khinsider batch downloader (mainly written by maple3142)

khinsider-batch-downloader.js

// ==UserScript==
// @name         khinsider Batch Downloader
// @description  batch download for downloads.khinsider.com
// @version      1.0.0
// @match        https://downloads.khinsider.com/game-soundtracks/album/*
// @require      https://cdn.jsdelivr.net/npm/web-streams-polyfill@3.1.1/dist/ponyfill.min.js
// @require      https://cdn.jsdelivr.net/npm/streamsaver@2.0.5/StreamSaver.js
// @require      https://cdn.jsdelivr.net/npm/streamsaver@2.0.5/examples/zip-stream.js
// @connect      23.237.126.42
// @connect      vgmsite.com
// @grant        GM_xmlhttpRequest
// @inspired-by  maple3142 (https://blog.maple3142.net/) - khinsider batch downloader
// ==/UserScript==

function download(url) {
    return new Promise((resolve, reject) => {
        GM_xmlhttpRequest({
            method: 'GET',
            url,
            responseType: 'blob',
            onload: res => resolve(res.response),
        });
    });
}

let started = false;

$('a:contains("click to download")').on('click', async e => {
	e.preventDefault();

    $(e.target).text("Don't close this tab until download complete.");

    if (started) {
        return;
    }

    started = true;

    const title = $('h2')[0].textContent;
    const files = $('tr > td.clickable-row:not([align])')
        .toArray()
        .map(el => $(el).find('a').attr('href'))
        .map(url => {
            const obj = {};
            obj.pageUrl = url;
            obj.blobPromise = fetch(url)
                .then(r => r.text())
                .then(html => {
                    obj.url = $(html).find('a:contains("Click here to download as FLAC")').attr('href')
                            || $(html).find('a:contains("Click here to download as MP3")').attr('href');
                    obj.name = decodeURIComponent(obj.url.split('/').pop());

                    return download(obj.url);
                });

            return obj;
        });

    const ws = streamSaver.createWriteStream(title + '.zip');

    new ZIP({
        async pull(ctrl) {
            const f = files.shift();
            const stream = new Response(await f.blobPromise).body;

            ctrl.enqueue({
                name: f.name,
                stream: () => stream,
            });

            if (files.length === 0) {
                ctrl.close();
            }
        }
    })
    .pipeTo(ws)
    .then(console.log, console.error);
});

An error may occur in StreamSaver.js.

mitm.html:1 Uncaught (in promise) DOMException: Failed to get a ServiceWorkerRegistration: The user denied permission to use Service Worker.

This is related to cookies.
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