import type { H3Event } from 'h3';

import type { Config } from '~/locale/config.ts';
import type { PronounData, PronounExamplesData } from '~/locale/data.ts';
import { loadSuml, loadTsv } from '~/server/loader.ts';
import { parsePronounGroups, parsePronouns } from '~/src/buildPronoun.ts';
import { buildCalendar } from '~/src/calendar/calendar.ts';
import type { Calendar } from '~/src/calendar/helpers.ts';
import { PronounLibrary } from '~/src/classes.ts';
import type { Pronoun, PronounGroup } from '~/src/classes.ts';
import { getLocaleForUrl, getUrlForLocale } from '~/src/domain.ts';
import type { NounsData } from '~/src/nouns.ts';
import { Translator } from '~/src/translator.ts';

const setDefault = async <K, V>(map: Map<K, V>, key: K, supplier: () => Promise<V>): Promise<V> => {
    const value = map.get(key);
    if (value !== undefined) {
        return value;
    }
    const computedValue = await supplier();
    map.set(key, computedValue);
    return computedValue;
};

export const getLocale = (event: H3Event): string => {
    const query = getQuery(event);
    if (typeof query.locale === 'string') {
        return query.locale;
    }
    return getLocaleForUrl(getRequestURL(event)) ?? '_';
};

const configByLocale: Map<string, Config> = new Map();
export const loadConfig = async (locale: string): Promise<Config> => {
    return setDefault(configByLocale, locale, async () => {
        return loadSuml<Config>(`/locale/${locale}/config.suml`);
    });
};

const baseTranslations = await loadSuml('locale/_base/translations.suml');
const translatorByLocale: Map<string, Translator> = new Map();
export const loadTranslator = async (locale: string): Promise<Translator> => {
    return setDefault(translatorByLocale, locale, async () => {
        const [config, translations] =
            await Promise.all([loadConfig(locale), loadSuml(`locale/${locale}/translations.suml`)]);
        return new Translator(translations, baseTranslations, config);
    });
};

const pronounsByLocale: Map<string, Record<string, Pronoun>> = new Map();
export const loadPronouns = async (locale: string): Promise<Record<string, Pronoun>> => {
    return setDefault(pronounsByLocale, locale, async () => {
        const [config, pronounsRaw] = await Promise.all([
            loadConfig(locale),
            loadTsv<PronounData<string>>(`locale/${locale}/pronouns/pronouns.tsv`),
        ]);
        return parsePronouns(config, pronounsRaw);
    });
};

const pronounGroupsByLocale: Map<string, PronounGroup[]> = new Map();
export const loadPronounGroups = async (locale: string): Promise<PronounGroup[]> => {
    return setDefault(pronounGroupsByLocale, locale, async () => {
        return parsePronounGroups(await loadTsv(`locale/${locale}/pronouns/pronounGroups.tsv`));
    });
};

const pronounLibraryByLocale: Map<string, PronounLibrary> = new Map();
export const loadPronounLibrary = async (locale: string): Promise<PronounLibrary> => {
    return setDefault(pronounLibraryByLocale, locale, async () => {
        const [config, pronounGroups, pronouns] =
            await Promise.all([loadConfig(locale), loadPronounGroups(locale), loadPronouns(locale)]);
        return new PronounLibrary(config, pronounGroups, pronouns);
    });
};

const pronounExamplesByLocale: Map<string, PronounExamplesData[]> = new Map();
export const loadPronounExamples = async (locale: string): Promise<PronounExamplesData[]> => {
    return setDefault(pronounExamplesByLocale, locale, async () => {
        return loadTsv<PronounExamplesData>(`locale/${locale}/pronouns/examples.tsv`);
    });
};

const nounsDataByLocale: Map<string, NounsData> = new Map();
export const loadNounsData = async (locale: string): Promise<NounsData> => {
    return setDefault(nounsDataByLocale, locale, async () => {
        return loadSuml<NounsData>(`locale/${locale}/nouns/nounsData.suml`);
    });
};

const calendarByLocale: Map<string, Calendar> = new Map();
export const loadCalendar = async (locale: string): Promise<Calendar> => {
    return setDefault(calendarByLocale, locale, async () => {
        const localeEventImports = (await import('#virtual/calendar/events.ts')).default;
        const localEvents = await localeEventImports[locale]();
        return buildCalendar(localEvents, getUrlForLocale(locale));
    });
};