stylus/content/apply.js
2019-03-03 08:29:26 -06:00

664 lines
19 KiB
JavaScript

/* eslint no-var: 0 */
/* global msg API prefs */
/* exported APPLY */
'use strict';
// some weird bug in new Chrome: the content script gets injected multiple times
// define a constant so it throws when redefined
const APPLY = (() => {
const CHROME = chrome.app ? parseInt(navigator.userAgent.match(/Chrom\w+\/(?:\d+\.){2}(\d+)|$/)[1]) : NaN;
const STYLE_VIA_API = !chrome.app && document instanceof XMLDocument;
var ID_PREFIX = 'stylus-';
var ROOT;
var isOwnPage = location.protocol.endsWith('-extension:');
var disableAll = false;
var styleElements = new Map();
var disabledElements = new Map();
var docRewriteObserver;
var docRootObserver;
const setStyleContent = createSetStyleContent();
const initializing = init();
msg.onTab(applyOnMessage);
if (!isOwnPage) {
window.dispatchEvent(new CustomEvent(chrome.runtime.id, {
detail: pageObject({method: 'orphan'})
}));
window.addEventListener(chrome.runtime.id, orphanCheck, true);
}
let parentDomain;
prefs.subscribe(['disableAll'], (key, value) => doDisableAll(value));
if (window !== parent) {
prefs.subscribe(['exposeIframes'], updateExposeIframes);
}
function init() {
if (STYLE_VIA_API) {
return API.styleViaAPI({method: 'styleApply'});
}
return API.getSectionsByUrl(getMatchUrl())
.then(result => {
ROOT = document.documentElement;
applyStyles(result, () => {
// CSS transition bug workaround: since we insert styles asynchronously,
// the browsers, especially Firefox, may apply all transitions on page load
if ([...styleElements.values()].some(n => n.textContent.includes('transition'))) {
applyTransitionPatch();
}
});
});
}
function pageObject(target) {
// https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Sharing_objects_with_page_scripts
const obj = new window.Object();
Object.assign(obj, target);
return obj;
}
function createSetStyleContent() {
// FF59+ bug workaround
// See https://github.com/openstyles/stylus/issues/461
// Since it's easy to spoof the browser version in pre-Quantum FF we're checking
// for getPreventDefault which got removed in FF59 https://bugzil.la/691151
const EVENT_NAME = chrome.runtime.id;
let ready;
return (el, content) =>
checkPageScript().then(ok => {
if (!ok) {
const disabled = el.disabled;
el.textContent = content;
el.disabled = disabled;
} else {
const detail = pageObject({
method: 'setStyleContent',
id: el.id,
content
});
window.dispatchEvent(new CustomEvent(EVENT_NAME, {detail}));
}
});
function checkPageScript() {
if (!ready) {
ready = CHROME || isOwnPage || Event.prototype.getPreventDefault ?
Promise.resolve(false) : injectPageScript();
}
return ready;
}
function injectPageScript() {
const scriptContent = EVENT_NAME => {
document.currentScript.remove();
const available = checkStyleApplied();
if (available) {
window.addEventListener(EVENT_NAME, function handler(e) {
const {method, id, content} = e.detail;
if (method === 'setStyleContent') {
const el = document.getElementById(id);
if (!el) {
return;
}
const disabled = el.disabled;
el.textContent = content;
el.disabled = disabled;
} else if (method === 'orphan') {
window.removeEventListener(EVENT_NAME, handler);
}
}, true);
}
window.dispatchEvent(new CustomEvent(EVENT_NAME, {detail: {
method: 'init',
available
}}));
function checkStyleApplied() {
const style = document.createElement('style');
style.textContent = ':root{--stylus-applied:1}';
document.documentElement.appendChild(style);
const applied = getComputedStyle(document.documentElement)
.getPropertyValue('--stylus-applied');
style.remove();
return Boolean(applied);
}
};
const code = `(${scriptContent})(${JSON.stringify(EVENT_NAME)})`;
const src = `data:application/javascript;base64,${btoa(code)}`;
const script = document.createElement('script');
const {resolve, promise} = deferred();
script.src = src;
script.onerror = resolveFalse;
window.addEventListener('error', resolveFalse);
