const LANGUAGES = {
	ar: "اَلْعَرَبِيَّةُ",
	be: "Беларуская мова",
	bn: "বাংলা",
	ca: "Català",
	cs: "Čeština",
	cy: "Cymraeg",
	da: "Dansk",
	de: "Deutch",
	dsb: "",
	en_US: "English (US)",
	eo: "Esperanto",
	es: "Español",
	eu: "",
	fa: "فارسی",
	fi: "Suomi",
	fr_FR: "Français",
	gd: "Gàidhlig",
	gl: "Galego",
	he: "עברית‎",
	hr: "Hrvatski",
	hu: "Magyar nyelv",
	id: "bahasa Indonesia",
	it: "Italiano",
	ja: "日本語",
	kab: "",
	kn: "",
	ko: "한국어",
	nl: "Nederlands",
	nn: "Norsk Nynorsk",
	oc: "Occitan",
	pl: "Polski",
	pt_BR: "Português brasileiro",
	pt: "Português",
	ru: "Русский язык",
	sl: "Slovenščina",
	sv: "Svenska",
	th: "ภาษาไทย",
	tr: "Türkçe",
	tt: "",
	zh_Hans: "简体字",
	zh_Hant: "繁體字"
};
const LANG_FALLBACK = "en_US";

class Context {
	lang;
	langMessages;
	langLoaded;
	ready;

	init() {
		if (this.initialized) {
			return;
		}
		var lang = sessionStorage.getItem("lang");
		if (lang && LANGUAGES[lang]) {
			var newLang = sessionStorage.getItem("newLang");
			if (newLang && LANGUAGES[newLang]) {
				this.lang = newLang;
				sessionStorage.removeItem("newLang");
				this.loadLanguage();
			} else {
				this.lang = lang;
				this.loadLanguage();
			}
		} else {
			var languages = navigator.languages;
			var found = false;
			for (var i = 0; i < languages.length; i++) {
				var lang = languages[i].replace("-", "_");
				if (LANGUAGES[lang]) {
					this.lang = lang;
					this.loadLanguage();
					found = true;
					break;
				}
			}
			if (!found) {
				this.lang = LANG_FALLBACK;
				this.loadLanguage();
			}
		}
		var user = sessionStorage.getItem("user");
		if (user) {
			var rawUser = JSON.parse(user);
			this.user = User.fromData(rawUser.host, rawUser.data);
		}
		var hostConfig = sessionStorage.getItem("host");
		if (hostConfig) {
			var rawConfig = JSON.parse(hostConfig);
			this.hostConfig = HostConfig.fromData(rawConfig.host, rawConfig.data);
		}
		this.initialized = true;
	}
	loadLanguage() {
		if (this.langMessages) {
			return;
		}
		var lang = this.lang;
		if (!LANGUAGES[lang]) {
			lang = LANG_FALLBACK;
		}
		// Use <script>, XHR request is likely to be blocked by CORS locally
		var script = document.createElement("script");
		script.setAttribute("type", "text/javascript");
		script.setAttribute("src", "res/locale/" + this.lang + ".js");
		document.getElementsByTagName("head")[0].appendChild(script);
		return true;
	}
	switchLanguage(newLang) {
		sessionStorage.setItem("newLang", newLang);
	}
	setMessages(dict) {
		this.langMessages = dict;
		sessionStorage.setItem("lang", this.lang);
		this.langLoaded = true;
		this.checkReady();
	}
	checkReady() {
		if (this.langLoaded && this.page) {
			this.page.boot();
		}
	}
	setPage(page) {
		this.page = page;
		this.checkReady();
	}
	setUser(user) {
		this.user = user;
		if (user !== null) {
			sessionStorage.setItem("user", JSON.stringify(this.user));
		} else {
			sessionStorage.removeItem("user");
		}
	}
	getUser() {
		return this.user;
	}
	setHostConfig(hostConfig) {
		this.hostConfig = hostConfig;
		if (hostConfig !== null) {
			sessionStorage.setItem("host", JSON.stringify(this.hostConfig));
		} else {
			sessionStorage.removeItem("host");
		}
	}
	getHostConfig() {
		return this.hostConfig;
	}
}

const CTX = new Context();

/**
 * Traduki mesaĝo por ordinaran tekston.
 */
function t(message, replacements = {}) {
	if (CTX.lang && CTX.langMessages[message]) {
		var msg = CTX.langMessages[message];
		Object.keys(replacements).forEach(key => {
			msg = msg.replaceAll("{" + key + "}", replacements[key]);
		});
		return msg;
	}
	return message;
}

/**
 * Traduki mesaĝo por HTML-trajton.
 */
function ta(message, replacements = {}) {
	return t(message, replacements).replace(/"/g, "&quot;");
}

/**
 * Traduki la nomon de la rolo.
 * @param role La rolo por traduki.
 * @return La tradukita nomo por la rolo. La angla vorto en la okaso se
 * la tradukito ne eksistas.
 */
function trole(role) {
	if (role === ROLE.ADMINISTRATOR) {
		return t("Administrator");
	} else if (role === ROLE.MODERATOR) {
		return t("Moderator");
	} else {
		return role;
	}
}