// For documentation on i18n in Zulip, see:
// https://zulip.readthedocs.io/en/latest/translating/internationalization.html

import type {MessageDescriptor} from "@formatjs/intl";
import {DEFAULT_INTL_CONFIG, IntlErrorCode, createIntl, createIntlCache} from "@formatjs/intl";
import type {FormatXMLElementFn, PrimitiveType} from "intl-messageformat";
import _ from "lodash";

import {page_params} from "./page_params";

const cache = createIntlCache();
export const intl = createIntl(
    {
        locale: page_params.request_language,
        defaultLocale: "en",
        messages: page_params.translation_data,
        /* istanbul ignore next */
        onError(error) {
            // Ignore complaints about untranslated strings that were
            // added since the last sync-translations run.
            if (error.code !== IntlErrorCode.MISSING_TRANSLATION) {
                DEFAULT_INTL_CONFIG.onError(error);
            }
        },
    },
    cache,
);

export const $t = intl.formatMessage.bind(intl);

export const default_html_elements = Object.fromEntries(
    ["b", "code", "em", "i", "kbd", "p", "strong"].map((tag) => [
        tag,
        (content_html: string[]) => `<${tag}>${content_html.join("")}</${tag}>`,
    ]),
);

export function $t_html(
    descriptor: MessageDescriptor,
    values?: Record<string, PrimitiveType | FormatXMLElementFn<string, string>>,
): string {
    return intl.formatMessage(descriptor, {
        ...default_html_elements,
        ...Object.fromEntries(
            Object.entries(values ?? {}).map(([key, value]) => [
                key,
                typeof value === "function" ? value : _.escape(value?.toString()),
            ]),
        ),
    });
}

export let language_list: typeof page_params["language_list"];

export function get_language_name(language_code: string): string {
    const language_list_map: Record<string, string> = {};

    // One-to-one mapping from code to name for all languages
    for (const language of language_list) {
        language_list_map[language.code] = language.name;
    }
    return language_list_map[language_code];
}

export function initialize(language_params: {language_list: typeof language_list}): void {
    const language_list_raw = language_params.language_list;

    // Limit offered languages to options with percentage translation >= 5%
    language_list = [];
    for (const language of language_list_raw) {
        if (language.percent_translated === undefined || language.percent_translated >= 5) {
            language_list.push({
                code: language.code,
                locale: language.locale,
                name: language.name,
                percent_translated: language.percent_translated,
            });
        }
    }
}

type Language = {
    code: string;
    name: string;
    name_with_percent: string;
    selected: boolean;
};

export function get_language_list_columns(default_language: string): Language[] {
    const formatted_list: Language[] = [];
    for (const language of language_list) {
        let name_with_percent = language.name;
        if (language.percent_translated !== undefined) {
            name_with_percent = `${language.name} (${language.percent_translated}%)`;
        }

        const selected = default_language === language.code || default_language === language.locale;
        formatted_list.push({
            code: language.code,
            name: language.name,
            name_with_percent,
            selected,
        });
    }
    return formatted_list;
}