Greasy Fork is available in English.
獲取影片封面！
// ==UserScript==
// @name Youtube 封面
// @name:en Youtube Cover
// @name:zh-CN Youtube 封面
// @namespace http://tampermonkey.net/
// @version 1.4.1
// @description 獲取影片封面！
// @description:en Get the cover of youtube video！
// @description:zh-CN 获取视频封面！
// @author Anong0u0
// @match *://*.youtube.com/*
// @icon https://www.google.com/s2/favicons?sz=64&domain=youtube.com
// @grant GM_setValue
// @grant GM_getValue
// @noframes
// @license MIT License
// ==/UserScript==
const delay = (ms = 0) => {return new Promise((r)=>{setTimeout(r, ms)})}
const waitElementLoad = (elementSelector, selectCount = 1, tryTimes = 1, interval = 0) =>
{
return new Promise(async (resolve, reject)=>
{
let t = 1, result;
while(true)
{
if(selectCount != 1) {if((result = document.querySelectorAll(elementSelector)).length >= selectCount) break;}
else {if(result = document.querySelector(elementSelector)) break;}
if(tryTimes>0 && ++t>tryTimes) return reject(new Error("Wait Timeout"));
await delay(interval);
}
resolve(result);
})
}
Node.prototype.getXY = function ()
{
let x = 0, y = 0, element = this;
while (element)
{
x += element.offsetLeft - element.scrollLeft + element.clientLeft;
y += element.offsetTop - element.scrollLeft + element.clientTop;
element = element.offsetParent;
}
return {X: x, Y: y}
}
const checkImg = async (url) =>
{
return await fetch(url, { method: "HEAD" })
.then(response => response.ok)
.catch(() => false)
}
const main = () =>
{
const div = document.createElement("div");
div.style.marginLeft = "3em";
div.innerHTML =`
<!-- css -->
<style>
#ytCover {
text-decoration: none;
font-size: 2em;
font-weight: bold;
font-family: Roboto, Arial, sans-serif;
color: var(--yt-spec-text-primary);
}
div.list {
background-color: var(--yt-spec-brand-background-primary);
border: 1px solid var(--yt-spec-10-percent-layer);
padding: 0.5em 0;
position: fixed;
z-index: 114514;
max-height: 40em;
font-size: 10px
}
.linkBtn {
text-decoration: none;
}
.list-item {
text-align: center;
font-size: 1.5em;
color: var(--yt-spec-text-primary);
background-color: var(--yt-spec-brand-background-primary);
height: 2.5em;
line-height: 2.5em;
}
.list-item:hover {
background: #AAA;
box-shadow: 0 4px 5px rgba(0, 0, 0, 0.2);
}
.slide {
cursor: default
}
img#preview {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
z-index: 2000;
max-width: 100vw;
max-height: 65vh;
min-width: 40vw;
border: 3px solid #FFF;
}
.list > button {
border: none;
padding: unset;
width: inherit;
cursor: pointer;
}
</style>
<!-- html -->
<div>
<div class="slide" id="ytCover"></div>
<div class="list" id="ytListHead" style="border-top: none; top: 4.8em; left: 19em;" hidden>
<div class="list-item slide">1280x720+
<div class="list" style="border-left: none; width: 11.5em" hidden>
<a class="linkBtn" imgTag="maxresdefault"><div class="list-item">maxresdefault</div></a>
<a class="linkBtn" imgTag="maxres1"><div class="list-item">maxres1</div></a>
<a class="linkBtn" imgTag="maxres2"><div class="list-item">maxres2</div></a>
<a class="linkBtn" imgTag="maxres3"><div class="list-item">maxres3</div></a>
</div>
</div>
<div class="list-item slide">640x480
<div class="list" style="border-left: none; width: 8.5em" hidden>
<a class="linkBtn" imgTag="sddefault"><div class="list-item">sddefault</div></a>
<a class="linkBtn" imgTag="sd1"><div class="list-item">sd1</div></a>
<a class="linkBtn" imgTag="sd2"><div class="list-item">sd2</div></a>
<a class="linkBtn" imgTag="sd3"><div class="list-item">sd3</div></a>
</div>
</div>
<div class="list-item slide">480x360
<div class="list" style="border-left: none; width: 8.5em" hidden>
<a class="linkBtn" imgTag="hqdefault"><div class="list-item">hqdefault</div></a>
<a class="linkBtn" imgTag="hq1"><div class="list-item">hq1</div></a>
<a class="linkBtn" imgTag="hq2"><div class="list-item">hq2</div></a>
<a class="linkBtn" imgTag="hq3"><div class="list-item">hq3</div></a>
</div>
</div>
<div class="list-item slide">320x180
<div class="list" style="border-left: none; width: 8.5em" hidden>
<a class="linkBtn" imgTag="mqdefault"><div class="list-item">mqdefault</div></a>
<a class="linkBtn" imgTag="mq1"><div class="list-item">mq1</div></a>
<a class="linkBtn" imgTag="mq2"><div class="list-item">mq2</div></a>
<a class="linkBtn" imgTag="mq3"><div class="list-item">mq3</div></a>
</div>
</div>
<div class="list-item slide">120x90
<div class="list" style="border-left: none; width: 6.5em" hidden>
<a class="linkBtn" imgTag="default"><div class="list-item">default</div></a>
<a class="linkBtn" imgTag="1"><div class="list-item">1</div></a>
<a class="linkBtn" imgTag="2"><div class="list-item">2</div></a>
<a class="linkBtn" imgTag="3"><div class="list-item">3</div></a>
</div>
</div>
<button class="list-item">: <span id="previewSpan" style="font-weight: bold;">On</span></button>
</div>
</div>`
document.querySelector("#start").append(div);
const ytC = document.querySelector("#ytCover");
const ytLH = document.querySelector("#ytListHead");
const Lang = { cover: {en:"Cover", tc:"封面", sc:"封面"},
preview: {en:"Preview", tc:"圖片預覽", sc:"图片预览"},
on: {en:"On", tc:"開", sc:"开"},
off: {en:"Off", tc:"關", sc:"关"}};
const usedLang = document.querySelector("html").lang.match(/zh/) ?
