import { Command } from 'commander';
import puppeteer from 'puppeteer';
import fs from 'fs';

const program = new Command();
program
	.requiredOption('-o, --output <output>', 'Output directory')
	.requiredOption('--fps <fps>', 'Frames per second')
	.requiredOption('--cycles <cycles>', 'Number of cycles')
	.requiredOption('--size <size>', 'Size of the output in pixels')
	.requiredOption('--url <url>', 'URL to render')
	.parse(process.argv);
const options = program.opts();

// mkdir p output path
if (!fs.existsSync(options.output)) {
	fs.mkdirSync(options.output, { recursive: true });
}

const browser = await puppeteer.launch({
	args: ['--no-sandbox']
});
const page = await browser.newPage();

await page.setViewport({ width: parseInt(options.size, 10), height: parseInt(options.size, 10) });
await page.goto(options.url);

await page.evaluate(async (fps) => {
	// @ts-ignore
	await window.setFps(fps);
}, options.fps);

const totalFrames = parseInt(options.fps) * parseInt(options.cycles);
for (let frame = 0; frame < totalFrames; frame++) {
	let start = Date.now();
	await page.evaluate(async (n) => {
		// @ts-ignore
		await window.setFrame(n);
	}, frame);
	const path = `${options.output}/${frame.toString().padStart(Math.log10(totalFrames) + 1, '0')}.png`;
	await page.screenshot({ path, omitBackground: true });
	let end = Date.now();
	console.log(`Captured frame ${frame + 1}/${totalFrames} (took ${end - start}ms)`);
}

console.log('Done.');

await browser.close();