How can I match atomic elements and their amounts in regex with Javascript?

I wanted to make a tool to parse atomic elements from a formula

so say I started with Ba(Co3Ti)2 + 3BrH20 I would first want to parse each compound in the formula, which is easy enough with let regions = str.replace(/\s/g, '').split(/\+/g);

Now for each compound, I want to identify each element and its numerical "amount"
so for the example above, for the first compound, Id want an array like this:

[
 "Ba",
 [
  "Co3",
  "Ti"
 ],
 "2"
]

and if finding sub-compounds within parenthesis isnt possible, then I could work with this:

[
 "Ba",
 "(Co3",
 "Ti)",
 "2"
]

Is this possible with regex?
This is what I’ve come up with in a few minutes..

        let compounds = str.replace(/\s/g, '').split(/\+/g);
        for (var r = 0; r < compounds.length; ++r) {
            let elements = compounds[r]
        }

>Solution :

You can use

str.match(/\(?(?:[A-Z][a-z]*\d*|\d+)\)?/g)

See the regex demo. Details:

• \(? – an optional (
• (?:[A-Z][a-z]*\d*|\d+) – either of the two options:
  • [A-Z][a-z]*\d* – an uppercase letter, then zero or more lowercase letters and then zero or more digits
  • | – or
  • \d+ – one or more digits
• \)? – an optional ).

See a JavaScript demo:

const str = 'Ba(Co3Ti)2';
const re = /\(?(?:[A-Z][a-z]*\d*|\d+)\)?/g;
let compounds = str.match(re);
console.log(compounds);