// ==UserScript==
// @name         Watch Later Extractor
// @namespace    rbits.watch-later-extractor
// @version      0.0.4
// @description  Exports videos from your YouTube Watch Later page to a JSON file
// @author       rbits
// @match        https://www.youtube.com/playlist*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=youtube.com
// @grant        GM_registerMenuCommand
// @license      GPL3
// ==/UserScript==
function runScript() {
console.log("Watch Later Extractor script running");
let box = document.createElement("div");
box.style = `
color: white;
background-color: #555555;
border-radius: 2rem;
width: 50rem;
height: 20rem;
display: flex;
flex-direction: column;
align-items: center;
justify-content: center;
gap: 2rem;
padding: 2rem;
`;
let textElement = document.createElement("p");
textElement.innerHTML = "Enter id/url of video to stop at<br>(leave blank to process all videos)"
textElement.style = `
font-size: 2rem;
text-align: center;
`
box.appendChild(textElement);
let videoIdInput = document.createElement("input");
videoIdInput.style = `
font-size: 2rem;
width: 80%;
`
box.appendChild(videoIdInput);
let fileType = document.createElement("select");
fileType.innerHTML = `
<option value="json">JSON</option>
<option value="csv">CSV</option>
`;
fileType.style = `
font-size: 2rem;
`
box.appendChild(fileType);
let button = document.createElement("button");
button.textContent = "Start";
button.style = `
font-size: 2rem;
padding: 0.5rem;
`
box.appendChild(button);
let flex = document.createElement("div");
flex.style = `
width: 100vw;
height: 100vh;
position: fixed;
display: flex;
align-items: center;
justify-content: center;
z-index: 9999;
`
flex.appendChild(box);
document.body.appendChild(flex);
button.onclick = () => {
startProcessing(videoIdInput.value, fileType.value);
document.body.removeChild(flex);
};
}
function startProcessing(stopVideoId, fileType) {
// Convert url to id
const videoIdMatch = stopVideoId.match(/\/watch\?v=([^&]*)/);
if (videoIdMatch) {
stopVideoId = videoIdMatch[1];
}
let videosElement = document.querySelector("ytd-playlist-video-renderer").parentElement;
let signals = {
allLoaded: false,
}
parseVideos(videosElement, stopVideoId, signals)
.then((parsedVideos) => handleParsedVideos(parsedVideos, fileType));
repeatScroll(videosElement, signals);
}
// Parses all videos as they appear in videos
// Once signals.allLoaded is set, it finishes parsing all remaining videos then
// returns list of parsed videos
async function parseVideos(videosElement, stopVideoId, signals) {
console.log("Starting video parsing");
if (stopVideoId !== "") {
console.log("Stopping at %s", stopVideoId);
}
let videos = videosElement.children;
let parsedVideos = [];
let i = 0;
let didFinishEarly = false;
// videos can grow at any time
while (true) {
while (i < videos.length - 1) {
const parsedVideo = parseVideo(videos.item(i));
parsedVideos.push(parsedVideo);
i++;
if (parsedVideo.videoId === stopVideoId) {
didFinishEarly = true;
signals.allLoaded = true;
break;
}
}
if (signals.allLoaded) {
break;
}
console.log("Parsed %d videos, waiting for more videos", i);
while (i >= videos.length - 1 && !signals.allLoaded) {
// Wait 0.1s between checks
await new Promise(executor => setTimeout(executor, 100))
}
}
// Usually last item is ytd-continuation-item-renderer so isn't parsed
// It's probably a video now, so it should be parsed now
if (isEnd(videos) && !didFinishEarly) {
const lastItem = videos.item(videos.length - 1);
parsedVideos.push(parseVideo(lastItem));
} else {
console.log("Exited early: parsing finished but continuation item still exists");
}
return parsedVideos;
}
function parseVideo(videoElement) {
// const thumbnail = videoElement.getElementsByTagName("img")[0].src;
const titleElement = videoElement.querySelector("#video-title");
const videoUrl = titleElement.href;
const videoId = videoUrl.match(/\/watch\?v=([^&]*)/)[1];
const title = titleElement.title;
const channelElement = videoElement.querySelector("#channel-name")
.getElementsByTagName("a")[0];
const channelUrl = channelElement.href;
const channelName = channelElement.textContent;
return {
title,
channelName,
videoUrl,
videoId,
channelUrl,
// thumbnail,
};
}
async function repeatScroll(videosElement, signals) {
let videos = videosElement.children;
// No need to scroll, already loaded
if (isEnd(videos)) {
signals.allLoaded = true;
return;
}
const mutationCallback = (_mutationList, observer) => {
if (isEnd(videos) || signals.allLoaded) {
signals.allLoaded = true;
observer.disconnect();
} else {
scrollToBottom()
}
}
const observer = new MutationObserver(mutationCallback);
observer.observe(videosElement, { childList: true });
scrollToBottom();
}
function scrollToBottom() {
window.scroll(0, document.documentElement.scrollHeight);
console.log("Scrolled to " + document.documentElement.scrollHeight);
}
function isEnd(videos) {
const lastItem = videos.item(videos.length - 1);
if (lastItem.tagName === "YTD-PLAYLIST-VIDEO-RENDERER") {
return true;
} else if (lastItem.tagName === "YTD-CONTINUATION-ITEM-RENDERER") {
return false;
} else {
console.error(lastItem.tagName);
throw new Error("Unknown item in video list");
}
}
function handleParsedVideos(parsedVideos, fileType) {
console.log("All videos parsed, creating file");
let fileString = "";
if (fileType === "json") {
fileString = JSON.stringify(parsedVideos);
} else if (fileType === "csv") {
fileString = objListToCsv(parsedVideos);
}
const base64String = stringToBase64(fileString);
var downloadLink = document.createElement("a");
downloadLink.href = "data:text/plain;base64," + base64String;
downloadLink.download = "playlist." + fileType;
downloadLink.click();
// console.dir(parsedVideos);
}
// From https://developer.mozilla.org/en-US/docs/Glossary/Base64
function stringToBase64(string) {
const bytes = new TextEncoder().encode(string);
const binString = Array.from(bytes, (byte) =>
String.fromCodePoint(byte),
).join("");
return btoa(binString);
}
function objListToCsv(objList) {
const columns = Object.keys(objList[0]);
let rows = [];
for (const obj of objList) {
let row = "";
let first = true;
for (const column of columns) {
if (first) {
first = false;
} else {
row += ",";
}
// Surround in quotes and escape quotes
row += "\"" + obj[column].replaceAll("\"", "\"\"") + "\"";
}
rows.push(row);
}
let csv = columns.join(",") + "\n";
csv += rows.join("\n");
return csv;
}
(function() {
'use strict';
GM_registerMenuCommand(
"Run script",
runScript,
);
})();