nezha-dash-v1/src/components/ThemeProvider.tsx

import { createContext, type ReactNode, useEffect, useState } from "react";

export type Theme = "dark" | "light" | "system";

type ThemeProviderProps = {
	children: ReactNode;
	defaultTheme?: Theme;
	storageKey?: string;
};

type ThemeProviderState = {
	theme: Theme;
	setTheme: (theme: Theme) => void;
};

const initialState: ThemeProviderState = {
	theme: "system",
	setTheme: () => null,
};

const ThemeProviderContext = createContext<ThemeProviderState>(initialState);

export function ThemeProvider({
	children,
	storageKey = "vite-ui-theme",
}: ThemeProviderProps) {
	const [theme, setTheme] = useState<Theme>(
		() => (localStorage.getItem(storageKey) as Theme) || "system",
	);

	useEffect(() => {
		const root = window.document.documentElement;

		root.classList.add("disable-transitions");
		root.classList.remove("light", "dark");

		if (theme === "system") {
			const systemTheme = window.matchMedia("(prefers-color-scheme: dark)")
				.matches
				? "dark"
				: "light";

			root.classList.add(systemTheme);
			const themeColor =
				systemTheme === "dark" ? "hsl(30 15% 8%)" : "hsl(0 0% 98%)";
			document
				.querySelector('meta[name="theme-color"]')
				?.setAttribute("content", themeColor);
			const timeoutId = window.setTimeout(() => {
				root.classList.remove("disable-transitions");
			}, 0);
			return () => window.clearTimeout(timeoutId);
		}

		root.classList.add(theme);
		const themeColor = theme === "dark" ? "hsl(30 15% 8%)" : "hsl(0 0% 98%)";
		document
			.querySelector('meta[name="theme-color"]')
			?.setAttribute("content", themeColor);
		const timeoutId = window.setTimeout(() => {
			root.classList.remove("disable-transitions");
		}, 0);
		return () => window.clearTimeout(timeoutId);
	}, [theme]);

	const value = {
		theme,
		setTheme: (theme: Theme) => {
			localStorage.setItem(storageKey, theme);
			setTheme(theme);
		},
	};

	return (
		<ThemeProviderContext.Provider value={value}>
			{children}
		</ThemeProviderContext.Provider>
	);
}

export { ThemeProviderContext };