const assert = require('node:assert');
const { spawn } = require('node:child_process');
const fs = require('node:fs');

const { Browser, Builder, By } = require('selenium-webdriver');
const firefox = require('selenium-webdriver/firefox');

async function test() {
 	const generate_env_var = process.env.OSM_MAP_GENERATE_DATA || 'false';
	const generete_data = generate_env_var === '1' || generate_env_var.toLowerCase() === 'true';

	const server = spawn('node', ['scripts/server.js'], {stdio: [null, null, 'inherit']}); // show stderr (stdout is read)
	console.log('Creating selenium driver');
	const options = new firefox.Options();
	options.addArguments('--headless');
	const driver = await new Builder().forBrowser(Browser.FIREFOX).setFirefoxOptions(options).build();
	try
	{
		const max_try = 5;
		let read_try = 0;
		for(; read_try < max_try; read_try +=1)
		{
			const server_out = server.stdout.read();
			if(server_out != null)
			{
				assert.equal('Server is listening on port 8080\n', server_out.toString(), 'Server not starting properly');
				break;
			}
			await driver.sleep(50);
		}
		assert.notEqual(read_try, max_try, 'Timeout waiting for server starting');

		const test_name = 'test';
		console.log('Fetching test html');
		await driver.get('http://localhost:8080/build/packages/osm-map-nano/dist/test.html');
		assert.equal(`OSM Map Test : ${test_name}`, await driver.getTitle(), 'Wrong HTML title');

		let canvas = await driver.findElement(By.id('canvas-test'));
		const image_url_prefix = 'data:image/png;base64,';
		const image_data = Buffer.from(
			(await driver.executeScript('return arguments[0].toDataURL()', canvas)).substring(image_url_prefix.length), 'base64');
		const expected_data = fs.readFileSync('data/test.png');
		if(generete_data)
		{
			if(!expected_data.equals(image_data))
			{
				console.log(`Generating image for test ${test_name}`);
				fs.writeFileSync('data/test.png', image_data);
			}
		}
		else
			assert.ok(expected_data.equals(image_data));
	}
	catch (error)
	{
		console.error('TEST FAILED');
		console.error(error);
	}
	finally
	{
		console.log('Exiting selenium driver');
		await driver.quit();
		server.kill('SIGINT');
	}
}

test();