/**
 * @copyright 2024 Double Bastion LLC <www.doublebastion.com>
 *
 * @author Double Bastion LLC
 *
 * @license GNU AGPL version 3 or any later version
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 *  The code in this file is identical with that of the
 *  original file "fix-webm-duration.js" released under the MIT License:
 *  https://github.com/yusitnikov/fix-webm-duration/blob/master/LICENSE.
 *  The copyright notice for the original file follows:
 */
/**
 * The MIT license
 *
 * Copyright (c) 2018 Yury Sitnikov
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */


(function (name, definition) {
    if (typeof define === 'function' && define.amd) { // RequireJS / AMD
        define(definition);
    } else if (typeof module !== 'undefined' && module.exports) { // CommonJS / Node.js
        module.exports = definition();
    } else { // Direct include
        window.ysFixWebmDuration = definition();
    }
})('fix-webm-duration', function () {
    /*
     * This is the list of possible WEBM file sections by their IDs.
     * Possible types: Container, Binary, Uint, Int, String, Float, Date
     */
    var sections = {
        0xa45dfa3: { name: 'EBML', type: 'Container' },
        0x286: { name: 'EBMLVersion', type: 'Uint' },
        0x2f7: { name: 'EBMLReadVersion', type: 'Uint' },
        0x2f2: { name: 'EBMLMaxIDLength', type: 'Uint' },
        0x2f3: { name: 'EBMLMaxSizeLength', type: 'Uint' },
        0x282: { name: 'DocType', type: 'String' },
        0x287: { name: 'DocTypeVersion', type: 'Uint' },
        0x285: { name: 'DocTypeReadVersion', type: 'Uint' },
        0x6c: { name: 'Void', type: 'Binary' },
        0x3f: { name: 'CRC-32', type: 'Binary' },
        0xb538667: { name: 'SignatureSlot', type: 'Container' },
        0x3e8a: { name: 'SignatureAlgo', type: 'Uint' },
        0x3e9a: { name: 'SignatureHash', type: 'Uint' },
        0x3ea5: { name: 'SignaturePublicKey', type: 'Binary' },
        0x3eb5: { name: 'Signature', type: 'Binary' },
        0x3e5b: { name: 'SignatureElements', type: 'Container' },
        0x3e7b: { name: 'SignatureElementList', type: 'Container' },
        0x2532: { name: 'SignedElement', type: 'Binary' },
        0x8538067: { name: 'Segment', type: 'Container' },
        0x14d9b74: { name: 'SeekHead', type: 'Container' },
        0xdbb: { name: 'Seek', type: 'Container' },
        0x13ab: { name: 'SeekID', type: 'Binary' },
        0x13ac: { name: 'SeekPosition', type: 'Uint' },
        0x549a966: { name: 'Info', type: 'Container' },
        0x33a4: { name: 'SegmentUID', type: 'Binary' },
        0x3384: { name: 'SegmentFilename', type: 'String' },
        0x1cb923: { name: 'PrevUID', type: 'Binary' },
        0x1c83ab: { name: 'PrevFilename', type: 'String' },
        0x1eb923: { name: 'NextUID', type: 'Binary' },
        0x1e83bb: { name: 'NextFilename', type: 'String' },
        0x444: { name: 'SegmentFamily', type: 'Binary' },
        0x2924: { name: 'ChapterTranslate', type: 'Container' },
        0x29fc: { name: 'ChapterTranslateEditionUID', type: 'Uint' },
        0x29bf: { name: 'ChapterTranslateCodec', type: 'Uint' },
        0x29a5: { name: 'ChapterTranslateID', type: 'Binary' },
        0xad7b1: { name: 'TimecodeScale', type: 'Uint' },
        0x489: { name: 'Duration', type: 'Float' },
        0x461: { name: 'DateUTC', type: 'Date' },
        0x3ba9: { name: 'Title', type: 'String' },
        0xd80: { name: 'MuxingApp', type: 'String' },
        0x1741: { name: 'WritingApp', type: 'String' },
