currently, when you put a numerical or ascii text in that textarea "inputMessage" it shows: " The encryption result is: 230476 640492 256678 472750 359950 221487 28998 " for the word: " The decryption result is: encrypt". I want this textarea to perform the decryption for that actual number chain it shows in "The encryption result" for both ascii and numeric modes in "messageMode". you need to integrate this ability to perform within the same decryption button "decrypt-btn", by lefting the same functionality it does now. also, check for possible "bigint syntax" errors. does it perform actual decryption within functionality? do it has this ability to understand the pattern in encryption result numbers? no, it cannot fully handle that encryption number chain to convert it through ascii. check that ascii to numerical and numerical to ascii, because the algorithm and range used is not enough to handle big numbers or chain of numbers. there's some idea, if we include some prefix for actual encrypted numbers chain for algorithm to understand that this is an actual encrypted message but not the numbers or some chain of some numbers.: <html>
  <head>
    <style>
      body {
        padding: 5px;
        font-family: monospace, sans-serif;
        background-color: #f8f9fa;
      }

      h2 {
        color: #4e73df;
      }

      p {
        line-height: 1.5;
        font-size: 1em;
        margin-bottom: 5px;
      }

      span {
        color: #3ca23c;
        font-weight: bold;
        padding: 5px;
        border: 1px solid #3ca23c;
        border-radius: 5px;
        background-color: #d4edda;
        margin-left: 5px;
      }

      span.bit-size {
        background-color: #f8f9fa;
        border-color: #f8f9fa;
        margin-left: 0;
        padding: 0;
      }

      button {
        color: white;
        background-color: #007bff;
        border-color: #007bff;
        padding: 0.375rem 0.75rem;
        font-size: 1rem;
        border-radius: 0.25rem;
        margin-left: 10px;
        cursor: pointer;
      }

      label {
        margin-left: 10px;
      }

      textarea {
        width: 100%;
      }
    </style>
  </head>
  <body>
    <h2>RSA Encryption Algorithm Visualization</h2>
    <p>
      In this first section, I will generate two distinct prime numbers P and Q.
    </p>
    <p>
      These will be used to derive the public and private keys.
    </p>
    <label for="p">P: </label>
    <input type="number" id="p" pattern="\d*" placeholder="Leave empty for random generation" />
    <span id="pBitSize" class="bit-size">...</span>
    <p>
      <label for="q">Q: </label>
      <input type="number" id="q" pattern="\d*" placeholder="Leave empty for random generation" />
      <span id="qBitSize" class="bit-size">...</span>
      <span id="warningMsg" style="color:red;"></span>
    </p>
    <label for="maxRange">Max Prime Size for P and Q (Larger numbers increase encryption strength but require more computation): </label>
    <p>
      <input type="number" id="maxRange" pattern="\d*" value="" />
      <span id="maxRangeWarningMsg" style="color:red;">!!!WARNING!!! Setting Max Prime Size too big may result in crashes! </span>
    </p>
    <button id="generate-primes-btn">Generate Input for P + Q</button>
    <button id="generate-primes-random-btn">Generate Random P + Q</button>

    <p>
      Next, I will multiply the two prime numbers. The result is: <span id="multiplyPrimes">1444033</span> (<span id="modulusBitSize" class="bit-size"></span>) This is our modulus value, n, which is part of the public and private keys.
    </p>

    <p>
      Then, I get a number e (the encryption exponent) that is ... The number e is: <span id="encryptionExponent">...</span> This is also part of the public key.
    </p>

    <p>
      Next, I need to get a number d (the decryption exponent) that is ... The number d is: <span id="decryptionExponent">...</span> This is the secret number and part of the private key.
    </p>

    <h2>Encryption/Decryption</h2>
    <p>
      Enter a message to encrypt:
      <select id="messageMode">
        <option value="numeric">Numeric</option>
        <option value="ascii">ASCII</option>
      </select>
    </p>
    <textarea id="inputMessage" rows="2" cols="50"></textarea>
    </p>
    <span id="enwarningMsg" style="color:red;"></span>
    <p>
      <button id="encrypt-btn">Encrypt</button>
      <button id="decrypt-btn">Decrypt</button>
    </p>
    <p>
      The encryption result is:
      <span id="encryptionResult">...</span>
    </p>
    <p>
      The decryption result is:
      <span id="decryptionResult">...</span>
    </p>

