const ranges = [
    { minRange: 1, maxRange: 12, tag: "Spin" }
];

function incrementNonce(nonce, offset) {
  let seconds = parseInt(nonce.slice(0, 2), 10);
  let minutes = parseInt(nonce.slice(2, 4), 10);
  let hours = parseInt(nonce.slice(4, 6), 10);
  let day = parseInt(nonce.slice(6, 8), 10);
  let month = parseInt(nonce.slice(8, 10), 10);
  let year = parseInt(nonce.slice(10, 14), 10);

  seconds += offset;
  while (seconds > 59) {
    seconds -= 60;
    minutes += 1;
    if (minutes > 59) {
      minutes = 0;
      hours += 1;
      if (hours > 23) {
        hours = 0;
        day += 1;
        const daysInMonth = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
        if (day > daysInMonth[month - 1]) {
          day = 1;
          month += 1;
          if (month > 12) {
            month = 1;
            year += 1;
          }
        }
      }
    }
  }

  return (
    seconds.toString().padStart(2, '0') +
    minutes.toString().padStart(2, '0') +
    hours.toString().padStart(2, '0') +
    day.toString().padStart(2, '0') +
    month.toString().padStart(2, '0') +
    year.toString().padStart(4, '0')
  );
}

async function generateHmacSha512(key, message) {
  const keyBuffer = new TextEncoder().encode(key);
  const msgBuffer = new TextEncoder().encode(message);
  const cryptoKey = await crypto.subtle.importKey(
    "raw",
    keyBuffer,
    { name: "HMAC", hash: "SHA-512" },
    false,
    ["sign"]
  );
  const signature = await crypto.subtle.sign("HMAC", cryptoKey, msgBuffer);
  return new Uint8Array(signature);
}

async function generateRandomNumbers(ranges, serverSeed, clientSeed, nonce) {
  const randomNumbers = [];
  const numbersPerDigest = 16;
  const digestsNeeded = Math.ceil(ranges.length / numbersPerDigest);

  for (let digestIndex = 0; digestIndex < digestsNeeded; digestIndex++) {
    const message = `${clientSeed}:${nonce}:${digestIndex}`;
    const digest = await generateHmacSha512(serverSeed, message);
    let offset = 0;

    for (let i = 0; i < numbersPerDigest && randomNumbers.length < ranges.length; i++) {
      const range = ranges[randomNumbers.length];
      const bytes = digest.slice(offset, offset + 4);
      const view = new DataView(bytes.buffer, bytes.byteOffset, 4);
      const num = view.getUint32(0, false); // Big-endian
      const rand = Math.floor((num / 0x100000000) * (range.maxRange - range.minRange + 1)) + range.minRange;
      randomNumbers.push(rand);
      offset += 4;
    }
  }

  return randomNumbers;
}

async function mapTaggedResults(randomNumbers, ranges, serverSeed, clientSeed, nonce) {
  const seenValues = {};
  const taggedResults = [];

  for (let index = 0; index < randomNumbers.length; index++) {
    if (!ranges[index]) {
      console.error(`No range found for index ${index}`);
      continue;
    }

    const { tag = "UNKNOWN", minRange, maxRange } = ranges[index];
    let finalNumber = randomNumbers[index];
    let nonceOffset = 0;

    if (!seenValues[tag]) {
      seenValues[tag] = new Set();
    }

    while (seenValues[tag].has(finalNumber.toString())) {
      nonceOffset++;
      const newNonce = incrementNonce(nonce, nonceOffset);
      const message = `${clientSeed}:${newNonce}`;
      const digest = await generateHmacSha512(serverSeed, message);
      const bytes = digest.slice(0, 4);
      const view = new DataView(bytes.buffer, bytes.byteOffset, 4);
      const newNum = view.getUint32(0, false); // Big-endian
      finalNumber = Math.floor((newNum / 0x100000000) * (maxRange - minRange + 1)) + minRange;
    }

    seenValues[tag].add(finalNumber.toString());
    taggedResults.push({ value: finalNumber.toString(), tag });
  }

  return taggedResults;
}

async function filterResults(taggedResults) {
  return taggedResults.filter(item => item.tag === "Spin").slice(0, 1);
}

async function setData(serverSeed, clientSeed, nonce) {
  const randomNumbers = await generateRandomNumbers(ranges, serverSeed, clientSeed, nonce);
  const taggedResults = await mapTaggedResults(randomNumbers, ranges, serverSeed, clientSeed, nonce);
  const filteredResults = await filterResults(taggedResults);

  return {
    success: true,
    result: filteredResults,
    nonce,
    serverSeed,
    clientSeed
  };
}
export { setData };