NodeJS Public Client

//Public/Client JS
var socket = null;
var identifier = null;
$(document).ready(function() {
    var currentNum = 0;
    function roll(num) {
        var numWidth = 1050/15;

        var layout = [1, 14, 2, 13, 3, 12, 4, 0, 11, 5, 10, 6, 9, 7, 8];

        function getMoves() {
            let to = layout.indexOf(num);
            let at = layout.indexOf(currentNum);

            if(to > at)
            {return (to - at);}
            else
            {return (layout.length - at + to);}
        }

        var currentPos = parseInt($('#case').css( "background-position" ).split(" ")[0].slice(0, -2));
        currentPos ? null : currentPos = 0;
        $('#case').animate({
            "background-position": currentPos-2100-(getMoves()*numWidth),
        }, 3000);
        currentNum = num;
        setTimeout(function() {
            if($("#past .ball").length >= 10)
            {
            $("#past .ball").first().remove();
            }
            if (num == 0)
            {
                $(".ball").last().after("<div class='ball ball-0'>" + num + "</div>");
            }
            else if (num <= 7)
            {;
                 $(".ball").last().after("<div class='ball ball-1'>" + num + "</div>");
            }
            else
            {
               $(".ball").last().after("<div class='ball ball-8'>" + num + "</div>");
            }
            $.each($('.list-group-item'), function (index, value) {
                $(this).remove();
            });
        }, 3000);
    }

    identifier = $('meta[name="identifier"]').attr('content');
    if(!socket)
    {
        if(!identifier)
        {
            console.log("User not logged in.");
        }
        else
        {
            socket = io("localhost:8000");
            socket.on('connect', function(msg) {
                console.log("Connected!");
                socket.emit('authenticate', identifier);
            });
        }
    }
    else
    {
        console.log("Connection already exists.");
    }
    socket.on('roll', function(rolledNumber)
    {
        roll(rolledNumber);
        //$('#banner').html(timer + '<span style="font-size:17px">S</span>')
    });
    socket.on('updateTime', function(timer)
    {
        $(".timer").width((timer/20)*100+"%");
        //$('#banner').html(timer + '<span style="font-size:17px">S</span>')
    });
    socket.on('users', function(num)
    {
        $('.users-online').html(num);
    });
});