Preliminary but works, even though I'm probably doing some stuff wrong/dumbly. Basically, "if input is idle for less than two minutes, then grep the active window, if it's the same active window for two times in three 30-second time-windows, count it as active ; after looping N times, show a rudimentary bar graph of how many times each logged window was used."
It would be nicer to actually transform the counting of each program in a percentage of the total, but it's good...