/**
 * Copyright © Volker Schukai and all contributing authors, {{copyRightYear}}. All rights reserved.
 * Node module: @schukai/monster
 *
 * This source code is licensed under the GNU Affero General Public License version 3 (AGPLv3).
 * The full text of the license can be found at: https://www.gnu.org/licenses/agpl-3.0.en.html
 *
 * For those who do not wish to adhere to the AGPLv3, a commercial license is available.
 * Acquiring a commercial license allows you to use this software without complying with the AGPLv3 terms.
 * For more information about purchasing a commercial license, please contact Volker Schukai.
 */

import { instanceSymbol } from "../../constants.mjs";
import { addAttributeToken } from "../../dom/attributes.mjs";
import {
	ATTRIBUTE_ERRORMESSAGE,
	ATTRIBUTE_ROLE,
} from "../../dom/constants.mjs";
import { CustomControl } from "../../dom/customcontrol.mjs";
import {
	CustomElement,
	updaterTransformerMethodsSymbol,
} from "../../dom/customelement.mjs";
import {
	assembleMethodSymbol,
	registerCustomElement,
} from "../../dom/customelement.mjs";
import { findTargetElementFromEvent } from "../../dom/events.mjs";
import { isFunction, isObject } from "../../types/is.mjs";
import { LocalePickerStyleSheet } from "./stylesheet/locale-picker.mjs";
import { fireCustomEvent } from "../../dom/events.mjs";
import { detectUserLanguagePreference } from "../../i18n/util.mjs";
import { Formatter } from "../../text/formatter.mjs";

import "../form/button.mjs";
import "../form/select.mjs";

export { LocalePicker };

/**
 * @private
 * @type {symbol}
 * Reference to the main picker element
 */
const localePickerElementSymbol = Symbol("localePickerElement");

/**
 * @private
 * @type {symbol}
 * Reference to the other languages select element
 */
const otherLanguagesElementSymbol = Symbol("otherLanguagesElement");

/**
 * @private
 * @type {symbol}
 * Reference to the language button element
 */
const buttonLanguageElementSymbol = Symbol("buttonLanguageElement");

/**
 * @private
 * @type {symbol}
 * Reference to the 'no thanks' button element
 */
const buttonNoThanksElementSymbol = Symbol("buttonNoThanksElement");

/**
 * @private
 * @type {symbol}
 * Stores detected languages
 */
const detectedLanguagesSymbol = Symbol("detectedLanguages");

/**
 * A LocalePicker
 *
 * @fragments /fragments/components/accessibility/locale-picker/
 *
 * @example /examples/components/accessibility/locale-picker-simple Simple example
 * @example /examples/components/accessibility/locale-picker-reset Reset Selection
 *
 * @issue https://localhost.alvine.dev:8440/development/issues/closed/276.html
 *
 * @since 3.97.0
 * @copyright Volker Schukai
 * @summary A locale picker for choosing and resetting language decisions in multilingual interfaces.
 */
class LocalePicker extends CustomElement {
	/**
	 * This method is called by the `instanceof` operator.
	 * @returns {symbol}
	 */
	static get [instanceSymbol]() {
		return Symbol.for(
			"@schukai/monster/components/accessibility/locale-picker@@instance",
		);
	}

	/**
	 * Initializes the component.
	 * @return {LocalePicker}
	 */
	[assembleMethodSymbol]() {
		super[assembleMethodSymbol]();
		initControlReferences.call(this);
		initEventHandler.call(this);

		return this;
	}

	/**
	 * To set the options via the HTML Tag, the attribute `data-monster-options` must be used.
	 * @see {@link https://monsterjs.org/en/doc/#configurate-a-monster-control}
	 *
	 * The individual configuration values can be found in the table.
	 *
	 * @property {Object} templates Template definitions
	 * @property {string} templates.main Main template
	 * @property {Object} labels Label definitions
	 * @property {string} labels.headline Headline
	 * @property {string} labels.text Text
	 * @property {string} labels.button-label Button label
	 * @property {string} labels.button-no-thanks Button no thanks
	 * @property {string} labels.headline-other Headline other languages
	 * @property {Function} callbacks.getTranslation Callback to get the translation for the labels
	 * @property {Object} features Features
	 * @property {boolean} features.removeOnSelected Remove the element when a language is selected
	 * @property {boolean} features.showAlways Show the element always
	 * @property {boolean} disabled Disabled state
	 */
	get defaults() {
		return Object.assign({}, super.defaults, {
			templates: {
				main: getTemplate(),
			},
			labels: {
				headline: "Welcome to our Website",
				text: "This page is currently displayed in ${currentLabel}. However, we also offer this page in your preferred language. Would you like to switch?",
				"button-label": "Switch to ${preferred.label}",
				"button-no-thanks": "No, thanks",
				"headline-other": "Other languages",
			},

