infoalloggi-monorepo/apps/infoalloggi/src/providers/I18nProvider.tsx

import {
	createContext,
	type FC,
	type ReactNode,
	useContext,
	useMemo,
} from "react";
import { en } from "~/i18n/en";
import { it } from "~/i18n/it";
import type { LangDict, Locales } from "~/i18n/locales";

type I18nContextType = {
	locale: Locales;
	t: LangDict;
};

const I18nContext = createContext<I18nContextType>({
	locale: "it",
	t: it,
});

export const I18nProvider: FC<{
	children: ReactNode;
	locale: string | undefined;
}> = ({ children, locale }) => {
	const contextValue = useMemo(() => {
		const validatedLocale = validateLocale(locale);
		return {
			locale: validatedLocale,
			t: validatedLocale === "en" ? en : it,
		};
	}, [locale]);
	return (
		<I18nContext.Provider value={contextValue}>{children}</I18nContext.Provider>
	);
};

export const useTranslation = () => {
	const value = useContext(I18nContext);
	if (!value) {
		throw new Error("useTranslation must be used within a I18nProvider");
	}
	return value;
};
const validateLocale = (locale: string | undefined): Locales => {
	if (locale === "en") return "en";
	return "it";
};