☰

SE Preview on hover

Shows preview of the linked questions/answers on hover

目前为 2017-02-13 提交的版本。查看 最新版本。

  1. // ==UserScript==
  2. // @name           SE Preview on hover
  3. // @description    Shows preview of the linked questions/answers on hover
  4. // @version        0.0.7
  5. // @author         wOxxOm
  6. // @namespace      wOxxOm.scripts
  7. // @license        MIT License
  8. // @match          *://*.stackoverflow.com/*
  9. // @match          *://*.superuser.com/*
  10. // @match          *://*.serverfault.com/*
  11. // @match          *://*.askubuntu.com/*
  12. // @match          *://*.stackapps.com/*
  13. // @match          *://*.mathoverflow.net/*
  14. // @match          *://*.stackexchange.com/*
  15. // @require        https://greasyfork.org/scripts/12228/code/setMutationHandler.js
  16. // @grant          GM_addStyle
  17. // @grant          GM_xmlhttpRequest
  18. // @connect        stackoverflow.com
  19. // @connect        superuser.com
  20. // @connect        serverfault.com
  21. // @connect        askubuntu.com
  22. // @connect        stackapps.com
  23. // @connect        mathoverflow.net
  24. // @connect        stackexchange.com
  25. // @connect        cdn.sstatic.net
  26. // @run-at         document-end
  27. // @noframes
  28. // ==/UserScript==
  29.  
  30. /* jshint lastsemic:true, multistr:true, laxbreak:true, -W030, -W041, -W084 */
  31.  
  32. const PREVIEW_DELAY = 100;
  33. const COLORS = {
  34. 	question: {
  35. 		back: '80, 133, 195',
  36. 		fore: '#265184',
  37. 	},
  38. 	answer: {
  39. 		back: '112, 195, 80',
  40. 		fore: '#3f7722',
  41. 	},
  42. };
  43.  
  44. let xhr;
  45. let preview;
  46. let previewLink;
  47. let previewTimer;
  48. let previewCSScache = {};
  49. let hovering = {stoppedAt: {x:0, y:0}};
  50.  
  51. const rx = getURLregexForMatchedSites();
  52. const thisPageUrls = getPageBaseUrls(location.href);
  53. const stylesOverride = initStyles();
  54.  
  55. initPolyfills();
  56. setMutationHandler('a', onLinkAdded, {processExisting: true});
  57.  
  58. /**************************************************************/
  59.  
  60. function onLinkAdded(links) {
  61. 	for (let i = 0, link; (link = links[i++]); ) {
  62. 		if (isLinkPreviewable(link)) {
  63. 			link.removeAttribute('title');
  64. 			link.addEventListener('mouseover', onLinkHovered);
  65. 		}
  66. 	}
  67. }
  68.  
  69. function onLinkHovered(e) {
  70. 	if (e.ctrlKey || e.altKey || e.shiftKey || e.metaKey)
  71. 		return;
  72. 	previewLink = this;
  73. 	previewLink.addEventListener('mousemove', onLinkMouseMove);
  74. 	previewLink.addEventListener('mouseout', abortPreview);
  75. 	previewLink.addEventListener('mousedown', abortPreview);
  76. 	restartPreviewTimer();
  77. }
  78.  
  79. function onLinkMouseMove(e) {
  80. 	if (Math.abs(hovering.stoppedAt.x - e.clientX) < 2 && Math.abs(hovering.stoppedAt.y - e.clientY) < 2)
  81. 		return;
  82. 	hovering.stoppedAt.x = e.clientX;
  83. 	hovering.stoppedAt.y = e.clientY;
  84. 	restartPreviewTimer();
  85. }
  86.  
  87. function restartPreviewTimer() {
  88. 	clearTimeout(previewTimer);
  89. 	previewTimer = setTimeout(() => {
  90. 		previewTimer = 0;
  91. 		if (previewLink.matches(':hover'))
  92. 			downloadPreview(previewLink.href);
  93. 	}, PREVIEW_DELAY);
  94. }
  95.  
  96. function abortPreview() {
  97. 	previewLink.removeEventListener('mousemove', onLinkMouseMove);
  98. 	previewLink.removeEventListener('mouseout', abortPreview);
  99. 	previewLink.removeEventListener('mousedown', abortPreview);
  100. 	clearTimeout(previewTimer);
  101. 	previewTimer = setTimeout(() => {
  102. 		previewTimer = 0;
  103. 		if (preview && !preview.matches(':hover'))
  104. 			hideAndRemove(preview);
  105. 	}, 1000);
  106. 	if (xhr)
  107. 		xhr.abort();
  108. }
  109.  