			callbacks: {
				getTranslation: getTranslations,
			},

			disabled: false,
			features: {
				removeOnSelected: false,
				showAlways: false,
			},
		});
	}

	/**
	 * Private method that provides a mapping of transformer methods keyed by their names.
	 * These transformer methods define custom transformations for given input values.
	 *
	 * @private
	 * @return {Object} An object containing transformer methods for internal use.
	 */
	[updaterTransformerMethodsSymbol]() {
		return {
			"replace-placeholder": (value) => {
				const formatter = new Formatter(this[detectedLanguagesSymbol]);
				return formatter.format(value);
			},
		};
	}

	/**
	 * Lifecycle method that is called when the custom element is appended into a document-connected element.
	 * Invokes the parent class's connectedCallback method and retrieves the user's preferred language.
	 * Hides or shows the picker depending on the user's language and stored session.
	 *
	 * @return {void}
	 */
	connectedCallback() {
		super.connectedCallback();

		this[detectedLanguagesSymbol] = detectUserLanguagePreference();

		if (
			!isObject(this[detectedLanguagesSymbol]?.preferred) &&
			this.getOption("features.showAlways") !== true
		) {
			this.hide();

			if (this.getOption("features.removeOnSelected")) {
				this.remove();
			}
			return;
		}

		if (!isObject(this[detectedLanguagesSymbol]?.preferred)) {
			this[detectedLanguagesSymbol].preferred = {
				fullLang: "en",
				baseLang: "en",
				label: "English",
			};
		}

		const stored = sessionStorage.getItem(buildStorageKey.call(this));
		if (stored && this.getOption("features.showAlways") !== true) {
			if (this.getOption("features.removeOnSelected")) {
				this.remove();
			}
			return;
		}

		this.show();

		if (
			this[otherLanguagesElementSymbol] instanceof HTMLElement &&
			this[detectedLanguagesSymbol].offerable &&
			this[detectedLanguagesSymbol].offerable.length > 1
		) {
			this[otherLanguagesElementSymbol].classList.remove("hidden");
			this[otherLanguagesElementSymbol].setOption(
				"mapping.labelTemplate",
				"${label}",
			);
			this[otherLanguagesElementSymbol].setOption(
				"mapping.valueTemplate",
				"${href}",
			);
			this[otherLanguagesElementSymbol].importOptions(
				this[detectedLanguagesSymbol]?.offerable || [],
			);
		}

		if (
			this[detectedLanguagesSymbol].offerable &&
			this[detectedLanguagesSymbol].offerable.length > 0
		) {
			const getTranslationCallback = this.getOption("callbacks.getTranslation");
			if (isFunction(getTranslationCallback)) {
				const translations = getTranslationCallback(
					this[detectedLanguagesSymbol].offerable[0].baseLang,
				);

				this.setOption("labels", translations.labels);
				if (this[otherLanguagesElementSymbol]) {
					this[otherLanguagesElementSymbol].setOption(
						"labels.select-an-option",
						translations.selectAnOption,
					);
				}
			}
		}
	}

	/**
	 * Resets the locale picker by removing the stored value from the local storage.
	 *
	 * @returns {LocalePicker}
	 */
	reset() {
		sessionStorage.removeItem(buildStorageKey.call(this));
		this.show();
		return this;
	}

	/**
	 * Hides the locale picker.
	 *
	 * @returns {LocalePicker}
	 */
	hide() {
		this.style.display = "none";

		if (!this[localePickerElementSymbol]) {
			return this;
		}

		this[localePickerElementSymbol].style.display = "none";
		return this;
	}

	/**
	 * Shows the locale picker.
	 * @returns {LocalePicker}
	 */
	show() {
		this.style.display = "block";

		if (!this[localePickerElementSymbol]) {
			return this;
		}

		this[localePickerElementSymbol].style.display = "block";
		return this;
	}

	/**
	 * @return {string}
	 */
	static getTag() {
		return "monster-locale-picker";
	}

