packwiz-generator.js

packwiz-generator.js

// packwiz-generator - make a multimc instance zip for packwiz
// node index.js <URL to pack.toml>
// (c) notnite 2023, MIT license

const fs = require("fs");
const AdmZip = require("adm-zip");
const TOML = require("@iarna/toml");

const packUrl = process.argv[2];

const boostrapUrl =
  "https://github.com/packwiz/packwiz-installer-bootstrap/releases/latest/download/packwiz-installer-bootstrap.jar";
const bootstrapOut = "./tmp/.minecraft/packwiz-installer-bootstrap.jar";
const instanceCfgOut = "./tmp/instance.cfg";
const mmcPackOut = "./tmp/mmc-pack.json";

async function main() {
  console.log("making directories...");
  if (!fs.existsSync("./out/")) fs.mkdirSync("./out/");

  if (fs.existsSync("./tmp")) fs.rmSync("./tmp", { recursive: true });
  fs.mkdirSync("./tmp");
  fs.mkdirSync("./tmp/.minecraft");

  console.log("downloading bootstrap...");
  const bootstrap = await fetch(boostrapUrl).then((res) => res.arrayBuffer());
  fs.writeFileSync(bootstrapOut, Buffer.from(bootstrap));

  console.log("fetching pack...");
  const pack = await fetch(packUrl)
    .then((res) => res.text())
    .then(TOML.parse);
  const packName = pack.name;

  console.log("writing instance.cfg...");
  const instanceCfg = `
[General]
name=${packName}
OverrideCommands=true
PreLaunchCommand=$INST_JAVA -jar packwiz-installer-bootstrap.jar ${packUrl}
`.trim();
  fs.writeFileSync(instanceCfg, instanceCfg);

  // https://github.com/packwiz/packwiz-installer/blob/7b6daaf7e552f44888d68dcd8235822dd1c2956e/src/main/kotlin/link/infra/packwiz/installer/LauncherUtils.kt#LL48C2-L48C2
  const nameMappings = {
    minecraft: "net.minecraft",
    forge: "net.minecraftforge",
    fabric: "net.fabricmc.fabric-loader",
    quilt: "org.quiltmc.quilt-loader",
    liteloader: "com.mumfrey.liteloader"
  };

  const components = Object.entries(pack.versions).map(([name, version]) => ({
    uid: nameMappings[name],
    version: version
  }));

  const mmcPack = {
    formatVersion: 1,
    components
  };

  console.log("writing mmc-pack.json...");
  fs.writeFileSync(mmcPackOut, JSON.stringify(mmcPack));

  console.log("compressing...");
  const zip = new AdmZip();
  zip.addLocalFolder("./tmp");
  zip.writeZip(`./out/${packName}.zip`);
}

main();