        // 0xf43b675: { name: 'Cluster', type: 'Container' },
        0x67: { name: 'Timecode', type: 'Uint' },
        0x1854: { name: 'SilentTracks', type: 'Container' },
        0x18d7: { name: 'SilentTrackNumber', type: 'Uint' },
        0x27: { name: 'Position', type: 'Uint' },
        0x2b: { name: 'PrevSize', type: 'Uint' },
        0x23: { name: 'SimpleBlock', type: 'Binary' },
        0x20: { name: 'BlockGroup', type: 'Container' },
        0x21: { name: 'Block', type: 'Binary' },
        0x22: { name: 'BlockVirtual', type: 'Binary' },
        0x35a1: { name: 'BlockAdditions', type: 'Container' },
        0x26: { name: 'BlockMore', type: 'Container' },
        0x6e: { name: 'BlockAddID', type: 'Uint' },
        0x25: { name: 'BlockAdditional', type: 'Binary' },
        0x1b: { name: 'BlockDuration', type: 'Uint' },
        0x7a: { name: 'ReferencePriority', type: 'Uint' },
        0x7b: { name: 'ReferenceBlock', type: 'Int' },
        0x7d: { name: 'ReferenceVirtual', type: 'Int' },
        0x24: { name: 'CodecState', type: 'Binary' },
        0x35a2: { name: 'DiscardPadding', type: 'Int' },
        0xe: { name: 'Slices', type: 'Container' },
        0x68: { name: 'TimeSlice', type: 'Container' },
        0x4c: { name: 'LaceNumber', type: 'Uint' },
        0x4d: { name: 'FrameNumber', type: 'Uint' },
        0x4b: { name: 'BlockAdditionID', type: 'Uint' },
        0x4e: { name: 'Delay', type: 'Uint' },
        0x4f: { name: 'SliceDuration', type: 'Uint' },
        0x48: { name: 'ReferenceFrame', type: 'Container' },
        0x49: { name: 'ReferenceOffset', type: 'Uint' },
        0x4a: { name: 'ReferenceTimeCode', type: 'Uint' },
        0x2f: { name: 'EncryptedBlock', type: 'Binary' },
        0x654ae6b: { name: 'Tracks', type: 'Container' },
        0x2e: { name: 'TrackEntry', type: 'Container' },
        0x57: { name: 'TrackNumber', type: 'Uint' },
        0x33c5: { name: 'TrackUID', type: 'Uint' },
        0x3: { name: 'TrackType', type: 'Uint' },
        0x39: { name: 'FlagEnabled', type: 'Uint' },
        0x8: { name: 'FlagDefault', type: 'Uint' },
        0x15aa: { name: 'FlagForced', type: 'Uint' },
        0x1c: { name: 'FlagLacing', type: 'Uint' },
        0x2de7: { name: 'MinCache', type: 'Uint' },
        0x2df8: { name: 'MaxCache', type: 'Uint' },
        0x3e383: { name: 'DefaultDuration', type: 'Uint' },
        0x34e7a: { name: 'DefaultDecodedFieldDuration', type: 'Uint' },
        0x3314f: { name: 'TrackTimecodeScale', type: 'Float' },
        0x137f: { name: 'TrackOffset', type: 'Int' },
        0x15ee: { name: 'MaxBlockAdditionID', type: 'Uint' },
        0x136e: { name: 'Name', type: 'String' },
        0x2b59c: { name: 'Language', type: 'String' },
        0x6: { name: 'CodecID', type: 'String' },
        0x23a2: { name: 'CodecPrivate', type: 'Binary' },
        0x58688: { name: 'CodecName', type: 'String' },
        0x3446: { name: 'AttachmentLink', type: 'Uint' },
        0x1a9697: { name: 'CodecSettings', type: 'String' },
        0x1b4040: { name: 'CodecInfoURL', type: 'String' },
        0x6b240: { name: 'CodecDownloadURL', type: 'String' },
        0x2a: { name: 'CodecDecodeAll', type: 'Uint' },
        0x2fab: { name: 'TrackOverlay', type: 'Uint' },
        0x16aa: { name: 'CodecDelay', type: 'Uint' },
        0x16bb: { name: 'SeekPreRoll', type: 'Uint' },
        0x2624: { name: 'TrackTranslate', type: 'Container' },
        0x26fc: { name: 'TrackTranslateEditionUID', type: 'Uint' },
