How do I parse the indentation level of a string into a JSON Object?

I’d like to be able to parse a string into a JSON Object, something like this (the text can be anything, I’m just putting them like this so you can see the structure):

A
  A-A
  A-B
    A-B-A
    A-B-B
  A-C
    A-C-A
B

into a json object, structured like this:

[
  {
    "root": "A",
    "content": [
      { "root": "A-A", "content": [] },
      {
        "root": "A-B",
        "content": [
          { "root": "A-B-A", "content": [] },
          { "root": "A-B-B", "content": [] }
        ]
      },
      {
        "root": "A-C",
        "content": [
          { "root": "A-C-A", "content": [] }
        ]
      }
    ]
  },
  { "root": "B", "content": [] }
]

So far, I have the following, but I’m not sure if this is the best way of doing it. Maybe a recursive approach would be better?

  let body = [];
  let indentStack = [0];
  for (let line of input.split('n')) { // input is the string I'd like to parse
    if (line.trim() == '') continue; // skips over empty lines
    let indent = line.match(/^ +/);
    indent = indent ? indent[0].length : 0; // matches the first group of spaces with regex, gets the indent level of this line
    if (indentStack[indentStack.length-1] != indent) 
      if (indentStack.includes(indent)) indentStack.length = indentStack.indexOf(indent)+1; // remove all indent levels after it as it's returned back to a higher level
      else stack.push(indent);
    console.log(`${(indent + '[' + indentStack.join() + ']').padEnd(10, ' ')}: ${line}`); // debugging
      
    if (indentStack.length == 1) body.push({ root: line, content: [] });
    else {
      body[body.length-1].content.push({ root: line.substring(indent), content: [] })
    }
  }
  console.log(body)