dashjs/src/dash/controllers/SegmentsController.js

A reference client implementation for the playback of MPEG DASH via Javascript and compliant browsers.

/**
 * The copyright in this software is being made available under the BSD License,
 * included below. This software may be subject to other third party and contributor
 * rights, including patent rights, and no such rights are granted under this license.
 *
 * Copyright (c) 2013, Dash Industry Forum.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *  * Redistributions of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright notice,
 *  this list of conditions and the following disclaimer in the documentation and/or
 *  other materials provided with the distribution.
 *  * Neither the name of Dash Industry Forum nor the names of its
 *  contributors may be used to endorse or promote products derived from this software
 *  without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS AS IS AND ANY
 *  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 *  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 *  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 */
import DashConstants from '../constants/DashConstants';
import FactoryMaker from '../../core/FactoryMaker';
import TimelineSegmentsGetter from '../utils/TimelineSegmentsGetter';
import TemplateSegmentsGetter from '../utils/TemplateSegmentsGetter';
import ListSegmentsGetter from '../utils/ListSegmentsGetter';
import SegmentBaseGetter from '../utils/SegmentBaseGetter';

import SegmentBaseLoader from '../SegmentBaseLoader';
import WebmSegmentBaseLoader from '../WebmSegmentBaseLoader';


function SegmentsController(config) {
    config = config || {};

    const context = this.context;

    const dashMetrics = config.dashMetrics;
    const mediaPlayerModel = config.mediaPlayerModel;
    const errHandler = config.errHandler;
    const baseURLController = config.baseURLController;

    let instance,
        getters,
        segmentBaseLoader;

    function setup() {
        getters = {};

        segmentBaseLoader = isWebM(config.mimeType) ? WebmSegmentBaseLoader(context).getInstance() : SegmentBaseLoader(context).getInstance();
        segmentBaseLoader.setConfig({
            baseURLController: baseURLController,
            dashMetrics: dashMetrics,
            mediaPlayerModel: mediaPlayerModel,
            errHandler: errHandler
        });
    }

    function isWebM(mimeType) {
        const type = mimeType ? mimeType.split('/')[1] : '';
        return 'webm' === type.toLowerCase();
    }

    function initialize(isDynamic) {
        segmentBaseLoader.initialize();

        getters[DashConstants.SEGMENT_TIMELINE] = TimelineSegmentsGetter(context).create(config, isDynamic);
        getters[DashConstants.SEGMENT_TEMPLATE] = TemplateSegmentsGetter(context).create(config, isDynamic);
        getters[DashConstants.SEGMENT_LIST] = ListSegmentsGetter(context).create(config, isDynamic);
        getters[DashConstants.SEGMENT_BASE] = SegmentBaseGetter(context).create(config, isDynamic);
    }

    function update(voRepresentation, type, hasInitialization, hasSegments) {
        if (!hasInitialization) {
            updateInitSegment(voRepresentation);
        }

        if (!hasSegments) {
            updateSegments(voRepresentation, type);
        }
    }

    function updateInitSegment(voRepresentation) {
        segmentBaseLoader.loadInitialization(voRepresentation);
    }

    function updateSegments(voRepresentation, type) {
        segmentBaseLoader.loadSegments(voRepresentation, type, voRepresentation.indexRange);
    }

    function getSegmentsGetter(representation) {
        if (representation.segments) {
            return getters[DashConstants.SEGMENT_BASE];
        }
        return getters[representation.segmentInfoType];
    }

    function getSegmentByIndex(representation, index, lastSegmentTime) {
        const getter = getSegmentsGetter(representation);
        if (getter) {
            return getter.getSegmentByIndex(representation, index, lastSegmentTime);
        }
        return null;
    }

    function getSegmentByTime(representation, time) {
        const getter = getSegmentsGetter(representation);
        if (getter) {
            return getter.getSegmentByTime(representation, time);
        }
        return null;
    }

    instance = {
        initialize: initialize,
        update: update,
        getSegmentByIndex: getSegmentByIndex,
        getSegmentByTime: getSegmentByTime
    };

    setup();

    return instance;
}

SegmentsController.__dashjs_factory_name = 'SegmentsController';
const factory = FactoryMaker.getClassFactory(SegmentsController);
export default factory;