/**
 * Config loader
 */

import * as fs from "node:fs";
import {fileURLToPath} from "node:url";
import {dirname} from "node:path";
import * as yaml from "js-yaml";
import type {Mixin, Source} from "./types.js";

const _filename = fileURLToPath(import.meta.url);
const _dirname = dirname(_filename);

/**
 * Path of configuration directory
 */
const dir = `${_dirname}/../../../../.config`;

/**
 * Path of configuration file
 */
const path =
	process.env.NODE_ENV === "test" ? `${dir}/test.yml` : `${dir}/default.yml`;

export default function load() {
	const meta = JSON.parse(
		fs.readFileSync(`${_dirname}/../../../../package.json`, "utf-8"),
	);

	const config = yaml.load(fs.readFileSync(path, "utf-8")) as Source;

	const mixin = {} as Mixin;

	const url = tryCreateUrl(config.url);

	config.url = url.origin;

	config.port = config.port || parseInt(process.env.PORT || "", 10);

	mixin.version = meta.version;
	mixin.host = url.host;
	mixin.hostname = url.hostname;
	mixin.scheme = url.protocol.replace(/:$/, "");
	mixin.wsScheme = mixin.scheme.replace("http", "ws");
	mixin.wsUrl = `${mixin.wsScheme}://${mixin.host}`;
	mixin.apiUrl = `${mixin.scheme}://${mixin.host}/api`;
	mixin.authUrl = `${mixin.scheme}://${mixin.host}/auth`;
	mixin.driveUrl = `${mixin.scheme}://${mixin.host}/files`;
	mixin.userAgent = `Calckey/${meta.version} (${config.url})`;

	if (!config.redis.prefix) config.redis.prefix = mixin.host;

	return Object.assign(config, mixin);
}

function tryCreateUrl(url: string) {
	try {
		return new URL(url);
	} catch (e) {
		throw new Error(`url="${url}" is not a valid URL.`);
	}
}