        0x26bf: { name: 'TrackTranslateCodec', type: 'Uint' },
        0x26a5: { name: 'TrackTranslateTrackID', type: 'Binary' },
        0x60: { name: 'Video', type: 'Container' },
        0x1a: { name: 'FlagInterlaced', type: 'Uint' },
        0x13b8: { name: 'StereoMode', type: 'Uint' },
        0x13c0: { name: 'AlphaMode', type: 'Uint' },
        0x13b9: { name: 'OldStereoMode', type: 'Uint' },
        0x30: { name: 'PixelWidth', type: 'Uint' },
        0x3a: { name: 'PixelHeight', type: 'Uint' },
        0x14aa: { name: 'PixelCropBottom', type: 'Uint' },
        0x14bb: { name: 'PixelCropTop', type: 'Uint' },
        0x14cc: { name: 'PixelCropLeft', type: 'Uint' },
        0x14dd: { name: 'PixelCropRight', type: 'Uint' },
        0x14b0: { name: 'DisplayWidth', type: 'Uint' },
        0x14ba: { name: 'DisplayHeight', type: 'Uint' },
        0x14b2: { name: 'DisplayUnit', type: 'Uint' },
        0x14b3: { name: 'AspectRatioType', type: 'Uint' },
        0xeb524: { name: 'ColourSpace', type: 'Binary' },
        0xfb523: { name: 'GammaValue', type: 'Float' },
        0x383e3: { name: 'FrameRate', type: 'Float' },
        0x61: { name: 'Audio', type: 'Container' },
        0x35: { name: 'SamplingFrequency', type: 'Float' },
        0x38b5: { name: 'OutputSamplingFrequency', type: 'Float' },
        0x1f: { name: 'Channels', type: 'Uint' },
        0x3d7b: { name: 'ChannelPositions', type: 'Binary' },
        0x2264: { name: 'BitDepth', type: 'Uint' },
        0x62: { name: 'TrackOperation', type: 'Container' },
        0x63: { name: 'TrackCombinePlanes', type: 'Container' },
        0x64: { name: 'TrackPlane', type: 'Container' },
        0x65: { name: 'TrackPlaneUID', type: 'Uint' },
        0x66: { name: 'TrackPlaneType', type: 'Uint' },
        0x69: { name: 'TrackJoinBlocks', type: 'Container' },
        0x6d: { name: 'TrackJoinUID', type: 'Uint' },
        0x40: { name: 'TrickTrackUID', type: 'Uint' },
        0x41: { name: 'TrickTrackSegmentUID', type: 'Binary' },
        0x46: { name: 'TrickTrackFlag', type: 'Uint' },
        0x47: { name: 'TrickMasterTrackUID', type: 'Uint' },
        0x44: { name: 'TrickMasterTrackSegmentUID', type: 'Binary' },
        0x2d80: { name: 'ContentEncodings', type: 'Container' },
        0x2240: { name: 'ContentEncoding', type: 'Container' },
        0x1031: { name: 'ContentEncodingOrder', type: 'Uint' },
        0x1032: { name: 'ContentEncodingScope', type: 'Uint' },
        0x1033: { name: 'ContentEncodingType', type: 'Uint' },
        0x1034: { name: 'ContentCompression', type: 'Container' },
        0x254: { name: 'ContentCompAlgo', type: 'Uint' },
        0x255: { name: 'ContentCompSettings', type: 'Binary' },
        0x1035: { name: 'ContentEncryption', type: 'Container' },
        0x7e1: { name: 'ContentEncAlgo', type: 'Uint' },
        0x7e2: { name: 'ContentEncKeyID', type: 'Binary' },
        0x7e3: { name: 'ContentSignature', type: 'Binary' },
        0x7e4: { name: 'ContentSigKeyID', type: 'Binary' },
        0x7e5: { name: 'ContentSigAlgo', type: 'Uint' },
        0x7e6: { name: 'ContentSigHashAlgo', type: 'Uint' },
        0xc53bb6b: { name: 'Cues', type: 'Container' },
        0x3b: { name: 'CuePoint', type: 'Container' },
        0x33: { name: 'CueTime', type: 'Uint' },
        0x37: { name: 'CueTrackPositions', type: 'Container' },
        0x77: { name: 'CueTrack', type: 'Uint' },
        0x71: { name: 'CueClusterPosition', type: 'Uint' },
        0x70: { name: 'CueRelativePosition', type: 'Uint' },