window.addEventListener(EVENT_NAME, handleInit);
(document.head || document.documentElement).appendChild(script);
return promise.then(result => {
script.remove();
window.removeEventListener(EVENT_NAME, handleInit);
window.removeEventListener('error', resolveFalse);
return result;
});
function resolveFalse() {
resolve(false);
}
function handleInit(e) {
if (e.detail.method === 'init') {
resolve(e.detail.available);
}
}
}
}
function deferred() {
const o = {};
o.promise = new Promise((resolve, reject) => {
o.resolve = resolve;
o.reject = reject;
});
return o;
}
function getMatchUrl() {
var matchUrl = location.href;
if (!matchUrl.match(/^(http|file|chrome|ftp)/)) {
// dynamic about: and javascript: iframes don't have an URL yet
// so we'll try the parent frame which is guaranteed to have a real URL
try {
if (window !== parent) {
matchUrl = parent.location.href;
}
} catch (e) {}
}
return matchUrl;
}
function applyOnMessage(request) {
if (request.method === 'ping') {
return true;
}
if (STYLE_VIA_API) {
if (request.method === 'urlChanged') {
request.method = 'styleReplaceAll';
}
API.styleViaAPI(request);
return;
}
switch (request.method) {
case 'styleDeleted':
removeStyle(request.style);
break;
case 'styleUpdated':
if (request.codeIsUpdated === false) {
applyStyleState(request.style);
} else if (request.style.enabled) {
API.getSectionsByUrl(getMatchUrl(), request.style.id)
.then(sections => {
if (!sections[request.style.id]) {
removeStyle(request.style);
} else {
applyStyles(sections);
}
});
} else {
removeStyle(request.style);
}
break;
case 'styleAdded':
if (request.style.enabled) {
API.getSectionsByUrl(getMatchUrl(), request.style.id)
.then(applyStyles);
}
break;
case 'urlChanged':
API.getSectionsByUrl(getMatchUrl())
.then(replaceAll);
break;
case 'backgroundReady':
initializing
.catch(err => {
if (msg.RX_NO_RECEIVER.test(err.message)) {
return init();
}
})
.catch(console.error);
break;
case 'updateCount':
updateCount();
break;
}
}
function doDisableAll(disable = disableAll) {
if (!disable === !disableAll) {
return;
}
disableAll = disable;
if (STYLE_VIA_API) {
API.styleViaAPI({method: 'prefChanged', prefs: {disableAll}});
} else {
Array.prototype.forEach.call(document.styleSheets, stylesheet => {
if (stylesheet.ownerNode.matches(`style.stylus[id^="${ID_PREFIX}"]`)
&& stylesheet.disabled !== disable) {
stylesheet.disabled = disable;
}
});
}
}
function fetchParentDomain() {
if (parentDomain) {
return Promise.resolve();
}
return API.getTabUrlPrefix()
.then(newDomain => {
parentDomain = newDomain;
});
}
function updateExposeIframes() {
if (!prefs.get('exposeIframes') || window === parent || !styleElements.size) {
document.documentElement.removeAttribute('stylus-iframe');
} else {
fetchParentDomain().then(() => {
document.documentElement.setAttribute('stylus-iframe', parentDomain);
});
}
}
function updateCount() {
if (window !== parent) {
// we don't care about iframes
return;
}
if (/^\w+?-extension:\/\/.+(popup|options)\.html$/.test(location.href)) {
// popup and the option page are not tabs
return;
}
if (STYLE_VIA_API) {
API.styleViaAPI({method: 'updateCount'}).catch(msg.ignoreError);
return;
}
let count = 0;
for (const id of styleElements.keys()) {
if (!disabledElements.has(id)) {
count++;
}
}
// we have to send the tabId so we can't use `sendBg` that is used by `API`
msg.send({
method: 'invokeAPI',
name: 'updateIconBadge',
args: [count]
}).catch(console.error);
}
function applyStyleState({id, enabled}) {
const inCache = disabledElements.get(id) || styleElements.get(id);
const inDoc = document.getElementById(ID_PREFIX + id);
if (enabled) {
if (inDoc) {
return;
} else if (inCache) {
addStyleElement(inCache);
disabledElements.delete(id);
} else {
return API.getSectionsByUrl(getMatchUrl(), id)
.then(applyStyles);
}
} else {
if (inDoc) {
disabledElements.set(id, inDoc);
docRootObserver.evade(() => inDoc.remove());
}
}
updateCount();
}
function removeStyle({id}) {
