const toolButtons = document.querySelectorAll(".tool-button");
const panels = document.querySelectorAll(".panel");

document.addEventListener("click", async (event) => {
  const button = event.target.closest("[data-copy-value]");
  if (!button) {
    return;
  }

  const value = button.dataset.copyValue || "";
  const originalLabel = button.textContent;

  try {
    await copyText(value);
    button.textContent = "Copied";
    button.classList.add("copied");
    setTimeout(() => {
      button.textContent = originalLabel;
      button.classList.remove("copied");
    }, 1500);
  } catch (error) {
    button.textContent = "Copy failed";
    setTimeout(() => {
      button.textContent = originalLabel;
    }, 1500);
  }
});

toolButtons.forEach((button) => {
  button.addEventListener("click", () => {
    const target = button.dataset.tool;

    toolButtons.forEach((item) => item.classList.remove("active"));
    panels.forEach((panel) => panel.classList.remove("active"));

    button.classList.add("active");
    document.getElementById(target).classList.add("active");
  });
});

document.getElementById("tls-form").addEventListener("submit", async (event) => {
  event.preventDefault();
  const form = new FormData(event.currentTarget);
  const action = event.submitter?.value || "generate";

  await submitJSON("/api/tls/generate", {
    commonName: form.get("commonName"),
    organization: form.get("organization"),
    organizationalUnit: form.get("organizationalUnit"),
    locality: form.get("locality"),
    state: form.get("state"),
    country: form.get("country"),
    dnsNames: form.get("dnsNames"),
    validDays: Number(form.get("validDays")),
    keySize: Number(form.get("keySize")),
  }, renderTLSResult, document.getElementById("tls-result"), (data) => {
    if (action === "download") {
      downloadBase64File(data.zipBase64, data.zipFilename || "tls-materials.zip", "application/zip");
    }
  });
});

document.getElementById("dns-form").addEventListener("submit", async (event) => {
  event.preventDefault();
  const form = new FormData(event.currentTarget);

  await submitJSON("/api/dns/lookup", {
    host: form.get("host"),
  }, renderDNSResult, document.getElementById("dns-result"));
});

document.getElementById("ssl-form").addEventListener("submit", async (event) => {
  event.preventDefault();
  const form = new FormData(event.currentTarget);

  await submitJSON("/api/ssl/check", {
    url: form.get("url"),
  }, renderSSLResult, document.getElementById("ssl-result"));
});

document.getElementById("pem-form").addEventListener("submit", async (event) => {
  event.preventDefault();
  const form = new FormData(event.currentTarget);

  await submitJSON("/api/pem/check", {
    pem: form.get("pem"),
  }, renderPEMResult, document.getElementById("pem-result"));
});

async function submitJSON(url, payload, renderer, target, onSuccess) {
  setLoading(target);

  try {
    const response = await fetch(url, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
      },
      body: JSON.stringify(payload),
    });

    const data = await response.json();
    if (!response.ok) {
      throw new Error(data.error || "Request failed");
    }

    target.classList.remove("empty", "error");
    target.innerHTML = renderer(data);
    if (onSuccess) {
      onSuccess(data);
    }
  } catch (error) {
    target.classList.remove("empty");
    target.classList.add("error");
    target.textContent = error.message;
  }
}

function setLoading(target) {
  target.classList.remove("error");
  target.classList.add("empty");
  target.textContent = "Working...";
}

function renderTLSResult(data) {
  return `
    ${renderMetaGrid([
      ["Subject", escapeHTML(data.subject)],
      ["Issuer", escapeHTML(data.issuer)],
      ["Serial Number", escapeHTML(data.serialNumber)],
      ["Valid From", escapeHTML(data.notBefore)],
      ["Valid Until", escapeHTML(data.notAfter)],
      ["Certificate Type", escapeHTML(data.isSelfSigned ? "Self-Signed" : "Signed")],
      ["Key Size", escapeHTML(`${data.keySize || ""}-bit RSA`)],
      ["Organization", escapeHTML((data.organization || []).join(", "))],
      ["OU", escapeHTML((data.ou || []).join(", "))],
      ["Locality", escapeHTML((data.locality || []).join(", "))],
      ["State / Province", escapeHTML((data.state || []).join(", "))],
      ["Country", escapeHTML((data.country || []).join(", "))],
      ["DNS Names", escapeHTML((data.dnsNames || []).join(", "))],
    ])}
    ${renderCopyablePEMBlock("Public Key PEM", data.publicKeyPem)}
    ${renderCopyablePEMBlock("Certificate Signing Request", data.csrPem)}
    ${renderCopyablePEMBlock("Self-Signed Certificate PEM", data.selfSignedCertificatePem || data.certificatePem)}
    ${renderCopyablePEMBlock("Private Key PEM", data.privateKeyPem)}
  `;
}

function renderDNSResult(data) {
  return `
    ${renderMetaGrid([
      ["Host", escapeHTML(data.host)],
      ["CNAME", escapeHTML(data.cname || "None")],
    ])}
    ${renderListBlock("A / AAAA", data.ips)}
    ${renderListBlock("TXT", data.txt)}
    ${renderListBlock("NS", data.ns)}
    ${renderListBlock("MX", (data.mx || []).map((record) => `${record.host} (pref ${record.pref})`))}
    ${renderErrorBlock(data.errors)}
  `;
}

