updatePlaylistTimer_ = null;
  359.     }
  361.     /** @type {!Array<!Promise>} */
  362.     const pending = [];
  364.     if (this.operationManager_) {
  365.       pending.push(this.operationManager_.destroy());
  366.       this.operationManager_ = null;
  367.     }
  369.     this.playerInterface_ = null;
  370.     this.config_ = null;
  371.     this.variantUriSet_.clear();
  372.     this.manifest_ = null;
  373.     this.uriToStreamInfosMap_.clear();
  374.     this.groupIdToStreamInfosMap_.clear();
  375.     this.groupIdToCodecsMap_.clear();
  376.     this.globalVariables_.clear();
  377.     this.mapTagToInitSegmentRefMap_.clear();
  378.     this.aesKeyInfoMap_.clear();
  379.     this.aesKeyMap_.clear();
  380.     this.identityKeyMap_.clear();
  381.     this.initSegmentToKidMap_.clear();
  383.     if (this.contentSteeringManager_) {
  384.       this.contentSteeringManager_.destroy();
  385.     }
  387.     if (this.eventManager_) {
  388.       this.eventManager_.release();
  389.       this.eventManager_ = null;
  390.     }
  392.     return Promise.all(pending);
  393.   }
  395.   /**
  396.    * @override
  397.    * @exportInterface
  398.    */
  399.   async update() {
  400.     if (!this.isLive_()) {
  401.       return;
  402.     }
  404.     /** @type {!Array<!Promise>} */
  405.     const updates = [];
  406.     const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  408.     // This is necessary to calculate correctly the update time.
  409.     this.lastTargetDuration_ = Infinity;
  410.     this.manifest_.gapCount = 0;
  412.     // Only update active streams.
  413.     const activeStreamInfos = streamInfos.filter((s) => s.stream.segmentIndex);
  414.     for (const streamInfo of activeStreamInfos) {
  415.       updates.push(this.updateStream_(streamInfo));
  416.     }
  417.     await Promise.all(updates);
  419.     // Now that streams have been updated, notify the presentation timeline.
  420.     this.notifySegmentsForStreams_(activeStreamInfos.map((s) => s.stream));
  422.     // If any hasEndList is false, the stream is still live.
  423.     const stillLive = activeStreamInfos.some((s) => s.hasEndList == false);
  424.     if (activeStreamInfos.length && !stillLive) {
  425.       // Convert the presentation to VOD and set the duration.
  426.       const PresentationType = shaka.hls.HlsParser.PresentationType_;
  427.       this.setPresentationType_(PresentationType.VOD);
  429.       // The duration is the minimum of the end times of all active streams.
  430.       // Non-active streams are not guaranteed to have useful maxTimestamp
  431.       // values, due to the lazy-loading system, so they are ignored.
  432.       const maxTimestamps = activeStreamInfos.map((s) => s.maxTimestamp);
  433.       // The duration is the minimum of the end times of all streams.
  434.       this.presentationTimeline_.setDuration(Math.min(...maxTimestamps));
  435.       this.playerInterface_.updateDuration();
  436.     }
  437.     if (stillLive) {
  438.       this.determineDuration_();
  439.     }
  440.     // Check if any playlist does not have the first reference (due to a
  441.     // problem in the live encoder for example), and disable the stream if
  442.     // necessary.
  443.     for (const streamInfo of activeStreamInfos) {
  444.       if (!streamInfo.stream.isAudioMuxedInVideo &&
  445.           streamInfo.stream.segmentIndex &&
  446.           !streamInfo.stream.segmentIndex.earliestReference()) {
  447.         this.playerInterface_.disableStream(streamInfo.stream);
  448.       }
  449.     }
  450.   }
  452.   /**
  453.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  454.    * @return {!Map<number, number>}
  455.    * @private
  456.    */
  457.   getMediaSequenceToStartTimeFor_(streamInfo) {
  458.     if (this.isLive_()) {
  459.       return this.mediaSequenceToStartTimeByType_.get(streamInfo.type);
  460.     } else {
  461.       return streamInfo.mediaSequenceToStartTime;
  462.     }
  463.   }
  465.   /**
  466.    * Updates a stream.
  467.    *
  468.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  469.    * @return {!Promise}
  470.    * @private
  471.    */
  472.   async updateStream_(streamInfo) {
  473.     if (streamInfo.stream.isAudioMuxedInVideo) {
  474.       return;
  475.     }
  476.     const manifestUris = [];
  477.     for (const uri of streamInfo.getUris()) {
  478.       const uriObj = new goog.Uri(uri);
  479.       const queryData = uriObj.getQueryData();
  480.       if (streamInfo.canBlockReload) {
  481.         if (streamInfo.nextMediaSequence >= 0) {
  482.           // Indicates that the server must hold the request until a Playlist
  483.           // contains a Media Segment with Media Sequence
  484.           queryData.add('_HLS_msn', String(streamInfo.nextMediaSequence));
  485.         }
  486.         if (streamInfo.nextPart >= 0) {
  487.           // Indicates, in combination with _HLS_msn, that the server must hold
  488.           // the request until a Playlist contains Partial Segment N of Media
  489.           // Sequence Number M or later.
  490.           queryData.add('_HLS_part', String(streamInfo.nextPart));
  491.         }
  492.       }
  493.       if (streamInfo.canSkipSegments) {
  494.         // Enable delta updates. This will replace older segments with
  495.         // 'EXT-X-SKIP' tag in the media playlist.
  496.         queryData.add('_HLS_skip', 'YES');
  497.       }
  498.       if (queryData.getCount()) {
  499.         uriObj.setQueryData(queryData.toDecodedString());
  500.       }
  501.       manifestUris.push(uriObj.toString());
  502.     }
  503.     let response;
  504.     try {
  505.       response = await this.requestManifest_(
  506.           manifestUris, /* isPlaylist= */ true).promise;
  507.     } catch (e) {
  508.       if (this.playerInterface_) {
  509.         this.playerInterface_.disableStream(streamInfo.stream);
  510.       }
  511.       throw e;
  512.     }
  513.     if (!streamInfo.stream.segmentIndex) {
  514.       // The stream was closed since the update was first requested.
  515.       return;
  516.     }
  518.     /** @type {shaka.hls.Playlist} */
  519.     const playlist = this.manifestTextParser_.parsePlaylist(response.data);
  521.     if (playlist.type != shaka.hls.PlaylistType.MEDIA) {
  522.       throw new shaka.util.Error(
  523.           shaka.util.Error.Severity.CRITICAL,
  524.           shaka.util.Error.Category.MANIFEST,
  525.           shaka.util.Error.Code.HLS_INVALID_PLAYLIST_HIERARCHY);
  526.     }
  528.     // Record the final URI after redirects.
  529.     const responseUri = response.uri;
  530.     if (responseUri != response.originalUri &&
  531.         !streamInfo.getUris().includes(responseUri)) {
  532.       streamInfo.redirectUris.push(responseUri);
  533.     }
  535.     /** @type {!Array<!shaka.hls.Tag>} */
  536.     const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  537.         'EXT-X-DEFINE');
  539.     const mediaVariables = this.parseMediaVariables_(
  540.         variablesTags, responseUri);
  542.     const stream = streamInfo.stream;
  544.     const mediaSequenceToStartTime =
  545.         this.getMediaSequenceToStartTimeFor_(streamInfo);
  546.     const {keyIds, drmInfos, encrypted, aesEncrypted} =
  547.         await this.parseDrmInfo_(playlist, stream.mimeType,
  548.             streamInfo.getUris, mediaVariables);
  550.     if (!stream.encrypted && encrypted && !aesEncrypted) {
  551.       stream.encrypted = true;
  552.     }
  554.     const keysAreEqual =
  555.       (a, b) => a.size === b.size && [...a].every((value) => b.has(value));
  557.     if (!keysAreEqual(stream.keyIds, keyIds)) {
  558.       stream.keyIds = keyIds;
  559.       stream.drmInfos = drmInfos;
  560.       this.playerInterface_.newDrmInfo(stream);
  561.     }
  563.     const {segments, bandwidth} = this.createSegments_(
  564.         playlist, mediaSequenceToStartTime, mediaVariables,
  565.         streamInfo.getUris, streamInfo.type);
  566.     if (bandwidth) {
  567.       stream.bandwidth = bandwidth;
  568.     }
  570.     const qualityInfo =
  571.         shaka.media.QualityObserver.createQualityInfo(stream);
  572.     for (const segment of segments) {
  573.       if (segment.initSegmentReference) {
  574.         segment.initSegmentReference.mediaQuality = qualityInfo;
  575.       }
  576.     }
  578.     stream.segmentIndex.mergeAndEvict(
  579.         segments, this.presentationTimeline_.getSegmentAvailabilityStart());
  580.     if (segments.length) {
  581.       const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  582.           playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  583.       const skipTag = shaka.hls.Utils.getFirstTagWithName(
  584.           playlist.tags, 'EXT-X-SKIP');
  585.       const skippedSegments =
  586.           skipTag ? Number(skipTag.getAttributeValue('SKIPPED-SEGMENTS')) : 0;
  587.       const {nextMediaSequence, nextPart} =
  588.           this.getNextMediaSequenceAndPart_(mediaSequenceNumber, segments);
  589.       streamInfo.nextMediaSequence = nextMediaSequence + skippedSegments;
  590.       streamInfo.nextPart = nextPart;
  591.       const playlistStartTime = mediaSequenceToStartTime.get(
  592.           mediaSequenceNumber);
  593.       stream.segmentIndex.evict(playlistStartTime);
  594.     }
  595.     const oldSegment = stream.segmentIndex.earliestReference();
  596.     if (oldSegment) {
  597.       streamInfo.minTimestamp = oldSegment.startTime;
  599.       const newestSegment = segments[segments.length - 1];
  600.       goog.asserts.assert(newestSegment, 'Should have segments!');
  602.       streamInfo.maxTimestamp = newestSegment.endTime;
  603.     }
  605.     // Once the last segment has been added to the playlist,
  606.     // #EXT-X-ENDLIST tag will be appended.
  607.     // If that happened, treat the rest of the EVENT presentation as VOD.
  608.     const endListTag =
  609.         shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-ENDLIST');
  611.     if (endListTag) {
  612.       // Flag this for later.  We don't convert the whole presentation into VOD
  613.       // until we've seen the ENDLIST tag for all active playlists.
  614.       streamInfo.hasEndList = true;
  615.     }
  617.     this.determineLastTargetDuration_(playlist);
  619.     this.processDateRangeTags_(
  620.         playlist.tags, stream.type, mediaVariables, streamInfo.getUris);
  621.   }
  624.   /**
  625.    * @override
  626.    * @exportInterface
  627.    */
  628.   onExpirationUpdated(sessionId, expiration) {
  629.     // No-op
  630.   }
  632.   /**
  633.    * @override
  634.    * @exportInterface
  635.    */
  636.   onInitialVariantChosen(variant) {
  637.     // No-op
  638.   }
  640.   /**
  641.    * @override
  642.    * @exportInterface
  643.    */
  644.   banLocation(uri) {
  645.     if (this.contentSteeringManager_) {
  646.       this.contentSteeringManager_.banLocation(uri);
  647.     }
  648.   }
  650.   /**
  651.    * @override
  652.    * @exportInterface
  653.    */
  654.   setMediaElement(mediaElement) {
  655.     this.mediaElement_ = mediaElement;
  656.   }
  658.   /**
  659.    * Align the streams by sequence number by dropping early segments.  Then
  660.    * offset the streams to begin at presentation time 0.
  661.    * @param {!Array<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  662.    * @param {boolean=} force
  663.    * @private
  664.    */
  665.   syncStreamsWithSequenceNumber_(streamInfos, force = false) {
  666.     // We assume that, when this is first called, we have enough info to
  667.     // determine how to use the program date times (e.g. we have both a video
  668.     // and an audio, and all other videos and audios match those).
  669.     // Thus, we only need to calculate this once.
  670.     const updateMinSequenceNumber = this.minSequenceNumber_ == -1;
  671.     // Sync using media sequence number.  Find the highest starting sequence
  672.     // number among all streams.  Later, we will drop any references to
  673.     // earlier segments in other streams, then offset everything back to 0.
  674.     for (const streamInfo of streamInfos) {
  675.       const segmentIndex = streamInfo.stream.segmentIndex;
  676.       goog.asserts.assert(segmentIndex,
  677.           'Only loaded streams should be synced');
  678.       const mediaSequenceToStartTime =
  679.           this.getMediaSequenceToStartTimeFor_(streamInfo);
  680.       const segment0 = segmentIndex.earliestReference();
  681.       if (segment0) {
  682.         // This looks inefficient, but iteration order is insertion order.
  683.         // So the very first entry should be the one we want.
  684.         // We assert that this holds true so that we are alerted by debug
  685.         // builds and tests if it changes.  We still do a loop, though, so
  686.         // that the code functions correctly in production no matter what.
  687.         if (goog.DEBUG) {
  688.           const firstSequenceStartTime =
  689.               mediaSequenceToStartTime.values().next().value;
  690.           if (firstSequenceStartTime != segment0.startTime) {
  691.             shaka.log.warning(
  692.                 'Sequence number map is not ordered as expected!');
  693.           }
  694.         }
  695.         for (const [sequence, start] of mediaSequenceToStartTime) {
  696.           if (start == segment0.startTime) {
  697.             if (updateMinSequenceNumber) {
  698.               this.minSequenceNumber_ = Math.max(
  699.                   this.minSequenceNumber_, sequence);
  700.             }
  701.             // Even if we already have decided on a value for
  702.             // |this.minSequenceNumber_|, we still need to determine the first
  703.             // sequence number for the stream, to offset it in the code below.
  704.             streamInfo.firstSequenceNumber = sequence;
  705.             break;
  706.           }
  707.         }
  708.       }
  709.     }
  711.     if (this.minSequenceNumber_ < 0) {
  712.       // Nothing to sync.
  713.       return;
  714.     }
  716.     shaka.log.debug('Syncing HLS streams against base sequence number:',
  717.         this.minSequenceNumber_);
  719.     for (const streamInfo of streamInfos) {
  720.       if (!this.ignoreManifestProgramDateTimeFor_(streamInfo.type) && !force) {
  721.         continue;
  722.       }
  723.       const segmentIndex = streamInfo.stream.segmentIndex;
  724.       if (segmentIndex) {
  725.         // Drop any earlier references.
  726.         const numSegmentsToDrop =
  727.             this.minSequenceNumber_ - streamInfo.firstSequenceNumber;
  728.         if (numSegmentsToDrop > 0) {
  729.           segmentIndex.dropFirstReferences(numSegmentsToDrop);
  731.           // Now adjust timestamps back to begin at 0.
  732.           const segmentN = segmentIndex.earliestReference();
  733.           if (segmentN) {
  734.             const streamOffset = -segmentN.startTime;
  735.             // Modify all SegmentReferences equally.
  736.             streamInfo.stream.segmentIndex.offset(streamOffset);
  737.             // Update other parts of streamInfo the same way.
  738.             this.offsetStreamInfo_(streamInfo, streamOffset);
  739.           }
  740.         }
  741.       }
  742.     }
  743.   }
  745.   /**
  746.    * Synchronize streams by the EXT-X-PROGRAM-DATE-TIME tags attached to their
  747.    * segments.  Also normalizes segment times so that the earliest segment in
  748.    * any stream is at time 0.
  749.    * @param {!Array<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  750.    * @private
  751.    */
  752.   syncStreamsWithProgramDateTime_(streamInfos) {
  753.     // We assume that, when this is first called, we have enough info to
  754.     // determine how to use the program date times (e.g. we have both a video
  755.     // and an audio, and all other videos and audios match those).
  756.     // Thus, we only need to calculate this once.
  757.     if (this.lowestSyncTime_ == Infinity) {
  758.       for (const streamInfo of streamInfos) {
  759.         const segmentIndex = streamInfo.stream.segmentIndex;
  760.         goog.asserts.assert(segmentIndex,
  761.             'Only loaded streams should be synced');
  762.         const segment0 = segmentIndex.earliestReference();
  763.         if (segment0 != null && segment0.syncTime != null) {
  764.           this.lowestSyncTime_ =
  765.               Math.min(this.lowestSyncTime_, segment0.syncTime);
  766.         }
  767.       }
  768.     }
  770.     const lowestSyncTime = this.lowestSyncTime_;
  771.     if (lowestSyncTime == Infinity) {
  772.       // Nothing to sync.
  773.       return;
  774.     }
  776.     shaka.log.debug('Syncing HLS streams against base time:', lowestSyncTime);
  778.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  779.       if (this.ignoreManifestProgramDateTimeFor_(streamInfo.type)) {
  780.         continue;
  781.       }
  782.       const segmentIndex = streamInfo.stream.segmentIndex;
  783.       if (segmentIndex != null) {
  784.         // A segment's startTime should be based on its syncTime vs the lowest
  785.         // syncTime across all streams.  The earliest segment sync time from
  786.         // any stream will become presentation time 0.  If two streams start
  787.         // e.g. 6 seconds apart in syncTime, then their first segments will
  788.         // also start 6 seconds apart in presentation time.
  790.         const segment0 = segmentIndex.earliestReference();
  791.         if (!segment0) {
  792.           continue;
  793.         }
  794.         if (segment0.syncTime == null) {
  795.           shaka.log.alwaysError('Missing EXT-X-PROGRAM-DATE-TIME for stream',
  796.               streamInfo.getUris(),
  797.               'Expect AV sync issues!');
  798.         } else {
  799.           // Stream metadata are offset by a fixed amount based on the
  800.           // first segment.
  801.           const segment0TargetTime = segment0.syncTime - lowestSyncTime;
  802.           const streamOffset = segment0TargetTime - segment0.startTime;
  803.           this.offsetStreamInfo_(streamInfo, streamOffset);
  805.           // This is computed across all segments separately to manage
  806.           // accumulated drift in durations.
  807.           for (const segment of segmentIndex) {
  808.             segment.syncAgainst(lowestSyncTime);
  809.           }
  810.         }
  811.       }
  812.     }
  813.   }
  815.   /**
  816.    * @param {!shaka.hls.HlsParser.StreamInfo} streamInfo
  817.    * @param {number} offset
  818.    * @private
  819.    */
  820.   offsetStreamInfo_(streamInfo, offset) {
  821.     // Due to float compute issue we can have some millisecond issue.
  822.     // We don't apply the offset if it's the case.
  823.     if (Math.abs(offset) < 0.001) {
  824.       return;
  825.     }
  826.     // Adjust our accounting of the minimum timestamp.
  827.     streamInfo.minTimestamp += offset;
  829.     // Adjust our accounting of the maximum timestamp.
  830.     streamInfo.maxTimestamp += offset;
  831.     goog.asserts.assert(streamInfo.maxTimestamp >= 0,
  832.         'Negative maxTimestamp after adjustment!');
  834.     // Update our map from sequence number to start time.
  835.     const mediaSequenceToStartTime =
  836.         this.getMediaSequenceToStartTimeFor_(streamInfo);
  837.     for (const [key, value] of mediaSequenceToStartTime) {
  838.       mediaSequenceToStartTime.set(key, value + offset);
  839.     }
  841.     shaka.log.debug('Offset', offset, 'applied to',
  842.         streamInfo.getUris());
  843.   }
  845.   /**
  846.    * Parses the manifest.
  847.    *
  848.    * @param {BufferSource} data
  849.    * @return {!Promise}
  850.    * @private
  851.    */
  852.   async parseManifest_(data) {
  853.     const Utils = shaka.hls.Utils;
  854.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  856.     goog.asserts.assert(this.masterPlaylistUri_,
  857.         'Master playlist URI must be set before calling parseManifest_!');
  859.     const playlist = this.manifestTextParser_.parsePlaylist(data);
  861.     /** @type {!Array<!shaka.hls.Tag>} */
  862.     const variablesTags = Utils.filterTagsByName(playlist.tags, 'EXT-X-DEFINE');
  864.     /** @type {!Array<!shaka.extern.Variant>} */
  865.     let variants = [];
  866.     /** @type {!Array<!shaka.extern.Stream>} */
  867.     let textStreams = [];
  868.     /** @type {!Array<!shaka.extern.Stream>} */
  869.     let imageStreams = [];
  871.     // This assert is our own sanity check.
  872.     goog.asserts.assert(this.presentationTimeline_ == null,
  873.         'Presentation timeline created early!');
  874.     // We don't know if the presentation is VOD or live until we parse at least
  875.     // one media playlist, so make a VOD-style presentation timeline for now
  876.     // and change the type later if we discover this is live.
  877.     // Since the player will load the first variant chosen early in the process,
  878.     // there isn't a window during playback where the live-ness is unknown.
  879.     this.presentationTimeline_ = new shaka.media.PresentationTimeline(
  880.         /* presentationStartTime= */ null, /* delay= */ 0);
  881.     this.presentationTimeline_.setStatic(true);
  883.     const getUris = () => {
  884.       return [this.masterPlaylistUri_];
  885.     };
  887.     /** @type {?string} */
  888.     let mediaPlaylistType = null;
  890.     /** @type {!Map<string, string>} */
  891.     let mediaVariables = new Map();
  893.     // Parsing a media playlist results in a single-variant stream.
  894.     if (playlist.type == shaka.hls.PlaylistType.MEDIA) {
  895.       this.needsClosedCaptionsDetection_ = false;
  897.       /** @type {!Array<!shaka.hls.Tag>} */
  898.       const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  899.           'EXT-X-DEFINE');
  901.       mediaVariables = this.parseMediaVariables_(
  902.           variablesTags, this.masterPlaylistUri_);
  904.       // By default we assume it is video, but in a later step the correct type
  905.       // is obtained.
  906.       mediaPlaylistType = ContentType.VIDEO;
  908.       // These values can be obtained later so these default values are good.
  909.       const codecs = '';
  910.       const languageValue = '';
  911.       const channelsCount = null;
  912.       const sampleRate = null;
  913.       const closedCaptions = new Map();
  914.       const spatialAudio = false;
  915.       const characteristics = null;
  916.       const forced = false; // Only relevant for text.
  917.       const primary = true; // This is the only stream!
  918.       const name = 'Media Playlist';
  920.       // Make the stream info, with those values.
  921.       const streamInfo = await this.convertParsedPlaylistIntoStreamInfo_(
  922.           this.globalId_++, mediaVariables, playlist, getUris, codecs,
  923.           mediaPlaylistType, languageValue, primary, name, channelsCount,
  924.           closedCaptions, characteristics, forced, sampleRate, spatialAudio);
  925.       this.uriToStreamInfosMap_.set(this.masterPlaylistUri_, streamInfo);
  928.       if (streamInfo.stream) {
  929.         const qualityInfo =
  930.             shaka.media.QualityObserver.createQualityInfo(streamInfo.stream);
  931.         streamInfo.stream.segmentIndex.forEachTopLevelReference(
  932.             (reference) => {
  933.               if (reference.initSegmentReference) {
  934.                 reference.initSegmentReference.mediaQuality = qualityInfo;
  935.               }
  936.             });
  937.       }
  939.       mediaPlaylistType = streamInfo.stream.type;
  941.       // Wrap the stream from that stream info with a variant.
  942.       let variantAllowed = true;
  943.       if (this.config_.disableAudio && streamInfo.type == 'audio') {
  944.         variantAllowed = false;
  945.       } else if (this.config_.disableVideo && streamInfo.type == 'video' &&
  946.           !streamInfo.stream.codecs.includes(',')) {
  947.         variantAllowed = false;
  948.       }
  949.       if (variantAllowed) {
  950.         variants.push({
  951.           id: 0,
  952.           language: this.getLanguage_(languageValue),
  953.           disabledUntilTime: 0,
  954.           primary: true,
  955.           audio: streamInfo.type == 'audio' ? streamInfo.stream : null,
  956.           video: streamInfo.type == 'video' ? streamInfo.stream : null,
  957.           bandwidth: streamInfo.stream.bandwidth || 0,
  958.           allowedByApplication: true,
  959.           allowedByKeySystem: true,
  960.           decodingInfos: [],
  961.         });
  962.       }
  963.     } else {
  964.       this.parseMasterVariables_(variablesTags);
  966.       /** @type {!Array<!shaka.hls.Tag>} */
  967.       const mediaTags = Utils.filterTagsByName(
  968.           playlist.tags, 'EXT-X-MEDIA');
  969.       /** @type {!Array<!shaka.hls.Tag>} */
  970.       const variantTags = Utils.filterTagsByName(
  971.           playlist.tags, 'EXT-X-STREAM-INF');
  972.       /** @type {!Array<!shaka.hls.Tag>} */
  973.       const imageTags = Utils.filterTagsByName(
  974.           playlist.tags, 'EXT-X-IMAGE-STREAM-INF');
  975.       /** @type {!Array<!shaka.hls.Tag>} */
  976.       const iFrameTags = Utils.filterTagsByName(
  977.           playlist.tags, 'EXT-X-I-FRAME-STREAM-INF');
  978.       /** @type {!Array<!shaka.hls.Tag>} */
  979.       const sessionKeyTags = Utils.filterTagsByName(
  980.           playlist.tags, 'EXT-X-SESSION-KEY');
  981.       /** @type {!Array<!shaka.hls.Tag>} */
  982.       const sessionDataTags = Utils.filterTagsByName(
  983.           playlist.tags, 'EXT-X-SESSION-DATA');
  984.       /** @type {!Array<!shaka.hls.Tag>} */
  985.       const contentSteeringTags = Utils.filterTagsByName(
  986.           playlist.tags, 'EXT-X-CONTENT-STEERING');
  988.       this.processSessionData_(sessionDataTags);
  989.       await this.processContentSteering_(contentSteeringTags);
  991.       if (!this.config_.ignoreSupplementalCodecs) {
  992.         // Duplicate variant tags with supplementalCodecs
  993.         const newVariantTags = [];
  994.         for (const tag of variantTags) {
  995.           const supplementalCodecsString =
  996.               tag.getAttributeValue('SUPPLEMENTAL-CODECS');
  997.           if (!supplementalCodecsString) {
  998.             continue;
  999.           }
  1000.           const supplementalCodecs = supplementalCodecsString.split(/\s*,\s*/)
  1001.               .map((codec) => {
  1002.                 return codec.split('/')[0];
  1003.               });
  1004.           const newAttributes = tag.attributes.map((attr) => {
  1005.             const name = attr.name;
  1006.             let value = attr.value;
  1007.             if (name == 'CODECS') {
  1008.               value = supplementalCodecs.join(',');
  1009.               const allCodecs = attr.value.split(',');
  1010.               if (allCodecs.length > 1) {
  1011.                 const audioCodec =
  1012.                     shaka.util.ManifestParserUtils.guessCodecsSafe(
  1013.                         shaka.util.ManifestParserUtils.ContentType.AUDIO,
  1014.                         allCodecs);
  1015.                 if (audioCodec) {
  1016.                   value += ',' + audioCodec;
  1017.                 }
  1018.               }
  1019.             }
  1020.             return new shaka.hls.Attribute(name, value);
  1021.           });
  1022.           newVariantTags.push(
  1023.               new shaka.hls.Tag(tag.id, tag.name, newAttributes, null));
  1024.         }
  1025.         variantTags.push(...newVariantTags);
  1027.         // Duplicate iFrame tags with supplementalCodecs
  1028.         const newIFrameTags = [];
  1029.         for (const tag of iFrameTags) {
  1030.           const supplementalCodecsString =
  1031.               tag.getAttributeValue('SUPPLEMENTAL-CODECS');
  1032.           if (!supplementalCodecsString) {
  1033.             continue;
  1034.           }
  1035.           const supplementalCodecs = supplementalCodecsString.split(/\s*,\s*/)
  1036.               .map((codec) => {
  1037.                 return codec.split('/')[0];
  1038.               });
  1039.           const newAttributes = tag.attributes.map((attr) => {
  1040.             const name = attr.name;
  1041.             let value = attr.value;
  1042.             if (name == 'CODECS') {
  1043.               value = supplementalCodecs.join(',');
  1044.             }
  1045.             return new shaka.hls.Attribute(name, value);
  1046.           });
  1047.           newIFrameTags.push(
  1048.               new shaka.hls.Tag(tag.id, tag.name, newAttributes, null));
  1049.         }
  1050.         iFrameTags.push(...newIFrameTags);
  1051.       }
  1053.       this.parseCodecs_(variantTags);
  1055.       this.parseClosedCaptions_(mediaTags);
  1056.       const iFrameStreams = this.parseIFrames_(iFrameTags);
  1057.       variants = await this.createVariantsForTags_(
  1058.           variantTags, sessionKeyTags, mediaTags, getUris,
  1059.           this.globalVariables_, iFrameStreams);
  1060.       textStreams = this.parseTexts_(mediaTags);
  1061.       imageStreams = await this.parseImages_(imageTags, iFrameTags);
  1062.     }
  1064.     // Make sure that the parser has not been destroyed.
