(function () {
  const notice = document.querySelector("[data-version-notice]");
  const reload = document.querySelector("[data-version-reload]");
  const documentShell = document.querySelector("[data-document-path][data-document-hash]");

  if (!notice || !reload || !documentShell || !window.WebSocket) {
    return;
  }

  const currentPath = documentShell.getAttribute("data-document-path");
  const currentHash = documentShell.getAttribute("data-document-hash");
  const protocol = window.location.protocol === "https:" ? "wss:" : "ws:";
  const socket = new WebSocket(protocol + "//" + window.location.host + "/ws");

  socket.addEventListener("message", function (event) {
    let payload;
    try {
      payload = JSON.parse(event.data);
    } catch {
      return;
    }

    if (payload.type !== "document_version" || !payload.data) {
      return;
    }

    if (payload.data.path === currentPath && payload.data.hash !== currentHash) {
      notice.hidden = false;
    }
  });

  reload.addEventListener("click", function () {
    window.location.reload();
  });
})();