logic of sticky footer

sticky_footer.js

jQuery(document).ready(function ($) {

	var contentHeight = $('.above-footer-wrapper').height() - $('.fusion-footer.ac-footer').height();
	var windowHeight = $(window).height();
	var scrollTop = $(window).scrollTop();
	var stickyFooter = $('.fusion-footer-sticky');

	function checkFooterSticky() {
			scrollTop = $(window).scrollTop(); 
			console.log('sc:',scrollTop,';ch:',contentHeight,';wh:',windowHeight);
		//	  0 < 6000 && 0 > 444
		if( (scrollTop < contentHeight && scrollTop > windowHeight) && !stickyFooter.hasClass('show-footer')){
			stickyFooter.addClass('show-footer');
			console.log('r');
			//     6001 > 6000 && 6001 > 444 || 6001
		}else if( (scrollTop > contentHeight && scrollTop > windowHeight) && stickyFooter.hasClass('show-footer') || scrollTop < windowHeight ){
			stickyFooter.removeClass('show-footer');
			console.log('a');
		}
	}

	checkFooterSticky();

	$(window).on({
		'resize': function (event) {
			contentHeight = $('.above-footer-wrapper').height() - $('.fusion-footer.ac-footer').height();
			windowHeight = $(window).height();
		},
		'scroll': checkFooterSticky,
		'load': function (event) {
			scrollTop = $(window).scrollTop();
			if(scrollTop > windowHeight) stickyFooter.removeClass('show-footer');
		}
	});
});