// If there is a caret anywhere in the document (user entering text), returns the position of the caret in the focused element
export function getCaretPosition(): number | undefined {
  const selection = window.getSelection();
  if (selection) {
    const range = selection.getRangeAt(0);
    const clonedRange = range.cloneRange();
    return clonedRange.startOffset;
  }
}

// export function setCursorPosition(elem, pos) {
//   const range = document.createRange();
//   range.selectNode(elem);
//   range.setStart(elem, pos);
//   range.setEnd(elem, pos);
//   const selection = window.getSelection();
//   selection?.removeAllRanges();
//   selection?.addRange(range);
// }

// Move caret all the way to the right in the currently focused element
export function setRightMostCaretPosition(elem) {
  const range = document.createRange();
  range.selectNode(elem);
  if (elem.lastChild) { // if no text is entered, there is no lastChild
    range.setStart(elem.lastChild, elem.textContent.length);
    range.setEnd(elem.lastChild, elem.textContent.length);
    const selection = window.getSelection();
    selection?.removeAllRanges();
    selection?.addRange(range);
  }
}

export function focusNextElement() {
  const editable = Array.from<any>(document.querySelectorAll('input'));
  const index = editable.indexOf(document.activeElement);
  editable[index+1]?.focus();
}

export function focusPrevElement() {
  const editable = Array.from<any>(document.querySelectorAll('input'));
  const index = editable.indexOf(document.activeElement);
  const prevElem = editable[index-1]
  if (prevElem) {
    prevElem.focus();
    setRightMostCaretPosition(prevElem);
  }
}