  1065.     if (!this.playerInterface_) {
  1066.       throw new shaka.util.Error(
  1067.           shaka.util.Error.Severity.CRITICAL,
  1068.           shaka.util.Error.Category.PLAYER,
  1069.           shaka.util.Error.Code.OPERATION_ABORTED);
  1070.     }
  1072.     this.determineStartTime_(playlist);
  1074.     // Single-variant streams aren't lazy-loaded, so for them we already have
  1075.     // enough info here to determine the presentation type and duration.
  1076.     if (playlist.type == shaka.hls.PlaylistType.MEDIA) {
  1077.       if (this.isLive_()) {
  1078.         this.changePresentationTimelineToLive_(playlist);
  1079.         const delay = this.getUpdatePlaylistDelay_();
  1080.         this.updatePlaylistTimer_.tickAfter(/* seconds= */ delay);
  1081.       }
  1082.       const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  1083.       this.finalizeStreams_(streamInfos);
  1084.       this.determineDuration_();
  1086.       goog.asserts.assert(mediaPlaylistType,
  1087.           'mediaPlaylistType should be non-null');
  1088.       this.processDateRangeTags_(
  1089.           playlist.tags, mediaPlaylistType, mediaVariables, getUris);
  1090.     }
  1092.     this.manifest_ = {
  1093.       presentationTimeline: this.presentationTimeline_,
  1094.       variants,
  1095.       textStreams,
  1096.       imageStreams,
  1097.       offlineSessionIds: [],
  1098.       sequenceMode: this.config_.hls.sequenceMode,
  1099.       ignoreManifestTimestampsInSegmentsMode:
  1100.         this.config_.hls.ignoreManifestTimestampsInSegmentsMode,
  1101.       type: shaka.media.ManifestParser.HLS,
  1102.       serviceDescription: null,
  1103.       nextUrl: null,
  1104.       periodCount: 1,
  1105.       gapCount: 0,
  1106.       isLowLatency: false,
  1107.       startTime: this.startTime_,
  1108.     };
  1110.     // If there is no 'CODECS' attribute in the manifest and codec guessing is
  1111.     // disabled, we need to create the segment indexes now so that missing info
  1112.     // can be parsed from the media data and added to the stream objects.
  1113.     if (!this.codecInfoInManifest_ && this.config_.hls.disableCodecGuessing) {
  1114.       const createIndexes = [];
  1115.       for (const variant of this.manifest_.variants) {
  1116.         if (variant.audio && variant.audio.codecs === '') {
  1117.           createIndexes.push(variant.audio.createSegmentIndex());
  1118.         }
  1119.         if (variant.video && variant.video.codecs === '') {
  1120.           createIndexes.push(variant.video.createSegmentIndex());
  1121.         }
  1122.       }
  1124.       await Promise.all(createIndexes);
  1125.     }
  1127.     this.playerInterface_.makeTextStreamsForClosedCaptions(this.manifest_);
  1128.   }
  1130.   /**
  1131.    * @param {!Array<!shaka.media.SegmentReference>} segments
  1132.    * @return {!Promise<shaka.media.SegmentUtils.BasicInfo>}
  1133.    * @private
  1134.    */
  1135.   async getBasicInfoFromSegments_(segments) {
  1136.     const HlsParser = shaka.hls.HlsParser;
  1137.     const defaultBasicInfo = shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1138.         this.config_.hls.mediaPlaylistFullMimeType);
  1139.     if (!segments.length) {
  1140.       return defaultBasicInfo;
  1141.     }
  1142.     const {segment, segmentIndex} = this.getAvailableSegment_(segments);
  1143.     const segmentUris = segment.getUris();
  1144.     const segmentUri = segmentUris[0];
  1145.     const parsedUri = new goog.Uri(segmentUri);
  1146.     const extension = parsedUri.getPath().split('.').pop();
  1147.     const rawMimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_.get(extension);
  1148.     if (rawMimeType) {
  1149.       return shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1150.           rawMimeType);
  1151.     }
  1153.     const basicInfos = await Promise.all([
  1154.       this.getInfoFromSegment_(segment.initSegmentReference, 0),
  1155.       this.getInfoFromSegment_(segment, segmentIndex),
  1156.     ]);
  1157.     const contentMimeType = basicInfos[1].mimeType;
  1158.     const initData = basicInfos[0].data;
  1159.     const data = basicInfos[1].data;
  1161.     const validMp4Extensions = [
  1162.       'mp4',
  1163.       'mp4a',
  1164.       'm4s',
  1165.       'm4i',
  1166.       'm4a',
  1167.       'm4f',
  1168.       'cmfa',
  1169.       'mp4v',
  1170.       'm4v',
  1171.       'cmfv',
  1172.       'fmp4',
  1173.     ];
  1174.     const validMp4MimeType = [
  1175.       'audio/mp4',
  1176.       'video/mp4',
  1177.       'video/iso.segment',
  1178.     ];
  1180.     // The extension isn't always a good indicator that it's MP4, so we don't
  1181.     // take it into account during the first validation.
  1182.     const isMp4 = segment.initSegmentReference ||
  1183.         validMp4MimeType.includes(contentMimeType);
  1185.     if (!isMp4 && shaka.util.TsParser.probe(
  1186.         shaka.util.BufferUtils.toUint8(data))) {
  1187.       const basicInfo = shaka.media.SegmentUtils.getBasicInfoFromTs(
  1188.           data, this.config_.disableAudio, this.config_.disableVideo,
  1189.           this.config_.disableText);
  1190.       if (basicInfo) {
  1191.         return basicInfo;
  1192.       }
  1193.     } else if (isMp4 || validMp4Extensions.includes(extension)) {
  1194.       const basicInfo = shaka.media.SegmentUtils.getBasicInfoFromMp4(
  1195.           initData, data, this.config_.disableText);
  1196.       if (basicInfo) {
  1197.         return basicInfo;
  1198.       }
  1199.     }
  1200.     if (contentMimeType) {
  1201.       return shaka.media.SegmentUtils.getBasicInfoFromMimeType(
  1202.           contentMimeType);
  1203.     }
  1204.     return defaultBasicInfo;
  1205.   }
  1207.   /**
  1208.    * @param {?shaka.media.AnySegmentReference} segment
  1209.    * @param {number} segmentIndex
  1210.    * @return {!Promise<{mimeType: ?string, data: ?BufferSource}>}
  1211.    * @private
  1212.    */
  1213.   async getInfoFromSegment_(segment, segmentIndex) {
  1214.     if (!segment) {
  1215.       return {mimeType: null, data: null};
  1216.     }
  1217.     const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  1218.     const segmentRequest = shaka.util.Networking.createSegmentRequest(
  1219.         segment.getUris(), segment.getStartByte(), segment.getEndByte(),
  1220.         this.config_.retryParameters);
  1221.     const type = segment instanceof shaka.media.SegmentReference ?
  1222.       shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_SEGMENT :
  1223.       shaka.net.NetworkingEngine.AdvancedRequestType.INIT_SEGMENT;
  1224.     const response = await this.makeNetworkRequest_(
  1225.         segmentRequest, requestType, {type}).promise;
  1226.     let data = response.data;
  1227.     if (segment.aesKey) {
  1228.       data = await shaka.media.SegmentUtils.aesDecrypt(
  1229.           data, segment.aesKey, segmentIndex);
  1230.     }
  1231.     if (segment instanceof shaka.media.SegmentReference) {
  1232.       segment.setSegmentData(data, /* singleUse= */ true);
  1233.     } else {
  1234.       segment.setSegmentData(data);
  1235.     }
  1237.     let mimeType = response.headers['content-type'];
  1238.     if (mimeType) {
  1239.       // Split the MIME type in case the server sent additional parameters.
  1240.       mimeType = mimeType.split(';')[0].toLowerCase();
  1241.     }
  1242.     return {mimeType, data};
  1243.   }
  1245.   /** @private */
  1246.   determineDuration_() {
  1247.     goog.asserts.assert(this.presentationTimeline_,
  1248.         'Presentation timeline not created!');
  1250.     if (this.isLive_()) {
  1251.       // The spec says nothing much about seeking in live content, but Safari's
  1252.       // built-in HLS implementation does not allow it.  Therefore we will set
  1253.       // the availability window equal to the presentation delay.  The player
  1254.       // will be able to buffer ahead three segments, but the seek window will
  1255.       // be zero-sized.
  1256.       const PresentationType = shaka.hls.HlsParser.PresentationType_;
  1258.       if (this.presentationType_ == PresentationType.LIVE) {
  1259.         let segmentAvailabilityDuration = this.getLiveDuration_() || 0;
  1261.         // The app can override that with a longer duration, to allow seeking.
  1262.         if (!isNaN(this.config_.availabilityWindowOverride)) {
  1263.           segmentAvailabilityDuration = this.config_.availabilityWindowOverride;
  1264.         }
  1266.         this.presentationTimeline_.setSegmentAvailabilityDuration(
  1267.             segmentAvailabilityDuration);
  1268.       }
  1269.     } else {
  1270.       // Use the minimum duration as the presentation duration.
  1271.       this.presentationTimeline_.setDuration(this.getMinDuration_());
  1272.     }
  1274.     if (!this.presentationTimeline_.isStartTimeLocked()) {
  1275.       for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  1276.         if (!streamInfo.stream.segmentIndex) {
  1277.           continue; // Not active.
  1278.         }
  1279.         if (streamInfo.type != 'audio' && streamInfo.type != 'video') {
  1280.           continue;
  1281.         }
  1282.         const firstReference =
  1283.             streamInfo.stream.segmentIndex.earliestReference();
  1284.         if (firstReference && firstReference.syncTime) {
  1285.           const syncTime = firstReference.syncTime;
  1286.           this.presentationTimeline_.setInitialProgramDateTime(syncTime);
  1287.         }
  1288.       }
  1289.     }
  1291.     // This is the first point where we have a meaningful presentation start
  1292.     // time, and we need to tell PresentationTimeline that so that it can
  1293.     // maintain consistency from here on.
  1294.     this.presentationTimeline_.lockStartTime();
  1296.     // This asserts that the live edge is being calculated from segment times.
  1297.     // For VOD and event streams, this check should still pass.
  1298.     goog.asserts.assert(
  1299.         !this.presentationTimeline_.usingPresentationStartTime(),
  1300.         'We should not be using the presentation start time in HLS!');
  1301.   }
  1303.   /**
  1304.    * Get the variables of each variant tag, and store in a map.
  1305.    * @param {!Array<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1306.    * @private
  1307.    */
  1308.   parseMasterVariables_(tags) {
  1309.     const queryParams = new goog.Uri(this.masterPlaylistUri_).getQueryData();
  1310.     for (const variableTag of tags) {
  1311.       const name = variableTag.getAttributeValue('NAME');
  1312.       const value = variableTag.getAttributeValue('VALUE');
  1313.       const queryParam = variableTag.getAttributeValue('QUERYPARAM');
  1314.       if (name && value) {
  1315.         if (!this.globalVariables_.has(name)) {
  1316.           this.globalVariables_.set(name, value);
  1317.         }
  1318.       }
  1319.       if (queryParam) {
  1320.         const queryParamValue = queryParams.get(queryParam)[0];
  1321.         if (queryParamValue && !this.globalVariables_.has(queryParamValue)) {
  1322.           this.globalVariables_.set(queryParam, queryParamValue);
  1323.         }
  1324.       }
  1325.     }
  1326.   }
  1328.   /**
  1329.    * Get the variables of each variant tag, and store in a map.
  1330.    * @param {!Array<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1331.    * @param {string} uri Media playlist URI.
  1332.    * @return {!Map<string, string>}
  1333.    * @private
  1334.    */
  1335.   parseMediaVariables_(tags, uri) {
  1336.     const queryParams = new goog.Uri(uri).getQueryData();
  1337.     const mediaVariables = new Map();
  1338.     for (const variableTag of tags) {
  1339.       const name = variableTag.getAttributeValue('NAME');
  1340.       const value = variableTag.getAttributeValue('VALUE');
  1341.       const queryParam = variableTag.getAttributeValue('QUERYPARAM');
  1342.       const mediaImport = variableTag.getAttributeValue('IMPORT');
  1343.       if (name && value) {
  1344.         if (!mediaVariables.has(name)) {
  1345.           mediaVariables.set(name, value);
  1346.         }
  1347.       }
  1348.       if (queryParam) {
  1349.         const queryParamValue = queryParams.get(queryParam)[0];
  1350.         if (queryParamValue && !mediaVariables.has(queryParamValue)) {
  1351.           mediaVariables.set(queryParam, queryParamValue);
  1352.         }
  1353.       }
  1354.       if (mediaImport) {
  1355.         const globalValue = this.globalVariables_.get(mediaImport);
  1356.         if (globalValue) {
  1357.           mediaVariables.set(mediaImport, globalValue);
  1358.         }
  1359.       }
  1360.     }
  1361.     return mediaVariables;
  1362.   }
  1364.   /**
  1365.    * Get the codecs of each variant tag, and store in a map from
  1366.    * audio/video/subtitle group id to the codecs array list.
  1367.    * @param {!Array<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1368.    * @private
  1369.    */
  1370.   parseCodecs_(tags) {
  1371.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1373.     for (const variantTag of tags) {
  1374.       const audioGroupId = variantTag.getAttributeValue('AUDIO');
  1375.       const videoGroupId = variantTag.getAttributeValue('VIDEO');
  1376.       const subGroupId = variantTag.getAttributeValue('SUBTITLES');
  1377.       const allCodecs = this.getCodecsForVariantTag_(variantTag);
  1379.       if (subGroupId) {
  1380.         const textCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1381.             ContentType.TEXT, allCodecs);
  1382.         goog.asserts.assert(textCodecs != null, 'Text codecs should be valid.');
  1383.         this.groupIdToCodecsMap_.set(subGroupId, textCodecs);
  1384.         shaka.util.ArrayUtils.remove(allCodecs, textCodecs);
  1385.       }
  1386.       if (audioGroupId) {
  1387.         let codecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1388.             ContentType.AUDIO, allCodecs);
  1389.         if (!codecs) {
  1390.           codecs = this.config_.hls.defaultAudioCodec;
  1391.         }
  1392.         this.groupIdToCodecsMap_.set(audioGroupId, codecs);
  1393.       }
  1394.       if (videoGroupId) {
  1395.         let codecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1396.             ContentType.VIDEO, allCodecs);
  1397.         if (!codecs) {
  1398.           codecs = this.config_.hls.defaultVideoCodec;
  1399.         }
  1400.         this.groupIdToCodecsMap_.set(videoGroupId, codecs);
  1401.       }
  1402.     }
  1403.   }
  1405.   /**
  1406.    * Process EXT-X-SESSION-DATA tags.
  1407.    *
  1408.    * @param {!Array<!shaka.hls.Tag>} tags
  1409.    * @private
  1410.    */
  1411.   processSessionData_(tags) {
  1412.     for (const tag of tags) {
  1413.       const id = tag.getAttributeValue('DATA-ID');
  1414.       const uri = tag.getAttributeValue('URI');
  1415.       const language = tag.getAttributeValue('LANGUAGE');
  1416.       const value = tag.getAttributeValue('VALUE');
  1417.       const data = (new Map()).set('id', id);
  1418.       if (uri) {
  1419.         data.set('uri', shaka.hls.Utils.constructSegmentUris(
  1420.             [this.masterPlaylistUri_], uri, this.globalVariables_)[0]);
  1421.       }
  1422.       if (language) {
  1423.         data.set('language', language);
  1424.       }
  1425.       if (value) {
  1426.         data.set('value', value);
  1427.       }
  1428.       const event = new shaka.util.FakeEvent('sessiondata', data);
  1429.       if (this.playerInterface_) {
  1430.         this.playerInterface_.onEvent(event);
  1431.       }
  1432.     }
  1433.   }
  1435.   /**
  1436.    * Process EXT-X-CONTENT-STEERING tags.
  1437.    *
  1438.    * @param {!Array<!shaka.hls.Tag>} tags
  1439.    * @return {!Promise}
  1440.    * @private
  1441.    */
  1442.   async processContentSteering_(tags) {
  1443.     if (!this.playerInterface_ || !this.config_) {
  1444.       return;
  1445.     }
  1446.     let contentSteeringPromise;
  1447.     for (const tag of tags) {
  1448.       const defaultPathwayId = tag.getAttributeValue('PATHWAY-ID');
  1449.       const uri = tag.getAttributeValue('SERVER-URI');
  1450.       if (!defaultPathwayId || !uri) {
  1451.         continue;
  1452.       }
  1453.       this.contentSteeringManager_ =
  1454.             new shaka.util.ContentSteeringManager(this.playerInterface_);
  1455.       this.contentSteeringManager_.configure(this.config_);
  1456.       this.contentSteeringManager_.setBaseUris([this.masterPlaylistUri_]);
  1457.       this.contentSteeringManager_.setManifestType(
  1458.           shaka.media.ManifestParser.HLS);
  1459.       this.contentSteeringManager_.setDefaultPathwayId(defaultPathwayId);
  1460.       contentSteeringPromise =
  1461.           this.contentSteeringManager_.requestInfo(uri);
  1462.       break;
  1463.     }
  1464.     await contentSteeringPromise;
  1465.   }
  1467.   /**
  1468.    * Parse Subtitles and Closed Captions from 'EXT-X-MEDIA' tags.
  1469.    * Create text streams for Subtitles, but not Closed Captions.
  1470.    *
  1471.    * @param {!Array<!shaka.hls.Tag>} mediaTags Media tags from the playlist.
  1472.    * @return {!Array<!shaka.extern.Stream>}
  1473.    * @private
  1474.    */
  1475.   parseTexts_(mediaTags) {
  1476.     // Create text stream for each Subtitle media tag.
  1477.     const subtitleTags =
  1478.         shaka.hls.Utils.filterTagsByType(mediaTags, 'SUBTITLES');
  1479.     const textStreams = subtitleTags.map((tag) => {
  1480.       const disableText = this.config_.disableText;
  1481.       if (disableText) {
  1482.         return null;
  1483.       }
  1484.       try {
  1485.         return this.createStreamInfoFromMediaTags_([tag], new Map()).stream;
  1486.       } catch (e) {
  1487.         if (this.config_.hls.ignoreTextStreamFailures) {
  1488.           return null;
  1489.         }
  1490.         throw e;
  1491.       }
  1492.     });
  1494.     const type = shaka.util.ManifestParserUtils.ContentType.TEXT;
  1496.     // Set the codecs for text streams.
  1497.     for (const tag of subtitleTags) {
  1498.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  1499.       const codecs = this.groupIdToCodecsMap_.get(groupId);
  1500.       if (codecs) {
  1501.         const textStreamInfos = this.groupIdToStreamInfosMap_.get(groupId);
  1502.         if (textStreamInfos) {
  1503.           for (const textStreamInfo of textStreamInfos) {
  1504.             textStreamInfo.stream.codecs = codecs;
  1505.             textStreamInfo.stream.mimeType =
  1506.                 this.guessMimeTypeBeforeLoading_(type, codecs) ||
  1507.                 this.guessMimeTypeFallback_(type);
  1508.             this.setFullTypeForStream_(textStreamInfo.stream);
  1509.           }
  1510.         }
  1511.       }
  1512.     }
  1514.     // Do not create text streams for Closed captions.
  1515.     return textStreams.filter((s) => s);
  1516.   }
  1518.   /**
  1519.    * @param {!shaka.extern.Stream} stream
  1520.    * @private
  1521.    */
  1522.   setFullTypeForStream_(stream) {
  1523.     const combinations = new Set([shaka.util.MimeUtils.getFullType(
  1524.         stream.mimeType, stream.codecs)]);
  1525.     if (stream.segmentIndex) {
  1526.       stream.segmentIndex.forEachTopLevelReference((reference) => {
  1527.         if (reference.mimeType) {
  1528.           combinations.add(shaka.util.MimeUtils.getFullType(
  1529.               reference.mimeType, stream.codecs));
  1530.         }
  1531.       });
  1532.     }
  1533.     stream.fullMimeTypes = combinations;
  1534.   }
  1536.   /**
  1537.    * @param {!Array<!shaka.hls.Tag>} imageTags from the playlist.
  1538.    * @param {!Array<!shaka.hls.Tag>} iFrameTags from the playlist.
  1539.    * @return {!Promise<!Array<!shaka.extern.Stream>>}
  1540.    * @private
  1541.    */
  1542.   async parseImages_(imageTags, iFrameTags) {
  1543.     // Create image stream for each image tag.
  1544.     const imageStreamPromises = imageTags.map(async (tag) => {
  1545.       const disableThumbnails = this.config_.disableThumbnails;
  1546.       if (disableThumbnails) {
  1547.         return null;
  1548.       }
  1549.       try {
  1550.         const streamInfo = await this.createStreamInfoFromImageTag_(tag);
  1551.         return streamInfo.stream;
  1552.       } catch (e) {
  1553.         if (this.config_.hls.ignoreImageStreamFailures) {
  1554.           return null;
  1555.         }
  1556.         throw e;
  1557.       }
  1558.     }).concat(iFrameTags.map((tag) => {
  1559.       const disableThumbnails = this.config_.disableThumbnails;
  1560.       if (disableThumbnails) {
  1561.         return null;
  1562.       }
  1563.       try {
  1564.         const streamInfo = this.createStreamInfoFromIframeTag_(tag);
  1565.         const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1566.         if (streamInfo.stream.type !== ContentType.IMAGE) {
  1567.           return null;
  1568.         }
  1569.         return streamInfo.stream;
  1570.       } catch (e) {
  1571.         if (this.config_.hls.ignoreImageStreamFailures) {
  1572.           return null;
  1573.         }
  1574.         throw e;
  1575.       }
  1576.     }));
  1577.     const imageStreams = await Promise.all(imageStreamPromises);
  1578.     return imageStreams.filter((s) => s);
  1579.   }
  1581.   /**
  1582.    * @param {!Array<!shaka.hls.Tag>} mediaTags Media tags from the playlist.
  1583.    * @param {!Map<string, string>} groupIdPathwayIdMapping
  1584.    * @private
  1585.    */
  1586.   createStreamInfosFromMediaTags_(mediaTags, groupIdPathwayIdMapping) {
  1587.     // Filter out subtitles and media tags without uri (except audio).
  1588.     mediaTags = mediaTags.filter((tag) => {
  1589.       const uri = tag.getAttributeValue('URI') || '';
  1590.       const type = tag.getAttributeValue('TYPE');
  1591.       return type != 'SUBTITLES' && (uri != '' || type == 'AUDIO');
  1592.     });
  1594.     const groupedTags = {};
  1595.     for (const tag of mediaTags) {
  1596.       const key = tag.getTagKey(!this.contentSteeringManager_);
  1597.       if (!groupedTags[key]) {
  1598.         groupedTags[key] = [tag];
  1599.       } else {
  1600.         groupedTags[key].push(tag);
  1601.       }
  1602.     }
  1604.     for (const key in groupedTags) {
  1605.       // Create stream info for each audio / video media grouped tag.
  1606.       this.createStreamInfoFromMediaTags_(
  1607.           groupedTags[key], groupIdPathwayIdMapping, /* requireUri= */ false);
  1608.     }
  1609.   }
  1611.   /**
  1612.    * @param {!Array<!shaka.hls.Tag>} iFrameTags from the playlist.
  1613.    * @return {!Array<!shaka.extern.Stream>}
  1614.    * @private
  1615.    */
  1616.   parseIFrames_(iFrameTags) {
  1617.     // Create iFrame stream for each iFrame tag.
  1618.     const iFrameStreams = iFrameTags.map((tag) => {
  1619.       const streamInfo = this.createStreamInfoFromIframeTag_(tag);
  1620.       const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1621.       if (streamInfo.stream.type !== ContentType.VIDEO) {
  1622.         return null;
  1623.       }
  1624.       return streamInfo.stream;
  1625.     });
  1627.     // Filter mjpg iFrames
  1628.     return iFrameStreams.filter((s) => s);
  1629.   }
  1631.   /**
  1632.    * @param {!Array<!shaka.hls.Tag>} tags Variant tags from the playlist.
  1633.    * @param {!Array<!shaka.hls.Tag>} sessionKeyTags EXT-X-SESSION-KEY tags
  1634.    * from the playlist.
  1635.    * @param {!Array<!shaka.hls.Tag>} mediaTags EXT-X-MEDIA tags from the
  1636.    * playlist.
  1637.    * @param {function(): !Array<string>} getUris
  1638.    * @param {?Map<string, string>} variables
  1639.    * @param {!Array<!shaka.extern.Stream>} iFrameStreams
  1640.    * @return {!Promise<!Array<!shaka.extern.Variant>>}
  1641.    * @private
  1642.    */
  1643.   async createVariantsForTags_(tags, sessionKeyTags, mediaTags, getUris,
  1644.       variables, iFrameStreams) {
  1645.     // EXT-X-SESSION-KEY processing
  1646.     const drmInfos = [];
  1647.     const keyIds = new Set();
  1648.     if (!this.config_.ignoreDrmInfo && sessionKeyTags.length > 0) {
  1649.       for (const drmTag of sessionKeyTags) {
  1650.         const method = drmTag.getRequiredAttrValue('METHOD');
  1651.         // According to the HLS spec, KEYFORMAT is optional and implicitly
  1652.         // defaults to "identity".
