Google Docs Add today's date with heading

js

function onOpen() {
  var ui = DocumentApp.getUi();
  
  ui.createMenu('Services')
      .addItem('Add Day', 'addNewDay')
      .addToUi();
}

function formatTwoDigit(n) {
  return n < 10 ? '0' + n : '' + n; 
}

function addNewDay() {
  let cursor = DocumentApp.getActiveDocument().getCursor();

  if (!cursor) {
    return;
  }

  let date = new Date();
  let dateStr = formatTwoDigit(date.getDate()) + '.' + (formatTwoDigit(date.getMonth() + 1)) + '.' + date.getFullYear();
  let element = cursor.insertText(dateStr);

  if (element) {
    element.setBold(true);
    
    let parent = element.getParent();
    let style = {};
    style[DocumentApp.Attribute.HEADING] = DocumentApp.ParagraphHeading.HEADING4;

    parent.setAttributes(style);
  }
}