How to apply mask to string value not element

[JoshKasap]

All the examples and use cases seem to be on how to use the plugin to apply a mask to the value of an input field. However, I've run into a situation where I need to apply the mask to a raw string value and get the resulting mask.

for example I currently have this custom mask

function getPhoneMask (input, e, field, options){
    let unmaskedVal = input.replace(/[^\d]/g, '');
    let masks = ['(000) 000-00000000000', '+0 (000) 000-00000000', '+00 (000) 000-0000000', '+000 (000) 000-000000', '+0000 (000) 000-00000', '+00000 (000) 000-0000'];
    let mask = unmaskedVal.length == 15 ? masks[5]: unmaskedVal.length == 14 ? masks[4] : unmaskedVal.length == 13 ? masks[3] : unmaskedVal.length == 12 ? masks[2]: unmaskedVal.length == 11 ? masks[1] : masks[0];

    console.log(`mask: ${mask}`);
    return mask
}

$('.phoneMask').mask(getPhoneMask, {
    onKeyPress: function(input, e, field, options) {
        let mask = getPhoneMask(input, e, field, options);
        field.mask(mask, options);
    }
});

This finds the value of each element with the .phoneMask class and applies the mask on load and on keypress.

however, let say i have a random string "1231231234" This value is not the value of an input element but just the value of some variable in my code. How can i apply my custom mask just to this value so that i would end up with (123) 123-1234