  1653.         // https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-4.4.4.4
  1654.         const keyFormat =
  1655.             drmTag.getAttributeValue('KEYFORMAT') || 'identity';
  1656.         let drmInfo = null;
  1657.         if (method == 'NONE') {
  1658.           continue;
  1659.         } else if (this.isAesMethod_(method)) {
  1660.           const keyUris = shaka.hls.Utils.constructSegmentUris(
  1661.               getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  1662.           const keyMapKey = keyUris.sort().join('');
  1663.           if (!this.aesKeyMap_.has(keyMapKey)) {
  1664.             const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  1665.             const request = shaka.net.NetworkingEngine.makeRequest(
  1666.                 keyUris, this.config_.retryParameters);
  1667.             const keyResponse = this.makeNetworkRequest_(request, requestType)
  1668.                 .promise;
  1669.             this.aesKeyMap_.set(keyMapKey, keyResponse);
  1670.           }
  1671.           continue;
  1672.         } else if (keyFormat == 'identity') {
  1673.           // eslint-disable-next-line no-await-in-loop
  1674.           drmInfo = await this.identityDrmParser_(
  1675.               drmTag, /* mimeType= */ '', getUris,
  1676.               /* initSegmentRef= */ null, variables);
  1677.         } else {
  1678.           const drmParser =
  1679.               this.keyFormatsToDrmParsers_.get(keyFormat);
  1681.           drmInfo = drmParser ?
  1682.             // eslint-disable-next-line no-await-in-loop
  1683.             await drmParser(drmTag, /* mimeType= */ '',
  1684.                 /* initSegmentRef= */ null) : null;
  1685.         }
  1686.         if (drmInfo) {
  1687.           if (drmInfo.keyIds) {
  1688.             for (const keyId of drmInfo.keyIds) {
  1689.               keyIds.add(keyId);
  1690.             }
  1691.           }
  1692.           drmInfos.push(drmInfo);
  1693.         } else {
  1694.           shaka.log.warning('Unsupported HLS KEYFORMAT', keyFormat);
  1695.         }
  1696.       }
  1697.     }
  1699.     const groupedTags = {};
  1700.     for (const tag of tags) {
  1701.       const key = tag.getTagKey(!this.contentSteeringManager_);
  1702.       if (!groupedTags[key]) {
  1703.         groupedTags[key] = [tag];
  1704.       } else {
  1705.         groupedTags[key].push(tag);
  1706.       }
  1707.     }
  1709.     const allVariants = [];
  1710.     // Create variants for each group of variant tag.
  1711.     for (const key in groupedTags) {
  1712.       const tags = groupedTags[key];
  1713.       const firstTag = tags[0];
  1715.       const frameRate = firstTag.getAttributeValue('FRAME-RATE');
  1716.       const bandwidth =
  1717.           Number(firstTag.getAttributeValue('AVERAGE-BANDWIDTH')) ||
  1718.           Number(firstTag.getRequiredAttrValue('BANDWIDTH'));
  1720.       const resolution = firstTag.getAttributeValue('RESOLUTION');
  1721.       const [width, height] = resolution ? resolution.split('x') : [null, null];
  1723.       const videoRange = firstTag.getAttributeValue('VIDEO-RANGE');
  1725.       let videoLayout = firstTag.getAttributeValue('REQ-VIDEO-LAYOUT');
  1726.       if (videoLayout && videoLayout.includes(',')) {
  1727.         // If multiple video layout strings are present, pick the first valid
  1728.         // one.
  1729.         const layoutStrings = videoLayout.split(',').filter((layoutString) => {
  1730.           return layoutString == 'CH-STEREO' || layoutString == 'CH-MONO';
  1731.         });
  1732.         videoLayout = layoutStrings[0];
  1733.       }
  1734.       // According to the HLS spec:
  1735.       // By default a video variant is monoscopic, so an attribute
  1736.       // consisting entirely of REQ-VIDEO-LAYOUT="CH-MONO" is unnecessary
  1737.       // and SHOULD NOT be present.
  1738.       videoLayout = videoLayout || 'CH-MONO';
  1740.       const streamInfos = this.createStreamInfosForVariantTags_(tags,
  1741.           mediaTags, resolution, frameRate);
  1743.       goog.asserts.assert(streamInfos.audio.length ||
  1744.           streamInfos.video.length, 'We should have created a stream!');
  1746.       allVariants.push(...this.createVariants_(
  1747.           streamInfos.audio,
  1748.           streamInfos.video,
  1749.           bandwidth,
  1750.           width,
  1751.           height,
  1752.           frameRate,
  1753.           videoRange,
  1754.           videoLayout,
  1755.           drmInfos,
  1756.           keyIds,
  1757.           iFrameStreams));
  1758.     }
  1759.     return allVariants.filter((variant) => variant != null);
  1760.   }
  1762.   /**
  1763.    * Create audio and video streamInfos from an 'EXT-X-STREAM-INF' tag and its
  1764.    * related media tags.
  1765.    *
  1766.    * @param {!Array<!shaka.hls.Tag>} tags
  1767.    * @param {!Array<!shaka.hls.Tag>} mediaTags
  1768.    * @param {?string} resolution
  1769.    * @param {?string} frameRate
  1770.    * @return {!shaka.hls.HlsParser.StreamInfos}
  1771.    * @private
  1772.    */
  1773.   createStreamInfosForVariantTags_(tags, mediaTags, resolution, frameRate) {
  1774.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1776.     /** @type {shaka.hls.HlsParser.StreamInfos} */
  1777.     const res = {
  1778.       audio: [],
  1779.       video: [],
  1780.     };
  1781.     const groupIdPathwayIdMapping = new Map();
  1782.     const globalGroupIds = [];
  1783.     let isAudioGroup = false;
  1784.     let isVideoGroup = false;
  1785.     for (const tag of tags) {
  1786.       const audioGroupId = tag.getAttributeValue('AUDIO');
  1787.       const videoGroupId = tag.getAttributeValue('VIDEO');
  1788.       goog.asserts.assert(audioGroupId == null || videoGroupId == null,
  1789.           'Unexpected: both video and audio described by media tags!');
  1791.       const groupId = audioGroupId || videoGroupId;
  1792.       if (!groupId) {
  1793.         continue;
  1794.       }
  1795.       if (!globalGroupIds.includes(groupId)) {
  1796.         globalGroupIds.push(groupId);
  1797.       }
  1798.       const pathwayId = tag.getAttributeValue('PATHWAY-ID');
  1799.       if (pathwayId) {
  1800.         groupIdPathwayIdMapping.set(groupId, pathwayId);
  1801.       }
  1802.       if (audioGroupId) {
  1803.         isAudioGroup = true;
  1804.       } else if (videoGroupId) {
  1805.         isVideoGroup = true;
  1806.       }
  1807.       // Make an educated guess about the stream type.
  1808.       shaka.log.debug('Guessing stream type for', tag.toString());
  1809.     }
  1810.     if (globalGroupIds.length && mediaTags.length) {
  1811.       const mediaTagsForVariant = mediaTags.filter((tag) => {
  1812.         return globalGroupIds.includes(tag.getRequiredAttrValue('GROUP-ID'));
  1813.       });
  1814.       this.createStreamInfosFromMediaTags_(
  1815.           mediaTagsForVariant, groupIdPathwayIdMapping);
  1816.     }
  1817.     const globalGroupId = globalGroupIds.sort().join(',');
  1818.     const streamInfos =
  1819.         (globalGroupId && this.groupIdToStreamInfosMap_.has(globalGroupId)) ?
  1820.         this.groupIdToStreamInfosMap_.get(globalGroupId) : [];
  1821.     if (isAudioGroup) {
  1822.       res.audio.push(...streamInfos);
  1823.     } else if (isVideoGroup) {
  1824.       res.video.push(...streamInfos);
  1825.     }
  1827.     let type;
  1828.     let ignoreStream = false;
  1830.     // The Microsoft HLS manifest generators will make audio-only variants
  1831.     // that link to their URI both directly and through an audio tag.
  1832.     // In that case, ignore the local URI and use the version in the
  1833.     // AUDIO tag, so you inherit its language.
  1834.     // As an example, see the manifest linked in issue #860.
  1835.     const allStreamUris = tags.map((tag) => tag.getRequiredAttrValue('URI'));
  1836.     const hasSameUri = res.audio.find((audio) => {
  1837.       return audio && audio.getUris().find((uri) => {
  1838.         return allStreamUris.includes(uri);
  1839.       });
  1840.     });
  1842.     /** @type {!Array<string>} */
  1843.     let allCodecs = this.getCodecsForVariantTag_(tags[0]);
  1844.     const videoCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1845.         ContentType.VIDEO, allCodecs);
  1846.     const audioCodecs = shaka.util.ManifestParserUtils.guessCodecsSafe(
  1847.         ContentType.AUDIO, allCodecs);
  1849.     if (audioCodecs && !videoCodecs) {
  1850.       // There are no associated media tags, and there's only audio codec,
  1851.       // and no video codec, so it should be audio.
  1852.       type = ContentType.AUDIO;
  1853.       shaka.log.debug('Guessing audio-only.');
  1854.       ignoreStream = res.audio.length > 0;
  1855.     } else if (!res.audio.length && !res.video.length &&
  1856.         audioCodecs && videoCodecs) {
  1857.       // There are both audio and video codecs, so assume multiplexed content.
  1858.       // Note that the default used when CODECS is missing assumes multiple
  1859.       // (and therefore multiplexed).
  1860.       // Recombine the codec strings into one so that MediaSource isn't
  1861.       // lied to later. (That would trigger an error in Chrome.)
  1862.       shaka.log.debug('Guessing multiplexed audio+video.');
  1863.       type = ContentType.VIDEO;
  1864.       allCodecs = [[videoCodecs, audioCodecs].join(',')];
  1865.     } else if (res.audio.length && hasSameUri) {
  1866.       shaka.log.debug('Guessing audio-only.');
  1867.       type = ContentType.AUDIO;
  1868.       ignoreStream = true;
  1869.     } else if (res.video.length && !res.audio.length) {
  1870.       // There are associated video streams.  Assume this is audio.
  1871.       shaka.log.debug('Guessing audio-only.');
  1872.       type = ContentType.AUDIO;
  1873.     } else {
  1874.       shaka.log.debug('Guessing video-only.');
  1875.       type = ContentType.VIDEO;
  1876.     }
  1878.     if (!ignoreStream) {
  1879.       const streamInfo =
  1880.           this.createStreamInfoFromVariantTags_(tags, allCodecs, type);
  1881.       if (globalGroupId) {
  1882.         streamInfo.stream.groupId = globalGroupId;
  1883.       }
  1884.       res[streamInfo.stream.type] = [streamInfo];
  1885.     }
  1886.     return res;
  1887.   }
  1890.   /**
  1891.    * Get the codecs from the 'EXT-X-STREAM-INF' tag.
  1892.    *
  1893.    * @param {!shaka.hls.Tag} tag
  1894.    * @return {!Array<string>} codecs
  1895.    * @private
  1896.    */
  1897.   getCodecsForVariantTag_(tag) {
  1898.     let codecsString = tag.getAttributeValue('CODECS') || '';
  1900.     this.codecInfoInManifest_ = codecsString.length > 0;
  1902.     if (!this.codecInfoInManifest_ && !this.config_.hls.disableCodecGuessing) {
  1903.       // These are the default codecs to assume if none are specified.
  1904.       const defaultCodecsArray = [];
  1906.       if (!this.config_.disableVideo) {
  1907.         defaultCodecsArray.push(this.config_.hls.defaultVideoCodec);
  1908.       }
  1909.       if (!this.config_.disableAudio) {
  1910.         defaultCodecsArray.push(this.config_.hls.defaultAudioCodec);
  1911.       }
  1913.       codecsString = defaultCodecsArray.join(',');
  1914.     }
  1916.     // Strip out internal whitespace while splitting on commas:
  1917.     /** @type {!Array<string>} */
  1918.     const codecs = codecsString.split(/\s*,\s*/);
  1920.     return shaka.media.SegmentUtils.codecsFiltering(codecs);
  1921.   }
  1923.   /**
  1924.    * Get the channel count information for an HLS audio track.
  1925.    * CHANNELS specifies an ordered, "/" separated list of parameters.
  1926.    * If the type is audio, the first parameter will be a decimal integer
  1927.    * specifying the number of independent, simultaneous audio channels.
  1928.    * No other channels parameters are currently defined.
  1929.    *
  1930.    * @param {!shaka.hls.Tag} tag
  1931.    * @return {?number}
  1932.    * @private
  1933.    */
  1934.   getChannelsCount_(tag) {
  1935.     const channels = tag.getAttributeValue('CHANNELS');
  1936.     if (!channels) {
  1937.       return null;
  1938.     }
  1939.     const channelCountString = channels.split('/')[0];
  1940.     const count = parseInt(channelCountString, 10);
  1941.     return count;
  1942.   }
  1944.   /**
  1945.    * Get the sample rate information for an HLS audio track.
  1946.    *
  1947.    * @param {!shaka.hls.Tag} tag
  1948.    * @return {?number}
  1949.    * @private
  1950.    */
  1951.   getSampleRate_(tag) {
  1952.     const sampleRate = tag.getAttributeValue('SAMPLE-RATE');
  1953.     if (!sampleRate) {
  1954.       return null;
  1955.     }
  1956.     return parseInt(sampleRate, 10);
  1957.   }
  1959.   /**
  1960.    * Get the spatial audio information for an HLS audio track.
  1961.    * In HLS the channels field indicates the number of audio channels that the
  1962.    * stream has (eg: 2). In the case of Dolby Atmos (EAC-3), the complexity is
  1963.    * expressed with the number of channels followed by the word JOC
  1964.    * (eg: 16/JOC), so 16 would be the number of channels (eg: 7.3.6 layout),
  1965.    * and JOC indicates that the stream has spatial audio. For Dolby AC-4 ATMOS,
  1966.    * it's necessary search ATMOS word.
  1967.    * @see https://developer.apple.com/documentation/http-live-streaming/hls-authoring-specification-for-apple-devices-appendixes
  1968.    * @see https://ott.dolby.com/OnDelKits/AC-4/Dolby_AC-4_Online_Delivery_Kit_1.5/Documentation/Specs/AC4_HLS/help_files/topics/hls_playlist_c_codec_indication_ims.html
  1969.    *
  1970.    * @param {!shaka.hls.Tag} tag
  1971.    * @return {boolean}
  1972.    * @private
  1973.    */
  1974.   isSpatialAudio_(tag) {
  1975.     const channels = tag.getAttributeValue('CHANNELS');
  1976.     if (!channels) {
  1977.       return false;
  1978.     }
  1979.     const channelsParts = channels.split('/');
  1980.     if (channelsParts.length != 2) {
  1981.       return false;
  1982.     }
  1983.     return channelsParts[1] === 'JOC' || channelsParts[1].includes('ATMOS');
  1984.   }
  1986.   /**
  1987.    * Get the closed captions map information for the EXT-X-STREAM-INF tag, to
  1988.    * create the stream info.
  1989.    * @param {!shaka.hls.Tag} tag
  1990.    * @param {string} type
  1991.    * @return {Map<string, string>} closedCaptions
  1992.    * @private
  1993.    */
  1994.   getClosedCaptions_(tag, type) {
  1995.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  1996.     // The attribute of closed captions is optional, and the value may be
  1997.     // 'NONE'.
  1998.     const closedCaptionsAttr = tag.getAttributeValue('CLOSED-CAPTIONS');
  2000.     // EXT-X-STREAM-INF tags may have CLOSED-CAPTIONS attributes.
  2001.     // The value can be either a quoted-string or an enumerated-string with
  2002.     // the value NONE. If the value is a quoted-string, it MUST match the
  2003.     // value of the GROUP-ID attribute of an EXT-X-MEDIA tag elsewhere in the
  2004.     // Playlist whose TYPE attribute is CLOSED-CAPTIONS.
  2005.     if (type == ContentType.VIDEO ) {
  2006.       if (this.config_.disableText) {
  2007.         this.needsClosedCaptionsDetection_ = false;
  2008.         return null;
  2009.       }
  2010.       if (closedCaptionsAttr) {
  2011.         if (closedCaptionsAttr != 'NONE') {
  2012.           return this.groupIdToClosedCaptionsMap_.get(closedCaptionsAttr);
  2013.         }
  2014.         this.needsClosedCaptionsDetection_ = false;
  2015.       } else if (!closedCaptionsAttr && this.groupIdToClosedCaptionsMap_.size) {
  2016.         for (const key of this.groupIdToClosedCaptionsMap_.keys()) {
  2017.           return this.groupIdToClosedCaptionsMap_.get(key);
  2018.         }
  2019.       }
  2020.     }
  2021.     return null;
  2022.   }
  2024.   /**
  2025.    * Get the normalized language value.
  2026.    *
  2027.    * @param {?string} languageValue
  2028.    * @return {string}
  2029.    * @private
  2030.    */
  2031.   getLanguage_(languageValue) {
  2032.     const LanguageUtils = shaka.util.LanguageUtils;
  2033.     return LanguageUtils.normalize(languageValue || 'und');
  2034.   }
  2036.   /**
  2037.    * Get the type value.
  2038.    * Shaka recognizes the content types 'audio', 'video', 'text', and 'image'.
  2039.    * The HLS 'subtitles' type needs to be mapped to 'text'.
  2040.    * @param {!shaka.hls.Tag} tag
  2041.    * @return {string}
  2042.    * @private
  2043.    */
  2044.   getType_(tag) {
  2045.     let type = tag.getRequiredAttrValue('TYPE').toLowerCase();
  2046.     if (type == 'subtitles') {
  2047.       type = shaka.util.ManifestParserUtils.ContentType.TEXT;
  2048.     }
  2049.     return type;
  2050.   }
  2052.   /**
  2053.    * @param {!Array<shaka.hls.HlsParser.StreamInfo>} audioInfos
  2054.    * @param {!Array<shaka.hls.HlsParser.StreamInfo>} videoInfos
  2055.    * @param {number} bandwidth
  2056.    * @param {?string} width
  2057.    * @param {?string} height
  2058.    * @param {?string} frameRate
  2059.    * @param {?string} videoRange
  2060.    * @param {?string} videoLayout
  2061.    * @param {!Array<shaka.extern.DrmInfo>} drmInfos
  2062.    * @param {!Set<string>} keyIds
  2063.    * @param {!Array<!shaka.extern.Stream>} iFrameStreams
  2064.    * @return {!Array<!shaka.extern.Variant>}
  2065.    * @private
  2066.    */
  2067.   createVariants_(
  2068.       audioInfos, videoInfos, bandwidth, width, height, frameRate, videoRange,
  2069.       videoLayout, drmInfos, keyIds, iFrameStreams) {
  2070.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2071.     const DrmUtils = shaka.drm.DrmUtils;
  2073.     for (const info of videoInfos) {
  2074.       this.addVideoAttributes_(
  2075.           info.stream, width, height, frameRate, videoRange, videoLayout,
  2076.           /** colorGamut= */ null);
  2077.     }
  2079.     // In case of audio-only or video-only content or the audio/video is
  2080.     // disabled by the config, we create an array of one item containing
  2081.     // a null. This way, the double-loop works for all kinds of content.
  2082.     // NOTE: we currently don't have support for audio-only content.
  2083.     const disableAudio = this.config_.disableAudio;
  2084.     if (!audioInfos.length || disableAudio) {
  2085.       audioInfos = [null];
  2086.     }
  2087.     const disableVideo = this.config_.disableVideo;
  2088.     if (!videoInfos.length || disableVideo) {
  2089.       videoInfos = [null];
  2090.     }
  2092.     const variants = [];
  2093.     for (const audioInfo of audioInfos) {
  2094.       for (const videoInfo of videoInfos) {
  2095.         const audioStream = audioInfo ? audioInfo.stream : null;
  2096.         if (audioStream) {
  2097.           audioStream.drmInfos = drmInfos;
  2098.           audioStream.keyIds = keyIds;
  2099.         }
  2100.         const videoStream = videoInfo ? videoInfo.stream : null;
  2101.         if (videoStream) {
  2102.           videoStream.drmInfos = drmInfos;
  2103.           videoStream.keyIds = keyIds;
  2104.           if (!this.config_.disableIFrames) {
  2105.             shaka.util.StreamUtils.setBetterIFrameStream(
  2106.                 videoStream, iFrameStreams);
  2107.           }
  2108.         }
  2109.         if (videoStream && !audioStream) {
  2110.           videoStream.bandwidth = bandwidth;
  2111.         }
  2112.         if (!videoStream && audioStream) {
  2113.           audioStream.bandwidth = bandwidth;
  2114.         }
  2115.         const audioDrmInfos = audioInfo ? audioInfo.stream.drmInfos : null;
  2116.         const videoDrmInfos = videoInfo ? videoInfo.stream.drmInfos : null;
  2117.         const videoStreamUri =
  2118.             videoInfo ? videoInfo.getUris().sort().join(',') : '';
  2119.         const audioStreamUri =
  2120.             audioInfo ? audioInfo.getUris().sort().join(',') : '';
  2121.         const codecs = [];
  2122.         if (audioStream && audioStream.codecs) {
  2123.           codecs.push(audioStream.codecs);
  2124.         }
  2125.         if (videoStream && videoStream.codecs) {
  2126.           codecs.push(videoStream.codecs);
  2127.         }
  2128.         const variantUriKey = [
  2129.           videoStreamUri,
  2130.           audioStreamUri,
  2131.           codecs.sort(),
  2132.         ].join('-');
  2134.         if (audioStream && videoStream) {
  2135.           if (!DrmUtils.areDrmCompatible(audioDrmInfos, videoDrmInfos)) {
  2136.             shaka.log.warning(
  2137.                 'Incompatible DRM info in HLS variant.  Skipping.');
  2138.             continue;
  2139.           }
  2140.         }
  2142.         if (this.variantUriSet_.has(variantUriKey)) {
  2143.           // This happens when two variants only differ in their text streams.
  2144.           shaka.log.debug(
  2145.               'Skipping variant which only differs in text streams.');
  2146.           continue;
  2147.         }
  2149.         // Since both audio and video are of the same type, this assertion will
  2150.         // catch certain mistakes at runtime that the compiler would miss.
  2151.         goog.asserts.assert(!audioStream ||
  2152.             audioStream.type == ContentType.AUDIO, 'Audio parameter mismatch!');
  2153.         goog.asserts.assert(!videoStream ||
  2154.             videoStream.type == ContentType.VIDEO, 'Video parameter mismatch!');
  2156.         const variant = {
  2157.           id: this.globalId_++,
  2158.           language: audioStream ? audioStream.language : 'und',
  2159.           disabledUntilTime: 0,
  2160.           primary: (!!audioStream && audioStream.primary) ||
  2161.               (!!videoStream && videoStream.primary),
  2162.           audio: audioStream,
  2163.           video: videoStream,
  2164.           bandwidth,
  2165.           allowedByApplication: true,
  2166.           allowedByKeySystem: true,
  2167.           decodingInfos: [],
  2168.         };
  2170.         variants.push(variant);
  2171.         this.variantUriSet_.add(variantUriKey);
  2172.       }
  2173.     }
  2174.     return variants;
  2175.   }
  2177.   /**
  2178.    * Parses an array of EXT-X-MEDIA tags, then stores the values of all tags
  2179.    * with TYPE="CLOSED-CAPTIONS" into a map of group id to closed captions.
  2180.    *
  2181.    * @param {!Array<!shaka.hls.Tag>} mediaTags
  2182.    * @private
  2183.    */
  2184.   parseClosedCaptions_(mediaTags) {
  2185.     const closedCaptionsTags =
  2186.         shaka.hls.Utils.filterTagsByType(mediaTags, 'CLOSED-CAPTIONS');
  2187.     this.needsClosedCaptionsDetection_ = closedCaptionsTags.length == 0;
  2188.     for (const tag of closedCaptionsTags) {
  2189.       goog.asserts.assert(tag.name == 'EXT-X-MEDIA',
  2190.           'Should only be called on media tags!');
  2191.       const languageValue = tag.getAttributeValue('LANGUAGE');
  2192.       let language = this.getLanguage_(languageValue);
  2193.       if (!languageValue) {
  2194.         const nameValue = tag.getAttributeValue('NAME');
  2195.         if (nameValue) {
  2196.           language = nameValue;
  2197.         }
  2198.       }
  2200.       // The GROUP-ID value is a quoted-string that specifies the group to which
  2201.       // the Rendition belongs.
  2202.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  2204.       // The value of INSTREAM-ID is a quoted-string that specifies a Rendition
  2205.       // within the segments in the Media Playlist. This attribute is REQUIRED
  2206.       // if the TYPE attribute is CLOSED-CAPTIONS.
  2207.       // We need replace SERVICE string by our internal svc string.
  2208.       const instreamId = tag.getRequiredAttrValue('INSTREAM-ID')
  2209.           .replace('SERVICE', 'svc');
  2210.       if (!this.groupIdToClosedCaptionsMap_.get(groupId)) {
  2211.         this.groupIdToClosedCaptionsMap_.set(groupId, new Map());
  2212.       }
  2213.       this.groupIdToClosedCaptionsMap_.get(groupId).set(instreamId, language);
  2214.     }
  2215.   }
  2217.   /**
  2218.    * Parse EXT-X-MEDIA media tag into a Stream object.
  2219.    *
  2220.    * @param {!Array<!shaka.hls.Tag>} tags
  2221.    * @param {!Map<string, string>} groupIdPathwayIdMapping
  2222.    * @param {boolean=} requireUri
  2223.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2224.    * @private
  2225.    */
  2226.   createStreamInfoFromMediaTags_(tags, groupIdPathwayIdMapping,
  2227.       requireUri = true) {
  2228.     const verbatimMediaPlaylistUris = [];
  2229.     const globalGroupIds = [];
  2230.     const groupIdUriMapping = new Map();
  2231.     for (const tag of tags) {
  2232.       goog.asserts.assert(tag.name == 'EXT-X-MEDIA',
  2233.           'Should only be called on media tags!');
  2234.       const uri = requireUri ? tag.getRequiredAttrValue('URI') :
  2235.           (tag.getAttributeValue('URI') || shaka.hls.HlsParser.FAKE_MUXED_URL_);
  2236.       const groupId = tag.getRequiredAttrValue('GROUP-ID');
  2237.       verbatimMediaPlaylistUris.push(uri);
  2238.       globalGroupIds.push(groupId);
  2239.       groupIdUriMapping.set(groupId, uri);
  2240.     }
  2242.     const globalGroupId = globalGroupIds.sort().join(',');
  2243.     const firstTag = tags[0];
  2244.     let codecs = '';
  2245.     /** @type {string} */
  2246.     const type = this.getType_(firstTag);
  2247.     if (type == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  2248.       codecs = firstTag.getAttributeValue('CODECS') || '';
  2249.     } else {
  2250.       for (const groupId of globalGroupIds) {
  2251.         if (this.groupIdToCodecsMap_.has(groupId)) {
  2252.           codecs = this.groupIdToCodecsMap_.get(groupId);
  2253.           break;
  2254.         }
  2255.       }
  2256.     }
  2258.     // Check if the stream has already been created as part of another Variant
  2259.     // and return it if it has.