function renderSSLResult(data) {
  const leaf = (data.chain || [])[0] || {};

  return `
    ${renderMetaGrid([
      ["Requested URL", escapeHTML(data.url)],
      ["Server Name", escapeHTML(data.serverName)],
      ["TLS Version", escapeHTML(data.version)],
      ["Cipher Suite", escapeHTML(data.cipherSuite)],
      ["ALPN", escapeHTML(data.negotiatedProtocol || "None")],
      ["Leaf Subject", escapeHTML(leaf.subject || "")],
      ["Leaf Issuer", escapeHTML(leaf.issuer || "")],
      ["Leaf Valid Until", escapeHTML(leaf.notAfter || "")],
    ])}
    <div class="record-block">
      <h3>Certificate Chain</h3>
      <pre>${escapeHTML(JSON.stringify(data.chain, null, 2))}</pre>
    </div>
    <div class="record-block">
      <h3>Leaf Certificate PEM</h3>
      <pre>${escapeHTML(data.certificatePem)}</pre>
    </div>
  `;
}

function renderPEMResult(data) {
  return `
    ${renderMetaGrid([
      ["PEM Blocks", escapeHTML(String(data.count || 0))],
    ])}
    ${(data.blocks || []).map((block, index) => `
      <div class="record-block">
        <h3>Block ${index + 1}: ${escapeHTML(block.kind || "unknown")} (${escapeHTML(block.pemType || "")})</h3>
        ${renderMetaGrid([
          ["Subject", escapeHTML(block.subject || "None")],
          ["Issuer", escapeHTML(block.issuer || "None")],
          ["Serial Number", escapeHTML(block.serialNumber || "None")],
          ["Valid From", escapeHTML(block.notBefore || "None")],
          ["Valid Until", escapeHTML(block.notAfter || "None")],
          ["Algorithm", escapeHTML(block.algorithm || block.publicKeyAlgorithm || "None")],
          ["Signature Algorithm", escapeHTML(block.signatureAlgorithm || "None")],
          ["Size", escapeHTML(block.size ? `${block.size}-bit` : "None")],
          ["Curve", escapeHTML(block.curve || "None")],
          ["DNS Names", escapeHTML((block.dnsNames || []).join(", ") || "None")],
          ["Emails", escapeHTML((block.emailAddresses || []).join(", ") || "None")],
          ["CA", escapeHTML(block.isCA === true ? "Yes" : block.isCA === false ? "No" : "None")],
        ])}
      </div>
    `).join("")}
  `;
}

function renderCopyablePEMBlock(title, value) {
  return `
    <div class="record-block">
      <div class="record-heading">
        <h3>${escapeHTML(title)}</h3>
        <button type="button" class="copy-button" data-copy-value="${escapeHTML(value || "")}">Copy</button>
      </div>
      <pre>${escapeHTML(value || "")}</pre>
    </div>
  `;
}

function renderMetaGrid(items) {
  return `
    <div class="meta-grid">
      ${items.map(([label, value]) => `
        <div class="meta-item">
          <strong>${label}</strong>
          <span>${value || "None"}</span>
        </div>
      `).join("")}
    </div>
  `;
}

function renderListBlock(title, values = []) {
  return `
    <div class="record-block">
      <h3>${title}</h3>
      ${values.length ? `<ul>${values.map((value) => `<li>${escapeHTML(value)}</li>`).join("")}</ul>` : "<p>No records returned.</p>"}
    </div>
  `;
}

function renderErrorBlock(errors = {}) {
  const entries = Object.entries(errors);
  if (!entries.length) {
    return "";
  }

  return `
    <div class="record-block">
      <h3>Lookup Notes</h3>
      <ul>${entries.map(([kind, message]) => `<li>${escapeHTML(kind)}: ${escapeHTML(message)}</li>`).join("")}</ul>
    </div>
  `;
}

async function copyText(value) {
  if (navigator.clipboard && window.isSecureContext) {
    await navigator.clipboard.writeText(value);
    return;
  }

  const textarea = document.createElement("textarea");
  textarea.value = value;
  textarea.setAttribute("readonly", "");
  textarea.style.position = "absolute";
  textarea.style.left = "-9999px";
  document.body.appendChild(textarea);
  textarea.select();

  const success = document.execCommand("copy");
  document.body.removeChild(textarea);

  if (!success) {
    throw new Error("copy failed");
  }
}

function downloadBase64File(base64Value, filename, mimeType) {
  const binary = atob(base64Value || "");
  const bytes = new Uint8Array(binary.length);

  for (let index = 0; index < binary.length; index += 1) {
    bytes[index] = binary.charCodeAt(index);
  }

  const blob = new Blob([bytes], { type: mimeType });
  const url = URL.createObjectURL(blob);
  const link = document.createElement("a");
  link.href = url;
  link.download = filename;
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
  URL.revokeObjectURL(url);
}

function escapeHTML(value) {
  return String(value ?? "")
    .replaceAll("&", "&amp;")
    .replaceAll("<", "&lt;")
    .replaceAll(">", "&gt;")
    .replaceAll('"', "&quot;")
    .replaceAll("'", "&#39;");
}