import { createLogger } from '@gongt/ts-stl-library/debug/create-logger';
import { LOG_LEVEL } from '@gongt/ts-stl-library/debug/levels';
import { createWaiter, IWaitter } from './wait';

const debug = createLogger(LOG_LEVEL.DEBUG, 'wait-app');
const sill = createLogger(LOG_LEVEL.SILLY, 'wait-app');

let appReady = false;
let wait: IWaitter;
const p: Promise<void> = new Promise((resolve, reject) => {
	wait = createWaiter(function (err) {
		appReady = true;
		return err? reject(err) : resolve();
	});
});

export function isAppReady() {
	return appReady;
}

export function waitAppStart(): Promise<void> {
	sill('someone waiting app start.');
	return p;
}

export function backgroundJob(runner: () => Promise<any>) {
	waitAppStart().then(runner).catch((e) => {
		setImmediate(() => {
			throw e;
		});
	});
}

setTimeout(() => {
	wait('empty listen', new Promise((resolve) => {
		setImmediate(resolve);
	}));
}, 0);

export function pushInitList(title: string, p: PromiseLike<any>) {
	if (appReady) {
		throw new Error(`try to init "${title}", but app already started.`);
	}
	debug('new job: %s', title);
	wait(title, p);
}