import { sha256 } from "@noble/hashes/sha256";
import { bytesToHex, hexToBytes } from "@noble/hashes/utils";

const TERMINATING_HASH = "567a98370fb7545137ddb53687723cf0b8a1f5e93b1f76f4a1da29416930fa59";

function verifyInChain(hash: Uint8Array) {
  for (let gameId = 1; gameId < 100e6; gameId++) {
    hash = sha256(hash);
    if (bytesToHex(hash) === TERMINATING_HASH) {
      console.log("hash is in the chain. It is game: ", gameId);
      return gameId;
    }
  }
  console.error("hash is not in the chain");
}

verifyInChain(
  hexToBytes("70eed5c29bde5132f4e41ec8b117a31533e5b055c6c21174d932b377a1855a04")
);

import { bls12_381 as bls } from "@noble/curves/bls12-381";
import { concatBytes, utf8ToBytes } from "@noble/hashes/utils";

const VX_PUBKEY = "b40c94495f6e6e73619aeb54ec2fc84c5333f7a88ace82923946fc5b6c8635b08f9130888dd96e1749a1d5aab00020e4";

function validateSignature(
  gameSalt: string, // the hash of block 831500
  prevGameHash: Uint8Array,
  vxSignature: Uint8Array
) {
  const message = concatBytes(prevGameHash, utf8ToBytes(gameSalt));
  return bls.verify(vxSignature, message, VX_PUBKEY);
}

import { hmac } from "@noble/hashes/hmac";
import { sha256 } from "@noble/hashes/sha256";
import { bytesToHex } from "@noble/hashes/utils";

export function gameResult(vxSignature: Uint8Array, gameHash: Uint8Array) {
  const nBits = 52; // number of most significant bits to use

  // 1. HMAC_SHA256(key=signature, message=hash)
  const hash = bytesToHex(hmac(sha256, vxSignature, gameHash));

  // 2. r = 52 most significant bits
  const seed = hash.slice(0, nBits / 4);
  const r = Number.parseInt(seed, 16);

  // 3. X = r / 2^52
  let X = r / Math.pow(2, nBits); // uniformly distributed in [0; 1)

  // 4. X = 99 / (1 - X)
  X = 99 / (1 - X); // 1 - X so there's no chance of div-by-zero

  // 5. return max(trunc(X), 100)
  const result = Math.floor(X);
  return Math.max(1, result / 100);
}

maxVerifiedGame = { gameId: 23, hash: "0f08611e0751a8311ef15d80ed83fa78f7d44e8e0713e47da8481ebba240c665" }