        0x32: { name: 'CueDuration', type: 'Uint' },
        0x1378: { name: 'CueBlockNumber', type: 'Uint' },
        0x6a: { name: 'CueCodecState', type: 'Uint' },
        0x5b: { name: 'CueReference', type: 'Container' },
        0x16: { name: 'CueRefTime', type: 'Uint' },
        0x17: { name: 'CueRefCluster', type: 'Uint' },
        0x135f: { name: 'CueRefNumber', type: 'Uint' },
        0x6b: { name: 'CueRefCodecState', type: 'Uint' },
        0x941a469: { name: 'Attachments', type: 'Container' },
        0x21a7: { name: 'AttachedFile', type: 'Container' },
        0x67e: { name: 'FileDescription', type: 'String' },
        0x66e: { name: 'FileName', type: 'String' },
        0x660: { name: 'FileMimeType', type: 'String' },
        0x65c: { name: 'FileData', type: 'Binary' },
        0x6ae: { name: 'FileUID', type: 'Uint' },
        0x675: { name: 'FileReferral', type: 'Binary' },
        0x661: { name: 'FileUsedStartTime', type: 'Uint' },
        0x662: { name: 'FileUsedEndTime', type: 'Uint' },
        0x43a770: { name: 'Chapters', type: 'Container' },
        0x5b9: { name: 'EditionEntry', type: 'Container' },
        0x5bc: { name: 'EditionUID', type: 'Uint' },
        0x5bd: { name: 'EditionFlagHidden', type: 'Uint' },
        0x5db: { name: 'EditionFlagDefault', type: 'Uint' },
        0x5dd: { name: 'EditionFlagOrdered', type: 'Uint' },
        0x36: { name: 'ChapterAtom', type: 'Container' },
        0x33c4: { name: 'ChapterUID', type: 'Uint' },
        0x1654: { name: 'ChapterStringUID', type: 'String' },
        0x11: { name: 'ChapterTimeStart', type: 'Uint' },
        0x12: { name: 'ChapterTimeEnd', type: 'Uint' },
        0x18: { name: 'ChapterFlagHidden', type: 'Uint' },
        0x598: { name: 'ChapterFlagEnabled', type: 'Uint' },
        0x2e67: { name: 'ChapterSegmentUID', type: 'Binary' },
        0x2ebc: { name: 'ChapterSegmentEditionUID', type: 'Uint' },
        0x23c3: { name: 'ChapterPhysicalEquiv', type: 'Uint' },
        0xf: { name: 'ChapterTrack', type: 'Container' },
        0x9: { name: 'ChapterTrackNumber', type: 'Uint' },
        0x0: { name: 'ChapterDisplay', type: 'Container' },
        0x5: { name: 'ChapString', type: 'String' },
        0x37c: { name: 'ChapLanguage', type: 'String' },
        0x37e: { name: 'ChapCountry', type: 'String' },
        0x2944: { name: 'ChapProcess', type: 'Container' },
        0x2955: { name: 'ChapProcessCodecID', type: 'Uint' },
        0x50d: { name: 'ChapProcessPrivate', type: 'Binary' },
        0x2911: { name: 'ChapProcessCommand', type: 'Container' },
        0x2922: { name: 'ChapProcessTime', type: 'Uint' },
        0x2933: { name: 'ChapProcessData', type: 'Binary' },
        0x254c367: { name: 'Tags', type: 'Container' },
        0x3373: { name: 'Tag', type: 'Container' },
        0x23c0: { name: 'Targets', type: 'Container' },
        0x28ca: { name: 'TargetTypeValue', type: 'Uint' },
        0x23ca: { name: 'TargetType', type: 'String' },
        0x23c5: { name: 'TagTrackUID', type: 'Uint' },
        0x23c9: { name: 'TagEditionUID', type: 'Uint' },
        0x23c4: { name: 'TagChapterUID', type: 'Uint' },
        0x23c6: { name: 'TagAttachmentUID', type: 'Uint' },
        0x27c8: { name: 'SimpleTag', type: 'Container' },
        0x5a3: { name: 'TagName', type: 'String' },
        0x47a: { name: 'TagLanguage', type: 'String' },
        0x484: { name: 'TagDefault', type: 'Uint' },
        0x487: { name: 'TagString', type: 'String' },
        0x485: { name: 'TagBinary', type: 'Binary' }
    };

