Launch on purps.lol

import fs from "node:fs";
import { Keypair, VersionedTransaction } from "@solana/web3.js";
import nacl from "tweetnacl";
import bs58 from "bs58";

const API = "https://purps.lol/api/v1";
const creator = Keypair.fromSecretKey(Uint8Array.from(JSON.parse(fs.readFileSync("creator.json", "utf8"))));
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

async function call(path, body) {
  const res = await fetch(API + path, body ? { method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify(body) } : undefined);
  const json = await res.json();
  if (!json.ok) throw new Error(`${path}: ${json.error}`);
  return json.data;
}

// 1. the terms, signed
const terms = {
  name: "My Coin",
  symbol: "MINE",
  quoteMint: "So11111111111111111111111111111111111111112",
  feePreset: "airdrop",
  devBuySol: 0.1,
  creatorWallet: creator.publicKey.toBase58(),
};
const { ts, message } = await call("/launches/prepare", terms);
const signature = bs58.encode(nacl.sign.detached(new TextEncoder().encode(message), creator.secretKey));

// 2. build
const build = await call("/launches/submit", {
  ...terms,
  ts,
  signature,
  imageUrl: "https://example.com/my-coin.png",
  description: "Fees go to holders.",
  twitter: "https://x.com/mycoin",
});
console.log("mint", build.mint);

// 3. sign and send, one at a time
const mintKey = Keypair.fromSecretKey(bs58.decode(build.mintSecret));
for (const [i, b64] of build.transactions.entries()) {
  const tx = VersionedTransaction.deserialize(Buffer.from(b64, "base64"));
  tx.sign(i === build.createIndex ? [creator, mintKey] : [creator]);
  let { signature: sig, confirmed } = await call("/transactions/send", { transaction: Buffer.from(tx.serialize()).toString("base64") });
  while (!confirmed) {
    await sleep(2000);
    const st = await call(`/transactions/${sig}`);
    if (st.failed) throw new Error(`transaction ${sig} failed on chain`);
    confirmed = st.confirmed;
  }
  console.log("landed", sig);
}

// 4. wait for live
for (;;) {
  const launch = await call(`/launches/${build.mint}`);
  if (launch.status === "live") break;
  if (launch.status === "failed") throw new Error("launch failed");
  await sleep(3000);
}
console.log("live at", build.url);