  2260.     const key = verbatimMediaPlaylistUris.sort().join(',');
  2261.     if (this.uriToStreamInfosMap_.has(key)) {
  2262.       return this.uriToStreamInfosMap_.get(key);
  2263.     }
  2264.     const streamId = this.globalId_++;
  2265.     if (this.contentSteeringManager_) {
  2266.       for (const [groupId, uri] of groupIdUriMapping) {
  2267.         const pathwayId = groupIdPathwayIdMapping.get(groupId);
  2268.         if (pathwayId) {
  2269.           this.contentSteeringManager_.addLocation(streamId, pathwayId, uri);
  2270.         }
  2271.       }
  2272.     }
  2274.     const language = firstTag.getAttributeValue('LANGUAGE');
  2275.     const name = firstTag.getAttributeValue('NAME');
  2277.     // NOTE: According to the HLS spec, "DEFAULT=YES" requires "AUTOSELECT=YES".
  2278.     // However, we don't bother to validate "AUTOSELECT", since we don't
  2279.     // actually use it in our streaming model, and we treat everything as
  2280.     // "AUTOSELECT=YES".  A value of "AUTOSELECT=NO" would imply that it may
  2281.     // only be selected explicitly by the user, and we don't have a way to
  2282.     // represent that in our model.
  2283.     const defaultAttrValue = firstTag.getAttributeValue('DEFAULT');
  2284.     const primary = defaultAttrValue == 'YES';
  2286.     const channelsCount =
  2287.         type == 'audio' ? this.getChannelsCount_(firstTag) : null;
  2288.     const spatialAudio =
  2289.         type == 'audio' ? this.isSpatialAudio_(firstTag) : false;
  2290.     const characteristics = firstTag.getAttributeValue('CHARACTERISTICS');
  2292.     const forcedAttrValue = firstTag.getAttributeValue('FORCED');
  2293.     const forced = forcedAttrValue == 'YES';
  2294.     const sampleRate = type == 'audio' ? this.getSampleRate_(firstTag) : null;
  2295.     // TODO: Should we take into account some of the currently ignored
  2296.     // attributes: INSTREAM-ID, Attribute descriptions: https://bit.ly/2lpjOhj
  2297.     const streamInfo = this.createStreamInfo_(
  2298.         streamId, verbatimMediaPlaylistUris, codecs, type, language,
  2299.         primary, name, channelsCount, /* closedCaptions= */ null,
  2300.         characteristics, forced, sampleRate, spatialAudio);
  2301.     if (streamInfo.stream) {
  2302.       streamInfo.stream.groupId = globalGroupId;
  2303.     }
  2304.     if (this.groupIdToStreamInfosMap_.has(globalGroupId)) {
  2305.       this.groupIdToStreamInfosMap_.get(globalGroupId).push(streamInfo);
  2306.     } else {
  2307.       this.groupIdToStreamInfosMap_.set(globalGroupId, [streamInfo]);
  2308.     }
  2310.     this.uriToStreamInfosMap_.set(key, streamInfo);
  2311.     return streamInfo;
  2312.   }
  2314.   /**
  2315.    * Parse EXT-X-IMAGE-STREAM-INF media tag into a Stream object.
  2316.    *
  2317.    * @param {shaka.hls.Tag} tag
  2318.    * @return {!Promise<!shaka.hls.HlsParser.StreamInfo>}
  2319.    * @private
  2320.    */
  2321.   async createStreamInfoFromImageTag_(tag) {
  2322.     goog.asserts.assert(tag.name == 'EXT-X-IMAGE-STREAM-INF',
  2323.         'Should only be called on image tags!');
  2324.     /** @type {string} */
  2325.     const type = shaka.util.ManifestParserUtils.ContentType.IMAGE;
  2327.     const verbatimImagePlaylistUri = tag.getRequiredAttrValue('URI');
  2328.     const codecs = tag.getAttributeValue('CODECS', 'jpeg') || '';
  2330.     // Check if the stream has already been created as part of another Variant
  2331.     // and return it if it has.
  2332.     if (this.uriToStreamInfosMap_.has(verbatimImagePlaylistUri)) {
  2333.       return this.uriToStreamInfosMap_.get(verbatimImagePlaylistUri);
  2334.     }
  2336.     const language = tag.getAttributeValue('LANGUAGE');
  2337.     const name = tag.getAttributeValue('NAME');
  2339.     const characteristics = tag.getAttributeValue('CHARACTERISTICS');
  2341.     const streamInfo = this.createStreamInfo_(
  2342.         this.globalId_++, [verbatimImagePlaylistUri], codecs, type, language,
  2343.         /* primary= */ false, name, /* channelsCount= */ null,
  2344.         /* closedCaptions= */ null, characteristics, /* forced= */ false,
  2345.         /* sampleRate= */ null, /* spatialAudio= */ false);
  2347.     // Parse misc attributes.
  2348.     const resolution = tag.getAttributeValue('RESOLUTION');
  2349.     if (resolution) {
  2350.       // The RESOLUTION tag represents the resolution of a single thumbnail, not
  2351.       // of the entire sheet at once (like we expect in the output).
  2352.       // So multiply by the layout size.
  2354.       // Since we need to have generated the segment index for this, we can't
  2355.       // lazy-load in this situation.
  2356.       await streamInfo.stream.createSegmentIndex();
  2358.       const reference = streamInfo.stream.segmentIndex.earliestReference();
  2359.       const layout = reference.getTilesLayout();
  2360.       if (layout) {
  2361.         streamInfo.stream.width =
  2362.             Number(resolution.split('x')[0]) * Number(layout.split('x')[0]);
  2363.         streamInfo.stream.height =
  2364.             Number(resolution.split('x')[1]) * Number(layout.split('x')[1]);
  2365.         // TODO: What happens if there are multiple grids, with different
  2366.         // layout sizes, inside this image stream?
  2367.       }
  2368.     }
  2369.     const bandwidth = tag.getAttributeValue('BANDWIDTH');
  2370.     if (bandwidth) {
  2371.       streamInfo.stream.bandwidth = Number(bandwidth);
  2372.     }
  2374.     this.uriToStreamInfosMap_.set(verbatimImagePlaylistUri, streamInfo);
  2375.     return streamInfo;
  2376.   }
  2378.   /**
  2379.    * Parse EXT-X-I-FRAME-STREAM-INF media tag into a Stream object.
  2380.    *
  2381.    * @param {shaka.hls.Tag} tag
  2382.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2383.    * @private
  2384.    */
  2385.   createStreamInfoFromIframeTag_(tag) {
  2386.     goog.asserts.assert(tag.name == 'EXT-X-I-FRAME-STREAM-INF',
  2387.         'Should only be called on iframe tags!');
  2388.     /** @type {string} */
  2389.     let type = shaka.util.ManifestParserUtils.ContentType.VIDEO;
  2391.     const verbatimIFramePlaylistUri = tag.getRequiredAttrValue('URI');
  2392.     const codecs = tag.getAttributeValue('CODECS') || '';
  2394.     if (codecs == 'mjpg') {
  2395.       type = shaka.util.ManifestParserUtils.ContentType.IMAGE;
  2396.     }
  2398.     // Check if the stream has already been created as part of another Variant
  2399.     // and return it if it has.
  2400.     if (this.uriToStreamInfosMap_.has(verbatimIFramePlaylistUri)) {
  2401.       return this.uriToStreamInfosMap_.get(verbatimIFramePlaylistUri);
  2402.     }
  2404.     const language = tag.getAttributeValue('LANGUAGE');
  2405.     const name = tag.getAttributeValue('NAME');
  2407.     const characteristics = tag.getAttributeValue('CHARACTERISTICS');
  2409.     const streamInfo = this.createStreamInfo_(
  2410.         this.globalId_++, [verbatimIFramePlaylistUri], codecs, type, language,
  2411.         /* primary= */ false, name, /* channelsCount= */ null,
  2412.         /* closedCaptions= */ null, characteristics, /* forced= */ false,
  2413.         /* sampleRate= */ null, /* spatialAudio= */ false);
  2415.     // Parse misc attributes.
  2416.     const resolution = tag.getAttributeValue('RESOLUTION');
  2417.     const [width, height] = resolution ? resolution.split('x') : [null, null];
  2418.     streamInfo.stream.width = Number(width) || undefined;
  2419.     streamInfo.stream.height = Number(height) || undefined;
  2420.     const bandwidth = tag.getAttributeValue('BANDWIDTH');
  2421.     if (bandwidth) {
  2422.       streamInfo.stream.bandwidth = Number(bandwidth);
  2423.     }
  2425.     this.uriToStreamInfosMap_.set(verbatimIFramePlaylistUri, streamInfo);
  2426.     return streamInfo;
  2427.   }
  2429.   /**
  2430.    * Parse an EXT-X-STREAM-INF media tag into a Stream object.
  2431.    *
  2432.    * @param {!Array<!shaka.hls.Tag>} tags
  2433.    * @param {!Array<string>} allCodecs
  2434.    * @param {string} type
  2435.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2436.    * @private
  2437.    */
  2438.   createStreamInfoFromVariantTags_(tags, allCodecs, type) {
  2439.     const streamId = this.globalId_++;
  2440.     const verbatimMediaPlaylistUris = [];
  2441.     for (const tag of tags) {
  2442.       goog.asserts.assert(tag.name == 'EXT-X-STREAM-INF',
  2443.           'Should only be called on variant tags!');
  2444.       const uri = tag.getRequiredAttrValue('URI');
  2445.       const pathwayId = tag.getAttributeValue('PATHWAY-ID');
  2446.       if (this.contentSteeringManager_ && pathwayId) {
  2447.         this.contentSteeringManager_.addLocation(streamId, pathwayId, uri);
  2448.       }
  2449.       verbatimMediaPlaylistUris.push(uri);
  2450.     }
  2452.     const key = verbatimMediaPlaylistUris.sort().join(',') +
  2453.         allCodecs.sort().join(',');
  2454.     if (this.uriToStreamInfosMap_.has(key)) {
  2455.       return this.uriToStreamInfosMap_.get(key);
  2456.     }
  2458.     const name = verbatimMediaPlaylistUris.join(',');
  2459.     const closedCaptions = this.getClosedCaptions_(tags[0], type);
  2460.     const codecs = shaka.util.ManifestParserUtils.guessCodecs(type, allCodecs);
  2461.     const streamInfo = this.createStreamInfo_(
  2462.         streamId, verbatimMediaPlaylistUris,
  2463.         codecs, type, /* language= */ null, /* primary= */ false,
  2464.         name, /* channelCount= */ null, closedCaptions,
  2465.         /* characteristics= */ null, /* forced= */ false,
  2466.         /* sampleRate= */ null, /* spatialAudio= */ false);
  2468.     this.uriToStreamInfosMap_.set(key, streamInfo);
  2469.     return streamInfo;
  2470.   }
  2473.   /**
  2474.    * @param {number} streamId
  2475.    * @param {!Array<string>} verbatimMediaPlaylistUris
  2476.    * @param {string} codecs
  2477.    * @param {string} type
  2478.    * @param {?string} languageValue
  2479.    * @param {boolean} primary
  2480.    * @param {?string} name
  2481.    * @param {?number} channelsCount
  2482.    * @param {Map<string, string>} closedCaptions
  2483.    * @param {?string} characteristics
  2484.    * @param {boolean} forced
  2485.    * @param {?number} sampleRate
  2486.    * @param {boolean} spatialAudio
  2487.    * @return {!shaka.hls.HlsParser.StreamInfo}
  2488.    * @private
  2489.    */
  2490.   createStreamInfo_(streamId, verbatimMediaPlaylistUris, codecs, type,
  2491.       languageValue, primary, name, channelsCount, closedCaptions,
  2492.       characteristics, forced, sampleRate, spatialAudio) {
  2493.     // TODO: Refactor, too many parameters
  2495.     // This stream is lazy-loaded inside the createSegmentIndex function.
  2496.     // So we start out with a stream object that does not contain the actual
  2497.     // segment index, then download when createSegmentIndex is called.
  2498.     const stream = this.makeStreamObject_(streamId, codecs, type,
  2499.         languageValue, primary, name, channelsCount, closedCaptions,
  2500.         characteristics, forced, sampleRate, spatialAudio);
  2502.     const FAKE_MUXED_URL_ = shaka.hls.HlsParser.FAKE_MUXED_URL_;
  2503.     if (verbatimMediaPlaylistUris.includes(FAKE_MUXED_URL_)) {
  2504.       stream.isAudioMuxedInVideo = true;
  2505.       // We assigned the TS mimetype because it is the only one that works
  2506.       // with this functionality. MP4 is not supported right now.
  2507.       stream.mimeType = 'video/mp2t';
  2508.       this.setFullTypeForStream_(stream);
  2509.     }
  2511.     const streamInfo = {
  2512.       stream,
  2513.       type,
  2514.       redirectUris: [],
  2515.       getUris: () => {},
  2516.       // These values are filled out or updated after lazy-loading:
  2517.       minTimestamp: 0,
  2518.       maxTimestamp: 0,
  2519.       mediaSequenceToStartTime: new Map(),
  2520.       canSkipSegments: false,
  2521.       canBlockReload: false,
  2522.       hasEndList: false,
  2523.       firstSequenceNumber: -1,
  2524.       nextMediaSequence: -1,
  2525.       nextPart: -1,
  2526.       loadedOnce: false,
  2527.     };
  2529.     const getUris = () => {
  2530.       if (this.contentSteeringManager_ &&
  2531.           verbatimMediaPlaylistUris.length > 1) {
  2532.         return this.contentSteeringManager_.getLocations(streamId);
  2533.       }
  2534.       return streamInfo.redirectUris.concat(shaka.hls.Utils.constructUris(
  2535.           [this.masterPlaylistUri_], verbatimMediaPlaylistUris,
  2536.           this.globalVariables_));
  2537.     };
  2539.     streamInfo.getUris = getUris;
  2541.     /** @param {!shaka.net.NetworkingEngine.PendingRequest} pendingRequest */
  2542.     const downloadSegmentIndex = async (pendingRequest) => {
  2543.       const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2545.       try {
  2546.         // Download the actual manifest.
  2547.         const response = await pendingRequest.promise;
  2548.         if (pendingRequest.aborted) {
  2549.           return;
  2550.         }
  2552.         // Record the final URI after redirects.
  2553.         const responseUri = response.uri;
  2554.         if (responseUri != response.originalUri) {
  2555.           const uris = streamInfo.getUris();
  2556.           if (!uris.includes(responseUri)) {
  2557.             streamInfo.redirectUris.push(responseUri);
  2558.           }
  2559.         }
  2561.         // Record the redirected, final URI of this media playlist when we parse
  2562.         // it.
  2563.         /** @type {!shaka.hls.Playlist} */
  2564.         const playlist = this.manifestTextParser_.parsePlaylist(response.data);
  2566.         if (playlist.type != shaka.hls.PlaylistType.MEDIA) {
  2567.           throw new shaka.util.Error(
  2568.               shaka.util.Error.Severity.CRITICAL,
  2569.               shaka.util.Error.Category.MANIFEST,
  2570.               shaka.util.Error.Code.HLS_INVALID_PLAYLIST_HIERARCHY);
  2571.         }
  2573.         /** @type {!Array<!shaka.hls.Tag>} */
  2574.         const variablesTags = shaka.hls.Utils.filterTagsByName(playlist.tags,
  2575.             'EXT-X-DEFINE');
  2577.         const mediaVariables =
  2578.             this.parseMediaVariables_(variablesTags, responseUri);
  2580.         const mimeType = undefined;
  2582.         let requestBasicInfo = false;
  2584.         // If no codec info was provided in the manifest and codec guessing is
  2585.         // disabled we try to get necessary info from the media data.
  2586.         if ((!this.codecInfoInManifest_ &&
  2587.             this.config_.hls.disableCodecGuessing) ||
  2588.             (this.needsClosedCaptionsDetection_ && type == ContentType.VIDEO &&
  2589.             !this.config_.hls.disableClosedCaptionsDetection)) {
  2590.           if (playlist.segments.length > 0) {
  2591.             this.needsClosedCaptionsDetection_ = false;
  2592.             requestBasicInfo = true;
  2593.           }
  2594.         }
  2596.         const allowOverrideMimeType = !this.codecInfoInManifest_ &&
  2597.           this.config_.hls.disableCodecGuessing;
  2599.         const wasLive = this.isLive_();
  2600.         const realStreamInfo = await this.convertParsedPlaylistIntoStreamInfo_(
  2601.             streamId, mediaVariables, playlist, getUris, codecs,
  2602.             type, languageValue, primary, name, channelsCount, closedCaptions,
  2603.             characteristics, forced, sampleRate, spatialAudio, mimeType,
  2604.             requestBasicInfo, allowOverrideMimeType);
  2605.         if (pendingRequest.aborted) {
  2606.           return;
  2607.         }
  2609.         const realStream = realStreamInfo.stream;
  2611.         this.determineStartTime_(playlist);
  2613.         if (this.isLive_() && !wasLive) {
  2614.           // Now that we know that the presentation is live, convert the
  2615.           // timeline to live.
  2616.           this.changePresentationTimelineToLive_(playlist);
  2617.         }
  2619.         // Copy values from the real stream info to our initial one.
  2620.         streamInfo.minTimestamp = realStreamInfo.minTimestamp;
  2621.         streamInfo.maxTimestamp = realStreamInfo.maxTimestamp;
  2622.         streamInfo.canSkipSegments = realStreamInfo.canSkipSegments;
  2623.         streamInfo.canBlockReload = realStreamInfo.canBlockReload;
  2624.         streamInfo.hasEndList = realStreamInfo.hasEndList;
  2625.         streamInfo.mediaSequenceToStartTime =
  2626.             realStreamInfo.mediaSequenceToStartTime;
  2627.         streamInfo.nextMediaSequence = realStreamInfo.nextMediaSequence;
  2628.         streamInfo.nextPart = realStreamInfo.nextPart;
  2629.         streamInfo.loadedOnce = true;
  2630.         stream.segmentIndex = realStream.segmentIndex;
  2631.         stream.encrypted = realStream.encrypted;
  2632.         stream.drmInfos = realStream.drmInfos;
  2633.         stream.keyIds = realStream.keyIds;
  2634.         stream.mimeType = realStream.mimeType;
  2635.         stream.bandwidth = stream.bandwidth || realStream.bandwidth;
  2636.         stream.codecs = stream.codecs || realStream.codecs;
  2637.         stream.closedCaptions =
  2638.             stream.closedCaptions || realStream.closedCaptions;
  2639.         stream.width = stream.width || realStream.width;
  2640.         stream.height = stream.height || realStream.height;
  2641.         stream.hdr = stream.hdr || realStream.hdr;
  2642.         stream.colorGamut = stream.colorGamut || realStream.colorGamut;
  2643.         stream.frameRate = stream.frameRate || realStream.frameRate;
  2644.         if (stream.language == 'und' && realStream.language != 'und') {
  2645.           stream.language = realStream.language;
  2646.         }
  2647.         stream.language = stream.language || realStream.language;
  2648.         stream.channelsCount = stream.channelsCount || realStream.channelsCount;
  2649.         stream.audioSamplingRate =
  2650.             stream.audioSamplingRate || realStream.audioSamplingRate;
  2651.         this.setFullTypeForStream_(stream);
  2653.         // Since we lazy-loaded this content, the player may need to create new
  2654.         // sessions for the DRM info in this stream.
  2655.         if (stream.drmInfos.length) {
  2656.           this.playerInterface_.newDrmInfo(stream);
  2657.         }
  2659.         let closedCaptionsUpdated = false;
  2660.         if ((!closedCaptions && stream.closedCaptions) ||
  2661.           (closedCaptions && stream.closedCaptions &&
  2662.           closedCaptions.size != stream.closedCaptions.size)) {
  2663.           closedCaptionsUpdated = true;
  2664.         }
  2666.         if (this.manifest_ && closedCaptionsUpdated) {
  2667.           this.playerInterface_.makeTextStreamsForClosedCaptions(
  2668.               this.manifest_);
  2669.         }
  2671.         if (type == ContentType.VIDEO || type == ContentType.AUDIO) {
  2672.           for (const otherStreamInfo of this.uriToStreamInfosMap_.values()) {
  2673.             if (!otherStreamInfo.loadedOnce && otherStreamInfo.type == type &&
  2674.                 !otherStreamInfo.stream.isAudioMuxedInVideo) {
  2675.               // To aid manifest filtering, assume before loading that all video
  2676.               // renditions have the same MIME type.  (And likewise for audio.)
  2677.               otherStreamInfo.stream.mimeType = realStream.mimeType;
  2678.               this.setFullTypeForStream_(otherStreamInfo.stream);
  2679.             }
  2680.           }
  2681.         }
  2683.         if (type == ContentType.TEXT) {
  2684.           const firstSegment = realStream.segmentIndex.earliestReference();
  2685.           if (firstSegment && firstSegment.initSegmentReference) {
  2686.             stream.mimeType = 'application/mp4';
  2687.             this.setFullTypeForStream_(stream);
  2688.           }
  2689.         }
  2691.         const qualityInfo =
  2692.             shaka.media.QualityObserver.createQualityInfo(stream);
  2693.         stream.segmentIndex.forEachTopLevelReference((reference) => {
  2694.           if (reference.initSegmentReference) {
  2695.             reference.initSegmentReference.mediaQuality = qualityInfo;
  2696.           }
  2697.         });
  2699.         // Add finishing touches to the stream that can only be done once we
  2700.         // have more full context on the media as a whole.
  2701.         if (this.hasEnoughInfoToFinalizeStreams_()) {
  2702.           if (!this.streamsFinalized_) {
  2703.             // Mark this manifest as having been finalized, so we don't go
  2704.             // through this whole process of finishing touches a second time.
  2705.             this.streamsFinalized_ = true;
  2706.             // Finalize all of the currently-loaded streams.
  2707.             const streamInfos = Array.from(this.uriToStreamInfosMap_.values());
  2708.             const activeStreamInfos =
  2709.                 streamInfos.filter((s) => s.stream.segmentIndex);
  2710.             this.finalizeStreams_(activeStreamInfos);
  2711.             // With the addition of this new stream, we now have enough info to
  2712.             // figure out how long the streams should be. So process all streams
  2713.             // we have downloaded up until this point.
  2714.             this.determineDuration_();
  2715.             // Finally, start the update timer, if this asset has been
  2716.             // determined to be a livestream.
  2717.             const delay = this.getUpdatePlaylistDelay_();
  2718.             if (delay > 0) {
  2719.               this.updatePlaylistTimer_.tickAfter(/* seconds= */ delay);
  2720.             }
  2721.           } else {
  2722.             // We don't need to go through the full process; just finalize this
  2723.             // single stream.
  2724.             this.finalizeStreams_([streamInfo]);
  2725.           }
  2726.         }
  2728.         this.processDateRangeTags_(
  2729.             playlist.tags, stream.type, mediaVariables, getUris);
  2731.         if (this.manifest_) {
  2732.           this.manifest_.startTime = this.startTime_;
  2733.         }
  2734.       } catch (e) {
  2735.         stream.closeSegmentIndex();
  2736.         if (e.code === shaka.util.Error.Code.OPERATION_ABORTED) {
  2737.           return;
  2738.         }
  2739.         const handled = this.playerInterface_.disableStream(stream);
  2740.         if (!handled) {
  2741.           throw e;
  2742.         }
  2743.       }
  2744.     };
  2746.     /** @type {Promise} */
  2747.     let creationPromise = null;
  2748.     /** @type {!shaka.net.NetworkingEngine.PendingRequest} */
  2749.     let pendingRequest;
  2750.     const safeCreateSegmentIndex = () => {
  2751.       // An operation is already in progress.  The second and subsequent
  2752.       // callers receive the same Promise as the first caller, and only one
  2753.       // download operation will occur.
  2754.       if (creationPromise) {
  2755.         return creationPromise;
  2756.       }
  2758.       if (stream.isAudioMuxedInVideo) {
  2759.         const segmentIndex = new shaka.media.SegmentIndex([]);
  2760.         stream.segmentIndex = segmentIndex;
  2761.         return Promise.resolve();
  2762.       }
  2764.       // Create a new PendingRequest to be able to cancel this specific
  2765.       // download.
  2766.       pendingRequest = this.requestManifest_(streamInfo.getUris(),
  2767.           /* isPlaylist= */ true);
  2769.       // Create a Promise tied to the outcome of downloadSegmentIndex().  If
  2770.       // downloadSegmentIndex is rejected, creationPromise will also be
  2771.       // rejected.
  2772.       creationPromise = new Promise((resolve) => {
  2773.         resolve(downloadSegmentIndex(pendingRequest));
  2774.       });
  2775.       return creationPromise;
  2776.     };
  2778.     stream.createSegmentIndex = safeCreateSegmentIndex;
  2780.     stream.closeSegmentIndex = () => {
  2781.       // If we're mid-creation, cancel it.
  2782.       if (creationPromise && !stream.segmentIndex) {
  2783.         pendingRequest.abort();
  2784.       }
  2785.       // If we have a segment index, release it.
  2786.       if (stream.segmentIndex) {
  2787.         stream.segmentIndex.release();
  2788.         stream.segmentIndex = null;
  2789.       }
  2790.       // Clear the creation Promise so that a new operation can begin.
  2791.       creationPromise = null;
  2792.     };
  2794.     return streamInfo;
  2795.   }
  2797.   /**
  2798.    * @return {number}
  2799.    * @private
  2800.    */
  2801.   getMinDuration_() {
  2802.     let minDuration = Infinity;
  2803.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  2804.       if (streamInfo.stream.segmentIndex && streamInfo.stream.type != 'text' &&
  2805.           !streamInfo.stream.isAudioMuxedInVideo) {
  2806.         // Since everything is already offset to 0 (either by sync or by being
  2807.         // VOD), only maxTimestamp is necessary to compute the duration.
  2808.         minDuration = Math.min(minDuration, streamInfo.maxTimestamp);
  2809.       }
  2810.     }
  2811.     return minDuration;
  2812.   }
  2814.   /**
  2815.    * @return {number}
  2816.    * @private
  2817.    */
  2818.   getLiveDuration_() {
  2819.     let maxTimestamp = Infinity;
  2820.     let minTimestamp = Infinity;
  2821.     for (const streamInfo of this.uriToStreamInfosMap_.values()) {
  2822.       if (streamInfo.stream.segmentIndex && streamInfo.stream.type != 'text' &&
  2823.           !streamInfo.stream.isAudioMuxedInVideo) {
  2824.         maxTimestamp = Math.min(maxTimestamp, streamInfo.maxTimestamp);
  2825.         minTimestamp = Math.min(minTimestamp, streamInfo.minTimestamp);
  2826.       }
  2827.     }
  2828.     return maxTimestamp - minTimestamp;
  2829.   }
  2831.   /**
  2832.    * @param {!Array<!shaka.extern.Stream>} streams
  2833.    * @private
  2834.    */
  2835.   notifySegmentsForStreams_(streams) {
  2836.     const references = [];
  2837.     for (const stream of streams) {
  2838.       if (!stream.segmentIndex) {
  2839.         // The stream was closed since the list of streams was built.
