import { execFile } from 'child_process';
import { mkdtemp, readFile, rm } from 'fs/promises';
import { tmpdir } from 'os';
import { basename, join } from 'path';
import { promisify } from 'util';

const execFileAsync = promisify(execFile);

export default async function createVideoPoster(videoPath: string): Promise<string|null> {
	if (process.platform !== 'darwin') return null;

	const outputDirectory = await mkdtemp(join(tmpdir(), 'joplin-video-thumbnail-'));
	try {
		await execFileAsync('/usr/bin/qlmanage', ['-t', '-s', '920', '-o', outputDirectory, videoPath], {
			timeout: 15_000,
			maxBuffer: 1024 * 1024,
		});

		const thumbnail = await readFile(join(outputDirectory, `${basename(videoPath)}.png`));
		return `data:image/png;base64,${thumbnail.toString('base64')}`;
	} catch {
		return null;
	} finally {
		await rm(outputDirectory, { force: true, recursive: true });
	}
}