/*
content script running on youtube.com
*/
'use strict';
const downloadIcon = ``;
const checkmarkIcon = ``;
const defaultIcon = ``;
let browserType = getBrowser();
// boilerplate to dedect browser type api
function getBrowser() {
if (typeof chrome !== 'undefined') {
if (typeof browser !== 'undefined') {
console.log('detected firefox');
return browser;
} else {
console.log('detected chrome');
return chrome;
}
} else {
console.log('failed to dedect browser');
throw 'browser detection error';
}
}
function getChannelContainers() {
const elements = document.querySelectorAll('.yt-flexible-actions-view-model-wiz, #owner');
const channelContainerNodes = [];
elements.forEach(element => {
if (isElementVisible(element)) {
channelContainerNodes.push(element);
}
});
return channelContainerNodes;
}
function isElementVisible(element) {
return element.offsetWidth > 0 || element.offsetHeight > 0 || element.getClientRects().length > 0;
}
function ensureTALinks() {
let channelContainerNodes = getChannelContainers();
for (let channelContainer of channelContainerNodes) {
channelContainer = adjustOwner(channelContainer);
if (channelContainer.hasTA) continue;
let channelButton = buildChannelButton(channelContainer);
channelContainer.appendChild(channelButton);
channelContainer.hasTA = true;
}
let titleContainerNodes = getTitleContainers();
for (let titleContainer of titleContainerNodes) {
let parent = getNearestH3(titleContainer);
if (!parent) continue;
if (parent.hasTA) continue;
let videoButton = buildVideoButton(titleContainer);
if (videoButton == null) continue;
processTitle(parent);
parent.appendChild(videoButton);
parent.hasTA = true;
}
}
ensureTALinks = throttled(ensureTALinks, 700);
function adjustOwner(channelContainer) {
return channelContainer.querySelector('#buttons') || channelContainer;
}
function buildChannelButton(channelContainer) {
let channelHandle = getChannelHandle(channelContainer);
channelContainer.taDerivedHandle = channelHandle;
let buttonDiv = buildChannelButtonDiv();
let channelSubButton = buildChannelSubButton(channelHandle);
buttonDiv.appendChild(channelSubButton);
channelContainer.taSubButton = channelSubButton;
let spacer = buildSpacer();
buttonDiv.appendChild(spacer);
let channelDownloadButton = buildChannelDownloadButton();
buttonDiv.appendChild(channelDownloadButton);
channelContainer.taDownloadButton = channelDownloadButton;
if (!channelContainer.taObserver) {
function updateButtonsIfNecessary() {
let newHandle = getChannelHandle(channelContainer);
if (channelContainer.taDerivedHandle === newHandle) return;
console.log(`updating handle from ${channelContainer.taDerivedHandle} to ${newHandle}`);
channelContainer.taDerivedHandle = newHandle;
let channelSubButton = buildChannelSubButton(newHandle);
channelContainer.taSubButton.replaceWith(channelSubButton);
channelContainer.taSubButton = channelSubButton;
let channelDownloadButton = buildChannelDownloadButton();
channelContainer.taDownloadButton.replaceWith(channelDownloadButton);
channelContainer.taDownloadButton = channelDownloadButton;
}
channelContainer.taObserver = new MutationObserver(throttled(updateButtonsIfNecessary, 100));
channelContainer.taObserver.observe(channelContainer, {
attributes: true,
childList: true,
subtree: true,
});
}
return buttonDiv;
}
function getChannelHandle(channelContainer) {
let channelHandle;
const videoOwnerRenderer = channelContainer.querySelector('.ytd-video-owner-renderer');
if (!videoOwnerRenderer) {
const channelHandleContainer = document.querySelector(
'.yt-content-metadata-view-model-wiz__metadata-text'
);
channelHandle = channelHandleContainer ? channelHandleContainer.innerText : null;
} else {
const href = videoOwnerRenderer.href;
if (href) {
const urlObj = new URL(href);
channelHandle = urlObj.pathname.split('/')[1];
}
}
return channelHandle;
}
function buildChannelButtonDiv() {
let buttonDiv = document.createElement('div');
buttonDiv.classList.add('ta-channel-button');
Object.assign(buttonDiv.style, {
display: 'flex',
alignItems: 'center',
backgroundColor: '#00202f',
color: '#fff',
fontSize: '14px',
padding: '5px',
'margin-left': '8px',
borderRadius: '18px',
});
return buttonDiv;
}
function buildChannelSubButton(channelHandle) {
let channelSubButton = document.createElement('span');
channelSubButton.innerText = 'Checking...';
