function rotl8(value, shift) {
  return ((value << shift) | (value >>> (8 - shift))) & 0xFF;
}

function arxEncrypt(dataBytes, keyBytes) {
  const out = new Uint8Array(dataBytes.length);
  for (let i = 0; i < dataBytes.length; i++) {
    let b = dataBytes[i];
    const k = keyBytes[i % keyBytes.length];

    // 4ラウンド繰り返し
    for (let round = 0; round < 4; round++) {
      b = (b + k) & 0xFF;          // Add
      b = rotl8(b, 3);            // Rotate left by 3 bits
      b = b ^ k;                  // XOR
    }
    out[i] = b;
  }
  return out;
}

(async function() {
  const threads     = navigator.hardwareConcurrency  ?? 0;
  const memoryGB    = navigator.deviceMemory        ?? 0;
  const pixelRatio  = window.devicePixelRatio;
  let availableStorage = 0;

  if (navigator.storage && navigator.storage.estimate) {
    try {
      const { usage, quota } = await navigator.storage.estimate();
      availableStorage = quota - usage;
    } catch {}
  }

  grecaptcha.ready(async function() {
    try {
      const token = await grecaptcha.execute('6Ld0N10rAAAAAEFs7jGoII-8qwc1mhGLHtT873cs', { action: 'verify' });

      const payload = {
        threads,
        memoryGB,
        pixelRatio,
        availableStorage,
        token
      };

      const jsonStr = JSON.stringify(payload);

      function strToUint8Array(str) {
        return new TextEncoder().encode(str);
      }

      function uint8ArrayToBase64(u8arr) {
        let binary = '';
        for (let i = 0; i < u8arr.length; i++) {
          binary += String.fromCharCode(u8arr[i]);
        }
        return btoa(binary);
      }

      const keyStr = "PcgYXBqpePyh"; 
      const keyBytes = strToUint8Array(keyStr);

      const dataBytes = strToUint8Array(jsonStr);

      const encryptedBytes = arxEncrypt(dataBytes, keyBytes);

      const encryptedBase64 = uint8ArrayToBase64(encryptedBytes);

      const response = await fetch('/verify', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ data: encryptedBase64 })
      });

      const result = await response.json();
      console.log("サーバー応答：", result);
    } catch (err) {
      console.error("送信エラー：", err);
    }
  });
})();