    <script>
      const maxRange = 5000;
      let n, e, d; // define global variables for encryption and decryption

      // Utility function to check if an input is numeric
      function isNumeric(n) {
        return !isNaN(parseFloat(n)) && isFinite(n);
      }

      const maxSize = 1000; // Max size
      const threshold = 5000; // Threshold value
      let maxRangeInput = document.getElementById("maxRange");
      let warningMsg = document.getElementById("maxRangeWarningMsg");

      // Set initial value
      maxRangeInput.value = maxSize;

      maxRangeInput.onchange = function () {
        let value = maxRangeInput.value;
        if (value > threshold) {
          let confirmation = confirm(
            `!!!WARNING!!! Setting Max Prime Size too large (above ${threshold}) may result in crashes! Do you wish to continue?`
          );

          if (!confirmation) {
            maxRangeInput.value = maxSize; // Reset back to maxSize if declined
            warningMsg.textContent =
              "Max Range reset to safe value: " + maxSize;
          }
        } else {
          warningMsg.textContent = "";
        }
      };

      // Utility function to find the closest prime number
      function isPrime(num) {
        for (let i = 2, max = Math.sqrt(num); i <= max; i++) {
          if (num % i === 0) return false;
        }
        return num > 1;
      }

      function modularExponentiation(base, exponent, modulus) {
        if (modulus === 1n) return 0n;
        let result = 1n;
        for (let i = exponent; i > 0n; i /= 2n) {
          if (i % 2n === 1n) result = (result * base) % modulus;
          base = (base * base) % modulus;
        }
        return result;
      }

      function gcd(a, b) {
        while (b !== 0) {
          let t = a;
          a = b;
          b = t % b;
        }
        return a;
      }

      function closestPrime(num) {
        do num--;
        while (!isPrime(num));
        return num;
      }

      function generatePrimeNumbers() {
        const warningMsg = document.getElementById("warningMsg");
        const pBitSizeElement = document.getElementById("pBitSize");
        const qBitSizeElement = document.getElementById("qBitSize");

        let p = document.getElementById("p").value;
        // Check if input is empty or zero
        if (!isNumeric(p) || p == "" || p == "0") {
          warningMsg.textContent =
            "Invalid input: P should be numeric, not zero and max 5 digits.";
          return;
        }
        p = closestPrime(parseInt(p));

        let q = document.getElementById("q").value;
        // Check if input is empty or zero
        if (!isNumeric(q) || q == "" || q == "0") {
          warningMsg.textContent =
            "Invalid input: Q should be numeric, not zero and max 5 digits.";
          return;
        }
        q = closestPrime(parseInt(q));

        if (!isPrime(p) || p > maxRange) {
          warningMsg.textContent = `${p} is not a valid prime number. Prime numbers within the range should not exceed ${maxRange}.`;
          return;
        }
        if (!isPrime(q) || q > maxRange) {
          warningMsg.textContent = `${q} is not a valid prime number. Prime numbers within the range should not exceed ${maxRange}.`;
          return;
        }

        n = p * q;
        document.getElementById("multiplyPrimes").textContent = n;
        const totient = (p - 1) * (q - 1);

        e = 2;
        while (gcd(e, totient) !== 1) {
          e++;
        }
        document.getElementById("encryptionExponent").textContent = e;

        d = 1;
        while ((e * d) % totient !== 1 || e === d) {
          d++;
        }
        document.getElementById("decryptionExponent").textContent = d;
        document.getElementById("p").value = p;
        document.getElementById("q").value = q;

        // Calculate bit size for P and Q
        const pBitSize = Math.ceil(Math.log2(p + 1));
        const qBitSize = Math.ceil(Math.log2(q + 1));

        pBitSizeElement.innerHTML = `${pBitSize} bits`;
        qBitSizeElement.innerHTML = `${qBitSize} bits`;

        const modulusBitSize = Math.ceil(Math.log2(n + 1));
        document.getElementById("modulusBitSize").innerHTML = `${modulusBitSize} bits`;

        warningMsg.textContent = "";
      }

      document
        .getElementById("generate-primes-btn")
        .addEventListener("click", generatePrimeNumbers);