const el = document.getElementById(ID_PREFIX + id);
if (el) {
docRootObserver.evade(() => el.remove());
}
disabledElements.delete(id);
if (styleElements.delete(id)) {
updateCount();
}
}
function applyStyles(sections, done) {
if (!Object.keys(sections).length) {
if (done) {
done();
}
return;
}
if (!document.documentElement) {
new MutationObserver((mutations, observer) => {
if (document.documentElement) {
observer.disconnect();
applyStyles(sections, done);
}
}).observe(document, {childList: true});
return;
}
if (docRootObserver) {
docRootObserver.stop();
} else {
initDocRootObserver();
}
const pending = [];
for (const section of Object.values(sections)) {
pending.push(applySections(section.id, section.code.join('')));
}
docRootObserver.firstStart();
if (!isOwnPage && !docRewriteObserver && styleElements.size) {
initDocRewriteObserver();
}
updateExposeIframes();
updateCount();
if (done) {
Promise.all(pending).then(done);
}
}
function applySections(id, code) {
let el = styleElements.get(id) || document.getElementById(ID_PREFIX + id);
if (el && CHROME < 3321) {
// workaround for Chrome devtools bug fixed in v65
el.remove();
el = null;
}
if (!el) {
if (document.documentElement instanceof SVGSVGElement) {
// SVG document style
el = document.createElementNS('http://www.w3.org/2000/svg', 'style');
} else if (document instanceof XMLDocument) {
// XML document style
el = document.createElementNS('http://www.w3.org/1999/xhtml', 'style');
} else {
// HTML document style; also works on HTML-embedded SVG
el = document.createElement('style');
}
el.id = ID_PREFIX + id;
el.type = 'text/css';
// SVG className is not a string, but an instance of SVGAnimatedString
el.classList.add('stylus');
addStyleElement(el);
}
let settingStyle;
if (el.textContent !== code) {
settingStyle = setStyleContent(el, code);
}
styleElements.set(id, el);
disabledElements.delete(id);
return Promise.resolve(settingStyle);
}
function addStyleElement(newElement) {
if (!ROOT) {
return;
}
let next;
const newStyleId = getStyleId(newElement);
for (const el of styleElements.values()) {
if (el.parentNode && !el.id.endsWith('-ghost') && getStyleId(el) > newStyleId) {
next = el.parentNode === ROOT ? el : null;
break;
}
}
if (next === newElement.nextElementSibling) {
return;
}
const insert = () => {
ROOT.insertBefore(newElement, next || null);
if (disableAll) {
newElement.disabled = true;
}
};
if (docRootObserver) {
docRootObserver.evade(insert);
} else {
insert();
}
}
function replaceAll(newStyles) {
const oldStyles = Array.prototype.slice.call(
document.querySelectorAll(`style.stylus[id^="${ID_PREFIX}"]`));
oldStyles.forEach(el => (el.id += '-ghost'));
styleElements.clear();
disabledElements.clear();
applyStyles(newStyles);
const removeOld = () => oldStyles.forEach(el => el.remove());
if (docRewriteObserver) {
docRootObserver.evade(removeOld);
} else {
removeOld();
}
}
function applyTransitionPatch() {
// CSS transition bug workaround: since we insert styles asynchronously,
// the browsers, especially Firefox, may apply all transitions on page load
const className = chrome.runtime.id + '-transition-bug-fix';
const docId = document.documentElement.id ? '#' + document.documentElement.id : '';
document.documentElement.classList.add(className);
applySections(0, `
${docId}.${CSS.escape(className)}:root * {
transition: none !important;
}
`)
.then(() => {
setTimeout(() => {
removeStyle({id: 0});
document.documentElement.classList.remove(className);
});
});
}
function getStyleId(el) {
return parseInt(el.id.substr(ID_PREFIX.length));
}
function orphanCheck(e) {
if (e && e.detail.method !== 'orphan') {
return;
}
if (chrome.i18n && chrome.i18n.getUILanguage()) {
return true;
}
// In Chrome content script is orphaned on an extension update/reload
// so we need to detach event listeners
[docRewriteObserver, docRootObserver].forEach(ob => ob && ob.disconnect());
window.removeEventListener(chrome.runtime.id, orphanCheck, true);
try {
