Provably Fair

// Verify a Lock Slot spin result
const crypto = require('crypto');

function verifySpin(serverSeed, clientSeed, nonce) {
  // Step 1: Generate combined hash
  const combined = `${serverSeed}:${clientSeed}:${nonce}`;
  const hash = crypto.createHash('sha256').update(combined).digest('hex');
  
  // Step 2: Convert first 8 hex chars to roll value (0-1)
  const rollValue = parseInt(hash.substring(0, 8), 16) / 0x100000000;
  
  // Step 3: Determine tier from roll value
  const tiers = [
    { name: 'brick', threshold: 0.45 },
    { name: 'mid', threshold: 0.73 },
    { name: 'hot', threshold: 0.88 },
    { name: 'legendary', threshold: 0.97 },
    { name: 'mythic', threshold: 1.00 }
  ];
  
  let tier = 'brick';
  for (const t of tiers) {
    if (rollValue < t.threshold) {
      tier = t.name;
      break;
    }
  }
  
  return { hash, rollValue, tier };
}

// Verify server seed commitment
function verifyServerSeed(revealedSeed, publishedHash) {
  const calculatedHash = crypto.createHash('sha256')
    .update(revealedSeed)
    .digest('hex');
  return calculatedHash === publishedHash;
}

// Example usage:
const result = verifySpin(
  'your_server_seed_here',
  'your_client_seed_here',
  1  // your spin nonce
);
console.log(result);