	/**
	 * @return {CSSStyleSheet[]}
	 */
	static getCSSStyleSheet() {
		return [LocalePickerStyleSheet];
	}
}

/**
 * @private
 * @return {void}
 * Initializes references to all relevant elements in the picker.
 */
function initControlReferences() {
	this[localePickerElementSymbol] = this.shadowRoot.querySelector(
		`[${ATTRIBUTE_ROLE}="control"]`,
	);

	this[otherLanguagesElementSymbol] = this.shadowRoot.querySelector(
		`[${ATTRIBUTE_ROLE}="other-languages"]`,
	);

	this[buttonNoThanksElementSymbol] = this.shadowRoot.querySelector(
		`[${ATTRIBUTE_ROLE}="button-no-thanks"]`,
	);

	this[buttonLanguageElementSymbol] = this.shadowRoot.querySelector(
		`[${ATTRIBUTE_ROLE}="button-language"]`,
	);
}

/**
 * @private
 * @return {initEventHandler}
 * Initializes all event handlers for the picker.
 */
function initEventHandler() {
	const self = this;
	const element = this[localePickerElementSymbol];

	const type = "click";

	element.addEventListener(type, function (event) {
		const callback = self.getOption("actions.click");

		fireCustomEvent(self, "monster-locale-picker-clicked", {
			element: self,
		});

		if (!isFunction(callback)) {
			return;
		}

		const element = findTargetElementFromEvent(
			event,
			ATTRIBUTE_ROLE,
			"control",
		);

		if (!(element instanceof Node && self.hasNode(element))) {
			return;
		}

		callback.call(self, event);
	});

	this[buttonNoThanksElementSymbol].setOption("actions.click", () => {
		sessionStorage.setItem(buildStorageKey.call(this), "1");
		this.hide();
		if (this.getOption("features.removeOnSelected")) {
			this.remove();
		}
	});

	this[buttonLanguageElementSymbol].setOption("actions.click", () => {
		sessionStorage.setItem(buildStorageKey.call(this), "1");
		window.location.href = this[detectedLanguagesSymbol].offerable?.[0]?.href;
	});

	this[otherLanguagesElementSymbol].addEventListener("change", (event) => {
		const element = findTargetElementFromEvent(
			event,
			ATTRIBUTE_ROLE,
			"other-languages",
		);

		if (element) {
			const selected = element?.value;
			if (selected) {
				sessionStorage.setItem(buildStorageKey.call(this), "1");
				window.location.href = selected;
			}
		}
	});

	return this;
}

/**
 * @private
 * @returns {string}
 * Builds the session storage key for the picker.
 */
function buildStorageKey() {
	return "locale-picker-" + this[detectedLanguagesSymbol].current;
}

