Function showDialog

src/dialogs/make-dialog-manager.ts:81–194

(
  element: LitElement & ProvideHassElement,
  dialogTag: string,
  dialogParams: unknown,
  dialogImport?: () => Promise<unknown>,
  parentElement?: LitElement,
  addHistory = true,
  dialogAnchor?: Element
)

 * @returns `true` if the dialog was shown (or could be shown), `false` if it could not be loaded.
 */
export const showDialog = async (
  element: LitElement & ProvideHassElement,
  dialogTag: string,
  dialogParams: unknown,
  dialogImport?: () => Promise<unknown>,
  parentElement?: LitElement,
  addHistory = true,
  dialogAnchor?: Element
): Promise<boolean> => {
  if (!(dialogTag in LOADED)) {
    if (!dialogImport) {
      if (__DEV__) {
        // eslint-disable-next-line
        console.warn(
          "Asked to show dialog that's not loaded and can't be imported"
        );
      }
      return false;
    }
    LOADED[dialogTag] = {
      element: dialogImport().then(() => {
        const dialogEl = document.createElement(dialogTag) as
          | HassDialogNext
          | HassDialog;

        if ("showDialog" in dialogEl) {
          // provide hass for legacy persistent dialogs
          element.provideHass(dialogEl);
        }

        dialogEl.addEventListener("dialog-closed", _handleClosed);
        dialogEl.addEventListener("dialog-closed", _handleClosedFocus);

        return dialogEl;
      }),
    };
  }

  if (addHistory) {
    const { history } = mainWindow;
    if (history.state?.dialog && !OPEN_DIALOG_STACK.length) {
      // theres is a dialog state in history, but no dialogs open
      // wait for history.back() to update the state
      await new Promise((resolve) => {
        setTimeout(resolve);
      });
      return showDialog(
        element,
        dialogTag,
        dialogParams,
        dialogImport,
        parentElement,
        addHistory,
        dialogAnchor
      );
    }
    const dialogIndex = OPEN_DIALOG_STACK.findIndex(
      (state) => state.dialogTag === dialogTag