Zazama / node-id3

import { TextEncoding } from "../definitions/Encoding"

import { FrameBuilder } from "../FrameBuilder"

import { FrameReader } from "../FrameReader"

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

import { isString } from '../util'

import { validateLanguageCode } from "./util"

export const USLT = {

    create: (data: UnsynchronisedLyrics | string): Buffer => {

        if(isString(data)) {

            // TODO: we should probably not accept a string only,

            // as the language is not optionalm default to eng for now.

            data = {

                language: 'eng',

                text: data

            }

        }

        if (data.text == undefined) {

            throw new TypeError("A description text must be provided")

        }

        return new FrameBuilder("USLT", TextEncoding.UTF_16_WITH_BOM)

            .appendText(validateLanguageCode(data.language))

            .appendTerminatedTextWithFrameEncoding(data.shortText ?? "")

            .appendTextWithFrameEncoding(data.text)

            .getBufferWithPartialHeader()

    },

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

        const reader = new FrameReader(buffer, {consumeEncodingByte: true})

        return {

            language: reader.consumeText({ size: 3}),

            shortText: reader.consumeTerminatedTextWithFrameEncoding(),

            text: reader.consumeTextWithFrameEncoding()

        }

    }

}