Javascript Phone number validation Paratheses sign

I did some searching and there where others asking this question and answers to it but none that seemed to fit what I was trying to do. Basically I'm working on a validation of the phone entry that accepts (123)4567890 as an entry. I've already implemented one that accepts a simple number string such as 1234567890 and one with dashes 123-456-7890. I know I'm making a simple mistake somewehre but I can't figure out what I'm doing wrong.

Here's the phone number with dashes form that is working:

//Validates phone number with dashes. 
 function isTwelveAndDashes(phone) {
 
     if (phone.length != 12) return false;
 
     var pass = true;
 
     for (var i = 0; i < phone.length; i++) {
         var c = phone.charAt(i);
 
         if (i == 3 || i == 7) {
             if (c != '-') {
                 pass = false;
             }
         }
         else {
             if (!isDigit(c)) {
                 pass = false;
             }
         }
     }
 
     return pass;
 }?
 

and this is the one I can't manage to work out.

function isTwelveAndPara(phone) {
     if (phone.length != 12) return false;
 
     var pass = true;
 
     for (var i = 0; i < phone.length; i++) {
         var c = phone.charAt(i);
 
         if (i == 0) {
             if (c != '(') {
                 pass = false;
             }
         }
 
         if (i == 4) {
             if (c != ')') {
                 pass = false;
             }
         }
         else {
             if (!isDigit(c)) {
                 pass = false;
             }
         }
     }
 
     return pass;
 }?
 

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