  110. function hideAndRemove(element, transition) {
  111. 	if (transition) {
  112. 		element.style.transition = typeof transition == 'number' ? `opacity ${transition}s ease-in-out` : transition;
  113. 		return setTimeout(hideAndRemove, 0, element);
  114. 	}
  115. 	element.style.opacity = 0;
  116. 	element.addEventListener('transitionend', function remove() {
  117. 		element.removeEventListener('transitionend', remove);
  118. 		element.remove();
  119. 	});
  120. }
  121.  
  122. function downloadPreview(url) {
  123. 	xhr = GM_xmlhttpRequest({
  124. 		method: 'GET',
  125. 		url: url,
  126. 		onload: showPreview,
  127. 	});
  128. }
  129.  
  130. function showPreview(data) {
  131. 	let doc = new DOMParser().parseFromString(data.responseText, 'text/html');
  132. 	if (!doc || !doc.head) {
  133. 		console.error(GM_info.script.name, 'empty document received:', data);
  134. 		return;
  135. 	}
  136.  
  137. 	if (!$(doc, 'base'))
  138. 		doc.head.insertAdjacentHTML('afterbegin', `<base href="${data.finalUrl}">`);
  139.  
  140. 	let answerIdMatch = data.finalUrl.match(/questions\/.+?\/(\d+)/);
  141. 	let postId = answerIdMatch ? '#answer-' + answerIdMatch[1] : '#question';
  142. 	let post = $(doc, postId + ' .post-text');
  143. 	if (!post)
  144. 		return;
  145. 	let title = $(doc, 'meta[property="og:title"]').content;
  146. 	let comments = $(doc, `${postId} .comments`);
  147. 	let commentsMore = +$(comments, 'tbody').dataset.remainingCommentsCount && $(doc, `${postId} .js-show-link.comments-link`);
  148. 	let answers; // = answerIdMatch ? null : $$(doc, '.answer');
  149.  
  150. 	$$remove(doc, 'script, .post-menu');
  151.  
  152. 	let externalsReady = [stylesOverride];
  153. 	let stylesToGet = new Set();
  154. 	let afterBodyHtml = '';
  155.  
  156. 	fetchExternals();
  157. 	maybeRender();
  158.  
  159. 	function fetchExternals() {
  160. 		let codeBlocks = $$(post, 'pre code');
  161. 		if (codeBlocks.length) {
  162. 			codeBlocks.forEach(e => e.parentElement.classList.add('prettyprint'));
  163. 			externalsReady.push(
  164. 				'<script> StackExchange = {}; </script>',
  165. 				'<script src="https://cdn.sstatic.net/Js/prettify-full.en.js"></script>'
  166. 			);
  167. 			afterBodyHtml = '<script> prettyPrint(); </script>';
  168. 		}
  169.  
  170. 		$$(doc, 'style, link[rel="stylesheet"]').forEach(e => {
  171. 			if (e.localName == 'style')
  172. 				externalsReady.push(e.outerHTML);
  173. 			else if (e.href in previewCSScache)
  174. 				externalsReady.push(previewCSScache[e.href]);
  175. 			else {
  176. 				stylesToGet.add(e.href);
  177. 				GM_xmlhttpRequest({
  178. 					method: 'GET',
  179. 					url: e.href,
  180. 					onload: data => {
  181. 						externalsReady.push(previewCSScache[e.href] = '<style>' + data.responseText + '</style>');
  182. 						stylesToGet.delete(e.href);
  183. 						maybeRender();
  184. 					},
  185. 				});
  186. 			}
  187. 		});
  188.  
  189. 	}
  190.  
  191. 	function maybeRender() {
  192. 		if (stylesToGet.size)
  193. 			return;
  194. 		if (!preview) {
  195. 			preview = document.createElement('iframe');
  196. 			preview.id = 'SEpreview';
  197. 		}
  198. 		preview.classList.toggle('SEpreviewIsAnswer', !!answerIdMatch);
  199. 		document.body.appendChild(preview);
  200.  
