Append Coordinates of each Element in a JSON - node.js

Question

this is partially a follow-up to this question: Filtering Arrays in NodeJS without knowing where the value's location is
I got the JSON output but now I'm required to append the coordinates of each element to its respective element in the JSON.
I tried to use page.$(input[type='']) selector while having a variable instead of type for each key, and having the value being the value of said key, the issue is, I only got one type of output, that is the first element with type text, it returned null when element type was anything but text (i.e. element for example), and it, of course, didn't cycle through all elements with type text (I do know why), I tried using page.$$(input[type='']) but I couldn't figure out much how to use elementHandle on each object & lastly I can't figure out how to append back the coordinates to each element without losing the original hierarchy.
For reference: Here's a sample of the outputted JSON:
[
{
"type": "element",
"tagName": "form",
"attributes": [
{
"key": "action",
"value": "/action_page.php"
},
{
"key": "target",
"value": "_blank"
}
],
"children": [
{
"type": "text",
"content": "\nFirst name:"
},
{
"type": "element",
"tagName": "input",
"attributes": [
{
"key": "type",
"value": "text"
},
{
"key": "name",
"value": "firstname"
},
{
"key": "value",
"value": "John"
}
],
"children": []
},
{
"type": "text",
"content": "\nLast name:"
},
{
"type": "element",
"tagName": "input",
"attributes": [
{
"key": "type",
"value": "text"
},
{
"key": "name",
"value": "lastname"
},
{
"key": "value",
"value": "Doe"
}
],
"children": []
},
{
"type": "element",
"tagName": "input",
"attributes": [
{
"key": "type",
"value": "submit"
},
{
"key": "value",
"value": "Submit"
}
],
"children": []
},
{
"type": "text",
"content": "\n"
}
]
please note that this output isn't uniform and this will be used on multiple pages with different layouts, so the answer does need to be as adaptable as possible.