const https = require('https');
const { ethers } = require('ethers');
const { encode } = require('@msgpack/msgpack');

const host = "api.hyperliquid-testnet.xyz";
const privKey = "0xcb4e58b6c0921fd4aa8e49cd8a9f06b98b4e6b9cdf7c60c63ba1416856bb0b2a";
const wallet = new ethers.Wallet(privKey);

async function api(method, path, payload) {
  return new Promise((resolve, reject) => {
    const data = JSON.stringify(payload);
    const opts = { hostname: host, path, method, headers: { 'Content-Type': 'application/json' } };
    const req = https.request(opts, res => {
      let body = '';
      res.on('data', c => body += c);
      res.on('end', () => { try { resolve(JSON.parse(body)); } catch(e) { resolve(body); } });
    });
    req.on('error', reject);
    req.write(data); req.end();
  });
}

async function sign(action) {
  const nonce = Date.now() * 1000000 + Math.floor(Math.random() * 1000000);
  
  // Normalize
  function normalize(obj) {
    if (!obj || typeof obj !== 'object') return;
    if (Array.isArray(obj)) { for (const i of obj) normalize(i); }
    else { for (const k of Object.keys(obj)) {
      if ((k === 'p' || k === 's') && typeof obj[k] === 'string')
        obj[k] = obj[k].replace(/\.?0+$/, '').replace(/^-0$/, '0');
      else normalize(obj[k]);
    }}
  }
  const act = JSON.parse(JSON.stringify(action));
  normalize(act);
  
  const msgBytes = encode(act);
  const buf = new Uint8Array(msgBytes.length + 8 + 1);
  buf.set(msgBytes, 0);
  new DataView(buf.buffer).setBigUint64(msgBytes.length, BigInt(nonce), false);
  buf[msgBytes.length + 8] = 0;
  const hash = ethers.keccak256(buf);
  
  const sig = ethers.Signature.from(await wallet.signTypedData(
    { name: 'Exchange', version: '1', chainId: 1337, verifyingContract: '0x0000000000000000000000000000000000000000' },
    { Agent: [{ name: 'source', type: 'string' }, { name: 'connectionId', type: 'bytes32' }] },
    { source: 'b', connectionId: hash }
  ));
  
  return { action, nonce, signature: { r: sig.r, s: sig.s, v: sig.v } };
}

async function main() {
  // Get meta to find asset index
  const meta = await api('POST', '/info', { type: 'meta' });
  const btcIdx = meta.universe.findIndex(u => u.name === 'BTC');
  console.log(`BTC asset index: ${btcIdx}`);
  
  // Get mid price for BTC
  const mids = await api('POST', '/info', { type: 'allMids' });
  const btcMid = parseFloat(mids['BTC']);
  console.log(`BTC mid: ${btcMid}`);
  
  // Place a small market buy order (IOC, high limit price)
  const orderAction = {
    type: 'order',
    orders: [{
      a: btcIdx,
      b: true,      // buy
      p: (btcMid * 2).toFixed(0),
      s: '0.001',
      r: false,
      t: { limit: { tif: 'Ioc' } }
    }],
    grouping: 'na'
  };
  
  const signed = await sign(orderAction);
  console.log('\nSending order...');
  const result = await api('POST', '/exchange', signed);
  console.log(JSON.stringify(result, null, 2));
}

main().catch(console.error);