/**
 * @private
 * @param lang
 * @returns {Object}
 * Returns translations for the given language.
 */
function getTranslations(lang) {
	const map = {
		en: {
			headline: "Welcome to our Website",
			text: "This page is currently displayed in ${currentLabel}. However, we also offer this page in your preferred language. Would you like to switch?",
			"button-label": "Switch to ${preferred.label}",
			"button-no-thanks": "No, thanks",
			"headline-other": "Other languages",
		},
		de: {
			headline: "Willkommen auf unserer Webseite",
			text: "Diese Seite wird aktuell auf ${currentLabel} angezeigt. Wir bieten jedoch auch diese Seite in Ihrer bevorzugten Sprache an. Möchten Sie wechseln?",
			"button-label": "Wechseln zu ${preferred.label}",
			"button-no-thanks": "Nein, danke",
			"headline-other": "Andere Sprachen",
		},
		fr: {
			headline: "Bienvenue sur notre site web",
			text: "Cette page est actuellement affichée en ${currentLabel}. Cependant, nous proposons également cette page dans votre langue préférée. Souhaitez-vous changer?",
			"button-label": "Changer pour ${preferred.label}",
			"button-no-thanks": "Non, merci",
			"headline-other": "Autres langues",
		},
		es: {
			headline: "Bienvenido a nuestro sitio web",
			text: "Esta página se muestra actualmente en ${currentLabel}. Sin embargo, también ofrecemos esta página en su idioma preferido. ¿Le gustaría cambiar?",
			"button-label": "Cambiar a ${preferred.label}",
			"button-no-thanks": "No, gracias",
			"headline-other": "Otros idiomas",
		},
		it: {
			headline: "Benvenuti sul nostro sito web",
			text: "Questa pagina è attualmente visualizzata in ${currentLabel}. Tuttavia, offriamo anche questa pagina nella tua lingua preferita. Vuoi cambiare?",
			"button-label": "Cambia nella ${preferred.label}",
			"button-no-thanks": "No, grazie",
			"headline-other": "Altre lingue",
		},
		pt: {
			headline: "Bem-vindo ao nosso site",
			text: "Esta página está atualmente exibida em ${currentLabel}. No entanto, também oferecemos esta página no seu idioma preferido. Gostaria de mudar?",
			"button-label": "Mudar para ${preferred.label}",
			"button-no-thanks": "Não, obrigado",
			"headline-other": "Outros idiomas",
		},
		nl: {
			headline: "Welkom op onze website",
			text: "Deze pagina wordt momenteel weergegeven in ${currentLabel}. We bieden deze pagina echter ook aan in uw voorkeurstaal. Wilt u overschakelen?",
			"button-label": "Overschakelen naar ${preferred.label}",
			"button-no-thanks": "Nee, bedankt",
			"headline-other": "Andere talen",
		},
		pl: {
			headline: "Witamy na naszej stronie",
			text: "Ta strona jest obecnie wyświetlana po ${currentLabel}. Oferujemy jednak również tę stronę w Twoim preferowanym języku. Czy chcesz przełączyć?",
			"button-label": "Przełącz na ${preferred.label}",
			"button-no-thanks": "Nie, dziękuję",
			"headline-other": "Inne języki",
		},
		ru: {
			headline: "Добро пожаловать на наш сайт",
			text: "Эта страница в настоящее время отображается на ${currentLabel}. Однако мы также предлагаем эту страницу на вашем предпочтительном языке. Хотите переключиться?",
			"button-label": "Переключиться на ${preferred.label}",
			"button-no-thanks": "Нет, спасибо",
			"headline-other": "Другие языки",
		},
		cs: {
			headline: "Vítejte na našem webu",
			text: "Tato stránka je aktuálně zobrazena v ${currentLabel}. Nabízíme však tuto stránku také ve vašem preferovaném jazyce. Chcete přejít?",
			"button-label": "Přejít na ${preferred.label}",
			"button-no-thanks": "Ne, děkuji",
			"headline-other": "Další jazyky",
		},
		sk: {
			headline: "Vitajte na našej webovej stránke",
			text: "Táto stránka je v súčasnosti zobrazená v ${currentLabel}. Ponúkame však túto stránku aj vo vašom preferovanom jazyku. Chcete prejsť?",
			"button-label": "Prepnúť na ${preferred.label}",
			"button-no-thanks": "Nie, ďakujem",
			"headline-other": "Iné jazyky",
		},