channelSubButton.title = `TA Subscribe: ${channelHandle}`;
channelSubButton.setAttribute('data-id', channelHandle);
channelSubButton.setAttribute('data-type', 'channel');
channelSubButton.addEventListener('click', e => {
e.preventDefault();
if (channelSubButton.innerText === 'Subscribe') {
console.log(`subscribe to: ${channelHandle}`);
sendUrl(channelHandle, 'subscribe', channelSubButton);
} else if (channelSubButton.innerText === 'Unsubscribe') {
console.log(`unsubscribe from: ${channelHandle}`);
sendUrl(channelHandle, 'unsubscribe', channelSubButton);
} else {
console.log('Unknown state');
}
});
Object.assign(channelSubButton.style, {
padding: '5px',
cursor: 'pointer',
});
checkChannelSubscribed(channelSubButton);
return channelSubButton;
}
function checkChannelSubscribed(channelSubButton) {
function handleResponse(message) {
if (!message || (typeof message === 'object' && message.channel_subscribed === false)) {
channelSubButton.innerText = 'Subscribe';
} else if (typeof message === 'object' && message.channel_subscribed === true) {
channelSubButton.innerText = 'Unsubscribe';
} else {
console.log('Unknown state');
}
}
function handleError(e) {
buttonError(channelSubButton);
channelSubButton.innerText = 'Error';
console.error('error', e);
}
let channelHandle = channelSubButton.dataset.id;
let message = { type: 'getChannel', channelHandle };
let sending = sendMessage(message);
sending.then(handleResponse, handleError);
}
function buildSpacer() {
let spacer = document.createElement('span');
spacer.innerText = '|';
return spacer;
}
function buildChannelDownloadButton() {
let channelDownloadButton = document.createElement('span');
let currentLocation = window.location.href;
let urlObj = new URL(currentLocation);
if (urlObj.pathname.startsWith('/watch')) {
let params = new URLSearchParams(document.location.search);
let videoId = params.get('v');
channelDownloadButton.setAttribute('data-type', 'video');
channelDownloadButton.setAttribute('data-id', videoId);
channelDownloadButton.title = `TA download video: ${videoId}`;
checkVideoExists(channelDownloadButton);
} else {
channelDownloadButton.setAttribute('data-id', currentLocation);
channelDownloadButton.setAttribute('data-type', 'channel');
channelDownloadButton.title = `TA download channel ${currentLocation}`;
}
channelDownloadButton.innerHTML = downloadIcon;
channelDownloadButton.addEventListener('click', e => {
e.preventDefault();
console.log(`download: ${currentLocation}`);
sendDownload(channelDownloadButton);
});
Object.assign(channelDownloadButton.style, {
filter: 'invert()',
width: '20px',
padding: '0 5px',
cursor: 'pointer',
});
return channelDownloadButton;
}
function getTitleContainers() {
let elements = document.querySelectorAll('#video-title');
let videoNodes = [];
elements.forEach(element => {
if (isElementVisible(element)) {
videoNodes.push(element);
}
});
return elements;
}
function getVideoId(titleContainer) {
if (!titleContainer) return undefined;
let href = getNearestLink(titleContainer);
if (!href) return;
let videoId;
if (href.startsWith('/watch?v')) {
let params = new URLSearchParams(href);
videoId = params.get('/watch?v');
} else if (href.startsWith('/shorts/')) {
videoId = href.split('/')[2];
}
return videoId;
}
function buildVideoButton(titleContainer) {
let videoId = getVideoId(titleContainer);
if (!videoId) return;
const dlButton = document.createElement('a');
dlButton.classList.add('ta-button');
dlButton.href = '#';
Object.assign(dlButton.style, {
display: 'flex',
alignItems: 'center',
justifyContent: 'center',
backgroundColor: '#00202f',
color: '#fff',
fontSize: '1.4rem',
textDecoration: 'none',
borderRadius: '8px',
cursor: 'pointer',
height: 'fit-content',
opacity: 0,
});
let dlIcon = document.createElement('span');
dlIcon.innerHTML = defaultIcon;
Object.assign(dlIcon.style, {
filter: 'invert()',
width: '15px',
height: '15px',
padding: '7px 8px',
});
dlButton.appendChild(dlIcon);
dlButton.addEventListener('click', e => {
e.preventDefault();
sendDownload(dlButton);
e.stopPropagation();
});
return dlButton;
}
function getNearestLink(element) {
for (let i = 0; i < 5 && element && element !== document; i++) {
if (element.tagName === 'A' && element.getAttribute('href') !== '#') {
return element.getAttribute('href');
}
element = element.parentNode;
