function gradioApp() {
  const elems = document.getElementsByTagName("gradio-app");
  const elem = elems.length == 0 ? document : elems[0];

  if (elem !== document)
    elem.getElementById = function (id) {
      return document.getElementById(id);
    };
  return elem.shadowRoot ? elem.shadowRoot : elem;
}

function get_uiCurrentTab() {
  return gradioApp().querySelector("#tabs button.selected");
}

function get_uiCurrentTabContent() {
  return gradioApp().querySelector(
    '.tabitem[id^=tab_]:not([style*="display: none"])'
  );
}

uiUpdateCallbacks = [];
uiLoadedCallbacks = [];
uiTabChangeCallbacks = [];
optionsChangedCallbacks = [];
let uiCurrentTab = null;

function onUiUpdate(callback) {
  uiUpdateCallbacks.push(callback);
}
function onUiLoaded(callback) {
  uiLoadedCallbacks.push(callback);
}
function onUiTabChange(callback) {
  uiTabChangeCallbacks.push(callback);
}
function onOptionsChanged(callback) {
  optionsChangedCallbacks.push(callback);
}

function runCallback(x, m) {
  try {
    x(m);
  } catch (e) {
    (console.error || console.log).call(console, e.message, e);
  }
}
function executeCallbacks(queue, m) {
  queue.forEach(function (x) {
    runCallback(x, m);
  });
}

var executedOnLoaded = false;

document.addEventListener("DOMContentLoaded", function () {
  var mutationObserver = new MutationObserver(function (m) {
    if (!executedOnLoaded && gradioApp().querySelector("#txt2img_prompt")) {
      executedOnLoaded = true;
      executeCallbacks(uiLoadedCallbacks);
    }

    executeCallbacks(uiUpdateCallbacks, m);
    const newTab = get_uiCurrentTab();
    if (newTab && newTab !== uiCurrentTab) {
      uiCurrentTab = newTab;
      executeCallbacks(uiTabChangeCallbacks);
    }
  });
  mutationObserver.observe(gradioApp(), { childList: true, subtree: true });
});

/**
 * Add a ctrl+enter as a shortcut to start a generation
 */
document.addEventListener("keydown", function (e) {
  var handled = false;
  if (e.key !== undefined) {
    if (e.key == "Enter" && (e.metaKey || e.ctrlKey || e.altKey))
      handled = true;
  } else if (e.keyCode !== undefined) {
    if (e.keyCode == 13 && (e.metaKey || e.ctrlKey || e.altKey)) handled = true;
  }
  if (handled) {
    button = get_uiCurrentTabContent().querySelector("button[id$=_generate]");
    if (button) {
      button.click();
    }
    e.preventDefault();
  }
});

/**
 * checks that a UI element is not in another hidden element or tab content
 */
function uiElementIsVisible(el) {
  let isVisible = !el.closest(".\\!hidden");
  if (!isVisible) {
    return false;
  }

  while ((isVisible = el.closest(".tabitem")?.style.display !== "none")) {
    if (!isVisible) {
      return false;
    } else if (el.parentElement) {
      el = el.parentElement;
    } else {
      break;
    }
  }
  return isVisible;
}