Maybe I need the ability to access the parent node?

[liby]

Assume we have the following structure(in the real-world usage id is not required to include title):

  <h1 id="title_1">Title 1</h1>
  <div id="title_1_1">
    <h2>Title 1.1</h2>
  </div>
  <h3 id="title_1_1_1">Title 1.1.1</h3>
  <h2 id="title_1_2">Title 1.2</h2>
  <h2 id="title_1_3">Title 1.3</h2>
  <h3 id="title_1_3_1">Title 1.3.1</h3>
  <h1 id="title_2">Title 2</h1>
  <h2 id="title_2_1">Title 2.1</h2>
  <h1 id="title_3">Title should escape &, ', < and "</h1>
  <h1 id="title_4"><a name="chapter1">Chapter 1 should be printed to toc</a></h1>

I need to get all the <header> tag, finally, the following structure is generated:

[
  { text: 'Title 1', id: 'title_1', level: 1 },
  { text: 'Title 1.1', id: 'title_1_1', level: 2 },
  { text: 'Title 1.1.1', id: 'title_1_1_1', level: 3 },
  { text: 'Title 1.2', id: 'title_1_2', level: 2 },
  { text: 'Title 1.3', id: 'title_1_3', level: 2 },
  { text: 'Title 1.3.1', id: 'title_1_3_1', level: 3 },
  { text: 'Title 2', id: 'title_2', level: 1 },
  { text: 'Title 2.1', id: 'title_2_1', level: 2 },
  { text: 'Title should escape &, ', < and "', id: 'title_3', level: 1 },
  { text: 'Chapter 1 should be printed to toc', id: 'title_4', level: 1 },
]

But it is a bit special for <h2>Title 1.1</h2> because it has no id attribute and needs to be obtained from its parent node.
Now I don't have a good idea. Maybe I missed something.
cc 🙏 @y21