evcc-io/assets/js/theme.js
Michael Geers a3aba01adc
Add manual dark/light switch (#3901)
* Add manual dark/light switch

* Improve color theme labels
2022-08-01 10:15:27 +02:00

57 lines
1.5 KiB
JavaScript

const darkModeMatcher = window.matchMedia("(prefers-color-scheme: dark)");
const THEME_AUTO = "auto";
const THEME_LIGHT = "light";
const THEME_DARK = "dark";
export const THEMES = [THEME_AUTO, THEME_LIGHT, THEME_DARK];
const LOCAL_STORAGE_KEY = "theme";
export function getThemePreference() {
try {
const theme = window.localStorage[LOCAL_STORAGE_KEY];
if (THEMES.includes(theme)) {
return theme;
}
} catch (e) {
console.error("unable to read theme from localStorage", e);
}
return THEME_AUTO;
}
export function setThemePreference(theme) {
console.log({ theme });
if (!THEMES.includes(theme)) {
return;
}
try {
window.localStorage[LOCAL_STORAGE_KEY] = theme;
updateTheme();
} catch (e) {
console.error("unable to write theme to localStorage", e);
}
}
function updateTheme() {
let theme = getThemePreference();
if (theme === THEME_AUTO) {
theme = darkModeMatcher.matches ? THEME_DARK : THEME_LIGHT;
}
// update iOS title bar color
const themeColors = { light: "#f3f3f7", dark: "#020318" };
document.querySelector("meta[name=theme-color]").setAttribute("content", themeColors[theme]);
// toggle the class on html root
const $html = document.querySelector(":root");
$html.classList.add("no-transitions");
$html.classList.toggle("dark", theme === THEME_DARK);
window.requestAnimationFrame(function () {
$html.classList.remove("no-transitions");
});
}
export function watchThemeChanges() {
darkModeMatcher.addEventListener("change", updateTheme);
updateTheme();
}