Overscroll to switch pages

import.coffee

				start = undefined
				breakTimeout = undefined
				$overscroll_down_indicator = jQuery(".overscroll_down_indicator")
				$overscroll_up_indicator = jQuery(".overscroll_up_indicator")
				break_time = 100#ms
				release_threshold = 300#ms
				overscroll_break = ->
					$overscroll_down_indicator.css("display","none")
					$overscroll_up_indicator.css("display","none")
					start = undefined
					breakTimeout = undefined
				overscroll = (e)->
					console.dir e
					if jQuery(window).scrollTop() + jQuery(window).height() - jQuery("body").height() >= 0
						direction = "down"
					else if jQuery(window).scrollTop() <= 0
						direction = "up"
					else
						direction = undefined

					if direction?
						clearTimeout(breakTimeout)
						breakTimeout = setTimeout overscroll_break, break_time
						now = jQuery.now()
						start = now unless start?
						elapsed = now - start
						if direction is "up"
							$overscroll_up_indicator.css
								display: "block"
								top: "#{50 * jQuery.easing["easeOutQuart"](null, elapsed, 0 , 1, release_threshold) - 25}px"
						if direction is "down"
							$overscroll_down_indicator.css
								display: "block"
								bottom: "#{50 * jQuery.easing["easeOutQuart"](null, elapsed, 0 , 1, release_threshold) - 25}px"
						if elapsed > release_threshold
							go_in_direction direction
							overscroll_break()
					else
						overscroll_break()
					return true

				window.onwheel = overscroll
				window.onmousewheel = overscroll