  201. 		let bodyHtml = [post.parentElement, comments, commentsMore].map(e => e ? e.outerHTML : '').join('');
  202. 		let allHtml = `<head>${externalsReady.join('')}</head>
  203. 			<body${answerIdMatch ? ' class="SEpreviewIsAnswer"' : ''}>
  204. 				<a id="SEpreviewTitle" href="${data.finalUrl}">${title}</a>
  205. 				<div id="SEpreviewBody">${bodyHtml}</div>
  206. 				${!answers ? '' : '<div id="SEpreviewAnswers">' + answers.length + ' answer' + (answers.length > 1 ? 's' : '') + '</div>'}
  207. 				${afterBodyHtml}
  208. 			</body>`;
  209. 		try {
  210. 			let pvDoc = preview.contentDocument;
  211. 			pvDoc.open();
  212. 			pvDoc.write(allHtml);
  213. 			pvDoc.close();
  214. 		} catch(e) {
  215. 			preview.srcdoc = `<html>${allHtml}</html>`;
  216. 		}
  217. 		preview.contentWindow.onload = () => {
  218. 			preview.style.opacity = 1;
  219. 			let pvDoc = preview.contentDocument;
  220. 			pvDoc.addEventListener('mouseover', retainMainScrollPos);
  221. 			pvDoc.addEventListener('click', interceptLinks);
  222. 			if (answers)
  223. 				$(pvDoc, '#SEpreviewAnswers').addEventListener('click', revealAnswers);
  224. 		};
  225. 	}
  226.  
  227. 	function interceptLinks(e) {
  228. 		if (e.target.matches('.js-show-link.comments-link')) {
  229. 			hideAndRemove(e.target, 0.5);
  230. 			downloadComments();
  231. 		}
  232. 		else if (e.button || e.ctrlKey || e.altKey || e.shiftKey || e.metaKey)
  233. 			return;
  234. 		else if (isLinkPreviewable(e.target, getPageBaseUrls(previewLink.href)))
  235. 			downloadPreview(e.target.href);
  236. 		else
  237. 			return;
  238. 		e.preventDefault();
  239. 	}
  240.  
  241. 	function downloadComments() {
  242. 		GM_xmlhttpRequest({
  243. 			method: 'GET',
  244. 			url: new URL(data.finalUrl).origin + '/posts/' + comments.id.match(/\d+/)[0] + '/comments',
  245. 			onload: r => showComments(r.responseText),
  246. 		});
  247. 	}
  248.  
  249. 	function showComments(html) {
  250. 		let tbody = $(preview.contentDocument, `#${comments.id} tbody`);
  251. 		let oldIds = new Set([...tbody.rows].map(e => e.id));
  252. 		tbody.innerHTML = html;
  253. 		for (let tr of tbody.rows)
  254. 			if (!oldIds.has(tr.id))
  255. 				tr.classList.add('new-comment-highlight');
  256. 	}
  257. }
  258.  
  259. function retainMainScrollPos(e) {
  260. 	let scrollPos = {x:scrollX, y:scrollY};
  261. 	document.addEventListener('scroll', preventScroll);
  262. 	document.addEventListener('mouseover', releaseScrollLock);
  263.  
  264. 	function preventScroll(e) {
  265. 		scrollTo(scrollPos.x, scrollPos.y);
  266. 	}
  267. 	function releaseScrollLock(e) {
  268. 		document.removeEventListener('mouseout', releaseScrollLock);
  269. 		document.removeEventListener('scroll', preventScroll);
  270. 	}
  271. }
  272.  
  273. function getURLregexForMatchedSites() {
  274. 	return new RegExp('https?://(\\w*\\.)*(' + GM_info.script.matches.map(m =>
  275. 		m.match(/^.*?\/\/\W*(\w.*?)\//)[1].replace(/\./g, '\\.')
  276. 	).join('|') + ')/(questions|q|a)/\\d+');
  277. }
  278.  
  279. function getPageBaseUrls(url) {
  280. 	let base = (url.match(rx) || [])[0];
  281. 	return {
  282. 		base,
  283. 		short: base ? base.replace('/questions/', '/q/') : undefined,
  284. 	};
  285. }
  286.  
  287. function isLinkPreviewable(link, pageUrls = thisPageUrls) {
  288. 	return rx.test(link.href) &&
  289. 			!link.matches('.short-link') &&
  290. 			!link.href.startsWith(pageUrls.base) &&
  291. 			!link.href.startsWith(pageUrls.short);
  292. }
  293.  
  294. function $(node__optional, selector) {
  295. // or    $(selector) {
  296. 	return (node__optional || document).querySelector(selector || node__optional);
  297. }
  298.  
  299. function $$(node__optional, selector) {
  300. // or    $$(selector) {
  301. 	return (node__optional || document).querySelectorAll(selector || node__optional);
  302. }
  303.  
  304. function $$remove(node__optional, selector) {
  305. // or    $$remove(selector) {
  306. 	(node__optional || document).querySelectorAll(selector || node__optional)
  307. 		.forEach(e => e.remove());
  308. }
  309.  
  310. function initPolyfills() {
  311. 	NodeList.prototype.forEach = NodeList.prototype.forEach || Array.prototype.forEach;
  312. }
  313.  