}
return null;
}
function getNearestH3(element) {
for (let i = 0; i < 5 && element && element !== document; i++) {
if (element.tagName === 'H3') {
return element;
}
element = element.parentNode;
}
return null;
}
function processTitle(titleContainer) {
if (titleContainer.hasListener) return;
Object.assign(titleContainer.style, {
display: 'flex',
gap: '15px',
});
titleContainer.classList.add('title-container');
titleContainer.addEventListener('mouseenter', () => {
const taButton = titleContainer.querySelector('.ta-button');
if (!taButton) return;
if (!taButton.isChecked) checkVideoExists(taButton);
taButton.style.opacity = 1;
});
titleContainer.addEventListener('mouseleave', () => {
const taButton = titleContainer.querySelector('.ta-button');
if (!taButton) return;
taButton.style.opacity = 0;
});
titleContainer.hasListener = true;
}
function checkVideoExists(taButton) {
function handleResponse(message) {
let buttonSpan = taButton.querySelector('span') || taButton;
if (message !== false) {
buttonSpan.innerHTML = checkmarkIcon;
buttonSpan.title = 'Open in TA';
buttonSpan.addEventListener('click', () => {
let win = window.open(message, '_blank');
win.focus();
});
} else {
buttonSpan.innerHTML = downloadIcon;
}
taButton.isChecked = true;
}
function handleError(e) {
buttonError(taButton);
let videoId = taButton.dataset.id;
console.log(`error: failed to get info from TA for video ${videoId}`);
console.error(e);
}
let aElem = taButton?.parentElement?.querySelector('a');
let videoId = getVideoId(aElem);;
if (aElem) {
taButton.setAttribute('data-id', videoId);
taButton.setAttribute('data-type', 'video');
taButton.title = `TA download video: ${taButton.parentElement.innerText} [${videoId}]`;
}
let message = { type: 'videoExists', videoId };
let sending = sendMessage(message);
sending.then(handleResponse, handleError);
}
function sendDownload(button) {
let url = button.dataset.id;
if (!url) return;
sendUrl(url, 'download', button);
}
function buttonError(button) {
let buttonSpan = button.querySelector('span');
if (buttonSpan === null) {
buttonSpan = button;
}
buttonSpan.style.filter =
'invert(19%) sepia(93%) saturate(7472%) hue-rotate(359deg) brightness(105%) contrast(113%)';
buttonSpan.style.color = 'red';
button.style.opacity = 1;
button.addEventListener('mouseout', () => {
Object.assign(button.style, {
opacity: 1,
});
});
}
function buttonSuccess(button) {
let buttonSpan = button.querySelector('span');
if (buttonSpan === null) {
buttonSpan = button;
}
if (buttonSpan.innerHTML === 'Subscribe') {
buttonSpan.innerHTML = 'Success';
setTimeout(() => {
buttonSpan.innerHTML = 'Unsubscribe';
}, 2000);
} else {
buttonSpan.innerHTML = checkmarkIcon;
}
}
function sendUrl(url, action, button) {
function handleResponse(message) {
console.log('sendUrl response: ' + JSON.stringify(message));
if (message === null || message.detail === 'Invalid token.') {
buttonError(button);
} else {
buttonSuccess(button);
}
}
function handleError(e) {
console.log('error', e);
buttonError(button);
}
let message = { type: action, url };
console.log('youtube link: ' + JSON.stringify(message));
let sending = sendMessage(message);
sending.then(handleResponse, handleError);
}
async function sendMessage(message) {
let { success, value } = await browserType.runtime.sendMessage(message);
if (!success) {
throw value;
}
return value;
}
function cleanButtons() {
console.log('trigger clean buttons');
document.querySelectorAll('.ta-button').forEach(button => {
button.parentElement.hasTA = false;
button.remove();
});
document.querySelectorAll('.ta-channel-button').forEach(button => {
button.parentElement.hasTA = false;
button.remove();
});
}
let oldHref = document.location.href;
function throttled(callback, time) {
let throttleBlock = false;
let lastArgs;
return (...args) => {
lastArgs = args;
if (throttleBlock) return;
throttleBlock = true;
setTimeout(() => {
throttleBlock = false;
callback(...lastArgs);
}, time);
};
}
let observer = new MutationObserver(list => {
const currentHref = document.location.href;
if (currentHref !== oldHref) {
cleanButtons();
oldHref = currentHref;
}
if (list.some(i => i.type === 'childList' && i.addedNodes.length > 0)) {
ensureTALinks();
}
});
observer.observe(document.body, { attributes: false, childList: true, subtree: true });