  2840.         continue;
  2841.       }
  2842.       stream.segmentIndex.forEachTopLevelReference((reference) => {
  2843.         references.push(reference);
  2844.       });
  2845.     }
  2846.     this.presentationTimeline_.notifySegments(references);
  2847.   }
  2849.   /**
  2850.    * @param {!Array<!shaka.hls.HlsParser.StreamInfo>} streamInfos
  2851.    * @private
  2852.    */
  2853.   finalizeStreams_(streamInfos) {
  2854.     if (!this.isLive_()) {
  2855.       const minDuration = this.getMinDuration_();
  2856.       for (const streamInfo of streamInfos) {
  2857.         streamInfo.stream.segmentIndex.fit(/* periodStart= */ 0, minDuration);
  2858.       }
  2859.     }
  2860.     this.notifySegmentsForStreams_(streamInfos.map((s) => s.stream));
  2862.     const activeStreamInfos = Array.from(this.uriToStreamInfosMap_.values())
  2863.         .filter((s) => s.stream.segmentIndex);
  2864.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  2865.     const hasAudio =
  2866.         activeStreamInfos.some((s) => s.stream.type == ContentType.AUDIO);
  2867.     const hasVideo =
  2868.         activeStreamInfos.some((s) => s.stream.type == ContentType.VIDEO);
  2870.     const liveWithNoProgramDateTime =
  2871.         this.isLive_() && !this.usesProgramDateTime_;
  2872.     const vodWithOnlyAudioOrVideo = !this.isLive_() &&
  2873.         this.usesProgramDateTime_ && !(hasAudio && hasVideo);
  2874.     if (this.config_.hls.ignoreManifestProgramDateTime ||
  2875.         liveWithNoProgramDateTime || vodWithOnlyAudioOrVideo) {
  2876.       this.syncStreamsWithSequenceNumber_(
  2877.           streamInfos, liveWithNoProgramDateTime);
  2878.     } else {
  2879.       this.syncStreamsWithProgramDateTime_(streamInfos);
  2880.       if (this.config_.hls.ignoreManifestProgramDateTimeForTypes.length > 0) {
  2881.         this.syncStreamsWithSequenceNumber_(streamInfos);
  2882.       }
  2883.     }
  2884.   }
  2886.   /**
  2887.    * @param {string} type
  2888.    * @return {boolean}
  2889.    * @private
  2890.    */
  2891.   ignoreManifestProgramDateTimeFor_(type) {
  2892.     if (this.config_.hls.ignoreManifestProgramDateTime) {
  2893.       return true;
  2894.     }
  2895.     const forTypes = this.config_.hls.ignoreManifestProgramDateTimeForTypes;
  2896.     return forTypes.includes(type);
  2897.   }
  2899.   /**
  2900.    * There are some values on streams that can only be set once we know about
  2901.    * both the video and audio content, if present.
  2902.    * This checks if there is at least one video downloaded (if the media has
  2903.    * video), and that there is at least one audio downloaded (if the media has
  2904.    * audio).
  2905.    * @return {boolean}
  2906.    * @private
  2907.    */
  2908.   hasEnoughInfoToFinalizeStreams_() {
  2909.     if (!this.manifest_) {
  2910.       return false;
  2911.     }
  2912.     const videos = [];
  2913.     const audios = [];
  2914.     for (const variant of this.manifest_.variants) {
  2915.       if (variant.video) {
  2916.         videos.push(variant.video);
  2917.       }
  2918.       if (variant.audio) {
  2919.         audios.push(variant.audio);
  2920.       }
  2921.     }
  2922.     if (videos.length > 0 && !videos.some((stream) => stream.segmentIndex)) {
  2923.       return false;
  2924.     }
  2925.     if (audios.length > 0 && !audios.some((stream) => stream.segmentIndex)) {
  2926.       return false;
  2927.     }
  2928.     return true;
  2929.   }
  2931.   /**
  2932.    * @param {number} streamId
  2933.    * @param {!Map<string, string>} variables
  2934.    * @param {!shaka.hls.Playlist} playlist
  2935.    * @param {function(): !Array<string>} getUris
  2936.    * @param {string} codecs
  2937.    * @param {string} type
  2938.    * @param {?string} languageValue
  2939.    * @param {boolean} primary
  2940.    * @param {?string} name
  2941.    * @param {?number} channelsCount
  2942.    * @param {Map<string, string>} closedCaptions
  2943.    * @param {?string} characteristics
  2944.    * @param {boolean} forced
  2945.    * @param {?number} sampleRate
  2946.    * @param {boolean} spatialAudio
  2947.    * @param {(string|undefined)} mimeType
  2948.    * @param {boolean=} requestBasicInfo
  2949.    * @param {boolean=} allowOverrideMimeType
  2950.    * @return {!Promise<!shaka.hls.HlsParser.StreamInfo>}
  2951.    * @private
  2952.    */
  2953.   async convertParsedPlaylistIntoStreamInfo_(streamId, variables, playlist,
  2954.       getUris, codecs, type, languageValue, primary, name,
  2955.       channelsCount, closedCaptions, characteristics, forced, sampleRate,
  2956.       spatialAudio, mimeType = undefined, requestBasicInfo = true,
  2957.       allowOverrideMimeType = true) {
  2958.     const playlistSegments = playlist.segments || [];
  2959.     const allAreMissing = playlistSegments.every((seg) => {
  2960.       if (shaka.hls.Utils.getFirstTagWithName(seg.tags, 'EXT-X-GAP')) {
  2961.         return true;
  2962.       }
  2963.       return false;
  2964.     });
  2966.     if (!playlistSegments.length || allAreMissing) {
  2967.       throw new shaka.util.Error(
  2968.           shaka.util.Error.Severity.CRITICAL,
  2969.           shaka.util.Error.Category.MANIFEST,
  2970.           shaka.util.Error.Code.HLS_EMPTY_MEDIA_PLAYLIST);
  2971.     }
  2973.     this.determinePresentationType_(playlist);
  2975.     if (this.isLive_()) {
  2976.       this.determineLastTargetDuration_(playlist);
  2977.     }
  2979.     const mediaSequenceToStartTime = this.isLive_() ?
  2980.         this.mediaSequenceToStartTimeByType_.get(type) : new Map();
  2982.     const {segments, bandwidth} = this.createSegments_(
  2983.         playlist, mediaSequenceToStartTime, variables, getUris, type);
  2985.     let width = null;
  2986.     let height = null;
  2987.     let videoRange = null;
  2988.     let colorGamut = null;
  2989.     let frameRate = null;
  2990.     if (segments.length > 0 && requestBasicInfo) {
  2991.       const basicInfo = await this.getBasicInfoFromSegments_(segments);
  2993.       type = basicInfo.type;
  2994.       languageValue = basicInfo.language;
  2995.       channelsCount = basicInfo.channelCount;
  2996.       sampleRate = basicInfo.sampleRate;
  2997.       if (!this.config_.disableText) {
  2998.         closedCaptions = basicInfo.closedCaptions;
  2999.       }
  3001.       height = basicInfo.height;
  3002.       width = basicInfo.width;
  3003.       videoRange = basicInfo.videoRange;
  3004.       colorGamut = basicInfo.colorGamut;
  3005.       frameRate = basicInfo.frameRate;
  3007.       if (allowOverrideMimeType) {
  3008.         mimeType = basicInfo.mimeType;
  3009.         codecs = basicInfo.codecs;
  3010.       }
  3011.     }
  3013.     if (!mimeType) {
  3014.       mimeType = await this.guessMimeType_(type, codecs, segments);
  3016.       // Some manifests don't say what text codec they use, this is a problem
  3017.       // if the cmft extension is used because we identify the mimeType as
  3018.       // application/mp4. In this case if we don't detect initialization
  3019.       // segments, we assume that the mimeType is text/vtt.
  3020.       if (type == shaka.util.ManifestParserUtils.ContentType.TEXT &&
  3021.           !codecs && mimeType == 'application/mp4' &&
  3022.           segments[0] && !segments[0].initSegmentReference) {
  3023.         mimeType = 'text/vtt';
  3024.       }
  3025.     }
  3027.     const {drmInfos, keyIds, encrypted, aesEncrypted} =
  3028.         await this.parseDrmInfo_(playlist, mimeType, getUris, variables);
  3030.     if (encrypted && !drmInfos.length && !aesEncrypted) {
  3031.       throw new shaka.util.Error(
  3032.           shaka.util.Error.Severity.CRITICAL,
  3033.           shaka.util.Error.Category.MANIFEST,
  3034.           shaka.util.Error.Code.HLS_KEYFORMATS_NOT_SUPPORTED);
  3035.     }
  3037.     const stream = this.makeStreamObject_(streamId, codecs, type,
  3038.         languageValue, primary, name, channelsCount, closedCaptions,
  3039.         characteristics, forced, sampleRate, spatialAudio);
  3040.     stream.encrypted = encrypted && !aesEncrypted;
  3041.     stream.drmInfos = drmInfos;
  3042.     stream.keyIds = keyIds;
  3043.     stream.mimeType = mimeType;
  3044.     if (bandwidth) {
  3045.       stream.bandwidth = bandwidth;
  3046.     }
  3047.     this.setFullTypeForStream_(stream);
  3049.     if (type == shaka.util.ManifestParserUtils.ContentType.VIDEO &&
  3050.         (width || height || videoRange || colorGamut)) {
  3051.       this.addVideoAttributes_(stream, width, height,
  3052.           frameRate, videoRange, /* videoLayout= */ null, colorGamut);
  3053.     }
  3055.     // This new calculation is necessary for Low Latency streams.
  3056.     if (this.isLive_()) {
  3057.       this.determineLastTargetDuration_(playlist);
  3058.     }
  3060.     const firstStartTime = segments[0].startTime;
  3061.     const lastSegment = segments[segments.length - 1];
  3062.     const lastEndTime = lastSegment.endTime;
  3063.     /** @type {!shaka.media.SegmentIndex} */
  3064.     const segmentIndex = new shaka.media.SegmentIndex(segments);
  3065.     stream.segmentIndex = segmentIndex;
  3067.     const serverControlTag = shaka.hls.Utils.getFirstTagWithName(
  3068.         playlist.tags, 'EXT-X-SERVER-CONTROL');
  3069.     const canSkipSegments = serverControlTag ?
  3070.           serverControlTag.getAttribute('CAN-SKIP-UNTIL') != null : false;
  3071.     const canBlockReload = serverControlTag ?
  3072.           serverControlTag.getAttribute('CAN-BLOCK-RELOAD') != null : false;
  3074.     const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  3075.         playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  3077.     const {nextMediaSequence, nextPart} =
  3078.         this.getNextMediaSequenceAndPart_(mediaSequenceNumber, segments);
  3080.     return {
  3081.       stream,
  3082.       type,
  3083.       redirectUris: [],
  3084.       getUris,
  3085.       minTimestamp: firstStartTime,
  3086.       maxTimestamp: lastEndTime,
  3087.       canSkipSegments,
  3088.       canBlockReload,
  3089.       hasEndList: false,
  3090.       firstSequenceNumber: -1,
  3091.       nextMediaSequence,
  3092.       nextPart,
  3093.       mediaSequenceToStartTime,
  3094.       loadedOnce: false,
  3095.     };
  3096.   }
  3098.   /**
  3099.    * Get the next msn and part
  3100.    *
  3101.    * @param {number} mediaSequenceNumber
  3102.    * @param {!Array<!shaka.media.SegmentReference>} segments
  3103.    * @return {{nextMediaSequence: number, nextPart:number}}}
  3104.    * @private
  3105.    */
  3106.   getNextMediaSequenceAndPart_(mediaSequenceNumber, segments) {
  3107.     const currentMediaSequence = mediaSequenceNumber + segments.length - 1;
  3108.     let nextMediaSequence = currentMediaSequence;
  3109.     let nextPart = -1;
  3110.     if (!segments.length) {
  3111.       nextMediaSequence++;
  3112.       return {
  3113.         nextMediaSequence,
  3114.         nextPart,
  3115.       };
  3116.     }
  3117.     const lastSegment = segments[segments.length - 1];
  3118.     const partialReferences = lastSegment.partialReferences;
  3119.     if (!lastSegment.partialReferences.length) {
  3120.       nextMediaSequence++;
  3121.       if (lastSegment.hasByterangeOptimization()) {
  3122.         nextPart = 0;
  3123.       }
  3124.       return {
  3125.         nextMediaSequence,
  3126.         nextPart,
  3127.       };
  3128.     }
  3129.     nextPart = partialReferences.length - 1;
  3130.     const lastPartialReference =
  3131.         partialReferences[partialReferences.length - 1];
  3132.     if (!lastPartialReference.isPreload()) {
  3133.       nextMediaSequence++;
  3134.       nextPart = 0;
  3135.     }
  3136.     return {
  3137.       nextMediaSequence,
  3138.       nextPart,
  3139.     };
  3140.   }
  3143.   /**
  3144.    * Creates a stream object with the given parameters.
  3145.    * The parameters that are passed into here are only the things that can be
  3146.    * known without downloading the media playlist; other values must be set
  3147.    * manually on the object after creation.
  3148.    * @param {number} id
  3149.    * @param {string} codecs
  3150.    * @param {string} type
  3151.    * @param {?string} languageValue
  3152.    * @param {boolean} primary
  3153.    * @param {?string} name
  3154.    * @param {?number} channelsCount
  3155.    * @param {Map<string, string>} closedCaptions
  3156.    * @param {?string} characteristics
  3157.    * @param {boolean} forced
  3158.    * @param {?number} sampleRate
  3159.    * @param {boolean} spatialAudio
  3160.    * @return {!shaka.extern.Stream}
  3161.    * @private
  3162.    */
  3163.   makeStreamObject_(id, codecs, type, languageValue, primary, name,
  3164.       channelsCount, closedCaptions, characteristics, forced, sampleRate,
  3165.       spatialAudio) {
  3166.     // Fill out a "best-guess" mimeType, for now. It will be replaced once the
  3167.     // stream is lazy-loaded.
  3168.     const mimeType = this.guessMimeTypeBeforeLoading_(type, codecs) ||
  3169.         this.guessMimeTypeFallback_(type);
  3170.     const roles = [];
  3171.     if (characteristics) {
  3172.       for (const characteristic of characteristics.split(',')) {
  3173.         roles.push(characteristic);
  3174.       }
  3175.     }
  3177.     let kind = undefined;
  3178.     let accessibilityPurpose = null;
  3179.     if (type == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  3180.       if (roles.includes('public.accessibility.transcribes-spoken-dialog') &&
  3181.           roles.includes('public.accessibility.describes-music-and-sound')) {
  3182.         kind = shaka.util.ManifestParserUtils.TextStreamKind.CLOSED_CAPTION;
  3183.       } else {
  3184.         kind = shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE;
  3185.       }
  3186.     } else {
  3187.       if (roles.includes('public.accessibility.describes-video')) {
  3188.         accessibilityPurpose =
  3189.               shaka.media.ManifestParser.AccessibilityPurpose.VISUALLY_IMPAIRED;
  3190.       }
  3191.     }
  3193.     // If there are no roles, and we have defaulted to the subtitle "kind" for
  3194.     // this track, add the implied subtitle role.
  3195.     if (!roles.length &&
  3196.         kind === shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE) {
  3197.       roles.push(shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE);
  3198.     }
  3200.     const stream = {
  3201.       id: this.globalId_++,
  3202.       originalId: name,
  3203.       groupId: null,
  3204.       createSegmentIndex: () => Promise.resolve(),
  3205.       segmentIndex: null,
  3206.       mimeType,
  3207.       codecs,
  3208.       kind: (type == shaka.util.ManifestParserUtils.ContentType.TEXT) ?
  3209.           shaka.util.ManifestParserUtils.TextStreamKind.SUBTITLE : undefined,
  3210.       encrypted: false,
  3211.       drmInfos: [],
  3212.       keyIds: new Set(),
  3213.       language: this.getLanguage_(languageValue),
  3214.       originalLanguage: languageValue,
  3215.       label: name,  // For historical reasons, since before "originalId".
  3216.       type,
  3217.       primary,
  3218.       // TODO: trick mode
  3219.       trickModeVideo: null,
  3220.       dependencyStream: null,
  3221.       emsgSchemeIdUris: null,
  3222.       frameRate: undefined,
  3223.       pixelAspectRatio: undefined,
  3224.       width: undefined,
  3225.       height: undefined,
  3226.       bandwidth: undefined,
  3227.       roles,
  3228.       forced,
  3229.       channelsCount,
  3230.       audioSamplingRate: sampleRate,
  3231.       spatialAudio,
  3232.       closedCaptions,
  3233.       hdr: undefined,
  3234.       colorGamut: undefined,
  3235.       videoLayout: undefined,
  3236.       tilesLayout: undefined,
  3237.       accessibilityPurpose: accessibilityPurpose,
  3238.       external: false,
  3239.       fastSwitching: false,
  3240.       fullMimeTypes: new Set(),
  3241.       isAudioMuxedInVideo: false,
  3242.       baseOriginalId: null,
  3243.     };
  3244.     this.setFullTypeForStream_(stream);
  3245.     return stream;
  3246.   }
  3248.   /**
  3249.    * @param {!shaka.hls.Playlist} playlist
  3250.    * @param {string} mimeType
  3251.    * @param {function(): !Array<string>} getUris
  3252.    * @param {?Map<string, string>=} variables
  3253.    * @return {Promise<{
  3254.    *   drmInfos: !Array<shaka.extern.DrmInfo>,
  3255.    *   keyIds: !Set<string>,
  3256.    *   encrypted: boolean,
  3257.    *   aesEncrypted: boolean
  3258.    * }>}
  3259.    * @private
  3260.    */
  3261.   async parseDrmInfo_(playlist, mimeType, getUris, variables) {
  3262.     /** @type {!Map<!shaka.hls.Tag, ?shaka.media.InitSegmentReference>} */
  3263.     const drmTagsMap = new Map();
  3264.     if (!this.config_.ignoreDrmInfo && playlist.segments) {
  3265.       for (const segment of playlist.segments) {
  3266.         const segmentKeyTags = shaka.hls.Utils.filterTagsByName(segment.tags,
  3267.             'EXT-X-KEY');
  3268.         let initSegmentRef = null;
  3269.         if (segmentKeyTags.length) {
  3270.           initSegmentRef = this.getInitSegmentReference_(playlist,
  3271.               segment.tags, getUris, variables);
  3272.           for (const segmentKeyTag of segmentKeyTags) {
  3273.             drmTagsMap.set(segmentKeyTag, initSegmentRef);
  3274.           }
  3275.         }
  3276.       }
  3277.     }
  3279.     let encrypted = false;
  3280.     let aesEncrypted = false;
  3282.     /** @type {!Array<shaka.extern.DrmInfo>}*/
  3283.     const drmInfos = [];
  3284.     const keyIds = new Set();
  3286.     for (const [key, value] of drmTagsMap) {
  3287.       const drmTag = /** @type {!shaka.hls.Tag} */ (key);
  3288.       const initSegmentRef =
  3289.       /** @type {?shaka.media.InitSegmentReference} */ (value);
  3290.       const method = drmTag.getRequiredAttrValue('METHOD');
  3291.       if (method != 'NONE') {
  3292.         encrypted = true;
  3294.         // According to the HLS spec, KEYFORMAT is optional and implicitly
  3295.         // defaults to "identity".
  3296.         // https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-4.4.4.4
  3297.         const keyFormat =
  3298.             drmTag.getAttributeValue('KEYFORMAT') || 'identity';
  3299.         let drmInfo = null;
  3301.         if (this.isAesMethod_(method)) {
  3302.           // These keys are handled separately.
  3303.           aesEncrypted = true;
  3304.           continue;
  3305.         } else if (keyFormat == 'identity') {
  3306.           // eslint-disable-next-line no-await-in-loop
  3307.           drmInfo = await this.identityDrmParser_(
  3308.               drmTag, mimeType, getUris, initSegmentRef, variables);
  3309.         } else {
  3310.           const drmParser =
  3311.               this.keyFormatsToDrmParsers_.get(keyFormat);
  3312.           drmInfo = drmParser ?
  3313.             // eslint-disable-next-line no-await-in-loop
  3314.             await drmParser(drmTag, mimeType, initSegmentRef) :
  3315.             null;
  3316.         }
  3317.         if (drmInfo) {
  3318.           if (drmInfo.keyIds) {
  3319.             for (const keyId of drmInfo.keyIds) {
  3320.               keyIds.add(keyId);
  3321.             }
  3322.           }
  3323.           drmInfos.push(drmInfo);
  3324.         } else {
  3325.           shaka.log.warning('Unsupported HLS KEYFORMAT', keyFormat);
  3326.         }
  3327.       }
  3328.     }
  3330.     return {drmInfos, keyIds, encrypted, aesEncrypted};
  3331.   }
  3333.   /**
  3334.    * @param {!shaka.hls.Tag} drmTag
  3335.    * @param {!shaka.hls.Playlist} playlist
  3336.    * @param {function(): !Array<string>} getUris
  3337.    * @param {?Map<string, string>=} variables
  3338.    * @return {!shaka.extern.aesKey}
  3339.    * @private
  3340.    */
  3341.   parseAESDrmTag_(drmTag, playlist, getUris, variables) {
  3342.     // Check if the Web Crypto API is available.
  3343.     if (!window.crypto || !window.crypto.subtle) {
  3344.       shaka.log.alwaysWarn('Web Crypto API is not available to decrypt ' +
  3345.           'AES. (Web Crypto only exists in secure origins like https)');
  3346.       throw new shaka.util.Error(
  3347.           shaka.util.Error.Severity.CRITICAL,
  3348.           shaka.util.Error.Category.MANIFEST,
  3349.           shaka.util.Error.Code.NO_WEB_CRYPTO_API);
  3350.     }
  3352.     // HLS RFC 8216 Section 5.2:
  3353.     // An EXT-X-KEY tag with a KEYFORMAT of "identity" that does not have an IV
  3354.     // attribute indicates that the Media Sequence Number is to be used as the
  3355.     // IV when decrypting a Media Segment, by putting its big-endian binary
  3356.     // representation into a 16-octet (128-bit) buffer and padding (on the left)
  3357.     // with zeros.
  3358.     let firstMediaSequenceNumber = 0;
  3359.     let iv;
  3360.     const ivHex = drmTag.getAttributeValue('IV', '');
  3361.     if (!ivHex) {
  3362.       // Media Sequence Number will be used as IV.
  3363.       firstMediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  3364.           playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  3365.     } else {
  3366.       // Exclude 0x at the start of string.
  3367.       iv = shaka.util.Uint8ArrayUtils.fromHex(ivHex.substr(2));
  3368.       if (iv.byteLength != 16) {
  3369.         throw new shaka.util.Error(
  3370.             shaka.util.Error.Severity.CRITICAL,
  3371.             shaka.util.Error.Category.MANIFEST,
  3372.             shaka.util.Error.Code.AES_128_INVALID_IV_LENGTH);
  3373.       }
  3374.     }
  3376.     const keyUris = shaka.hls.Utils.constructSegmentUris(
  3377.         getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  3378.     const keyMapKey = keyUris.sort().join('');
  3379.     const aesKeyInfoKey =
  3380.         `${drmTag.toString()}-${firstMediaSequenceNumber}-${keyMapKey}`;
  3381.     if (!this.aesKeyInfoMap_.has(aesKeyInfoKey)) {
  3382.       // Default AES-128
  3383.       const keyInfo = {
  3384.         bitsKey: 128,
  3385.         blockCipherMode: 'CBC',
  3386.         iv,
  3387.         firstMediaSequenceNumber,
  3388.       };
  3390.       const method = drmTag.getRequiredAttrValue('METHOD');
  3391.       switch (method) {
  3392.         case 'AES-256':
  3393.           keyInfo.bitsKey = 256;
  3394.           break;
  3395.         case 'AES-256-CTR':
  3396.           keyInfo.bitsKey = 256;
  3397.           keyInfo.blockCipherMode = 'CTR';
  3398.           break;
  3399.       }
  3401.       // Don't download the key object until the segment is parsed, to avoid a
  3402.       // startup delay for long manifests with lots of keys.
  3403.       keyInfo.fetchKey = async () => {
  3404.         if (!this.aesKeyMap_.has(keyMapKey)) {
  3405.           const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  3406.           const request = shaka.net.NetworkingEngine.makeRequest(
  3407.               keyUris, this.config_.retryParameters);
  3408.           const keyResponse = this.makeNetworkRequest_(request, requestType)
  3409.               .promise;
  3410.           this.aesKeyMap_.set(keyMapKey, keyResponse);
  3411.         }
  3412.         const keyResponse = await this.aesKeyMap_.get(keyMapKey);
  3414.         // keyResponse.status is undefined when URI is "data:text/plain;base64,"
  3415.         if (!keyResponse.data ||
  3416.             keyResponse.data.byteLength != (keyInfo.bitsKey / 8)) {
  3417.           throw new shaka.util.Error(
  3418.               shaka.util.Error.Severity.CRITICAL,
  3419.               shaka.util.Error.Category.MANIFEST,
  3420.               shaka.util.Error.Code.AES_128_INVALID_KEY_LENGTH);
  3421.         }
  3423.         const algorithm = {
  3424.           name: keyInfo.blockCipherMode == 'CTR' ? 'AES-CTR' : 'AES-CBC',
  3425.           length: keyInfo.bitsKey,
  3426.         };
  3427.         keyInfo.cryptoKey = await window.crypto.subtle.importKey(
  3428.             'raw', keyResponse.data, algorithm, true, ['decrypt']);
  3429.         keyInfo.fetchKey = undefined; // No longer needed.
  3430.       };
  3431.       this.aesKeyInfoMap_.set(aesKeyInfoKey, keyInfo);
  3432.     }
  3433.     return this.aesKeyInfoMap_.get(aesKeyInfoKey);
  3434.   }
  3437.   /**
  3438.    * @param {!shaka.hls.Playlist} playlist
  3439.    * @private
  3440.    */
  3441.   determineStartTime_(playlist) {
  3442.     // If we already have a starttime we avoid processing this again.
  3443.     if (this.startTime_ != null) {
  3444.       return;
  3445.     }
  3446.     const startTimeTag =
  3447.         shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-START');
  3448.     if (startTimeTag) {
  3449.       this.startTime_ =
  3450.           Number(startTimeTag.getRequiredAttrValue('TIME-OFFSET'));
  3451.     }
  3452.   }
  3455.   /**
  3456.    * @param {!shaka.hls.Playlist} playlist
  3457.    * @private
  3458.    */
  3459.   determinePresentationType_(playlist) {
  3460.     const PresentationType = shaka.hls.HlsParser.PresentationType_;
  3461.     const presentationTypeTag =
  3462.         shaka.hls.Utils.getFirstTagWithName(playlist.tags,
  3463.             'EXT-X-PLAYLIST-TYPE');
  3464.     const endListTag =
  3465.         shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-ENDLIST');
  3467.     const isVod = (presentationTypeTag && presentationTypeTag.value == 'VOD') ||
  3468.         endListTag;
  3469.     const isEvent = presentationTypeTag &&
  3470.         presentationTypeTag.value == 'EVENT' && !isVod;
  3471.     const isLive = !isVod && !isEvent;
  3473.     if (isVod) {
  3474.       this.setPresentationType_(PresentationType.VOD);
  3475.     } else {
  3476.       // If it's not VOD, it must be presentation type LIVE or an ongoing EVENT.