msg.off(applyOnMessage);
} catch (e) {}
}
function initDocRewriteObserver() {
// detect documentElement being rewritten from inside the script
docRewriteObserver = new MutationObserver(mutations => {
for (let m = mutations.length; --m >= 0;) {
const added = mutations[m].addedNodes;
for (let n = added.length; --n >= 0;) {
if (added[n].localName === 'html') {
reinjectStyles();
return;
}
}
}
});
docRewriteObserver.observe(document, {childList: true});
// detect dynamic iframes rewritten after creation by the embedder i.e. externally
setTimeout(() => {
if (document.documentElement !== ROOT) {
reinjectStyles();
}
});
// re-add styles if we detect documentElement being recreated
function reinjectStyles() {
if (!styleElements) {
orphanCheck();
return;
}
ROOT = document.documentElement;
docRootObserver.stop();
const imported = [];
for (const [id, el] of styleElements.entries()) {
const copy = document.importNode(el, true);
el.textContent += ' '; // invalidate CSSOM cache
imported.push([id, copy]);
addStyleElement(copy);
}
docRootObserver.start();
styleElements = new Map(imported);
}
}
function initDocRootObserver() {
let lastRestorationTime = 0;
let restorationCounter = 0;
let observing = false;
let sorting = false;
let observer;
// allow any types of elements between ours, except for the following:
const ORDERED_TAGS = ['head', 'body', 'frameset', 'style', 'link'];
init();
return;
function init() {
observer = new MutationObserver(sortStyleElements);
docRootObserver = {firstStart, start, stop, evade, disconnect: stop};
setTimeout(sortStyleElements);
}
function firstStart() {
if (sortStyleMap()) {
sortStyleElements();
}
start();
}
function start() {
if (!observing && ROOT && observer) {
observer.observe(ROOT, {childList: true});
observing = true;
}
}
function stop() {
if (observing) {
observer.takeRecords();
observer.disconnect();
observing = false;
}
}
function evade(fn) {
const wasObserving = observing;
if (observing) {
stop();
}
fn();
if (wasObserving) {
start();
}
}
function sortStyleMap() {
const list = [];
let prevStyleId = 0;
let needsSorting = false;
for (const entry of styleElements.entries()) {
list.push(entry);
const el = entry[1];
const styleId = getStyleId(el);
el.styleId = styleId;
needsSorting |= styleId < prevStyleId;
prevStyleId = styleId;
}
if (needsSorting) {
styleElements = new Map(list.sort((a, b) => a[1].styleId - b[1].styleId));
return true;
}
}
function sortStyleElements() {
if (!observing) return;
let prevExpected = document.documentElement.lastElementChild;
while (prevExpected && isSkippable(prevExpected, true)) {
prevExpected = prevExpected.previousElementSibling;
}
if (!prevExpected) return;
for (const el of styleElements.values()) {
if (!isMovable(el)) {
continue;
}
while (true) {
const next = prevExpected.nextElementSibling;
if (next && isSkippable(next)) {
prevExpected = next;
} else if (
next === el ||
next === el.previousElementSibling && next ||
moveAfter(el, next || prevExpected)) {
prevExpected = el;
break;
} else {
return;
}
}
}
if (sorting) {
sorting = false;
if (observer) observer.takeRecords();
if (!restorationLimitExceeded()) {
start();
} else {
setTimeout(start, 1000);
}
}
}
function isMovable(el) {
return el.parentNode || !disabledElements.has(getStyleId(el));
}
function isSkippable(el, skipOwnStyles) {
return !ORDERED_TAGS.includes(el.localName) ||
el.id.startsWith(ID_PREFIX) &&
(skipOwnStyles || el.id.endsWith('-ghost')) &&
el.localName === 'style' &&
el.className === 'stylus';
}
function moveAfter(el, expected) {
if (!sorting) {
sorting = true;
stop();
}
expected.insertAdjacentElement('afterend', el);
if (el.disabled !== disableAll) {
// moving an element resets its 'disabled' state
el.disabled = disableAll;
}
return true;
}
function restorationLimitExceeded() {
const t = performance.now();
if (t - lastRestorationTime > 1000) {
restorationCounter = 0;
}
lastRestorationTime = t;
return ++restorationCounter > 5;
}
}
})();