import { useEffect, useReducer, useMemo } from 'react';

import ExpoLocalization, {
  addCalendarListener,
  addLocaleListener,
  removeSubscription,
} from './ExpoLocalization';
import { Localization } from './Localization.types';
export * from './Localization.types';

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * Three-character ISO 4217 currency code. Returns `null` on web.
 *
 * @example
 * `'USD'`, `'EUR'`, `'CNY'`, `null`
 */
export const currency = ExpoLocalization.currency;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * Decimal separator used for formatting numbers.
 *
 * @example
 * `','`, `'.'`
 */
export const decimalSeparator = ExpoLocalization.decimalSeparator;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * Digit grouping separator used when formatting numbers larger than 1000.
 *
 * @example
 * `'.'`, `''`, `','`
 */
export const digitGroupingSeparator = ExpoLocalization.digitGroupingSeparator;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * A list of all the supported language ISO codes.
 */
export const isoCurrencyCodes = ExpoLocalization.isoCurrencyCodes;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * Boolean value that indicates whether the system uses the metric system.
 * On Android and web, this is inferred from the current region.
 */
export const isMetric = ExpoLocalization.isMetric;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * Returns if the system's language is written from Right-to-Left.
 * This can be used to build features like [bidirectional icons](https://material.io/design/usability/bidirectionality.html).
 *
 * Returns `false` in Server Side Rendering (SSR) environments.
 */
export const isRTL = ExpoLocalization.isRTL;

// @needsAudit
/**
 * @deprecated Use [`Localization.getLocales()`](#localizationgetlocales) instead.
 * An [IETF BCP 47 language tag](https://en.wikipedia.org/wiki/IETF_language_tag),
 * consisting of a two-character language code and optional script, region and variant codes.
 *
 * @example
 * `'en'`, `'en-US'`, `'zh-Hans'`, `'zh-Hans-CN'`, `'en-emodeng'`
 */
export const locale = ExpoLocalization.locale;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * List of all the native languages provided by the user settings.
 * These are returned in the order the user defines in their device settings.
 *
 * @example
 * `['en', 'en-US', 'zh-Hans', 'zh-Hans-CN', 'en-emodeng']`
 */
export const locales = ExpoLocalization.locales;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getCalendars() instead.
 * The current time zone in display format.
 * On Web time zone is calculated with Intl.DateTimeFormat().resolvedOptions().timeZone. For a
 * better estimation you could use the moment-timezone package but it will add significant bloat to
 * your website's bundle size.
 *
 * @example
 * `'America/Los_Angeles'`
 */
export const timezone = ExpoLocalization.timezone;

// @needsAudit
/**
 * @hidden
 * @deprecated Use Localization.getLocales() instead.
 * The region code for your device that comes from the Region setting under Language & Region on iOS.
 * This value is always available on iOS, but might return `null` on Android or web.
 *
 * @example
 * `'US'`, `'NZ'`, `null`
 */
export const region = ExpoLocalization.region;

/**
 * List of user's locales, returned as an array of objects of type `Locale`.
 * Guaranteed to contain at least 1 element.
 * These are returned in the order the user defines in their device settings.
 * On the web currency and measurements systems are not provided, instead returned as null.
 * If needed, you can infer them from the current region using a lookup table.
 * @example
 * ```js
 * [{
 *   "languageTag": "pl-PL",
 *   "languageCode": "pl",
 *   "textDirection": "ltr",
 *   "digitGroupingSeparator": " ",
 *   "decimalSeparator": ",",
 *   "measurementSystem": "metric",
 *   "currencyCode": "PLN",
 *   "currencySymbol": "zł",
 *   "regionCode": "PL",
 *   "temperatureUnit": "celsius"
 * }]
 * ```
 */
export const getLocales = ExpoLocalization.getLocales;

/**
 * List of user's preferred calendars, returned as an array of objects of type `Calendar`.
 * Guaranteed to contain at least 1 element.
 * For now always returns a single element, but it's likely to return a user preference list on some platforms in the future.
 * @example
 * ```js
 * [{
 *   "calendar": "gregory",
 *   "timeZone": "Europe/Warsaw",
 *   "uses24hourClock": true,
 *   "firstWeekday": 1
 * }]
 * ```
 */
export const getCalendars = ExpoLocalization.getCalendars;

/**
 * A hook providing a list of user's locales, returned as an array of objects of type `Locale`.
 * Guaranteed to contain at least 1 element.
 * These are returned in the order the user defines in their device settings.
 * On the web currency and measurements systems are not provided, instead returned as null.
 * If needed, you can infer them from the current region using a lookup table.
 * If the OS settings change, the hook will rerender with a new list of locales.
 * @example
 * ```js
 * [{
 *   "languageTag": "pl-PL",
 *   "languageCode": "pl",
 *   "textDirection": "ltr",
 *   "digitGroupingSeparator": " ",
 *   "decimalSeparator": ",",
 *   "measurementSystem": "metric",
 *   "currencyCode": "PLN",
 *   "currencySymbol": "zł",
 *   "regionCode": "PL",
 *   "temperatureUnit": "celsius"
 * }]
 * ```
 */
export function useLocales() {
  const [key, invalidate] = useReducer((k) => k + 1, 0);
  const locales = useMemo(() => getLocales(), [key]);
  useEffect(() => {
    const subscription = addLocaleListener(invalidate);
    return () => {
      removeSubscription(subscription);
    };
  }, []);
  return locales;
}

/**
 * A hook providing a list of user's preferred calendars, returned as an array of objects of type `Calendar`.
 * Guaranteed to contain at least 1 element.
 * For now always returns a single element, but it's likely to return a user preference list on some platforms in the future.
 * If the OS settings change, the hook will rerender with a new list of calendars.
 * @example
 * ```js
 * [{
 *   "calendar": "gregory",
 *   "timeZone": "Europe/Warsaw",
 *   "uses24hourClock": true,
 *   "firstWeekday": 1
 * }]
 * ```
 */
export function useCalendars() {
  const [key, invalidate] = useReducer((k) => k + 1, 0);
  const calendars = useMemo(() => getCalendars(), [key]);
  useEffect(() => {
    const subscription = addCalendarListener(invalidate);
    return () => {
      removeSubscription(subscription);
    };
  }, []);
  return calendars;
}

// @needsAudit
/**
 * @hidden
 * Get the latest native values from the device. Locale can be changed on some Android devices
 * without resetting the app.
 * > On iOS, changing the locale will cause the device to reset meaning the constants will always be
 * correct.
 *
 * @example
 * ```ts
 * // When the app returns from the background on Android...
 *
 * const { locale } = await Localization.getLocalizationAsync();
 * ```
 * @deprecated
 * Use Localization.getLocales() or Localization.getCalendars() instead.
 */
export async function getLocalizationAsync(): Promise<Localization> {
  return await ExpoLocalization.getLocalizationAsync();
}