Zazama / node-id3

import { FrameBuilder } from "../FrameBuilder"

import { FrameReader } from "../FrameReader"

import { EventTimingCodes } from "../types/TagFrames"

export const ETCO = {

    create: (data: EventTimingCodes): Buffer => {

        return new FrameBuilder("ETCO")

            .appendNumber(data.timeStampFormat, {size: 1})

            .appendArray(data.keyEvents, (builder, keyEvent) => builder

                .appendNumber(keyEvent.type, {size: 1})

                .appendNumber(keyEvent.timeStamp, {size: 4})

            )

            .getBufferWithPartialHeader()

    },

    read: (buffer: Buffer): EventTimingCodes => {

        const reader = new FrameReader(buffer)

        return {

            timeStampFormat: reader.consumeNumber({size: 1}) as

                EventTimingCodes["timeStampFormat"],

            keyEvents: Array.from((function*() {

                while(!reader.isBufferEmpty()) {

                    yield {

                        type: reader.consumeNumber({size: 1}),

                        timeStamp: reader.consumeNumber({size: 4})

                    }

                }

            })())

        }

    }

}