script.js

function generateDOIs(prefix, count) {
  const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  const integers = "0123456789";

  var outputDOIs = [];
  for (let i = 0; i < count; i++) {
    let letters = "";
    let numbers = "";
    for (let j = 0; j < 4; j++) {
      letters += alphabet[Math.floor(Math.random() * alphabet.length)];
    }

    for (let j = 0; j < 4; j++) {
      numbers += integers[Math.floor(Math.random() * integers.length)];
    }

    outputDOIs.push(`${prefix}/${letters}${numbers}`);
  }

  return outputDOIs;
}

document.addEventListener("DOMContentLoaded", (event) => {
  document.getElementById("generate").addEventListener("click", () => {
    const prefix = document.getElementById("prefix").value.trim();
    const count = parseInt(document.getElementById("count").value);
    const error = document.getElementById("error");

    if (!prefix) {
      error.textContent = "Please enter a prefix";
      error.style.display = "block";
      return;
    }

    if (!count || count < 1 || count > 1000) {
      error.textContent = "Please enter a number between 1 and 1000";
      error.style.display = "block";
      return;
    }

    console.log(count);
    const DOIs = generateDOIs(prefix, count);

    document.getElementById("output").value = DOIs.join("\n");
    document.getElementById("results").style.display = "block";

    document.getElementById("copy-btn").addEventListener("click", () => {
      const text = document.getElementById("output").value;
      navigator.clipboard.writeText(text).then(() => {
        const btn = document.getElementById("copy-btn");
        btn.textContent = "Copied!";
        btn.classList.add("copied");
        setTimeout(() => {
          btn.textContent = "Copy";
          btn.classList.remove("copied");
        }, 2000);
      });
    });
  });
});