(document.querySelector("html").lang.match(/CN/) ? "sc":"tc") : "en"
ytC.innerText = Lang.cover[usedLang];
ytLH.style.width = usedLang=="en"?"10em":"10.4em";
window.onresize = () =>
{
ytLH.style.left = (ytC.getXY().X/10-1)+"em";
if(window.innerWidth<1350)
{
if(window.innerWidth>850)div.style.marginLeft = 3*((window.innerWidth-500)/850) + "em";
else div.style.marginLeft = "1em";
}
else
{div.style.marginLeft = "3em"}
}
document.querySelectorAll(".list > .slide").forEach((e)=>
{
const list = e.querySelector(".list");
e.onmouseenter = () =>
{
list.style.top = (e.getXY().Y/10-0.5)+"em";
list.style.left = parseFloat(ytLH.style.left) + parseFloat(ytLH.style.width) + "em";
list.hidden = false;
};
e.onmouseleave = () => {list.hidden = true}
});
const preview = document.createElement("img");
preview.id = "preview";
preview.hidden = true;
document.body.append(preview);
const Btns = document.querySelectorAll(".linkBtn");
Btns.forEach((e)=>
{
e.onmouseenter = () =>
{
if(!GM_getValue("previewOn")) return;
preview.hidden = false;
preview.src = e.href;
};
e.onmouseleave = () => {preview.hidden = true}
e.target="_blank";
});
const previewBtn = document.querySelector(".list > button");
previewBtn.innerHTML = Lang.preview[usedLang] + previewBtn.innerHTML;
const previewSpan = document.querySelector("#previewSpan");
const previewBtnChange = () =>
{
if (GM_getValue("previewOn"))
{
previewSpan.style.color = "green";
previewSpan.innerText = Lang.on[usedLang];
}
else
{
previewSpan.style.color = "red";
previewSpan.innerText = Lang.off[usedLang];
}
};
previewBtn.onclick = () =>
{
GM_setValue("previewOn", !GM_getValue("previewOn"));
previewBtnChange();
}
previewBtnChange();
let hide;
ytC.onmouseenter = () =>
{
hide = false;
ytLH.hidden = false;
};
ytC.onmouseleave = () =>
{
hide = true;
delay(500).then(()=>{ytLH.hidden = hide});
};
ytLH.onmouseenter = () =>
{
hide = false;
};
ytLH.onmouseleave = () =>
{
hide = true;
delay(200).then(()=>{ytLH.hidden = hide});
};
let oldHref;
const onPageUpdate = () =>
{
if (oldHref == location.href) return
oldHref = location.href
console.log("[Youtube Cover] detect page updated")
const video_id = location.href.match(/(?<=v=)[^&]{11}/);
ytC.hidden = !video_id;
if (!video_id) return;
document.querySelectorAll(".list-item > .list").forEach((e)=>
{
e.parentNode.hidden = true;
e.querySelectorAll(".linkBtn").forEach((forEachBtn)=>
{
checkImg(`https://i.ytimg.com/vi/${video_id}/${forEachBtn.getAttribute("imgTag")}.jpg`).then((notHide)=>
{
forEachBtn.hidden = !notHide;
if(notHide) e.parentNode.hidden = false;
});
forEachBtn.href = `https://i.ytimg.com/vi/${video_id}/${forEachBtn.getAttribute("imgTag")}.jpg`
});
});
}
document.addEventListener("yt-rendererstamper-finished", onPageUpdate)
document.addEventListener("yt-page-type-changed", onPageUpdate)
document.addEventListener("yt-navigate-start", onPageUpdate)
waitElementLoad("yt-page-navigation-progress",1,20,250)
.then((e)=>{new MutationObserver(onPageUpdate).observe(e, {attributes: true})})
console.log("[Youtube Cover] done");
}
console.log("[Youtube Cover] loading");
waitElementLoad("#start", 1, 10, 300).then(main)