function generatePeerId() {
  const bytes = new Uint8Array(8);
  crypto.getRandomValues(bytes);
  return Array.from(bytes).map(b => b.toString(16).padStart(2, '0')).join('');
}

async function generateSecret() {
  const secret = new Uint8Array(32);
  crypto.getRandomValues(secret);
  return secret;
}

async function commit(secret) {
  const hash = await crypto.subtle.digest('SHA-256', secret);
  return new Uint8Array(hash);
}

function arraysEqual(a, b) {
  if (a.length !== b.length) return false;
  let diff = 0;
  for (let i = 0; i < a.length; i++) {
    diff |= a[i] ^ b[i];
  }
  return diff === 0;
}

function combine(secrets) {
  const result = new Uint8Array(32);
  for (const secret of secrets) {
    for (let i = 0; i < 32; i++) {
      result[i] ^= secret[i];
    }
  }
  return result[0] & 1;
}

function bufToBase64(buf) {
  const bytes = new Uint8Array(buf);
  let binary = '';
  for (let i = 0; i < bytes.length; i++) {
    binary += String.fromCharCode(bytes[i]);
  }
  return btoa(binary);
}

function base64ToBuf(base64) {
  const binary = atob(base64);
  const bytes = new Uint8Array(binary.length);
  for (let i = 0; i < binary.length; i++) {
    bytes[i] = binary.charCodeAt(i);
  }
  return bytes;
}

function hexToBuf(hex) {
  const bytes = new Uint8Array(hex.length / 2);
  for (let i = 0; i < hex.length; i += 2) {
    bytes[i / 2] = parseInt(hex.substring(i, i + 2), 16);
  }
  return bytes;
}