var sorting = function() {
    $('#sort_order').change(function() {
	var sort_by = $('#sort_by').val();
        var sort_order = $('#sort_order').val();
	if(sort_by != '') {
	    window.location.href = sort_by + sort_order;
	}
    });

    $('#sort_by').change(function() {
	var sort_by = $('#sort_by').val();
        var sort_order = $('#sort_by option:selected').attr('data-sort-order');
	if(sort_by != '') {
	    window.location.href = sort_by + sort_order;
	}
    });
};

$(document).ready(function() {
    sorting();
});