    function doInherit(newClass, baseClass) {
        newClass.prototype = Object.create(baseClass.prototype);
        newClass.prototype.constructor = newClass;
    }

    function WebmBase(name, type) {
        this.name = name || 'Unknown';
        this.type = type || 'Unknown';
    }
    WebmBase.prototype.updateBySource = function() { };
    WebmBase.prototype.setSource = function(source) {
        this.source = source;
        this.updateBySource();
    };
    WebmBase.prototype.updateByData = function() { };
    WebmBase.prototype.setData = function(data) {
        this.data = data;
        this.updateByData();
    };

    function WebmUint(name, type) {
        WebmBase.call(this, name, type || 'Uint');
    }
    doInherit(WebmUint, WebmBase);
    function padHex(hex) {
        return hex.length % 2 === 1 ? '0' + hex : hex;
    }
    WebmUint.prototype.updateBySource = function() {
        // use hex representation of a number instead of number value
        this.data = '';
        for (var i = 0; i < this.source.length; i++) {
            var hex = this.source[i].toString(16);
            this.data += padHex(hex);
        }
    };
    WebmUint.prototype.updateByData = function() {
        var length = this.data.length / 2;
        this.source = new Uint8Array(length);
        for (var i = 0; i < length; i++) {
            var hex = this.data.substr(i * 2, 2);
            this.source[i] = parseInt(hex, 16);
        }
    };
    WebmUint.prototype.getValue = function() {
        return parseInt(this.data, 16);
    };
    WebmUint.prototype.setValue = function(value) {
        this.setData(padHex(value.toString(16)));
    };

    function WebmFloat(name, type) {
        WebmBase.call(this, name, type || 'Float');
    }
    doInherit(WebmFloat, WebmBase);
    WebmFloat.prototype.getFloatArrayType = function() {
        return this.source && this.source.length === 4 ? Float32Array : Float64Array;
    };
    WebmFloat.prototype.updateBySource = function() {
        var byteArray = this.source.reverse();
        var floatArrayType = this.getFloatArrayType();
        var floatArray = new floatArrayType(byteArray.buffer);
        this.data = floatArray[0];
    };
    WebmFloat.prototype.updateByData = function() {
        var floatArrayType = this.getFloatArrayType();
        var floatArray = new floatArrayType([ this.data ]);
        var byteArray = new Uint8Array(floatArray.buffer);
        this.source = byteArray.reverse();
    };
    WebmFloat.prototype.getValue = function() {
        return this.data;
    };
    WebmFloat.prototype.setValue = function(value) {
        this.setData(value);
    };

    function WebmContainer(name, type) {
        WebmBase.call(this, name, type || 'Container');
    }
    doInherit(WebmContainer, WebmBase);
    WebmContainer.prototype.readByte = function() {
        return this.source[this.offset++];
    };
    WebmContainer.prototype.readUint = function() {
        var firstByte = this.readByte();
        var bytes = 8 - firstByte.toString(2).length;
        var value = firstByte - (1 << (7 - bytes));
        for (var i = 0; i < bytes; i++) {
            // don't use bit operators to support x86
            value *= 256;
            value += this.readByte();
        }
        return value;
    };
    WebmContainer.prototype.updateBySource = function() {
        this.data = [];
        for (this.offset = 0; this.offset < this.source.length; this.offset = end) {
            var id = this.readUint();
            var len = this.readUint();
            var end = Math.min(this.offset + len, this.source.length);
            var data = this.source.slice(this.offset, end);

            var info = sections[id] || { name: 'Unknown', type: 'Unknown' };
            var ctr = WebmBase;
            switch (info.type) {
                case 'Container':
                    ctr = WebmContainer;
                    break;
                case 'Uint':
                    ctr = WebmUint;
                    break;
                case 'Float':
                    ctr = WebmFloat;
                    break;
            }
            var section = new ctr(info.name, info.type);
            section.setSource(data);
            this.data.push({
                id: id,
                idHex: id.toString(16),
                data: section
            });
        }
    };
    WebmContainer.prototype.writeUint = function(x, draft) {
        for (var bytes = 1, flag = 0x80; x >= flag && bytes < 8; bytes++, flag *= 0x80) { }