  314. function initStyles() {
  315. 		GM_addStyle(`
  316. 		#SEpreview {
  317. 		    all: unset;
  318. 		    box-sizing: content-box;
  319. 		    width: 720px; /* 660px + 30px + 30px */
  320. 		    height: 33%;
  321. 		    min-height: 200px;
  322. 		    position: fixed;
  323. 		    opacity: 0;
  324. 		    transition: opacity .5s cubic-bezier(.88,.02,.92,.66);
  325. 		    right: 0;
  326. 		    bottom: 0;
  327. 		    padding: 0;
  328. 		    margin: 0;
  329. 		    background: white;
  330. 		    box-shadow: 0 0 100px rgba(0,0,0,0.5);
  331. 		    z-index: 999999;
  332. 		    border: 8px solid rgb(${COLORS.question.back});
  333. 		}
  334. 		#SEpreview.SEpreviewIsAnswer {
  335. 		    border-color: rgb(${COLORS.answer.back});
  336. 		}
  337. 	`);
  338.  
  339. 	return `<style>
  340. 		body, html {
  341. 			min-width: unset!important;
  342. 			box-shadow: none!important;
  343. 		}
  344. 		html, body {
  345. 			background: unset!important;;
  346. 		}
  347. 		body {
  348. 			display: flex;
  349. 			flex-direction: column;
  350. 			height: 100vh;
  351. 		}
  352. 		#SEpreviewTitle {
  353. 		    all: unset;
  354. 		    display: block;
  355. 		    padding: 20px 30px;
  356. 		    font-weight: bold;
  357. 		    font-size: 20px;
  358. 		    line-height: 1.3;
  359. 		    background-color: rgba(${COLORS.question.back}, 0.37);
  360. 		    color: ${COLORS.question.fore};
  361. 		}
  362. 		#SEpreviewTitle:hover {
  363. 		    text-decoration: underline;
  364. 		}
  365. 		#SEpreviewBody {
  366. 			padding: 30px!important;
  367. 			overflow: auto;
  368. 		}
  369. 		#SEpreviewBody::-webkit-scrollbar {
  370. 			background-color: rgba(${COLORS.question.back}, 0.1);
  371. 		}
  372. 		#SEpreviewBody::-webkit-scrollbar-thumb {
  373. 			background-color: rgba(${COLORS.question.back}, 0.2);
  374. 		}
  375. 		#SEpreviewBody::-webkit-scrollbar-thumb:hover {
  376. 			background-color: rgba(${COLORS.question.back}, 0.3);
  377. 		}
  378. 		#SEpreviewBody::-webkit-scrollbar-thumb:active {
  379. 			background-color: rgba(${COLORS.question.back}, 0.75);
  380. 		}
  381.  
  382. 		body.SEpreviewIsAnswer #SEpreviewTitle {
  383. 		    background-color: rgba(${COLORS.answer.back}, 0.37);
  384. 		    color: ${COLORS.answer.fore};
  385. 		}
  386. 		body.SEpreviewIsAnswer #SEpreviewBody::-webkit-scrollbar {
  387. 			background-color: rgba(${COLORS.answer.back}, 0.1);
  388. 		}
  389. 		body.SEpreviewIsAnswer #SEpreviewBody::-webkit-scrollbar-thumb {
  390. 			background-color: rgba(${COLORS.answer.back}, 0.2);
  391. 		}
  392. 		body.SEpreviewIsAnswer #SEpreviewBody::-webkit-scrollbar-thumb:hover {
  393. 			background-color: rgba(${COLORS.answer.back}, 0.3);
  394. 		}
  395. 		body.SEpreviewIsAnswer #SEpreviewBody::-webkit-scrollbar-thumb:active {
  396. 			background-color: rgba(${COLORS.answer.back}, 0.75);
  397. 		}
  398.  
  399. 		#SEpreviewAnswers {
  400. 			all: unset;
  401. 			display: block;
  402. 			padding: 10px 30px;
  403. 			font-weight: bold;
  404. 			font-size: 20px;
  405. 			line-height: 1.3;
  406. 			border-top: 4px solid rgba(${COLORS.answer.back}, 0.37);
  407. 			background-color: rgba(${COLORS.answer.back}, 0.37);
  408. 			color: ${COLORS.answer.fore};
  409. 		}
  410.  
  411. 		.comments .new-comment-highlight {
  412. 			-webkit-animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  413. 			-moz-animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  414. 			animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  415. 		}
  416.  
  417. 		@-webkit-keyframes highlight {
  418. 			from {background-color: #ffcf78}
  419. 			to   {background-color: none}
  420. 		}
  421. 	</style>`;
  422. }