  3477.       if (isLive) {
  3478.         this.setPresentationType_(PresentationType.LIVE);
  3479.       } else {
  3480.         this.setPresentationType_(PresentationType.EVENT);
  3481.       }
  3482.     }
  3483.   }
  3486.   /**
  3487.    * @param {!shaka.hls.Playlist} playlist
  3488.    * @private
  3489.    */
  3490.   determineLastTargetDuration_(playlist) {
  3491.     let lastTargetDuration = Infinity;
  3492.     const segments = playlist.segments;
  3493.     if (segments.length) {
  3494.       let segmentIndex = segments.length - 1;
  3495.       while (segmentIndex >= 0) {
  3496.         const segment = segments[segmentIndex];
  3497.         const extinfTag =
  3498.             shaka.hls.Utils.getFirstTagWithName(segment.tags, 'EXTINF');
  3499.         if (extinfTag) {
  3500.           // The EXTINF tag format is '#EXTINF:<duration>,[<title>]'.
  3501.           // We're interested in the duration part.
  3502.           const extinfValues = extinfTag.value.split(',');
  3503.           lastTargetDuration = Number(extinfValues[0]);
  3504.           break;
  3505.         }
  3506.         segmentIndex--;
  3507.       }
  3508.     }
  3510.     const targetDurationTag = this.getRequiredTag_(playlist.tags,
  3511.         'EXT-X-TARGETDURATION');
  3512.     const targetDuration = Number(targetDurationTag.value);
  3513.     const partialTargetDurationTag =
  3514.       shaka.hls.Utils.getFirstTagWithName(playlist.tags, 'EXT-X-PART-INF');
  3515.     if (partialTargetDurationTag) {
  3516.       this.partialTargetDuration_ = Number(
  3517.           partialTargetDurationTag.getRequiredAttrValue('PART-TARGET'));
  3518.     }
  3519.     // Get the server-recommended min distance from the live edge.
  3520.     const serverControlTag = shaka.hls.Utils.getFirstTagWithName(
  3521.         playlist.tags, 'EXT-X-SERVER-CONTROL');
  3522.     // According to the HLS spec, updates should not happen more often than
  3523.     // once in targetDuration.  It also requires us to only update the active
  3524.     // variant.  We might implement that later, but for now every variant
  3525.     // will be updated.  To get the update period, choose the smallest
  3526.     // targetDuration value across all playlists.
  3527.     // 1. Update the shortest one to use as update period and segment
  3528.     // availability time (for LIVE).
  3529.     if (this.lowLatencyMode_ && this.partialTargetDuration_) {
  3530.       // For low latency streaming, use the partial segment target duration.
  3531.       if (this.lowLatencyByterangeOptimization_) {
  3532.         // We always have at least 1 partial segment part, and most servers
  3533.         // allow you to make a request with _HLS_msn=X&_HLS_part=0 with a
  3534.         // distance of 4 partial segments.  With this we ensure that we
  3535.         // obtain the minimum latency in this type of case.
  3536.         if (this.partialTargetDuration_ * 5 <= lastTargetDuration) {
  3537.           this.lastTargetDuration_ = Math.min(
  3538.               this.partialTargetDuration_, this.lastTargetDuration_);
  3539.         } else {
  3540.           this.lastTargetDuration_ = Math.min(
  3541.               lastTargetDuration, this.lastTargetDuration_);
  3542.         }
  3543.       } else {
  3544.         this.lastTargetDuration_ = Math.min(
  3545.             this.partialTargetDuration_, this.lastTargetDuration_);
  3546.       }
  3547.       // Use 'PART-HOLD-BACK' as the presentation delay for low latency mode.
  3548.       this.lowLatencyPresentationDelay_ = serverControlTag ? Number(
  3549.           serverControlTag.getRequiredAttrValue('PART-HOLD-BACK')) : 0;
  3550.     } else {
  3551.       this.lastTargetDuration_ = Math.min(
  3552.           lastTargetDuration, this.lastTargetDuration_);
  3553.       // Use 'HOLD-BACK' as the presentation delay for default if defined.
  3554.       const holdBack = serverControlTag ?
  3555.           serverControlTag.getAttribute('HOLD-BACK') : null;
  3556.       this.presentationDelay_ = holdBack ? Number(holdBack.value) : 0;
  3557.     }
  3558.     // 2. Update the longest target duration if need be to use as a
  3559.     // presentation delay later.
  3560.     this.maxTargetDuration_ = Math.max(
  3561.         targetDuration, this.maxTargetDuration_);
  3562.   }
  3565.   /**
  3566.    * @param {!shaka.hls.Playlist} playlist
  3567.    * @private
  3568.    */
  3569.   changePresentationTimelineToLive_(playlist) {
  3570.     // The live edge will be calculated from segments, so we don't need to
  3571.     // set a presentation start time.  We will assert later that this is
  3572.     // working as expected.
  3574.     // The HLS spec (RFC 8216) states in 6.3.3:
  3575.     //
  3576.     // "The client SHALL choose which Media Segment to play first ... the
  3577.     // client SHOULD NOT choose a segment that starts less than three target
  3578.     // durations from the end of the Playlist file.  Doing so can trigger
  3579.     // playback stalls."
  3580.     //
  3581.     // We accomplish this in our DASH-y model by setting a presentation
  3582.     // delay of configured value, or 3 segments duration if not configured.
  3583.     // This will be the "live edge" of the presentation.
  3584.     let presentationDelay = 0;
  3585.     if (this.config_.defaultPresentationDelay) {
  3586.       presentationDelay = this.config_.defaultPresentationDelay;
  3587.     } else if (this.lowLatencyPresentationDelay_) {
  3588.       presentationDelay = this.lowLatencyPresentationDelay_;
  3589.     } else if (this.presentationDelay_) {
  3590.       presentationDelay = this.presentationDelay_;
  3591.     } else {
  3592.       const totalSegments = playlist.segments.length;
  3593.       let delaySegments = this.config_.hls.liveSegmentsDelay;
  3594.       if (delaySegments > (totalSegments - 2)) {
  3595.         delaySegments = Math.max(1, totalSegments - 2);
  3596.       }
  3597.       for (let i = totalSegments - delaySegments; i < totalSegments; i++) {
  3598.         const extinfTag = shaka.hls.Utils.getFirstTagWithName(
  3599.             playlist.segments[i].tags, 'EXTINF');
  3600.         if (extinfTag) {
  3601.           const extinfValues = extinfTag.value.split(',');
  3602.           const duration = Number(extinfValues[0]);
  3603.           presentationDelay += Math.ceil(duration);
  3604.         } else {
  3605.           presentationDelay += this.maxTargetDuration_;
  3606.         }
  3607.       }
  3608.     }
  3610.     if (this.startTime_ && this.startTime_ < 0) {
  3611.       presentationDelay = Math.min(-this.startTime_, presentationDelay);
  3612.       this.startTime_ += presentationDelay;
  3613.     }
  3615.     this.presentationTimeline_.setPresentationStartTime(0);
  3616.     this.presentationTimeline_.setDelay(presentationDelay);
  3617.     this.presentationTimeline_.setStatic(false);
  3618.   }
  3620.   /**
  3621.    * Get the InitSegmentReference for a segment if it has a EXT-X-MAP tag.
  3622.    * @param {!shaka.hls.Playlist} playlist
  3623.    * @param {!Array<!shaka.hls.Tag>} tags Segment tags
  3624.    * @param {function(): !Array<string>} getUris
  3625.    * @param {?Map<string, string>=} variables
  3626.    * @return {shaka.media.InitSegmentReference}
  3627.    * @private
  3628.    */
  3629.   getInitSegmentReference_(playlist, tags, getUris, variables) {
  3630.     /** @type {?shaka.hls.Tag} */
  3631.     const mapTag = shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-MAP');
  3633.     if (!mapTag) {
  3634.       return null;
  3635.     }
  3636.     // Map tag example: #EXT-X-MAP:URI="main.mp4",BYTERANGE="720@0"
  3637.     const verbatimInitSegmentUri = mapTag.getRequiredAttrValue('URI');
  3638.     const absoluteInitSegmentUris = shaka.hls.Utils.constructSegmentUris(
  3639.         getUris(), verbatimInitSegmentUri, variables);
  3641.     const mapTagKey = [
  3642.       absoluteInitSegmentUris.toString(),
  3643.       mapTag.getAttributeValue('BYTERANGE', ''),
  3644.     ].join('-');
  3645.     if (!this.mapTagToInitSegmentRefMap_.has(mapTagKey)) {
  3646.       /** @type {shaka.extern.aesKey|undefined} */
  3647.       let aesKey = undefined;
  3648.       let byteRangeTag = null;
  3649.       let encrypted = false;
  3650.       for (const tag of tags) {
  3651.         if (tag.name == 'EXT-X-KEY') {
  3652.           const method = tag.getRequiredAttrValue('METHOD');
  3653.           if (this.isAesMethod_(method) && tag.id < mapTag.id) {
  3654.             encrypted = false;
  3655.             aesKey =
  3656.                 this.parseAESDrmTag_(tag, playlist, getUris, variables);
  3657.           } else {
  3658.             encrypted = method != 'NONE';
  3659.           }
  3660.         } else if (tag.name == 'EXT-X-BYTERANGE' && tag.id < mapTag.id) {
  3661.           byteRangeTag = tag;
  3662.         }
  3663.       }
  3664.       const initSegmentRef = this.createInitSegmentReference_(
  3665.           absoluteInitSegmentUris, mapTag, byteRangeTag, aesKey, encrypted);
  3666.       this.mapTagToInitSegmentRefMap_.set(mapTagKey, initSegmentRef);
  3667.     }
  3668.     return this.mapTagToInitSegmentRefMap_.get(mapTagKey);
  3669.   }
  3671.   /**
  3672.    * Create an InitSegmentReference object for the EXT-X-MAP tag in the media
  3673.    * playlist.
  3674.    * @param {!Array<string>} absoluteInitSegmentUris
  3675.    * @param {!shaka.hls.Tag} mapTag EXT-X-MAP
  3676.    * @param {shaka.hls.Tag=} byteRangeTag EXT-X-BYTERANGE
  3677.    * @param {shaka.extern.aesKey=} aesKey
  3678.    * @param {boolean=} encrypted
  3679.    * @return {!shaka.media.InitSegmentReference}
  3680.    * @private
  3681.    */
  3682.   createInitSegmentReference_(absoluteInitSegmentUris, mapTag, byteRangeTag,
  3683.       aesKey, encrypted) {
  3684.     let startByte = 0;
  3685.     let endByte = null;
  3686.     let byterange = mapTag.getAttributeValue('BYTERANGE');
  3687.     if (!byterange && byteRangeTag) {
  3688.       byterange = byteRangeTag.value;
  3689.     }
  3690.     // If a BYTERANGE attribute is not specified, the segment consists
  3691.     // of the entire resource.
  3692.     if (byterange) {
  3693.       const blocks = byterange.split('@');
  3694.       const byteLength = Number(blocks[0]);
  3695.       startByte = Number(blocks[1]);
  3696.       endByte = startByte + byteLength - 1;
  3698.       if (aesKey) {
  3699.         // MAP segment encrypted with method AES, when served with
  3700.         // HTTP Range, has the unencrypted size specified in the range.
  3701.         // See: https://tools.ietf.org/html/draft-pantos-hls-rfc8216bis-08#section-6.3.6
  3702.         const length = (endByte + 1) - startByte;
  3703.         if (length % 16) {
  3704.           endByte += (16 - (length % 16));
  3705.         }
  3706.       }
  3707.     }
  3709.     const initSegmentRef = new shaka.media.InitSegmentReference(
  3710.         () => absoluteInitSegmentUris,
  3711.         startByte,
  3712.         endByte,
  3713.         /* mediaQuality= */ null,
  3714.         /* timescale= */ null,
  3715.         /* segmentData= */ null,
  3716.         aesKey,
  3717.         encrypted);
  3718.     return initSegmentRef;
  3719.   }
  3721.   /**
  3722.    * Parses one shaka.hls.Segment object into a shaka.media.SegmentReference.
  3723.    *
  3724.    * @param {shaka.media.InitSegmentReference} initSegmentReference
  3725.    * @param {shaka.media.SegmentReference} previousReference
  3726.    * @param {!shaka.hls.Segment} hlsSegment
  3727.    * @param {number} startTime
  3728.    * @param {!Map<string, string>} variables
  3729.    * @param {!shaka.hls.Playlist} playlist
  3730.    * @param {string} type
  3731.    * @param {function(): !Array<string>} getUris
  3732.    * @param {shaka.extern.aesKey=} aesKey
  3733.    * @return {shaka.media.SegmentReference}
  3734.    * @private
  3735.    */
  3736.   createSegmentReference_(
  3737.       initSegmentReference, previousReference, hlsSegment, startTime,
  3738.       variables, playlist, type, getUris, aesKey) {
  3739.     const HlsParser = shaka.hls.HlsParser;
  3741.     const getMimeType = (uri) => {
  3742.       const parsedUri = new goog.Uri(uri);
  3743.       const extension = parsedUri.getPath().split('.').pop();
  3744.       const map = HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_.get(type);
  3745.       let mimeType = map.get(extension);
  3746.       if (!mimeType) {
  3747.         mimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_.get(extension);
  3748.       }
  3749.       return mimeType;
  3750.     };
  3752.     const tags = hlsSegment.tags;
  3753.     const extinfTag =
  3754.         shaka.hls.Utils.getFirstTagWithName(tags, 'EXTINF');
  3756.     let endTime = 0;
  3757.     let startByte = 0;
  3758.     let endByte = null;
  3760.     if (hlsSegment.partialSegments.length) {
  3761.       this.manifest_.isLowLatency = true;
  3762.     }
  3764.     let syncTime = null;
  3765.     if (!this.config_.hls.ignoreManifestProgramDateTime) {
  3766.       const dateTimeTag =
  3767.           shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-PROGRAM-DATE-TIME');
  3768.       if (dateTimeTag && dateTimeTag.value) {
  3769.         syncTime = shaka.util.TXml.parseDate(dateTimeTag.value);
  3770.         goog.asserts.assert(syncTime != null,
  3771.             'EXT-X-PROGRAM-DATE-TIME format not valid');
  3772.         this.usesProgramDateTime_ = true;
  3773.       }
  3774.     }
  3776.     let status = shaka.media.SegmentReference.Status.AVAILABLE;
  3777.     if (shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-GAP')) {
  3778.       this.manifest_.gapCount++;
  3779.       status = shaka.media.SegmentReference.Status.MISSING;
  3780.     }
  3782.     if (!extinfTag) {
  3783.       if (hlsSegment.partialSegments.length == 0) {
  3784.         // EXTINF tag must be available if the segment has no partial segments.
  3785.         throw new shaka.util.Error(
  3786.             shaka.util.Error.Severity.CRITICAL,
  3787.             shaka.util.Error.Category.MANIFEST,
  3788.             shaka.util.Error.Code.HLS_REQUIRED_TAG_MISSING, 'EXTINF');
  3789.       } else if (!this.lowLatencyMode_) {
  3790.         // Without EXTINF and without low-latency mode, partial segments get
  3791.         // ignored.
  3792.         return null;
  3793.       }
  3794.     }
  3796.     // Create SegmentReferences for the partial segments.
  3797.     let partialSegmentRefs = [];
  3799.     // Optimization for LL-HLS with byterange
  3800.     // More info in https://tinyurl.com/hls-open-byte-range
  3801.     let segmentWithByteRangeOptimization = false;
  3802.     let getUrisOptimization = null;
  3803.     let somePartialSegmentWithGap = false;
  3804.     let isPreloadSegment = false;
  3806.     if (this.lowLatencyMode_ && hlsSegment.partialSegments.length) {
  3807.       const byterangeOptimizationSupport =
  3808.           initSegmentReference && window.ReadableStream &&
  3809.           this.config_.hls.allowLowLatencyByteRangeOptimization;
  3811.       let partialSyncTime = syncTime;
  3812.       for (let i = 0; i < hlsSegment.partialSegments.length; i++) {
  3813.         const item = hlsSegment.partialSegments[i];
  3814.         const pPreviousReference = i == 0 ?
  3815.           previousReference : partialSegmentRefs[partialSegmentRefs.length - 1];
  3816.         const pStartTime = (i == 0) ? startTime : pPreviousReference.endTime;
  3818.         // If DURATION is missing from this partial segment, use the target
  3819.         // partial duration from the top of the playlist, which is a required
  3820.         // attribute for content with partial segments.
  3821.         const pDuration = Number(item.getAttributeValue('DURATION')) ||
  3822.             this.partialTargetDuration_;
  3824.         // If for some reason we have neither an explicit duration, nor a target
  3825.         // partial duration, we should SKIP this partial segment to avoid
  3826.         // duplicating content in the presentation timeline.
  3827.         if (!pDuration) {
  3828.           continue;
  3829.         }
  3831.         const pEndTime = pStartTime + pDuration;
  3833.         let pStartByte = 0;
  3834.         let pEndByte = null;
  3835.         if (item.name == 'EXT-X-PRELOAD-HINT') {
  3836.           // A preload hinted partial segment may have byterange start info.
  3837.           const pByterangeStart = item.getAttributeValue('BYTERANGE-START');
  3838.           pStartByte = pByterangeStart ? Number(pByterangeStart) : 0;
  3839.           // A preload hinted partial segment may have byterange length info.
  3840.           const pByterangeLength = item.getAttributeValue('BYTERANGE-LENGTH');
  3841.           if (pByterangeLength) {
  3842.             pEndByte = pStartByte + Number(pByterangeLength) - 1;
  3843.           } else if (pStartByte) {
  3844.             // If we have a non-zero start byte, but no end byte, follow the
  3845.             // recommendation of https://tinyurl.com/hls-open-byte-range and
  3846.             // set the end byte explicitly to a large integer.
  3847.             pEndByte = Number.MAX_SAFE_INTEGER;
  3848.           }
  3849.         } else {
  3850.           const pByterange = item.getAttributeValue('BYTERANGE');
  3851.           [pStartByte, pEndByte] =
  3852.             this.parseByteRange_(pPreviousReference, pByterange);
  3853.         }
  3854.         const pUri = item.getAttributeValue('URI');
  3855.         if (!pUri) {
  3856.           continue;
  3857.         }
  3859.         let partialStatus = shaka.media.SegmentReference.Status.AVAILABLE;
  3860.         if (item.getAttributeValue('GAP') == 'YES') {
  3861.           this.manifest_.gapCount++;
  3862.           partialStatus = shaka.media.SegmentReference.Status.MISSING;
  3863.           somePartialSegmentWithGap = true;
  3864.         }
  3866.         let uris = null;
  3867.         const getPartialUris = () => {
  3868.           if (uris == null) {
  3869.             goog.asserts.assert(pUri, 'Partial uri should be defined!');
  3870.             uris = shaka.hls.Utils.constructSegmentUris(
  3871.                 getUris(), pUri, variables);
  3872.           }
  3873.           return uris;
  3874.         };
  3876.         if (byterangeOptimizationSupport &&
  3877.             pStartByte >= 0 && pEndByte != null) {
  3878.           getUrisOptimization = getPartialUris;
  3879.           segmentWithByteRangeOptimization = true;
  3880.         }
  3882.         const partial = new shaka.media.SegmentReference(
  3883.             pStartTime,
  3884.             pEndTime,
  3885.             getPartialUris,
  3886.             pStartByte,
  3887.             pEndByte,
  3888.             initSegmentReference,
  3889.             /* timestampOffset= */ 0,
  3890.             /* appendWindowStart= */ 0,
  3891.             /* appendWindowEnd= */ Infinity,
  3892.             /* partialReferences= */ [],
  3893.             /* tilesLayout= */ '',
  3894.             /* tileDuration= */ null,
  3895.             partialSyncTime,
  3896.             partialStatus,
  3897.             aesKey);
  3898.         if (item.name == 'EXT-X-PRELOAD-HINT') {
  3899.           partial.markAsPreload();
  3900.           isPreloadSegment = true;
  3901.         }
  3902.         // The spec doesn't say that we can assume INDEPENDENT=YES for the
  3903.         // first partial segment. It does call the flag "optional", though, and
  3904.         // that cases where there are no such flags on any partial segments, it
  3905.         // is sensible to assume the first one is independent.
  3906.         if (item.getAttributeValue('INDEPENDENT') != 'YES' && i > 0) {
  3907.           partial.markAsNonIndependent();
  3908.         }
  3910.         const pMimeType = getMimeType(pUri);
  3911.         if (pMimeType) {
  3912.           partial.mimeType = pMimeType;
  3913.           if (HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_.has(pMimeType)) {
  3914.             partial.initSegmentReference = null;
  3915.           }
  3916.         }
  3917.         partialSegmentRefs.push(partial);
  3919.         if (partialSyncTime) {
  3920.           partialSyncTime += pDuration;
  3921.         }
  3922.       } // for-loop of hlsSegment.partialSegments
  3923.     }
  3925.     // If the segment has EXTINF tag, set the segment's end time, start byte
  3926.     // and end byte based on the duration and byterange information.
  3927.     // Otherwise, calculate the end time, start / end byte based on its partial
  3928.     // segments.
  3929.     // Note that the sum of partial segments durations may be slightly different
  3930.     // from the parent segment's duration. In this case, use the duration from
  3931.     // the parent segment tag.
  3932.     if (extinfTag) {
  3933.       // The EXTINF tag format is '#EXTINF:<duration>,[<title>]'.
  3934.       // We're interested in the duration part.
  3935.       const extinfValues = extinfTag.value.split(',');
  3936.       const duration = Number(extinfValues[0]);
  3937.       // Skip segments without duration
  3938.       if (duration == 0) {
  3939.         return null;
  3940.       }
  3941.       endTime = startTime + duration;
  3942.     } else if (partialSegmentRefs.length) {
  3943.       endTime = partialSegmentRefs[partialSegmentRefs.length - 1].endTime;
  3944.     } else {
  3945.       // Skip segments without duration and without partial segments
  3946.       return null;
  3947.     }
  3949.     if (segmentWithByteRangeOptimization) {
  3950.       // We cannot optimize segments with gaps, or with a start byte that is
  3951.       // not 0.
  3952.       if (somePartialSegmentWithGap || partialSegmentRefs[0].startByte != 0) {
  3953.         segmentWithByteRangeOptimization = false;
  3954.         getUrisOptimization = null;
  3955.       } else {
  3956.         partialSegmentRefs = [];
  3957.       }
  3958.     }
  3960.     // If the segment has EXT-X-BYTERANGE tag, set the start byte and end byte
  3961.     // base on the byterange information. If segment has no EXT-X-BYTERANGE tag
  3962.     // and has partial segments, set the start byte and end byte base on the
  3963.     // partial segments.
  3964.     const byterangeTag =
  3965.          shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-BYTERANGE');
  3966.     if (byterangeTag) {
  3967.       [startByte, endByte] =
  3968.           this.parseByteRange_(previousReference, byterangeTag.value);
  3969.     } else if (partialSegmentRefs.length) {
  3970.       startByte = partialSegmentRefs[0].startByte;
  3971.       endByte = partialSegmentRefs[partialSegmentRefs.length - 1].endByte;
  3972.     }
  3974.     let tilesLayout = '';
  3975.     let tileDuration = null;
  3976.     if (type == shaka.util.ManifestParserUtils.ContentType.IMAGE) {
  3977.       // By default in HLS the tilesLayout is 1x1
  3978.       tilesLayout = '1x1';
  3979.       const tilesTag =
  3980.           shaka.hls.Utils.getFirstTagWithName(tags, 'EXT-X-TILES');
  3981.       if (tilesTag) {
  3982.         tilesLayout = tilesTag.getRequiredAttrValue('LAYOUT');
  3983.         const duration = tilesTag.getAttributeValue('DURATION');
  3984.         if (duration) {
  3985.           tileDuration = Number(duration);
  3986.         }
  3987.       }
  3988.     }
  3990.     let uris = null;
  3991.     const getSegmentUris = () => {
  3992.       if (getUrisOptimization) {
  3993.         return getUrisOptimization();
  3994.       }
  3995.       if (uris == null) {
  3996.         uris = shaka.hls.Utils.constructSegmentUris(getUris(),
  3997.             hlsSegment.verbatimSegmentUri, variables);
  3998.       }
  3999.       return uris || [];
  4000.     };
  4002.     const allPartialSegments = partialSegmentRefs.length > 0 &&
  4003.         !!hlsSegment.verbatimSegmentUri;
  4005.     const reference = new shaka.media.SegmentReference(
  4006.         startTime,
  4007.         endTime,
  4008.         getSegmentUris,
  4009.         startByte,
  4010.         endByte,
  4011.         initSegmentReference,
  4012.         /* timestampOffset= */ 0,
  4013.         /* appendWindowStart= */ 0,
  4014.         /* appendWindowEnd= */ Infinity,
  4015.         partialSegmentRefs,
  4016.         tilesLayout,
  4017.         tileDuration,
  4018.         syncTime,
  4019.         status,
  4020.         aesKey,
  4021.         allPartialSegments,
  4022.     );
  4024.     const mimeType = getMimeType(hlsSegment.verbatimSegmentUri);
  4025.     if (mimeType) {
  4026.       reference.mimeType = mimeType;
  4027.       if (HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_.has(mimeType)) {
  4028.         reference.initSegmentReference = null;
  4029.       }
  4030.     }
  4032.     if (segmentWithByteRangeOptimization) {
  4033.       this.lowLatencyByterangeOptimization_ = true;
  4034.       reference.markAsByterangeOptimization();
  4036.       if (isPreloadSegment) {
  4037.         reference.markAsPreload();
  4038.       }
  4039.     }
  4041.     return reference;
  4042.   }
  4045.   /**
  4046.    * Parse the startByte and endByte.
  4047.    * @param {shaka.media.SegmentReference} previousReference
  4048.    * @param {?string} byterange
  4049.    * @return {!Array<number>} An array with the start byte and end byte.
  4050.    * @private
  4051.    */
  4052.   parseByteRange_(previousReference, byterange) {
  4053.     let startByte = 0;
  4054.     let endByte = null;
  4055.     // If BYTERANGE is not specified, the segment consists of the entire
  4056.     // resource.
  4057.     if (byterange) {
  4058.       const blocks = byterange.split('@');
  4059.       const byteLength = Number(blocks[0]);
  4060.       if (blocks[1]) {
  4061.         startByte = Number(blocks[1]);
  4062.       } else {
  4063.         goog.asserts.assert(previousReference,
  4064.             'Cannot refer back to previous HLS segment!');
  4065.         startByte = previousReference.endByte + 1;
  4066.       }
  4067.       endByte = startByte + byteLength - 1;
  4068.     }
  4069.     return [startByte, endByte];
  4070.   }
  4072.   /**
  4073.    * @param {!Array<!shaka.hls.Tag>} tags
  4074.    * @param {string} contentType
  4075.    * @param {!Map<string, string>} variables
  4076.    * @param {function(): !Array<string>} getUris
  4077.    * @private
  4078.    */
  4079.   processDateRangeTags_(tags, contentType, variables, getUris) {
  4080.     const ContentType = shaka.util.ManifestParserUtils.ContentType;
  4081.     if (contentType != ContentType.VIDEO && contentType != ContentType.AUDIO) {
  4082.       // DATE-RANGE should only appear in AUDIO or VIDEO playlists.
