Infinitely loads products on to a collection page

productsInfiniteLoad.js

$(document).ready(function() {
	var collectionURL = $('.collection-main').attr('data-collection-url');
	var collectionPages = $('.collection-main').attr('data-collection-pages');
	var ajaxLoadPageIndex = 2;
	var ajaxIsRunning = false;

	$(window).scroll(function(){
		if ($(document).scrollTop() > 500) {
			infiniteLoadProducts();
		}
	});
});

function infiniteLoadProducts() {
	if (ajaxLoadPageIndex <= collectionPages) {	
		ajaxLoadProducts();		
	}
}

function ajaxLoadProducts() {
	if (!ajaxIsRunning) {
		ajaxIsRunning = true;
		$('.collection-main__loader').fadeIn();
		$.ajax({
			type: 'GET',
			url: collectionURL + '?page=' + ajaxLoadPageIndex,
			success: function(data) {
				var filteredData = $(data).find('.product');
				var currentScrollPosition = $(document).scrollTop();
				var i = 1;
				
				filteredData.insertBefore($('.collection-main__loader'));   
				$(document).scrollTop(currentScrollPosition);

				$('.product').each(function(){
					$(this).attr('data-product-index', i++);
				});

				++ajaxLoadPageIndex;
			},
			complete: function() {
				ajaxIsRunning = false;
				infiniteLoadProducts();
				$('.collection-main__loader').fadeOut();
			},
			dataType: 'html'
		});
	} else {
		return false;
	}
}