How to formulate custom calculation script (if this is even possible).

I'm creating an interactive worksheet for a friend. 

This worksheet has 3 shapes on it: a square, circle, and triangle. As well as a 24 Hour vs day of the week chart. 

He wants there to be a custom entry in each shape that will also auto-populate as 3 selections in a dropdown menu for each hour slot. These 3 options will need to be calculated back as hours spent in each shape. 

This is what it currently looks like 

It uses:

var total = 0;

for (var i=1; i<=168; i++) {

if (this.getField("M1."+i).valueAsString=="Square") total++;

}

event.value = total;