stylus/js/dark-themer.js
2022-02-18 04:35:36 +03:00

34 lines
1.2 KiB
JavaScript

/* global $ */// dom.js
/* global API msg */// msg.js
'use strict';
/**
* This file must be loaded in a <script> tag placed after all the <link> tags
* that contain dark themes so that the stylesheets are loaded by the time this script runs.
* The CSS must use `@media screen and (prefers-color-scheme: dark), dark {}` that also works
* in old browsers and ensures CSS loads before the first paint, then we toggle the media here,
* which also happens before the first paint unless the browser "yields", but that's abnormal
* and not even a problem in the most popular case of using system dark/light mode.
*/
API.colorScheme.shouldIncludeStyle('darkUI').then(val => {
let isDark = val;
toggleDarkStyles();
msg.onExtension(e => {
if (e.method === 'colorScheme') {
isDark = e.value;
toggleDarkStyles();
}
});
function toggleDarkStyles() {
$.root.dataset.uiTheme = isDark ? 'dark' : 'light';
for (const sheet of document.styleSheets) {
for (const {media: m} of sheet.cssRules) {
if (m && m[1] === 'dark' && /screen/.test(m[0]) !== isDark) {
m.mediaText = isDark ? 'screen,dark' : 'not all,dark';
}
}
}
}
});