AzuraCast/frontend/vue/components/Public/WebDJ/Track.js

// noinspection all

export default {
    inject: ['getStream', 'resumeStream'],
    data: function () {
        return {
            'controlsNode': null,

            'trackGain': 0,
            'trackGainObj': null,

            'destination': null,
            'sink': null,

            'passThrough': false,
            'passThroughObj': null,

            'source': null,
            'playing': false,
            'paused': false,
            'position': 0.0,
            'volume': 100,
            'volumeLeft': 0,
            'volumeRight': 0
        };
    },
    mounted: function () {
        this.sink = this.getStream().webcast;
    },
    watch: {
        volume: function (val, oldVal) {
            this.setTrackGain(val);
        }
    },
    methods: {
        createControlsNode: function () {
            var bufferLength,
                bufferLog,
                bufferSize,
                log10,
                source;

            bufferSize = 4096;
            bufferLength = parseFloat(bufferSize) / parseFloat(this.getStream().context.sampleRate);
            bufferLog = Math.log(parseFloat(bufferSize));
            log10 = 2.0 * Math.log(10);

            source = this.getStream().context.createScriptProcessor(bufferSize, 2, 2);

            source.onaudioprocess = (buf) => {
                var channel,
                    channelData,
                    i,
                    j,
                    k,
                    ref1,
                    ref2,
                    ref3,
                    results,
                    ret,
                    rms,
                    volume;
                ret = {};

                if (((ref1 = this.source) != null ? ref1.position : void 0) != null) {
                    this.position = this.source.position();
                } else {
                    if (this.source != null) {
                        this.position = parseFloat(this.position) + bufferLength;
                    }
                }
                results = [];
                for (channel = j = 0, ref2 = buf.inputBuffer.numberOfChannels - 1; (0 <= ref2 ? j <= ref2 : j >= ref2); channel = 0 <= ref2 ? ++j : --j) {
                    channelData = buf.inputBuffer.getChannelData(channel);
                    rms = 0.0;
                    for (i = k = 0, ref3 = channelData.length - 1; (0 <= ref3 ? k <= ref3 : k >= ref3); i = 0 <= ref3 ? ++k : --k) {
                        rms += Math.pow(channelData[i], 2);
                    }
                    volume = 100 * Math.exp((Math.log(rms) - bufferLog) / log10);
                    if (channel === 0) {
                        this.volumeLeft = volume;
                    } else {
                        this.volumeRight = volume;
                    }

                    results.push(buf.outputBuffer.getChannelData(channel).set(channelData));
                }
                return results;
            };
            return source;
        },

        createPassThrough: function () {
            var source;
            source = this.getStream().context.createScriptProcessor(256, 2, 2);
            source.onaudioprocess = (buf) => {
                var channel,
                    channelData,
                    j,
                    ref1,
                    results;
                channelData = buf.inputBuffer.getChannelData(channel);
                results = [];
                for (channel = j = 0, ref1 = buf.inputBuffer.numberOfChannels - 1; (0 <= ref1 ? j <= ref1 : j >= ref1); channel = 0 <= ref1 ? ++j : --j) {
                    if (this.passThrough) {
                        results.push(buf.outputBuffer.getChannelData(channel).set(channelData));
                    } else {
                        results.push(buf.outputBuffer.getChannelData(channel).set(new Float32Array(channelData.length)));
                    }
                }
                return results;
            };
            return source;
        },

        setTrackGain: function (new_gain) {
            return (this.trackGainObj) && (this.trackGainObj.gain.value = parseFloat(new_gain) / 100.0);
        },

        togglePause: function () {
            var ref1,
                ref2;
            if (((ref1 = this.source) != null ? ref1.pause : void 0) == null) {
                return;
            }
            if ((ref2 = this.source) != null ? typeof ref2.paused === 'function' ? ref2.paused() : void 0 : void 0) {
                this.source.play();
                this.playing = true;
                this.paused = false;
            } else {
                this.source.pause();
                this.playing = false;
                this.paused = true;
            }
        },

        prepare: function () {
            this.controlsNode = this.createControlsNode();
            this.controlsNode.connect(this.sink);

            this.trackGainObj = this.getStream().context.createGain();
            this.trackGainObj.connect(this.controlsNode);
            this.trackGainObj.gain.value = 1.0;

            this.destination = this.trackGainObj;

            this.passThroughObj = this.createPassThrough();
            this.passThroughObj.connect(this.getStream().context.destination);

            return this.trackGainObj.connect(this.passThroughObj);
        },

        stop: function () {
            var ref1,
                ref2,
                ref3,
                ref4,
                ref5;
            if ((ref1 = this.source) != null) {
                if (typeof ref1.stop === 'function') {
                    ref1.stop();
                }
            }
            if ((ref2 = this.source) != null) {
                ref2.disconnect();
            }
            if ((ref3 = this.trackGainObj) != null) {
                ref3.disconnect();
            }
            if ((ref4 = this.controlsNode) != null) {
                ref4.disconnect();
            }
            if ((ref5 = this.passThroughObj) != null) {
                ref5.disconnect();
            }
            this.source = this.trackGainObj = this.controlsNode = this.passThroughObj = null;

            this.position = 0.0;
            this.volumeLeft = 0;
            this.volumeRight = 0;

            this.playing = false;
            this.paused = false;
        },

        seek: function (percent) {
            var position,
                ref1;
            if (!(position = (ref1 = this.source) != null ? typeof ref1.seek === 'function' ? ref1.seek(percent) : void 0 : void 0)) {
                return;
            }

            this.position = position;
        },

        prettifyTime: function (time) {
            var hours,
                minutes,
                result,
                seconds;
            hours = parseInt(time / 3600);
            time %= 3600;
            minutes = parseInt(time / 60);
            seconds = parseInt(time % 60);
            if (minutes < 10) {
                minutes = `0${minutes}`;
            }
            if (seconds < 10) {
                seconds = `0${seconds}`;
            }
            result = `${minutes}:${seconds}`;
            if (hours > 0) {
                result = `${hours}:${result}`;
            }
            return result;
        },

        sendMetadata: function (file) {
            this.getStream().webcast.sendMetadata(file.metadata);
        }
    }
};