filter.js

angular.module('isCheckout').filter('tel', function () {
    return function (tel) {
       
        if (!tel) { return ''; }

        var value = tel.toString().trim().replace(/^\+/, '');

        if (value.match(/[^0-9]/)) {
            return tel;
        }

        var country, city, number;

        switch (value.length) {
            case 1:
            case 2:
            case 3:
                city = value;
                break;

            default:
                city = value.slice(0, 3);
                number = value.slice(3);
        }

        if(number){
            if(number.length>3){
                number = number.slice(0, 3) + '-' + number.slice(3,7);
            }
            else{
                number = number;
            }

            return ("(" + city + ") " + number).trim();
        }
        else{
            return "(" + city;
        }

    };
});