  4083.       // We ignore those that appear in other playlists.
  4084.       return;
  4085.     }
  4086.     const Utils = shaka.hls.Utils;
  4087.     const initialProgramDateTime =
  4088.         this.presentationTimeline_.getInitialProgramDateTime();
  4089.     if (!initialProgramDateTime ||
  4090.         this.ignoreManifestProgramDateTimeFor_(contentType)) {
  4091.       return;
  4092.     }
  4093.     let dateRangeTags =
  4094.         shaka.hls.Utils.filterTagsByName(tags, 'EXT-X-DATERANGE');
  4095.     dateRangeTags = dateRangeTags.filter((tag) => {
  4096.       return tag.getAttribute('START-DATE') != null;
  4097.     }).sort((a, b) => {
  4098.       const aStartDateValue = a.getRequiredAttrValue('START-DATE');
  4099.       const bStartDateValue = b.getRequiredAttrValue('START-DATE');
  4100.       if (aStartDateValue < bStartDateValue) {
  4101.         return -1;
  4102.       }
  4103.       if (aStartDateValue > bStartDateValue) {
  4104.         return 1;
  4105.       }
  4106.       return 0;
  4107.     });
  4108.     for (let i = 0; i < dateRangeTags.length; i++) {
  4109.       const tag = dateRangeTags[i];
  4110.       try {
  4111.         const startDateValue = tag.getRequiredAttrValue('START-DATE');
  4112.         const startDate = shaka.util.TXml.parseDate(startDateValue);
  4113.         if (isNaN(startDate)) {
  4114.           // Invalid START-DATE
  4115.           continue;
  4116.         }
  4117.         goog.asserts.assert(startDate != null,
  4118.             'Start date should not be null!');
  4119.         const startTime = Math.max(0, startDate - initialProgramDateTime);
  4121.         let endTime = null;
  4122.         const endDateValue = tag.getAttributeValue('END-DATE');
  4123.         if (endDateValue) {
  4124.           const endDate = shaka.util.TXml.parseDate(endDateValue);
  4125.           if (!isNaN(endDate)) {
  4126.             goog.asserts.assert(endDate != null,
  4127.                 'End date should not be null!');
  4128.             endTime = endDate - initialProgramDateTime;
  4129.             if (endTime < 0) {
  4130.               // Date range in the past
  4131.               continue;
  4132.             }
  4133.           }
  4134.         }
  4135.         if (endTime == null) {
  4136.           const durationValue = tag.getAttributeValue('DURATION') ||
  4137.               tag.getAttributeValue('PLANNED-DURATION');
  4138.           if (durationValue) {
  4139.             const duration = parseFloat(durationValue);
  4140.             if (!isNaN(duration)) {
  4141.               endTime = startTime + duration;
  4142.             }
  4143.             const realEndTime = startDate - initialProgramDateTime + duration;
  4144.             if (realEndTime < 0) {
  4145.               // Date range in the past
  4146.               continue;
  4147.             }
  4148.           }
  4149.         }
  4150.         const type =
  4151.             tag.getAttributeValue('CLASS') || 'com.apple.quicktime.HLS';
  4153.         const endOnNext = tag.getAttributeValue('END-ON-NEXT') == 'YES';
  4154.         if (endTime == null && endOnNext) {
  4155.           for (let j = i + 1; j < dateRangeTags.length; j++) {
  4156.             const otherDateRangeType =
  4157.                 dateRangeTags[j].getAttributeValue('CLASS') ||
  4158.                 'com.apple.quicktime.HLS';
  4159.             if (type != otherDateRangeType) {
  4160.               continue;
  4161.             }
  4162.             const otherDateRangeStartDateValue =
  4163.                 dateRangeTags[j].getRequiredAttrValue('START-DATE');
  4164.             const otherDateRangeStartDate =
  4165.                 shaka.util.TXml.parseDate(otherDateRangeStartDateValue);
  4166.             if (isNaN(otherDateRangeStartDate)) {
  4167.               // Invalid START-DATE
  4168.               continue;
  4169.             }
  4170.             if (otherDateRangeStartDate &&
  4171.                 otherDateRangeStartDate > startDate) {
  4172.               endTime = Math.max(0,
  4173.                   otherDateRangeStartDate - initialProgramDateTime);
  4174.               break;
  4175.             }
  4176.           }
  4177.           if (endTime == null) {
  4178.             // Since we cannot know when it ends, we omit it for now and in the
  4179.             // future with an update we will be able to have more information.
  4180.             continue;
  4181.           }
  4182.         }
  4184.         // Exclude these attributes from the metadata since they already go into
  4185.         // other fields (eg: startTime or endTime) or are not necessary..
  4186.         const excludedAttributes = [
  4187.           'CLASS',
  4188.           'START-DATE',
  4189.           'END-DATE',
  4190.           'DURATION',
  4191.           'END-ON-NEXT',
  4192.         ];
  4194.         /* @type {!Array<shaka.extern.MetadataFrame>} */
  4195.         const values = [];
  4196.         for (const attribute of tag.attributes) {
  4197.           if (excludedAttributes.includes(attribute.name)) {
  4198.             continue;
  4199.           }
  4200.           let data = Utils.variableSubstitution(attribute.value, variables);
  4201.           if (attribute.name == 'X-ASSET-URI' ||
  4202.               attribute.name == 'X-ASSET-LIST') {
  4203.             data = Utils.constructSegmentUris(
  4204.                 getUris(), attribute.value, variables)[0];
  4205.           }
  4206.           const metadataFrame = {
  4207.             key: attribute.name,
  4208.             description: '',
  4209.             data,
  4210.             mimeType: null,
  4211.             pictureType: null,
  4212.           };
  4213.           values.push(metadataFrame);
  4214.         }
  4216.         // ID is always required. So we need more than 1 value.
  4217.         if (values.length > 1) {
  4218.           this.playerInterface_.onMetadata(type, startTime, endTime, values);
  4219.         }
  4220.       } catch (e) {
  4221.         shaka.log.warning('Ignoring DATERANGE with errors', tag.toString());
  4222.       }
  4223.     }
  4224.   }
  4226.   /**
  4227.    * Parses shaka.hls.Segment objects into shaka.media.SegmentReferences and
  4228.    * get the bandwidth necessary for this segments If it's defined in the
  4229.    * playlist.
  4230.    *
  4231.    * @param {!shaka.hls.Playlist} playlist
  4232.    * @param {!Map<number, number>} mediaSequenceToStartTime
  4233.    * @param {!Map<string, string>} variables
  4234.    * @param {function(): !Array<string>} getUris
  4235.    * @param {string} type
  4236.    * @return {{segments: !Array<!shaka.media.SegmentReference>,
  4237.    *          bandwidth: (number|undefined)}}
  4238.    * @private
  4239.    */
  4240.   createSegments_(playlist, mediaSequenceToStartTime, variables,
  4241.       getUris, type) {
  4242.     /** @type {Array<!shaka.hls.Segment>} */
  4243.     const hlsSegments = playlist.segments;
  4244.     goog.asserts.assert(hlsSegments.length, 'Playlist should have segments!');
  4246.     /** @type {shaka.media.InitSegmentReference} */
  4247.     let initSegmentRef;
  4249.     /** @type {shaka.extern.aesKey|undefined} */
  4250.     let aesKey = undefined;
  4252.     let discontinuitySequence = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4253.         playlist.tags, 'EXT-X-DISCONTINUITY-SEQUENCE', -1);
  4254.     const mediaSequenceNumber = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4255.         playlist.tags, 'EXT-X-MEDIA-SEQUENCE', 0);
  4256.     const skipTag = shaka.hls.Utils.getFirstTagWithName(
  4257.         playlist.tags, 'EXT-X-SKIP');
  4258.     const skippedSegments =
  4259.         skipTag ? Number(skipTag.getAttributeValue('SKIPPED-SEGMENTS')) : 0;
  4260.     let position = mediaSequenceNumber + skippedSegments;
  4261.     let firstStartTime = 0;
  4263.     // For live stream, use the cached value in the mediaSequenceToStartTime
  4264.     // map if available.
  4265.     if (this.isLive_() && mediaSequenceToStartTime.has(position)) {
  4266.       firstStartTime = mediaSequenceToStartTime.get(position);
  4267.     }
  4268.     // This is for recovering from disconnects.
  4269.     if (firstStartTime === 0 &&
  4270.         this.presentationType_ == shaka.hls.HlsParser.PresentationType_.LIVE &&
  4271.         mediaSequenceToStartTime.size > 0 &&
  4272.         !mediaSequenceToStartTime.has(position) &&
  4273.         this.presentationTimeline_.getPresentationStartTime() != null) {
  4274.       firstStartTime = this.presentationTimeline_.getSegmentAvailabilityStart();
  4275.     }
  4277.     /** @type {!Array<!shaka.media.SegmentReference>} */
  4278.     const references = [];
  4280.     let previousReference = null;
  4282.     /** @type {!Array<{bitrate: number, duration: number}>} */
  4283.     const bitrates = [];
  4285.     for (let i = 0; i < hlsSegments.length; i++) {
  4286.       const item = hlsSegments[i];
  4287.       const startTime =
  4288.           (i == 0) ? firstStartTime : previousReference.endTime;
  4289.       position = mediaSequenceNumber + skippedSegments + i;
  4291.       const discontinuityTag = shaka.hls.Utils.getFirstTagWithName(
  4292.           item.tags, 'EXT-X-DISCONTINUITY');
  4293.       if (discontinuityTag) {
  4294.         discontinuitySequence++;
  4296.         if (previousReference && previousReference.initSegmentReference) {
  4297.           previousReference.initSegmentReference.boundaryEnd = startTime;
  4298.         }
  4299.       }
  4301.       // Apply new AES tags as you see them, keeping a running total.
  4302.       for (const drmTag of item.tags) {
  4303.         if (drmTag.name == 'EXT-X-KEY') {
  4304.           if (this.isAesMethod_(drmTag.getRequiredAttrValue('METHOD'))) {
  4305.             aesKey =
  4306.                 this.parseAESDrmTag_(drmTag, playlist, getUris, variables);
  4307.           } else {
  4308.             aesKey = undefined;
  4309.           }
  4310.         }
  4311.       }
  4313.       mediaSequenceToStartTime.set(position, startTime);
  4315.       initSegmentRef = this.getInitSegmentReference_(playlist,
  4316.           item.tags, getUris, variables);
  4318.       const reference = this.createSegmentReference_(
  4319.           initSegmentRef,
  4320.           previousReference,
  4321.           item,
  4322.           startTime,
  4323.           variables,
  4324.           playlist,
  4325.           type,
  4326.           getUris,
  4327.           aesKey);
  4329.       if (reference) {
  4330.         const bitrate = shaka.hls.Utils.getFirstTagWithNameAsNumber(
  4331.             item.tags, 'EXT-X-BITRATE');
  4332.         if (bitrate) {
  4333.           bitrates.push({
  4334.             bitrate,
  4335.             duration: reference.endTime - reference.startTime,
  4336.           });
  4337.         } else if (bitrates.length) {
  4338.           // It applies to every segment between it and the next EXT-X-BITRATE,
  4339.           // so we use the latest bitrate value
  4340.           const prevBitrate = bitrates.pop();
  4341.           prevBitrate.duration += reference.endTime - reference.startTime;
  4342.           bitrates.push(prevBitrate);
  4343.         }
  4345.         previousReference = reference;
  4346.         reference.discontinuitySequence = discontinuitySequence;
  4348.         if (this.ignoreManifestProgramDateTimeFor_(type) &&
  4349.             this.minSequenceNumber_ != null &&
  4350.             position < this.minSequenceNumber_) {
  4351.           // This segment is ignored as part of our fallback synchronization
  4352.           // method.
  4353.         } else {
  4354.           references.push(reference);
  4355.         }
  4356.       }
  4357.     }
  4359.     let bandwidth = undefined;
  4360.     if (bitrates.length) {
  4361.       const duration = bitrates.reduce((sum, value) => {
  4362.         return sum + value.duration;
  4363.       }, 0);
  4364.       bandwidth = Math.round(bitrates.reduce((sum, value) => {
  4365.         return sum + value.bitrate * value.duration;
  4366.       }, 0) / duration * 1000);
  4367.     }
  4369.     // If some segments have sync times, but not all, extrapolate the sync
  4370.     // times of the ones with none.
  4371.     const someSyncTime = references.some((ref) => ref.syncTime != null);
  4372.     if (someSyncTime) {
  4373.       for (let i = 0; i < references.length; i++) {
  4374.         const reference = references[i];
  4375.         if (reference.syncTime != null) {
  4376.           // No need to extrapolate.
  4377.           continue;
  4378.         }
  4379.         // Find the nearest segment with syncTime, in either direction.
  4380.         // This looks forward and backward simultaneously, keeping track of what
  4381.         // to offset the syncTime it finds by as it goes.
  4382.         let forwardAdd = 0;
  4383.         let forwardI = i;
  4384.         /**
  4385.          * Look forwards one reference at a time, summing all durations as we
  4386.          * go, until we find a reference with a syncTime to use as a basis.
  4387.          * This DOES count the original reference, but DOESN'T count the first
  4388.          * reference with a syncTime (as we approach it from behind).
  4389.          * @return {?number}
  4390.          */
  4391.         const lookForward = () => {
  4392.           const other = references[forwardI];
  4393.           if (other) {
  4394.             if (other.syncTime != null) {
  4395.               return other.syncTime + forwardAdd;
  4396.             }
  4397.             forwardAdd -= other.endTime - other.startTime;
  4398.             forwardI += 1;
  4399.           }
  4400.           return null;
  4401.         };
  4402.         let backwardAdd = 0;
  4403.         let backwardI = i;
  4404.         /**
  4405.          * Look backwards one reference at a time, summing all durations as we
  4406.          * go, until we find a reference with a syncTime to use as a basis.
  4407.          * This DOESN'T count the original reference, but DOES count the first
  4408.          * reference with a syncTime (as we approach it from ahead).
  4409.          * @return {?number}
  4410.          */
  4411.         const lookBackward = () => {
  4412.           const other = references[backwardI];
  4413.           if (other) {
  4414.             if (other != reference) {
  4415.               backwardAdd += other.endTime - other.startTime;
  4416.             }
  4417.             if (other.syncTime != null) {
  4418.               return other.syncTime + backwardAdd;
  4419.             }
  4420.             backwardI -= 1;
  4421.           }
  4422.           return null;
  4423.         };
  4424.         while (reference.syncTime == null) {
  4425.           reference.syncTime = lookBackward();
  4426.           if (reference.syncTime == null) {
  4427.             reference.syncTime = lookForward();
  4428.           }
  4429.         }
  4430.       }
  4431.     }
  4433.     // Split the sync times properly among partial segments.
  4434.     if (someSyncTime) {
  4435.       for (const reference of references) {
  4436.         let syncTime = reference.syncTime;
  4437.         for (const partial of reference.partialReferences) {
  4438.           partial.syncTime = syncTime;
  4439.           syncTime += partial.endTime - partial.startTime;
  4440.         }
  4441.       }
  4442.     }
  4444.     // lowestSyncTime is a value from a previous playlist update.  Use it to
  4445.     // set reference start times.  If this is the first playlist parse, we will
  4446.     // skip this step, and wait until we have sync time across stream types.
  4447.     const lowestSyncTime = this.lowestSyncTime_;
  4448.     if (someSyncTime && lowestSyncTime != Infinity) {
  4449.       if (!this.ignoreManifestProgramDateTimeFor_(type)) {
  4450.         for (const reference of references) {
  4451.           reference.syncAgainst(lowestSyncTime);
  4452.         }
  4453.       }
  4454.     }
  4456.     return {
  4457.       segments: references,
  4458.       bandwidth,
  4459.     };
  4460.   }
  4462.   /**
  4463.    * Attempts to guess stream's mime type based on content type and URI.
  4464.    *
  4465.    * @param {string} contentType
  4466.    * @param {string} codecs
  4467.    * @return {?string}
  4468.    * @private
  4469.    */
  4470.   guessMimeTypeBeforeLoading_(contentType, codecs) {
  4471.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  4472.       if (codecs == 'vtt' || codecs == 'wvtt') {
  4473.         // If codecs is 'vtt', it's WebVTT.
  4474.         return 'text/vtt';
  4475.       } else if (codecs && codecs !== '') {
  4476.         // Otherwise, assume MP4-embedded text, since text-based formats tend
  4477.         // not to have a codecs string at all.
  4478.         return 'application/mp4';
  4479.       }
  4480.     }
  4482.     if (contentType == shaka.util.ManifestParserUtils.ContentType.IMAGE) {
  4483.       if (!codecs || codecs == 'jpeg') {
  4484.         return 'image/jpeg';
  4485.       }
  4486.     }
  4488.     if (contentType == shaka.util.ManifestParserUtils.ContentType.AUDIO) {
  4489.       // See: https://bugs.chromium.org/p/chromium/issues/detail?id=489520
  4490.       if (codecs == 'mp4a.40.34') {
  4491.         return 'audio/mpeg';
  4492.       }
  4493.     }
  4495.     if (codecs == 'mjpg') {
  4496.       return 'application/mp4';
  4497.     }
  4499.     // Not enough information to guess from the content type and codecs.
  4500.     return null;
  4501.   }
  4503.   /**
  4504.    * Get a fallback mime type for the content. Used if all the better methods
  4505.    * for determining the mime type have failed.
  4506.    *
  4507.    * @param {string} contentType
  4508.    * @return {string}
  4509.    * @private
  4510.    */
  4511.   guessMimeTypeFallback_(contentType) {
  4512.     if (contentType == shaka.util.ManifestParserUtils.ContentType.TEXT) {
  4513.       // If there was no codecs string and no content-type, assume HLS text
  4514.       // streams are WebVTT.
  4515.       return 'text/vtt';
  4516.     }
  4517.     // If the HLS content is lacking in both MIME type metadata and
  4518.     // segment file extensions, we fall back to assuming it's MP4.
  4519.     const map =
  4520.         shaka.hls.HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_.get(contentType);
  4521.     return map.get('mp4');
  4522.   }
  4524.   /**
  4525.    * @param {!Array<!shaka.media.SegmentReference>} segments
  4526.    * @return {{segment: !shaka.media.SegmentReference, segmentIndex: number}}
  4527.    * @private
  4528.    */
  4529.   getAvailableSegment_(segments) {
  4530.     goog.asserts.assert(segments.length, 'Should have segments!');
  4532.     // If you wait long enough, requesting the first segment can fail
  4533.     // because it has fallen off the left edge of DVR, so to be safer,
  4534.     // let's request the middle segment.
  4535.     let segmentIndex = this.isLive_() ?
  4536.         Math.trunc((segments.length - 1) / 2) : 0;
  4537.     let segment = segments[segmentIndex];
  4538.     while (segment.getStatus() == shaka.media.SegmentReference.Status.MISSING &&
  4539.         (segmentIndex + 1) < segments.length) {
  4540.       segmentIndex ++;
  4541.       segment = segments[segmentIndex];
  4542.     }
  4543.     return {segment, segmentIndex};
  4544.   }
  4546.   /**
  4547.    * Attempts to guess stream's mime type.
  4548.    *
  4549.    * @param {string} contentType
  4550.    * @param {string} codecs
  4551.    * @param {!Array<!shaka.media.SegmentReference>} segments
  4552.    * @return {!Promise<string>}
  4553.    * @private
  4554.    */
  4555.   async guessMimeType_(contentType, codecs, segments) {
  4556.     const HlsParser = shaka.hls.HlsParser;
  4557.     const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  4559.     const {segment} = this.getAvailableSegment_(segments);
  4561.     if (segment.status == shaka.media.SegmentReference.Status.MISSING) {
  4562.       return this.guessMimeTypeFallback_(contentType);
  4563.     }
  4565.     const segmentUris = segment.getUris();
  4567.     const parsedUri = new goog.Uri(segmentUris[0]);
  4568.     const extension = parsedUri.getPath().split('.').pop();
  4569.     const map = HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_.get(contentType);
  4571.     let mimeType = map.get(extension);
  4572.     if (mimeType) {
  4573.       return mimeType;
  4574.     }
  4576.     mimeType = HlsParser.RAW_FORMATS_TO_MIME_TYPES_.get(extension);
  4577.     if (mimeType) {
  4578.       return mimeType;
  4579.     }
  4581.     // The extension map didn't work, so guess based on codecs.
  4582.     mimeType = this.guessMimeTypeBeforeLoading_(contentType, codecs);
  4583.     if (mimeType) {
  4584.       return mimeType;
  4585.     }
  4587.     // If unable to guess mime type, request a segment and try getting it
  4588.     // from the response.
  4589.     let contentMimeType;
  4590.     const type = shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_SEGMENT;
  4591.     const headRequest = shaka.net.NetworkingEngine.makeRequest(
  4592.         segmentUris, this.config_.retryParameters);
  4593.     let response;
  4594.     try {
  4595.       headRequest.method = 'HEAD';
  4596.       response = await this.makeNetworkRequest_(
  4597.           headRequest, requestType, {type}).promise;
  4599.       contentMimeType = response.headers['content-type'];
  4600.     } catch (error) {
  4601.       if (error &&
  4602.         (error.code == shaka.util.Error.Code.HTTP_ERROR ||
  4603.          error.code == shaka.util.Error.Code.BAD_HTTP_STATUS)) {
  4604.         headRequest.method = 'GET';
  4605.         if (this.config_.hls.allowRangeRequestsToGuessMimeType) {
  4606.           // Only requesting first byte
  4607.           headRequest.headers['Range'] = 'bytes=0-0';
  4608.         }
  4609.         response = await this.makeNetworkRequest_(
  4610.             headRequest, requestType, {type}).promise;
  4612.         contentMimeType = response.headers['content-type'];
  4613.       }
  4614.     }
  4616.     if (contentMimeType) {
  4617.       // Split the MIME type in case the server sent additional parameters.
  4618.       mimeType = contentMimeType.toLowerCase().split(';')[0];
  4619.       if (mimeType == 'application/octet-stream') {
  4620.         if (!response.data.byteLength) {
  4621.           headRequest.method = 'GET';
  4622.           response = await this.makeNetworkRequest_(
  4623.               headRequest, requestType, {type}).promise;
  4624.         }
  4625.         if (shaka.util.TsParser.probe(
  4626.             shaka.util.BufferUtils.toUint8(response.data))) {
  4627.           mimeType = 'video/mp2t';
  4628.         }
  4629.       }
  4630.       if (mimeType != 'application/octet-stream') {
  4631.         return mimeType;
  4632.       }
  4633.     }
  4635.     return this.guessMimeTypeFallback_(contentType);
  4636.   }
  4638.   /**
  4639.    * Returns a tag with a given name.
  4640.    * Throws an error if tag was not found.
  4641.    *
  4642.    * @param {!Array<shaka.hls.Tag>} tags
  4643.    * @param {string} tagName
  4644.    * @return {!shaka.hls.Tag}
  4645.    * @private
  4646.    */
  4647.   getRequiredTag_(tags, tagName) {
  4648.     const tag = shaka.hls.Utils.getFirstTagWithName(tags, tagName);
  4649.     if (!tag) {
  4650.       throw new shaka.util.Error(
  4651.           shaka.util.Error.Severity.CRITICAL,
  4652.           shaka.util.Error.Category.MANIFEST,
  4653.           shaka.util.Error.Code.HLS_REQUIRED_TAG_MISSING, tagName);
  4654.     }
  4656.     return tag;
  4657.   }
  4659.   /**
  4660.    * @param {shaka.extern.Stream} stream
  4661.    * @param {?string} width
  4662.    * @param {?string} height
  4663.    * @param {?string} frameRate
  4664.    * @param {?string} videoRange
  4665.    * @param {?string} videoLayout
  4666.    * @param {?string} colorGamut
  4667.    * @private
  4668.    */
  4669.   addVideoAttributes_(stream, width, height, frameRate, videoRange,
  4670.       videoLayout, colorGamut) {
  4671.     if (stream) {
  4672.       stream.width = Number(width) || undefined;
  4673.       stream.height = Number(height) || undefined;
  4674.       stream.frameRate = Number(frameRate) || undefined;
  4675.       stream.hdr = videoRange || undefined;
  4676.       stream.videoLayout = videoLayout || undefined;
  4677.       stream.colorGamut = colorGamut || undefined;
  4678.     }
  4679.   }
  4681.   /**
  4682.    * Makes a network request for the manifest and returns a Promise
  4683.    * with the resulting data.
  4684.    *
  4685.    * @param {!Array<string>} uris
  4686.    * @param {boolean=} isPlaylist
  4687.    * @return {!shaka.net.NetworkingEngine.PendingRequest}
  4688.    * @private
  4689.    */
  4690.   requestManifest_(uris, isPlaylist) {
  4691.     const requestType = shaka.net.NetworkingEngine.RequestType.MANIFEST;
  4693.     const request = shaka.net.NetworkingEngine.makeRequest(
  4694.         uris, this.config_.retryParameters);
  4696.     const type = isPlaylist ?
  4697.         shaka.net.NetworkingEngine.AdvancedRequestType.MEDIA_PLAYLIST :
  4698.         shaka.net.NetworkingEngine.AdvancedRequestType.MASTER_PLAYLIST;
  4699.     return this.makeNetworkRequest_(request, requestType, {type});
  4700.   }
  4702.   /**
  4703.    * Called when the update timer ticks. Because parsing a manifest is async,
  4704.    * this method is async. To work with this, this method will schedule the next
  4705.    * update when it finished instead of using a repeating-start.
  4706.    *
  4707.    * @return {!Promise}
  4708.    * @private
  4709.    */
  4710.   async onUpdate_() {
  4711.     shaka.log.info('Updating manifest...');
  4713.     goog.asserts.assert(
  4714.         this.getUpdatePlaylistDelay_() > 0,
  4715.         'We should only call |onUpdate_| when we are suppose to be updating.');
  4717.     // Detect a call to stop()
  4718.     if (!this.playerInterface_) {
  4719.       return;
  4720.     }
  4722.     try {
  4723.       const startTime = Date.now();
  4724.       await this.update();
  4726.       // Keep track of how long the longest manifest update took.
  4727.       const endTime = Date.now();
  4729.       // This may have converted to VOD, in which case we stop updating.
  4730.       if (this.isLive_()) {
  4731.         const updateDuration = (endTime - startTime) / 1000.0;
  4732.         this.averageUpdateDuration_.sample(1, updateDuration);
  4733.         const delay = this.config_.updatePeriod > 0 ?
  4734.             this.config_.updatePeriod : this.getUpdatePlaylistDelay_();
  4735.         const finalDelay = Math.max(0,
  4736.             delay - this.averageUpdateDuration_.getEstimate());
  4737.         this.updatePlaylistTimer_.tickAfter(/* seconds= */ finalDelay);
  4738.       }
  4739.     } catch (error) {
  4740.       // Detect a call to stop() during this.update()
  4741.       if (!this.playerInterface_) {
  4742.         return;
  4743.       }
  4745.       goog.asserts.assert(error instanceof shaka.util.Error,
  4746.           'Should only receive a Shaka error');
  4748.       if (this.config_.raiseFatalErrorOnManifestUpdateRequestFailure) {
  4749.         this.playerInterface_.onError(error);
  4750.         return;
  4751.       }
  4753.       // We will retry updating, so override the severity of the error.
