Vertical Dot Navigation

Vertical Dot Navigation

I am working on a vertical dot navigation and have been able to have the hover label work, as well as navigating to the different sections on click. Where I am struggling, is having the active dot show when scrolling through the continuous page sections. Currently, when I start the scroll, all the dot navigations fill in, rather than just the one dot nav that is connected to the section. I have tried using  $('this').addClass('active'); but as you can see, it still does not address the issue. 

Here is a link to the jsfiddle that I am working on.


Thank you in advance for your time and assistance in helping me understand what I am missing.