const script = `(() => {
  "use strict";
  const form = document.querySelector("[data-external-registration]");
  if (!form) return;
  const emailInput = form.querySelector("[data-auth-email]");
  const codeInput = form.querySelector("[data-auth-code]");
  const codePanel = form.querySelector("[data-auth-code-panel]");
  const sendButton = form.querySelector("[data-auth-send-code]");
  const verifyButton = form.querySelector("[data-auth-verify-code]");
  const createButton = form.querySelector("[data-auth-create-account]");
  const status = form.querySelector("[data-auth-verification-status]");
  if (!emailInput || !codeInput || !codePanel || !sendButton || !verifyButton || !createButton || !status) return;
  let verifiedEmail = "";
  function setStatus(message, state = "") {
    status.textContent = message;
    if (state) status.dataset.state = state;
    else delete status.dataset.state;
  }
  function resetVerification(message = "") {
    verifiedEmail = "";
    createButton.disabled = true;
    codeInput.value = "";
    setStatus(message);
  }
  async function postJson(path, payload) {
    const response = await fetch(path, {
      method: "POST",
      credentials: "same-origin",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(payload),
    });
    let data = {};
    try { data = await response.json(); } catch {}
    return { response, data };
  }
  emailInput.addEventListener("input", () => {
    if (emailInput.value.trim().toLowerCase() !== verifiedEmail) resetVerification();
  });
  sendButton.addEventListener("click", async () => {
    if (!emailInput.checkValidity()) {
      emailInput.reportValidity();
      return;
    }
    resetVerification("Sending a verification code...");
    sendButton.disabled = true;
    const email = emailInput.value.trim().toLowerCase();
    try {
      const { response, data } = await postJson("/api/auth/send-code", { email });
      if (response.status === 202 && data.ok === true) {
        codePanel.hidden = false;
        codeInput.required = true;
        codeInput.focus();
        setStatus("If this address can be registered, a six-digit code was sent. It expires in 5 minutes.", "success");
      } else if (response.status === 429) {
        const retryAfter = Number(data.retry_after);
        const wait = Number.isFinite(retryAfter) ? " Try again later." : "";
        setStatus("Too many verification requests." + wait, "error");
      } else {
        setStatus("Verification email is temporarily unavailable. Please try again.", "error");
      }
    } catch {
      setStatus("Verification email is temporarily unavailable. Please try again.", "error");
    } finally {
      sendButton.disabled = false;
    }
  });
  verifyButton.addEventListener("click", async () => {
    const email = emailInput.value.trim().toLowerCase();
    if (!emailInput.checkValidity()) {
      emailInput.reportValidity();
      return;
    }
    if (!/^[0-9]{6}$/.test(codeInput.value.trim())) {
      setStatus("Enter the six-digit verification code.", "error");
      codeInput.focus();
      return;
    }
    verifyButton.disabled = true;
    setStatus("Checking the verification code...");
    try {
      const { response, data } = await postJson("/api/auth/verify-code", { email, code: codeInput.value.trim() });
      if (response.ok && data.ok === true) {
        verifiedEmail = email;
        createButton.disabled = false;
        setStatus("Email verified. Complete the form and select Continue.", "success");
      } else if (response.status === 423) {
        resetVerification("Too many incorrect attempts. Request a new code after 15 minutes.");
        status.dataset.state = "error";
      } else if (response.status === 410) {
        resetVerification("This code expired. Request a new code.");
        status.dataset.state = "error";
      } else {
        setStatus("That verification code is not valid.", "error");
      }
    } catch {
      setStatus("Email verification is temporarily unavailable. Please try again.", "error");
    } finally {
      verifyButton.disabled = false;
    }
  });
  form.addEventListener("submit", (event) => {
    if (!verifiedEmail || verifiedEmail !== emailInput.value.trim().toLowerCase()) {
      event.preventDefault();
      setStatus("Verify this email address before continuing.", "error");
    }
  });
})();`;

export function GET() {
  return new Response(script, {
    headers: {
      "Cache-Control": "no-cache",
      "Content-Type": "text/javascript; charset=utf-8",
    },
  });
}