		bg: {
			headline: "Добре дошли на нашия уебсайт",
			text: "Тази страница в момента се показва на ${currentLabel}. Въпреки това, предлагаме също тази страница на Вашия предпочитан език. Желаете ли да превключите?",
			"button-label": "Превключете на ${preferred.label}",
			"button-no-thanks": "Не, благодаря",
			"headline-other": "Други езици",
		},
		hr: {
			headline: "Dobrodošli na našu web stranicu",
			text: "Ova stranica trenutno je prikazana na ${currentLabel}. Međutim, nudimo i ovu stranicu na vašem preferiranom jeziku. Želite li prebaciti?",
			"button-label": "Prebaci na ${preferred.label}",
			"button-no-thanks": "Ne, hvala",
			"headline-other": "Drugi jezici",
		},
		fi: {
			headline: "Tervetuloa verkkosivustollemme",
			text: "Tämä sivu on tällä hetkellä näkyvissä ${currentLabel}. Tarjoamme kuitenkin tätä sivua myös suosimallasi kielellä. Haluaisitko vaihtaa?",
			"button-label": "Vaihda ${preferred.label}",
			"button-no-thanks": "Ei kiitos",
			"headline-other": "Muut kielet",
		},
		sv: {
			headline: "Välkommen till vår webbplats",
			text: "Denna sida visas för närvarande på ${currentLabel}. Vi erbjuder dock även denna sida på ditt föredragna språk. Skulle du vilja byta?",
			"button-label": "Byt till ${preferred.label}",
			"button-no-thanks": "Nej tack",
			"headline-other": "Andra språk",
		},
		el: {
			headline: "Καλώς ήρθατε στην ιστοσελίδα μας",
			text: "Αυτή η σελίδα εμφανίζεται προς το παρόν στα ${currentLabel}. Ωστόσο, προσφέρουμε επίσης αυτή τη σελίδα στην προτιμώμενη γλώσσα σας. Θα θέλατε να αλλάξετε;",
			"button-label": "Αλλαγή σε ${preferred.label}",
			"button-no-thanks": "Όχι, ευχαριστώ",
			"headline-other": "Άλλες γλώσσες",
		},
		hu: {
			headline: "Üdvözöljük weboldalunkon",
			text: "Ez az oldal jelenleg ${currentLabel} nyelven jelenik meg. Azonban kínáljuk ezt az oldalt a preferált nyelvén is. Szeretne váltani?",
			"button-label": "Váltás ${preferred.label} nyelvre",
			"button-no-thanks": "Nem, köszönöm",
			"headline-other": "További nyelvek",
		},
		ro: {
			headline: "Bine ați venit pe site-ul nostru",
			text: "Această pagină este afișată în prezent în ${currentLabel}. Totuși, oferim de asemenea această pagină în limba dumneavoastră preferată. Doriți să schimbați?",
			"button-label": "Schimbați în ${preferred.label}",
			"button-no-thanks": "Nu, mulțumesc",
			"headline-other": "Alte limbi",
		},
		da: {
			headline: "Velkommen til vores hjemmeside",
			text: "Denne side vises i øjeblikket på ${currentLabel}. Vi tilbyder dog også denne side på dit foretrukne sprog. Vil du skifte?",
			"button-label": "Skift til ${preferred.label}",
			"button-no-thanks": "Nej tak",
			"headline-other": "Andre sprog",
		},
		no: {
			headline: "Velkommen til vår nettside",
			text: "Denne siden vises for øyeblikket på ${currentLabel}. Vi tilbyr imidlertid også denne siden på ditt foretrukne språk. Ønsker du å bytte?",
			"button-label": "Bytt til ${preferred.label}",
			"button-no-thanks": "Nei, takk",
			"headline-other": "Andre språk",
		},
		hi: {
			headline: "हमारी वेबसाइट पर आपका स्वागत है",
			text: "यह पृष्ठ वर्तमान में ${currentLabel} में प्रदर्शित हो रहा है। हालांकि, हम इस पृष्ठ को आपकी पसंदीदा भाषा में भी प्रदान करते हैं। क्या आप स्विच करना चाहेंगे?",
			"button-label": "${preferred.label} में स्विच करें",
			"button-no-thanks": "नहीं, धन्यवाद",
			"headline-other": "अन्य भाषाएँ",
		},
		bn: {
			headline: "আমাদের ওয়েবসাইটে আপনাকে স্বাগতম",
			text: "এই পৃষ্ঠাটি বর্তমানে ${currentLabel} প্রদর্শিত হচ্ছে। তবে, আমরা এই পৃষ্ঠাটি আপনার পছন্দের ভাষায়ও অফার করি। আপনি কি সুইচ করতে চান?",
			"button-label": "${preferred.label}-এ সুইচ করুন",
			"button-no-thanks": "না, ধন্যবাদ",
			"headline-other": "অন্যান্য ভাষাসমূহ",
		},
		ta: {
			headline: "எங்கள் இணையதளத்திற்கு வருக",
			text: "இந்த பக்கம் தற்போது ${currentLabel} என்ற மொழியில் காட்சியளிக்கப்படுகிறது. எனினும், நாங்கள் இந்த பக்கத்தை உங்கள் விருப்ப மொழியிலும் வழங்குகிறோம். நீங்கள் மாற்ற விரும்புகிறீர்களா?",
			"button-label": "${preferred.label}-க்கு மாற்றவும்",
			"button-no-thanks": "இல்லை, நன்றி",
			"headline-other": "மற்ற மொழிகள்",
		},
		te: {
			headline: "మా వెబ్‌సైట్‌కు స్వాగతం",
			text: "ఈ పేజీ ప్రస్తుతం ${currentLabel}లో ప్రదర్శితం అవుతున్నది. అయితే, మేము ఈ పేజీని మీ ఇష్టపడే భాషలో కూడా అందిస్తున్నాము. మీరు మార్చాలనుకుంటున్నారా?",
			"button-label": "${preferred.label}కి మార్చండి",
			"button-no-thanks": "కాదు, ధన్యవాదాలు",
			"headline-other": "ఇతర భాషలు",
		},
		mr: {
			headline: "आपले आमच्या वेबसाइटवर स्वागत आहे",
			text: "हे पान सध्या ${currentLabel}मध्ये दाखविले जात आहे. परंतु, आम्ही हे पान आपल्या पसंतीच्या भाषेतही देत आहोत. आपण स्विच करू इच्छिता का?",
			"button-label": "${preferred.label}मध्ये स्विच करा",
			"button-no-thanks": "नाही, धन्यवाद",
			"headline-other": "इतर भाषा",
		},
		zh: {
			headline: "欢迎访问我们的网站",
			text: "本页面当前显示为${currentLabel}。然而，我们还提供您偏好的语言版本。您想切换吗？",
			"button-label": "切换到${preferred.label}",
			"button-no-thanks": "不，谢谢",
			"headline-other": "其他语言",
		},
		ja: {
			headline: "私たちのウェブサイトへようこそ",
			text: "このページは現在${currentLabel}で表示されています。しかし、私たちはあなたの好みの言語でこのページを提供しています。切り替えますか？",
			"button-label": "${preferred.label}に切り替える",
			"button-no-thanks": "いいえ、結構です",
			"headline-other": "他の言語",
		},
	};