        if (!draft) {
            var value = flag + x;
            for (var i = bytes - 1; i >= 0; i--) {
                // don't use bit operators to support x86
                var c = value % 256;
                this.source[this.offset + i] = c;
                value = (value - c) / 256;
            }
        }

        this.offset += bytes;
    };
    WebmContainer.prototype.writeSections = function(draft) {
        this.offset = 0;
        for (var i = 0; i < this.data.length; i++) {
            var section = this.data[i],
                content = section.data.source,
                contentLength = content.length;
            this.writeUint(section.id, draft);
            this.writeUint(contentLength, draft);
            if (!draft) {
                this.source.set(content, this.offset);
            }
            this.offset += contentLength;
        }
        return this.offset;
    };
    WebmContainer.prototype.updateByData = function() {
        // run without accessing this.source to determine total length - need to know it to create Uint8Array
        var length = this.writeSections('draft');
        this.source = new Uint8Array(length);
        // now really write data
        this.writeSections();
    };
    WebmContainer.prototype.getSectionById = function(id) {
        for (var i = 0; i < this.data.length; i++) {
            var section = this.data[i];
            if (section.id === id) {
                return section.data;
            }
        }
        return null;
    };

    function WebmFile(source) {
        WebmContainer.call(this, 'File', 'File');
        this.setSource(source);
    }
    doInherit(WebmFile, WebmContainer);
    WebmFile.prototype.fixDuration = function(duration, options) {
        var logger = options && options.logger;
        if (logger === undefined) {
            logger = function(message) {
                console.log(message);
            };
        } else if (!logger) {
            logger = function() { };
        }

        var segmentSection = this.getSectionById(0x8538067);
        if (!segmentSection) {
            logger('[fix-webm-duration] Segment section is missing');
            return false;
        }

        var infoSection = segmentSection.getSectionById(0x549a966);
        if (!infoSection) {
            logger('[fix-webm-duration] Info section is missing');
            return false;
        }

        var timeScaleSection = infoSection.getSectionById(0xad7b1);
        if (!timeScaleSection) {
            logger('[fix-webm-duration] TimecodeScale section is missing');
            return false;
        }

        var durationSection = infoSection.getSectionById(0x489);
        if (durationSection) {
            if (durationSection.getValue() <= 0) {
                logger('[fix-webm-duration] Duration section is present, but the value is empty');
                durationSection.setValue(duration);
            } else {
                logger('[fix-webm-duration] Duration section is present');
                return false;
            }
        } else {
            logger('[fix-webm-duration] Duration section is missing');
            // append Duration section
            durationSection = new WebmFloat('Duration', 'Float');
            durationSection.setValue(duration);
            infoSection.data.push({
                id: 0x489,
                data: durationSection
            });
        }

        // set default time scale to 1 millisecond (1000000 nanoseconds)
        timeScaleSection.setValue(1000000);
        infoSection.updateByData();
        segmentSection.updateByData();
        this.updateByData();

        return true;
    };
    WebmFile.prototype.toBlob = function(mimeType) {
        return new Blob([ this.source.buffer ], { type: mimeType || 'video/webm' });
    };

    function fixWebmDuration(blob, duration, callback, options) {
        // The callback may be omitted - then the third argument is options
        if (typeof callback === "object") {
            options = callback;
            callback = undefined;
        }

        if (!callback) {
            return new Promise(function(resolve) {
                fixWebmDuration(blob, duration, resolve, options);
            });
        }

        try {
            var reader = new FileReader();
            reader.onloadend = function() {
                try {
                    var file = new WebmFile(new Uint8Array(reader.result));
                    if (file.fixDuration(duration, options)) {
                        blob = file.toBlob(blob.type);
                    }
                } catch (ex) {
                    // ignore
                }
                callback(blob);
            };
            reader.readAsArrayBuffer(blob);
        } catch (ex) {
            callback(blob);
        }
    }

    // Support AMD import default
    fixWebmDuration.default = fixWebmDuration;

    return fixWebmDuration;
});
