TelegramPWA/src/util/switchTheme.ts
2025-10-14 03:23:20 +02:00

109 lines
3.3 KiB
TypeScript

import type { ThemeKey } from '../types';
import { requestMutation } from '../lib/fasterdom/fasterdom';
import themeColors from '../styles/themes.json';
import { animate } from './animation';
import { hex2rgbaObj, lerpRgbaObj } from './colors.ts';
let isInitialized = false;
const DECIMAL_PLACES = 3;
const DURATION_MS = 200;
const ENABLE_ANIMATION_DELAY_MS = 500;
const RGB_VARIABLES = new Set([
'--color-text',
'--color-primary-shade',
'--color-text-secondary',
'--color-accent-own',
]);
const DISABLE_ANIMATION_CSS = `
.no-animations #root *,
.no-animations #root *::before,
.no-animations #root *::after {
transition: none !important;
}`;
const colors = (Object.keys(themeColors) as Array<keyof typeof themeColors>).map((property) => ({
property,
colors: [hex2rgbaObj(themeColors[property][0]), hex2rgbaObj(themeColors[property][1])],
}));
const injectCss = (css: string) => {
const style = document.createElement('style');
style.textContent = css;
document.head.appendChild(style);
return () => {
document.head.removeChild(style);
};
};
const switchTheme = (theme: ThemeKey, withAnimation: boolean) => {
const themeClassName = `theme-${theme}`;
if (document.documentElement.classList.contains(themeClassName)) {
return;
}
const isDarkTheme = theme === 'dark';
const shouldAnimate = isInitialized && withAnimation;
const startIndex = isDarkTheme ? 0 : 1;
const endIndex = isDarkTheme ? 1 : 0;
const startAt = Date.now();
const themeColorTag = document.querySelector('meta[name="theme-color"]');
requestMutation(() => {
document.documentElement.classList.remove(`theme-${isDarkTheme ? 'light' : 'dark'}`);
let uninjectCss: (() => void) | undefined;
if (isInitialized) {
uninjectCss = injectCss(DISABLE_ANIMATION_CSS);
document.documentElement.classList.add('no-animations');
}
document.documentElement.classList.add(themeClassName);
if (themeColorTag) {
themeColorTag.setAttribute('content', isDarkTheme ? '#212121' : '#fff');
}
setTimeout(() => {
requestMutation(() => {
uninjectCss?.();
document.documentElement.classList.remove('no-animations');
});
}, ENABLE_ANIMATION_DELAY_MS);
isInitialized = true;
if (shouldAnimate) {
animate(() => {
const t = Math.min((Date.now() - startAt) / DURATION_MS, 1);
applyColorAnimationStep(startIndex, endIndex, transition(t));
return t < 1;
}, requestMutation);
} else {
applyColorAnimationStep(startIndex, endIndex);
}
});
};
function transition(t: number) {
return 1 - ((1 - t) ** 3.5);
}
function applyColorAnimationStep(startIndex: number, endIndex: number, interpolationRatio: number = 1) {
colors.forEach(({ property, colors: propertyColors }) => {
const {
r, g, b, a,
} = lerpRgbaObj(propertyColors[startIndex], propertyColors[endIndex], interpolationRatio);
const roundedA = a !== undefined ? Math.round((a / 255) * 10 ** DECIMAL_PLACES) / 10 ** DECIMAL_PLACES : undefined;
document.documentElement.style.setProperty(property, `rgb(${r},${g},${b}${roundedA ? `,${roundedA}` : ''})`);
if (RGB_VARIABLES.has(property)) {
document.documentElement.style.setProperty(`${property}-rgb`, `${r},${g},${b}`);
}
});
}
export default switchTheme;