build.js

const fs = require('fs');
const htmlMinifier = require('html-minifier');
const DEBUG = process.argv[2] == '--debug';

function load(path) { return fs.readFileSync(path).toString(); }

const fileCounts = {};

async function embed(file) {
	for (let i = 0; i < file.length; ++i) {
		if (file.substr(i, 7) == 'embed(\'') {
			let filename = '';
			for (let ii = i + 7; ii < file.length; ++ii) {
				if (file.substr(ii, 3) == '\');') {
					break;
				}
				filename += file[ii];
			}
			if (!fileCounts[filename]) {
				fileCounts[filename] = 0; 
			}
			const index = ++fileCounts[filename];
			let embeded = await embed(load(filename).replaceAll('%INDEX%', index).replaceAll('%HEADER_HEIGHT%', 46));
			if (!DEBUG) {
				if (filename.endsWith('main.js')) {
					embeded = `(() => {${embeded}})();`;
					embeded = require('@babel/core').transformSync(embeded, { presets: ['@babel/preset-env'] }).code;
				} else if (filename.endsWith('main.css')) {
					embeded = await require('postcss')([require('autoprefixer')]).process(embeded).css;
				}
			}

			file = file.substr(0, i) + embeded + file.substr(i + 10 + filename.length);
		}
	}
	return file;
}

(async function () {
	if (!fs.existsSync('build')) { fs.mkdirSync('build'); }

	// Build Client
	let client = await embed(load('client/main.htm'));
	if (!DEBUG) {
		client = htmlMinifier.minify(client, { minifyCSS: true, minifyJS: true, removeComments: true, sortClassName: true, sortAttributes: true, collapseWhitespace: true });
	}
	fs.writeFileSync('build/client.htm', client);

	// Build Server
	fs.writeFileSync('build/server.js', await embed(load('server/main.js')));
})();