/* eslint-disable import/prefer-default-export */

import { mkdirp } from 'fs-extra';
import { mkdtemp, utimes } from 'fs/promises';
import { FileLocker } from './fs';
import { msleep, Second } from './time';

const baseTempDir = `${__dirname}/../app-cli/tests/tmp`;

export const createTempDir = async () => {
	await mkdirp(baseTempDir);
	return mkdtemp(`${baseTempDir}/`);
};

describe('fs', () => {

	it('should lock files', async () => {
		const dirPath = await createTempDir();
		const filePath = `${dirPath}/test.lock`;

		const locker1 = new FileLocker(filePath, {
			interval: 10 * Second,
		});

		expect(await locker1.lock()).toBe(true);
		expect(await locker1.lock()).toBe(false);

		locker1.unlockSync();

		const locker2 = new FileLocker(filePath, {
			interval: 1.5 * Second,
		});

		expect(await locker2.lock()).toBe(true);
		locker2.stopMonitoring_();

		const locker3 = new FileLocker(filePath, {
			interval: 1.5 * Second,
		});

		await msleep(2 * Second);

		expect(await locker3.lock()).toBe(true);

		locker3.unlockSync();
	});

	it('should not unlock a file owned by another locker', async () => {
		const dirPath = await createTempDir();
		const filePath = `${dirPath}/test.lock`;
		const options = { interval: 10 * Second };

		const locker1 = new FileLocker(filePath, options);
		const locker2 = new FileLocker(filePath, options);
		const locker3 = new FileLocker(filePath, options);

		expect(await locker1.lock()).toBe(true);
		expect(await locker2.lock()).toBe(false);

		locker2.unlockSync();

		expect(await locker3.lock()).toBe(false);

		locker1.unlockSync();

		expect(await locker3.lock()).toBe(true);
		locker3.unlockSync();
	});

	it('should not unlock a file taken over by another locker', async () => {
		const dirPath = await createTempDir();
		const filePath = `${dirPath}/test.lock`;
		const options = { interval: 10 * Second };

		const locker1 = new FileLocker(filePath, options);
		const locker2 = new FileLocker(filePath, options);
		const locker3 = new FileLocker(filePath, options);

		try {
			expect(await locker1.lock()).toBe(true);
			// Simulate a delayed heartbeat without clearing the old owner's timer.
			const staleTime = new Date(Date.now() - 2 * options.interval);
			await utimes(filePath, staleTime, staleTime);

			expect(await locker2.lock()).toBe(true);
			locker1.unlockSync();
			expect(await locker3.lock()).toBe(false);

			locker2.unlockSync();
			expect(await locker3.lock()).toBe(true);
			// Repeated cleanup must also preserve a subsequent owner's lock.
			locker2.unlockSync();
			expect(await locker1.lock()).toBe(false);
		} finally {
			locker1.unlockSync();
			locker2.unlockSync();
			locker3.unlockSync();
		}
	});

});