index.js

#!/usr/bin/env node
const packageJson = require("./package.json");
const commander = require("commander");
const mustache = require("mustache");
const fs = require("fs-extra");
const crypto = require("crypto");
const path = require("path");
const JSZip = require("jszip");

commander
  .version(packageJson.version)
  .option(
    "-m, --memory [bytes]",
    "how much memory your game will require [16777216]",
    16777216,
  )
  .option("-c, --compatibility", "specify flag to use compatibility version")
  .arguments("<input> <output>")
  .action((input, output) => {
    commander.input = input;
    commander.output = output;
  });
commander._name = "love.js";
commander.parse(process.argv);

const getMD5 = (pathname) =>
  new Promise((resolve, reject) => {
    const hash = crypto.createHash("md5");
    const rs = fs.createReadStream(pathname);
    rs.on("error", reject);
    rs.on("data", (chunk) => hash.update(chunk));
    rs.on("end", () => resolve(hash.digest("hex")));
  });

// prompt for args left out of the cli invocation
const getAdditionalInfo = async function getAdditionalInfo(parsedArgs) {
  const prompt = function prompt(msg) {
    return new Promise((done) => {
      process.stdout.write(msg);
      process.stdin.setEncoding("utf8");
      process.stdin.once("data", (val) => {
        process.stdin.unref();
        done(val.trim());
      });
    });
  };

  const args = {
    title: "A game made with LÖVE",
    memory: parsedArgs.memory,
    input: parsedArgs.input,
    output: parsedArgs.output,
    compat: parsedArgs.compatibility,
    window: {
      width: 800,
      height: 600,
    },
    game_data_filename: "game.data",
  };
  args.input = parsedArgs.input || (await prompt("Love file or directory: "));
  args.output = parsedArgs.output || (await prompt("Output directory: "));

  if (fs.statSync(args.input).isDirectory() || !args.input.endsWith(".love")) {
    throw new Error("Input must be a .love game file");
  }

  return args;
};

const getFiles = async function getFiles(args) {
  const loveGame = fs.readFileSync(args.input);
  const zip = await JSZip.loadAsync(loveGame);
  const loveConf = await zip.file("conf.lua").async("string");
  const title = loveConf.match(/t\.window\.title\s*=\s*(.*)\s*/);
  const width = loveConf.match(/t\.window\.width\s*=\s*([0-9]+)\s*/);
  const height = loveConf.match(/t\.window\.height\s*=\s*([0-9]+)\s*/);
  if (title) args.title = title[1].substring(1, title[1].length - 1);
  if (width) args.window.width = parseInt(width[1], 10);
  if (height) args.window.height = parseInt(height[1], 10);
  args.game_data_filename = path.basename(args.input).replace(".love", ".data");
  args.etag = await getMD5(args.input);

  return [args, { path: path.resolve(args.input) }];
};

getAdditionalInfo(commander)
  .then((args) => {
    const outputDir = path.resolve(args.output);
    const srcDir = path.resolve(__dirname, "src");

    getFiles(args).then(([args, file]) => {
      const buffer = fs.readFileSync(file.path);

      args.game_size = buffer.length;

      if (args.memory < buffer.length) {
        throw new Error(
          "The memory (-m, --memory [bytes]) allocated for your game should at least be as big as your assets. " +
            `The total size of your assets is ${buffer.length} bytes.`,
        );
      }

      fs.mkdirsSync(`${outputDir}`);

      const fldrName = args.compat ? "compat" : "release";
      const template = fs.readFileSync(`${srcDir}/index.html`, "utf8");
      const renderedTemplate = mustache.render(template, args);

      fs.mkdirsSync(outputDir);
      fs.writeFileSync(`${outputDir}/index.html`, renderedTemplate);
      fs.writeFileSync(`${outputDir}/${args.game_data_filename}`, buffer);
      fs.copySync(`${srcDir}/love-game.js`, `${outputDir}/love-game.js`);
      fs.copySync(`${srcDir}/love-game.css`, `${outputDir}/love-game.css`);
      fs.copySync(`${srcDir}/game.js`, `${outputDir}/game.js`);
      fs.copySync(`${srcDir}/${fldrName}/love.js`, `${outputDir}/love.js`);
      fs.copySync(`${srcDir}/${fldrName}/love.wasm`, `${outputDir}/love.wasm`);

      if (fldrName === "release") {
        fs.copySync(
          `${srcDir}/${fldrName}/love.worker.js`,
          `${outputDir}/love.worker.js`,
        );
      }
    });
  })
  .catch((e) => {
    console.error(e.message);
    process.exit(1);
  });