/**
 * Locale-aware date/number formatting.
 *
 * The app ships English + Spanish, but `date-fns` calls `formatDistanceToNow`
 * with the default (English) locale and native `Date.toLocaleDateString()`
 * falls back to the *runtime* locale, not the app language. This module keeps a
 * single module-level locale in sync with `LanguageProvider` and re-exports all
 * of `date-fns` with `formatDistanceToNow` / `formatDistance` / `format`
 * overridden to apply it. Import from here instead of `date-fns` directly.
 *
 * `dateLocaleCode()` feeds native `toLocaleDateString/TimeString` calls so a
 * Spanish user sees "5 ene" rather than "Jan 5".
 */
export * from 'date-fns';

import {
  formatDistanceToNow as _formatDistanceToNow,
  formatDistanceToNowStrict as _formatDistanceToNowStrict,
  formatDistance as _formatDistance,
  format as _format,
} from 'date-fns';
import { enUS, es as esLocale, th as thLocale } from 'date-fns/locale';
import type { Locale } from 'date-fns';
import type { Language } from '@/contexts/language';

let activeLocale: Locale = enUS;
let activeCode = 'en-US';

/** Called by LanguageProvider (during render) so children format in-language. */
export function setDateLocale(language: Language): void {
  if (language === 'es') {
    activeLocale = esLocale;
    activeCode = 'es-ES';
  } else if (language === 'th') {
    activeLocale = thLocale;
    activeCode = 'th-TH';
  } else {
    activeLocale = enUS;
    activeCode = 'en-US';
  }
}

/** The active date-fns locale. */
export function dateLocale(): Locale {
  return activeLocale;
}

/** BCP-47 code for native `toLocale*` / `Intl` APIs. */
export function dateLocaleCode(): string {
  return activeCode;
}

type DistOptions = Parameters<typeof _formatDistanceToNow>[1];
type DistStrictOptions = Parameters<typeof _formatDistanceToNowStrict>[1];
type FormatDistanceOptions = Parameters<typeof _formatDistance>[2];
type FormatOptions = Parameters<typeof _format>[2];

export function formatDistanceToNow(date: Date | number, options?: DistOptions) {
  return _formatDistanceToNow(date, { ...options, locale: options?.locale ?? activeLocale });
}

export function formatDistanceToNowStrict(date: Date | number, options?: DistStrictOptions) {
  return _formatDistanceToNowStrict(date, { ...options, locale: options?.locale ?? activeLocale });
}

export function formatDistance(date: Date | number, baseDate: Date | number, options?: FormatDistanceOptions) {
  return _formatDistance(date, baseDate, { ...options, locale: options?.locale ?? activeLocale });
}

export function format(date: Date | number, formatStr: string, options?: FormatOptions) {
  return _format(date, formatStr, { ...options, locale: options?.locale ?? activeLocale });
}