      // Adapting the Encryption function to handle both ASCII and Numeric encryption.
      document.getElementById("encrypt-btn").addEventListener("click", function () {
        let message = document.getElementById("inputMessage").value;
        let warningMsg = document.getElementById("enwarningMsg");

        // Check if input is empty
        if (message == "") {
          warningMsg.textContent =
            "Invalid input. Please input a message for encryption.";
          return;
        }

        if (document.getElementById("messageMode").value === "numeric") {
          // Numeric encryption, so input must not contain non-numeric characters
          if (!/^\d+$/.test(message)) {
            warningMsg.textContent =
              "Invalid input. Please input numeric characters only.";
            return;
          } else {
            warningMsg.textContent = ""; // Reset any previous warning
            let toEncrypt = BigInt(message);
            message = modularExponentiation(
              toEncrypt,
              BigInt(e),
              BigInt(n)
            ).toString();
          }
        } else {
          // ASCII mode
          message = message
            .split("")
            .map((ch) => {
              let toEncrypt = BigInt(ch.charCodeAt(0));
              return modularExponentiation(
                toEncrypt,
                BigInt(e),
                BigInt(n)
              ).toString();
            })
            .join(" ");
        }
        document.getElementById("encryptionResult").textContent = message;
      });

      // Adapting the Decryption function to handle both ASCII and Numeric decryption.
      document
        .getElementById("decrypt-btn")
        .addEventListener("click", function () {
          let encryptedMessage = document.getElementById("encryptionResult")
            .textContent;
          let decryptedMessage = "";

          if (document.getElementById("messageMode").value === "ascii") {
            decryptedMessage = encryptedMessage
              .split(" ")
              .map((element) =>
                String.fromCharCode(
                  Number(
                    modularExponentiation(
                      BigInt(element),
                      BigInt(d),
                      BigInt(n)
                    )
                  )
                )
              )
              .join("");
          } else {
            // Numeric mode
            decryptedMessage = Number(
              modularExponentiation(BigInt(encryptedMessage), BigInt(d), BigInt(n))
            );
          }
          document.getElementById("decryptionResult").textContent =
            decryptedMessage;
        });

      function generateRandomPrimeNumbers() {
        const warningMsg = document.getElementById("warningMsg");
        const pBitSizeElement = document.getElementById("pBitSize");
        const qBitSizeElement = document.getElementById("qBitSize");

        let p = Math.floor(Math.random() * maxRange) + 1;
        p = closestPrime(p);

        let q = Math.floor(Math.random() * maxRange) + 1;
        q = closestPrime(q);

        // Rest of the code for generating primes, calculating n, e, d is same as for manual generation
        n = p * q;
        document.getElementById("multiplyPrimes").textContent = n;
        const totient = (p - 1) * (q - 1);

        e = 2;
        while (gcd(e, totient) !== 1) {
          e++;
        }
        document.getElementById("encryptionExponent").textContent = e;

        d = 1;
        while ((e * d) % totient !== 1 || e === d) {
          d++;
        }
        document.getElementById("decryptionExponent").textContent = d;
        document.getElementById("p").value = p;
        document.getElementById("q").value = q;

        // Calculate bit size for P and Q
        const pBitSize = Math.ceil(Math.log2(p + 1));
        const qBitSize = Math.ceil(Math.log2(q + 1));

        pBitSizeElement.innerHTML = `${pBitSize} bits`;
        qBitSizeElement.innerHTML = `${qBitSize} bits`;

        const modulusBitSize = Math.ceil(Math.log2(n + 1));
        document.getElementById("modulusBitSize").innerHTML = `${modulusBitSize} bits`;

        warningMsg.textContent = "";
      }

      // Add event listener for "Generate Primes Randomly" button
      document
        .getElementById("generate-primes-random-btn")
        .addEventListener("click", generateRandomPrimeNumbers);
      document.getElementById("maxRange").value = maxSize;
    </script>
  </body>
</html>