Mask to telephone in pure JS

const input = document.getElementById("input");

function telephone(v) {
    v = v.replace(/\D/g, "");
    v = v.replace(/^(\d\d)(\d)/g, "($1) $2");
    v = v.replace(/(\d{4})(\d)/, "$1-$2");
    return v
}

input.addEventListener("input", () => {
  let value = telephone(input.value);

  input.value = value;
});