/**
 * Languages Loader
 */

const fs = require("fs");
const yaml = require("yaml");

const languages = [];
const languages_custom = [];

const merge = (...args) =>
	args.reduce(
		(a, c) => ({
			...a,
			...c,
			...Object.entries(a)
				.filter(([k]) => c && typeof c[k] === "object")
				.reduce((a, [k, v]) => ((a[k] = merge(v, c[k])), a), {}),
		}),
		{}
	);

fs.readdirSync(__dirname).forEach((file) => {
	if (file.includes(".yml")) {
		locale = file.slice(0, file.indexOf("."));
		languages.push(locale);
	}
});

fs.readdirSync(`${__dirname}/../custom/locales`).forEach((file) => {
	if (file.includes(".yml")) {
		customLocale = file.slice(0, file.indexOf("."));
		languages_custom.push(customLocale);
	}
});

const primaries = {
	en: "US",
	ja: "JP",
	zh: "CN",
};

const locales = languages.reduce(
	(a, c) =>
		(a[c] = yaml.parse(fs.readFileSync(`${__dirname}/${c}.yml`, "utf-8"))) ||
		{},
	a
);
const locales_custom = languages_custom.reduce(
	(a, c) =>
		(a[c] = yaml.parse(
			fs.readFileSync(`${__dirname}/../custom/locales/${c}.yml`, "utf-8")
		)) || {},
	a
);
Object.assign(locales, locales_custom);

module.exports = Object.entries(locales).reduce(
	(a, [k, v]) => (
		(a[k] = (() => {
			const [lang] = k.split("-");
			switch (k) {
				case "ja-JP":
					return v;
				case "ja-KS":
				case "en-US":
					return merge(locales["ja-JP"], v);
				default:
					return merge(
						locales["ja-JP"],
						locales["en-US"],
						locales[`${lang}-${primaries[lang]}`] || {},
						v
					);
			}
		})()),
		a
	),
	{}
);