	const selectAnOption = {
		en: "Select a language",
		de: "Wählen Sie eine Sprache",
		fr: "Sélectionnez une langue",
		es: "Seleccione un idioma",
		it: "Seleziona una lingua",
		pt: "Selecione um idioma",
		nl: "Selecteer een taal",
		pl: "Wybierz język",
		ru: "Выберите язык",
		cs: "Vyberte jazyk",
		sk: "Vyberte jazyk",
		bg: "Изберете език",
		hr: "Odaberite jezik",
		fi: "Valitse kieli",
		sv: "Välj ett språk",
		el: "Επιλέξτε γλώσσα",
		hu: "Válasszon egy nyelvet",
		ro: "Selectați o limbă",
		da: "Vælg et sprog",
		no: "Velg et språk",
		hi: "एक भाषा चुनें",
		bn: "একটি ভাষা নির্বাচন করুন",
		ta: "ஒரு மொழியைத் தேர்ந்தெடுக்கவும்",
		te: "భాషను ఎంచుకోండి",
		mr: "एक भाषा निवडा",
		zh: "选择一种语言",
		ja: "言語を選択してください",
	};

	const result = {};

	if (map[lang]) {
		result["labels"] = map[lang];
	} else {
		result["labels"] = map["en"];
	}

	if (selectAnOption[lang]) {
		result["selectAnOption"] = selectAnOption[lang];
	} else {
		result["selectAnOption"] = selectAnOption["en"];
	}

	return result;
}

/**
 * @private
 * @return {string}
 * Returns the template for the component.
 */
function getTemplate() {
	// language=HTML
	return `
        <div data-monster-role="control" part="control">
            <h2 data-monster-role="headline" part="headline" data-monster-replace="path:labels.headline"></h2>
            <p part="text" data-monster-replace="path:labels.text | call:replace-placeholder"></p>
            <div data-monster-role="container" part="container">
                <monster-button data-monster-role="button-language" part="button-language"
                                data-monster-replace="path:labels.button-label | call:replace-placeholder"></monster-button>
                <monster-button data-monster-role="button-no-thanks" part="button-no-thanks" 
                                data-monster-replace="path:labels.button-no-thanks | call:replace-placeholder"></monster-button>
                <monster-select class="hidden" data-monster-role="other-languages"></monster-select>
            </div>
        </div>`;
}

registerCustomElement(LocalePicker);