  4754.       error.severity = shaka.util.Error.Severity.RECOVERABLE;
  4755.       this.playerInterface_.onError(error);
  4757.       // Try again very soon.
  4758.       this.updatePlaylistTimer_.tickAfter(/* seconds= */ 0.1);
  4759.     }
  4761.     // Detect a call to stop()
  4762.     if (!this.playerInterface_) {
  4763.       return;
  4764.     }
  4766.     this.playerInterface_.onManifestUpdated();
  4767.   }
  4770.   /**
  4771.    * @return {boolean}
  4772.    * @private
  4773.    */
  4774.   isLive_() {
  4775.     const PresentationType = shaka.hls.HlsParser.PresentationType_;
  4776.     return this.presentationType_ != PresentationType.VOD;
  4777.   }
  4780.   /**
  4781.    * @return {number}
  4782.    * @private
  4783.    */
  4784.   getUpdatePlaylistDelay_() {
  4785.     // The HLS spec (RFC 8216) states in 6.3.4:
  4786.     // "the client MUST wait for at least the target duration before
  4787.     // attempting to reload the Playlist file again".
  4788.     // For LL-HLS, the server must add a new partial segment to the Playlist
  4789.     // every part target duration.
  4790.     return this.lastTargetDuration_;
  4791.   }
  4794.   /**
  4795.    * @param {shaka.hls.HlsParser.PresentationType_} type
  4796.    * @private
  4797.    */
  4798.   setPresentationType_(type) {
  4799.     this.presentationType_ = type;
  4801.     if (this.presentationTimeline_) {
  4802.       this.presentationTimeline_.setStatic(!this.isLive_());
  4803.     }
  4805.     // If this manifest is not for live content, then we have no reason to
  4806.     // update it.
  4807.     if (!this.isLive_()) {
  4808.       this.updatePlaylistTimer_.stop();
  4809.     }
  4810.   }
  4813.   /**
  4814.    * Create a networking request. This will manage the request using the
  4815.    * parser's operation manager. If the parser has already been stopped, the
  4816.    * request will not be made.
  4817.    *
  4818.    * @param {shaka.extern.Request} request
  4819.    * @param {shaka.net.NetworkingEngine.RequestType} type
  4820.    * @param {shaka.extern.RequestContext=} context
  4821.    * @return {!shaka.net.NetworkingEngine.PendingRequest}
  4822.    * @private
  4823.    */
  4824.   makeNetworkRequest_(request, type, context) {
  4825.     if (!this.operationManager_) {
  4826.       throw new shaka.util.Error(
  4827.           shaka.util.Error.Severity.CRITICAL,
  4828.           shaka.util.Error.Category.PLAYER,
  4829.           shaka.util.Error.Code.OPERATION_ABORTED);
  4830.     }
  4832.     if (!context) {
  4833.       context = {};
  4834.     }
  4835.     context.isPreload = this.isPreloadFn_();
  4836.     const op = this.playerInterface_.networkingEngine.request(
  4837.         type, request, context);
  4838.     this.operationManager_.manage(op);
  4840.     return op;
  4841.   }
  4843.   /**
  4844.    * @param {string} method
  4845.    * @return {boolean}
  4846.    * @private
  4847.    */
  4848.   isAesMethod_(method) {
  4849.     return method == 'AES-128' ||
  4850.         method == 'AES-256' ||
  4851.         method == 'AES-256-CTR';
  4852.   }
  4854.   /**
  4855.    * @param {!shaka.hls.Tag} drmTag
  4856.    * @param {string} mimeType
  4857.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  4858.    * @return {!Promise<?shaka.extern.DrmInfo>}
  4859.    * @private
  4860.    */
  4861.   async fairplayDrmParser_(drmTag, mimeType, initSegmentRef) {
  4862.     if (mimeType == 'video/mp2t') {
  4863.       throw new shaka.util.Error(
  4864.           shaka.util.Error.Severity.CRITICAL,
  4865.           shaka.util.Error.Category.MANIFEST,
  4866.           shaka.util.Error.Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
  4867.     }
  4869.     if (shaka.drm.DrmUtils.isMediaKeysPolyfilled('apple')) {
  4870.       throw new shaka.util.Error(
  4871.           shaka.util.Error.Severity.CRITICAL,
  4872.           shaka.util.Error.Category.MANIFEST,
  4873.           shaka.util.Error.Code
  4874.               .HLS_MSE_ENCRYPTED_LEGACY_APPLE_MEDIA_KEYS_NOT_SUPPORTED);
  4875.     }
  4877.     const method = drmTag.getRequiredAttrValue('METHOD');
  4878.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4879.     if (!VALID_METHODS.includes(method)) {
  4880.       shaka.log.error('FairPlay in HLS is only supported with [',
  4881.           VALID_METHODS.join(', '), '], not', method);
  4882.       return null;
  4883.     }
  4885.     let encryptionScheme = 'cenc';
  4886.     if (method == 'SAMPLE-AES') {
  4887.       // It should be 'cbcs-1-9' but Safari doesn't support it.
  4888.       // See: https://github.com/WebKit/WebKit/blob/main/Source/WebCore/Modules/encryptedmedia/MediaKeyEncryptionScheme.idl
  4889.       encryptionScheme = 'cbcs';
  4890.     }
  4892.     const uri = drmTag.getRequiredAttrValue('URI');
  4894.     /*
  4895.      * Even if we're not able to construct initData through the HLS tag, adding
  4896.      * a DRMInfo will allow DRM Engine to request a media key system access
  4897.      * with the correct keySystem and initDataType
  4898.      */
  4899.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4900.         'com.apple.fps', encryptionScheme, [
  4901.           {initDataType: 'sinf', initData: new Uint8Array(0), keyId: null},
  4902.         ], uri);
  4904.     let keyId = shaka.drm.FairPlay.defaultGetKeyId(uri);
  4905.     if (!keyId && initSegmentRef) {
  4906.       keyId = await this.getKeyIdFromInitSegment_(initSegmentRef);
  4907.     }
  4908.     if (keyId) {
  4909.       drmInfo.keyIds.add(keyId);
  4910.     }
  4912.     return drmInfo;
  4913.   }
  4915.   /**
  4916.    * @param {!shaka.hls.Tag} drmTag
  4917.    * @param {string} mimeType
  4918.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  4919.    * @return {!Promise<?shaka.extern.DrmInfo>}
  4920.    * @private
  4921.    */
  4922.   widevineDrmParser_(drmTag, mimeType, initSegmentRef) {
  4923.     const method = drmTag.getRequiredAttrValue('METHOD');
  4924.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4925.     if (!VALID_METHODS.includes(method)) {
  4926.       shaka.log.error('Widevine in HLS is only supported with [',
  4927.           VALID_METHODS.join(', '), '], not', method);
  4928.       return Promise.resolve(null);
  4929.     }
  4931.     let encryptionScheme = 'cenc';
  4932.     if (method == 'SAMPLE-AES') {
  4933.       encryptionScheme = 'cbcs';
  4934.     }
  4936.     const uri = drmTag.getRequiredAttrValue('URI');
  4937.     const parsedData = shaka.net.DataUriPlugin.parseRaw(uri.split('?')[0]);
  4939.     // The data encoded in the URI is a PSSH box to be used as init data.
  4940.     const pssh = shaka.util.BufferUtils.toUint8(parsedData.data);
  4941.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4942.         'com.widevine.alpha', encryptionScheme, [
  4943.           {initDataType: 'cenc', initData: pssh},
  4944.         ]);
  4946.     const keyId = drmTag.getAttributeValue('KEYID');
  4947.     if (keyId) {
  4948.       const keyIdLowerCase = keyId.toLowerCase();
  4949.       // This value should begin with '0x':
  4950.       goog.asserts.assert(
  4951.           keyIdLowerCase.startsWith('0x'), 'Incorrect KEYID format!');
  4952.       // But the output should not contain the '0x':
  4953.       drmInfo.keyIds.add(keyIdLowerCase.substr(2));
  4954.     }
  4955.     return Promise.resolve(drmInfo);
  4956.   }
  4958.   /**
  4959.    * See: https://docs.microsoft.com/en-us/playready/packaging/mp4-based-formats-supported-by-playready-clients?tabs=case4
  4960.    *
  4961.    * @param {!shaka.hls.Tag} drmTag
  4962.    * @param {string} mimeType
  4963.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  4964.    * @return {!Promise<?shaka.extern.DrmInfo>}
  4965.    * @private
  4966.    */
  4967.   playreadyDrmParser_(drmTag, mimeType, initSegmentRef) {
  4968.     const method = drmTag.getRequiredAttrValue('METHOD');
  4969.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  4970.     if (!VALID_METHODS.includes(method)) {
  4971.       shaka.log.error('PlayReady in HLS is only supported with [',
  4972.           VALID_METHODS.join(', '), '], not', method);
  4973.       return Promise.resolve(null);
  4974.     }
  4976.     let encryptionScheme = 'cenc';
  4977.     if (method == 'SAMPLE-AES') {
  4978.       encryptionScheme = 'cbcs';
  4979.     }
  4981.     const uri = drmTag.getRequiredAttrValue('URI');
  4982.     const parsedData = shaka.net.DataUriPlugin.parseRaw(uri.split('?')[0]);
  4984.     // The data encoded in the URI is a PlayReady Pro Object, so we need
  4985.     // convert it to pssh.
  4986.     const data = shaka.util.BufferUtils.toUint8(parsedData.data);
  4987.     const systemId = new Uint8Array([
  4988.       0x9a, 0x04, 0xf0, 0x79, 0x98, 0x40, 0x42, 0x86,
  4989.       0xab, 0x92, 0xe6, 0x5b, 0xe0, 0x88, 0x5f, 0x95,
  4990.     ]);
  4991.     const keyIds = new Set();
  4992.     const psshVersion = 0;
  4993.     const pssh =
  4994.         shaka.util.Pssh.createPssh(data, systemId, keyIds, psshVersion);
  4995.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  4996.         'com.microsoft.playready', encryptionScheme, [
  4997.           {initDataType: 'cenc', initData: pssh},
  4998.         ]);
  5000.     const input = shaka.util.TXml.parseXmlString([
  5001.       '<PLAYREADY>',
  5002.       shaka.util.Uint8ArrayUtils.toBase64(data),
  5003.       '</PLAYREADY>',
  5004.     ].join('\n'));
  5005.     if (input) {
  5006.       drmInfo.licenseServerUri = shaka.drm.PlayReady.getLicenseUrl(input);
  5007.     }
  5009.     return Promise.resolve(drmInfo);
  5010.   }
  5012.   /**
  5013.    * @param {!shaka.hls.Tag} drmTag
  5014.    * @param {string} mimeType
  5015.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  5016.    * @return {!Promise<?shaka.extern.DrmInfo>}
  5017.    * @private
  5018.    */
  5019.   wiseplayDrmParser_(drmTag, mimeType, initSegmentRef) {
  5020.     const method = drmTag.getRequiredAttrValue('METHOD');
  5021.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  5022.     if (!VALID_METHODS.includes(method)) {
  5023.       shaka.log.error('WisePlay in HLS is only supported with [',
  5024.           VALID_METHODS.join(', '), '], not', method);
  5025.       return Promise.resolve(null);
  5026.     }
  5028.     let encryptionScheme = 'cenc';
  5029.     if (method == 'SAMPLE-AES') {
  5030.       encryptionScheme = 'cbcs';
  5031.     }
  5033.     const uri = drmTag.getRequiredAttrValue('URI');
  5034.     const parsedData = shaka.net.DataUriPlugin.parseRaw(uri.split('?')[0]);
  5036.     // The data encoded in the URI is a PSSH box to be used as init data.
  5037.     const pssh = shaka.util.BufferUtils.toUint8(parsedData.data);
  5038.     const drmInfo = shaka.util.ManifestParserUtils.createDrmInfo(
  5039.         'com.huawei.wiseplay', encryptionScheme, [
  5040.           {initDataType: 'cenc', initData: pssh},
  5041.         ]);
  5043.     const keyId = drmTag.getAttributeValue('KEYID');
  5044.     if (keyId) {
  5045.       const keyIdLowerCase = keyId.toLowerCase();
  5046.       // This value should begin with '0x':
  5047.       goog.asserts.assert(
  5048.           keyIdLowerCase.startsWith('0x'), 'Incorrect KEYID format!');
  5049.       // But the output should not contain the '0x':
  5050.       drmInfo.keyIds.add(keyIdLowerCase.substr(2));
  5051.     }
  5052.     return Promise.resolve(drmInfo);
  5053.   }
  5055.   /**
  5056.    * See: https://datatracker.ietf.org/doc/html/draft-pantos-hls-rfc8216bis-11#section-5.1
  5057.    *
  5058.    * @param {!shaka.hls.Tag} drmTag
  5059.    * @param {string} mimeType
  5060.    * @param {function(): !Array<string>} getUris
  5061.    * @param {?shaka.media.InitSegmentReference} initSegmentRef
  5062.    * @param {?Map<string, string>=} variables
  5063.    * @return {!Promise<?shaka.extern.DrmInfo>}
  5064.    * @private
  5065.    */
  5066.   async identityDrmParser_(drmTag, mimeType, getUris, initSegmentRef,
  5067.       variables) {
  5068.     if (mimeType == 'video/mp2t') {
  5069.       throw new shaka.util.Error(
  5070.           shaka.util.Error.Severity.CRITICAL,
  5071.           shaka.util.Error.Category.MANIFEST,
  5072.           shaka.util.Error.Code.HLS_MSE_ENCRYPTED_MP2T_NOT_SUPPORTED);
  5073.     }
  5075.     if (shaka.drm.DrmUtils.isMediaKeysPolyfilled('apple')) {
  5076.       throw new shaka.util.Error(
  5077.           shaka.util.Error.Severity.CRITICAL,
  5078.           shaka.util.Error.Category.MANIFEST,
  5079.           shaka.util.Error.Code
  5080.               .HLS_MSE_ENCRYPTED_LEGACY_APPLE_MEDIA_KEYS_NOT_SUPPORTED);
  5081.     }
  5083.     const method = drmTag.getRequiredAttrValue('METHOD');
  5084.     const VALID_METHODS = ['SAMPLE-AES', 'SAMPLE-AES-CTR'];
  5085.     if (!VALID_METHODS.includes(method)) {
  5086.       shaka.log.error('Identity (ClearKey) in HLS is only supported with [',
  5087.           VALID_METHODS.join(', '), '], not', method);
  5088.       return null;
  5089.     }
  5091.     const keyUris = shaka.hls.Utils.constructSegmentUris(
  5092.         getUris(), drmTag.getRequiredAttrValue('URI'), variables);
  5094.     let key;
  5095.     if (keyUris[0].startsWith('data:text/plain;base64,')) {
  5096.       key = shaka.util.Uint8ArrayUtils.toHex(
  5097.           shaka.util.Uint8ArrayUtils.fromBase64(
  5098.               keyUris[0].split('data:text/plain;base64,').pop()));
  5099.     } else {
  5100.       const keyMapKey = keyUris.sort().join('');
  5101.       if (!this.identityKeyMap_.has(keyMapKey)) {
  5102.         const requestType = shaka.net.NetworkingEngine.RequestType.KEY;
  5103.         const request = shaka.net.NetworkingEngine.makeRequest(
  5104.             keyUris, this.config_.retryParameters);
  5105.         const keyResponse = this.makeNetworkRequest_(request, requestType)
  5106.             .promise;
  5107.         this.identityKeyMap_.set(keyMapKey, keyResponse);
  5108.       }
  5109.       const keyResponse = await this.identityKeyMap_.get(keyMapKey);
  5110.       key = shaka.util.Uint8ArrayUtils.toHex(keyResponse.data);
  5111.     }
  5113.     // NOTE: The ClearKey CDM requires a key-id to key mapping.  HLS doesn't
  5114.     // provide a key ID anywhere.  So although we could use the 'URI' attribute
  5115.     // to fetch the actual 16-byte key, without a key ID, we can't provide this
  5116.     // automatically to the ClearKey CDM. By default we assume that keyId is 0,
  5117.     // but we will try to get key ID from Init Segment.
  5118.     // If the application want override this behavior will have to use
  5119.     // player.configure('drm.clearKeys', { ... }) to provide the key IDs
  5120.     // and keys or player.configure('drm.servers.org\.w3\.clearkey', ...) to
  5121.     // provide a ClearKey license server URI.
  5122.     let keyId = '00000000000000000000000000000000';
  5124.     if (initSegmentRef) {
  5125.       const defaultKID = await this.getKeyIdFromInitSegment_(initSegmentRef);
  5126.       if (defaultKID) {
  5127.         keyId = defaultKID;
  5128.       }
  5129.     }
  5131.     const clearkeys = new Map();
  5132.     clearkeys.set(keyId, key);
  5134.     let encryptionScheme = 'cenc';
  5135.     if (method == 'SAMPLE-AES') {
  5136.       encryptionScheme = 'cbcs';
  5137.     }
  5139.     return shaka.util.ManifestParserUtils.createDrmInfoFromClearKeys(
  5140.         clearkeys, encryptionScheme);
  5141.   }
  5143.   /**
  5144.    * @param {!shaka.media.InitSegmentReference} initSegmentRef
  5145.    * @return {!Promise<?string>}
  5146.    * @private
  5147.    */
  5148.   async getKeyIdFromInitSegment_(initSegmentRef) {
  5149.     let keyId = null;
  5150.     if (this.initSegmentToKidMap_.has(initSegmentRef)) {
  5151.       keyId = this.initSegmentToKidMap_.get(initSegmentRef);
  5152.     } else {
  5153.       const initSegmentRequest = shaka.util.Networking.createSegmentRequest(
  5154.           initSegmentRef.getUris(),
  5155.           initSegmentRef.getStartByte(),
  5156.           initSegmentRef.getEndByte(),
  5157.           this.config_.retryParameters);
  5158.       const requestType = shaka.net.NetworkingEngine.RequestType.SEGMENT;
  5159.       const initType =
  5160.           shaka.net.NetworkingEngine.AdvancedRequestType.INIT_SEGMENT;
  5161.       const initResponse = await this.makeNetworkRequest_(
  5162.           initSegmentRequest, requestType, {type: initType}).promise;
  5164.       initSegmentRef.setSegmentData(initResponse.data);
  5166.       keyId = shaka.media.SegmentUtils.getDefaultKID(
  5167.           initResponse.data);
  5168.       this.initSegmentToKidMap_.set(initSegmentRef, keyId);
  5169.     }
  5170.     return keyId;
  5171.   }
  5172. };
  5175. /**
  5176.  * @typedef {{
  5177.  *   stream: !shaka.extern.Stream,
  5178.  *   type: string,
  5179.  *   redirectUris: !Array<string>,
  5180.  *   getUris: function():!Array<string>,
  5181.  *   minTimestamp: number,
  5182.  *   maxTimestamp: number,
  5183.  *   mediaSequenceToStartTime: !Map<number, number>,
  5184.  *   canSkipSegments: boolean,
  5185.  *   canBlockReload: boolean,
  5186.  *   hasEndList: boolean,
  5187.  *   firstSequenceNumber: number,
  5188.  *   nextMediaSequence: number,
  5189.  *   nextPart: number,
  5190.  *   loadedOnce: boolean
  5191.  * }}
  5192.  *
  5193.  * @description
  5194.  * Contains a stream and information about it.
  5195.  *
  5196.  * @property {!shaka.extern.Stream} stream
  5197.  *   The Stream itself.
  5198.  * @property {string} type
  5199.  *   The type value. Could be 'video', 'audio', 'text', or 'image'.
  5200.  * @property {!Array<string>} redirectUris
  5201.  *   The redirect URIs.
  5202.  * @property {function():!Array<string>} getUris
  5203.  *   The verbatim media playlist URIs, as it appeared in the master playlist.
  5204.  * @property {number} minTimestamp
  5205.  *   The minimum timestamp found in the stream.
  5206.  * @property {number} maxTimestamp
  5207.  *   The maximum timestamp found in the stream.
  5208.  * @property {!Map<number, number>} mediaSequenceToStartTime
  5209.  *   A map of media sequence numbers to media start times.
  5210.  *   Only used for VOD content.
  5211.  * @property {boolean} canSkipSegments
  5212.  *   True if the server supports delta playlist updates, and we can send a
  5213.  *   request for a playlist that can skip older media segments.
  5214.  * @property {boolean} canBlockReload
  5215.  *   True if the server supports blocking playlist reload, and we can send a
  5216.  *   request for a playlist that can block reload until some segments are
  5217.  *   present.
  5218.  * @property {boolean} hasEndList
  5219.  *   True if the stream has an EXT-X-ENDLIST tag.
  5220.  * @property {number} firstSequenceNumber
  5221.  *   The sequence number of the first reference. Only calculated if needed.
  5222.  * @property {number} nextMediaSequence
  5223.  *   The next media sequence.
  5224.  * @property {number} nextPart
  5225.  *   The next part.
  5226.  * @property {boolean} loadedOnce
  5227.  *   True if the stream has been loaded at least once.
  5228.  */
  5229. shaka.hls.HlsParser.StreamInfo;
  5232. /**
  5233.  * @typedef {{
  5234.  *   audio: !Array<shaka.hls.HlsParser.StreamInfo>,
  5235.  *   video: !Array<shaka.hls.HlsParser.StreamInfo>
  5236.  * }}
  5237.  *
  5238.  * @description Audio and video stream infos.
  5239.  * @property {!Array<shaka.hls.HlsParser.StreamInfo>} audio
  5240.  * @property {!Array<shaka.hls.HlsParser.StreamInfo>} video
  5241.  */
  5242. shaka.hls.HlsParser.StreamInfos;
  5245. /**
  5246.  * @const {!Map<string, string>}
  5247.  * @private
  5248.  */
  5249. shaka.hls.HlsParser.RAW_FORMATS_TO_MIME_TYPES_ = new Map()
  5250.     .set('aac', 'audio/aac')
  5251.     .set('ac3', 'audio/ac3')
  5252.     .set('ec3', 'audio/ec3')
  5253.     .set('mp3', 'audio/mpeg');
  5256. /**
  5257.  * @const {!Map<string, string>}
  5258.  * @private
  5259.  */
  5260. shaka.hls.HlsParser.AUDIO_EXTENSIONS_TO_MIME_TYPES_ = new Map()
  5261.     .set('mp4', 'audio/mp4')
  5262.     .set('mp4a', 'audio/mp4')
  5263.     .set('m4s', 'audio/mp4')
  5264.     .set('m4i', 'audio/mp4')
  5265.     .set('m4a', 'audio/mp4')
  5266.     .set('m4f', 'audio/mp4')
  5267.     .set('cmfa', 'audio/mp4')
  5268.     // MPEG2-TS also uses video/ for audio: https://bit.ly/TsMse
  5269.     .set('ts', 'video/mp2t')
  5270.     .set('tsa', 'video/mp2t');
  5273. /**
  5274.  * @const {!Map<string, string>}
  5275.  * @private
  5276.  */
  5277. shaka.hls.HlsParser.VIDEO_EXTENSIONS_TO_MIME_TYPES_ = new Map()
  5278.     .set('mp4', 'video/mp4')
  5279.     .set('mp4v', 'video/mp4')
  5280.     .set('m4s', 'video/mp4')
  5281.     .set('m4i', 'video/mp4')
  5282.     .set('m4v', 'video/mp4')
  5283.     .set('m4f', 'video/mp4')
  5284.     .set('cmfv', 'video/mp4')
  5285.     .set('ts', 'video/mp2t')
  5286.     .set('tsv', 'video/mp2t');
  5289. /**
  5290.  * @const {!Map<string, string>}
  5291.  * @private
  5292.  */
  5293. shaka.hls.HlsParser.TEXT_EXTENSIONS_TO_MIME_TYPES_ = new Map()
  5294.     .set('mp4', 'application/mp4')
  5295.     .set('m4s', 'application/mp4')
  5296.     .set('m4i', 'application/mp4')
  5297.     .set('m4f', 'application/mp4')
  5298.     .set('cmft', 'application/mp4')
  5299.     .set('vtt', 'text/vtt')
  5300.     .set('webvtt', 'text/vtt')
  5301.     .set('ttml', 'application/ttml+xml');
  5304. /**
  5305.  * @const {!Map<string, string>}
  5306.  * @private
  5307.  */
  5308. shaka.hls.HlsParser.IMAGE_EXTENSIONS_TO_MIME_TYPES_ = new Map()
  5309.     .set('jpg', 'image/jpeg')
  5310.     .set('png', 'image/png')
  5311.     .set('svg', 'image/svg+xml')
  5312.     .set('webp', 'image/webp')
  5313.     .set('avif', 'image/avif');
  5316. /**
  5317.  * @const {!Map<string, !Map<string, string>>}
  5318.  * @private
  5319.  */
  5320. shaka.hls.HlsParser.EXTENSION_MAP_BY_CONTENT_TYPE_ = new Map()
  5321.     .set('audio', shaka.hls.HlsParser.AUDIO_EXTENSIONS_TO_MIME_TYPES_)
  5322.     .set('video', shaka.hls.HlsParser.VIDEO_EXTENSIONS_TO_MIME_TYPES_)
  5323.     .set('text', shaka.hls.HlsParser.TEXT_EXTENSIONS_TO_MIME_TYPES_)
  5324.     .set('image', shaka.hls.HlsParser.IMAGE_EXTENSIONS_TO_MIME_TYPES_);
  5327. /**
  5328.  * MIME types without init segment.
  5329.  *
  5330.  * @const {!Set<string>}
  5331.  * @private
  5332.  */
  5333. shaka.hls.HlsParser.MIME_TYPES_WITHOUT_INIT_SEGMENT_ = new Set([
  5334.   'video/mp2t',
  5335.   // Containerless types
  5336.   ...shaka.util.MimeUtils.RAW_FORMATS,
  5337. ]);
  5340. /**
  5341.  * @typedef {function(!shaka.hls.Tag,
  5342.  *                    string,
  5343.  *                    ?shaka.media.InitSegmentReference):
  5344.  *                        !Promise<?shaka.extern.DrmInfo>}
  5345.  * @private
  5346.  */
  5347. shaka.hls.HlsParser.DrmParser_;
  5350. /**
  5351.  * @enum {string}
  5352.  * @private
  5353.  */
  5354. shaka.hls.HlsParser.PresentationType_ = {
  5355.   VOD: 'VOD',
  5356.   EVENT: 'EVENT',
  5357.   LIVE: 'LIVE',
  5358. };
  5361. /**
  5362.  * @const {string}
  5363.  * @private
  5364.  */
  5365. shaka.hls.HlsParser.FAKE_MUXED_URL_ = 'shaka://hls-muxed';
  5368. shaka.media.ManifestParser.registerParserByMime(
  5369.     'application/x-mpegurl', () => new shaka.hls.HlsParser());
  5370. shaka.media.ManifestParser.registerParserByMime(
  5371.     'application/vnd.apple.mpegurl', () => new shaka.hls.HlsParser());