Constellation AJAX load with effect

/**
 * Binds a loading layer effect to an ajax call
 * @param  jqXHR    deferred the jqXHR object returned by an $.ajax() call
 * @param  function retry    function to call to re-lauch the request
 * @return jQuery
 */
$.fn.ajaxWithEffect = function(deferred, retry)
{
    // Add effect layer
    this.addEffectLayer({
        message: $.fn.ajaxWithEffect.defaults.message
    });

    // Callbacks
    deferred.done(function()
    {
        // Get the effect layer
        var refElement = getNodeRefElement(this);
        var layer = $(refElement).next('.loading-mask');
        var span = layer.children('span');

        // Remove effect layer
        layer.stop(true);
        span.stop(true);
        var currentMarginTop = parseInt(span.css('margin-top'));
        var marginTop = parseInt(span.css('margin-top', '').css('margin-top'));
        span.css({'marginTop':currentMarginTop+'px'}).animate({'opacity':0, 'marginTop':(marginTop-40)+'px'}, {
            'complete': function()
            {
                layer.fadeAndRemove();
            }
        });
    });
    deferred.fail(function()
    {
        // Get the effect layer
        var refElement = getNodeRefElement(this);
        var layer = $(refElement).next('.loading-mask');
        var span = layer.children('span');

        // Error layer
        if (retry)
        {
            span.addClass('error').html($.fn.ajaxWithEffect.defaults.errorMessage+'<br><a href="#">'+$.fn.ajaxWithEffect.defaults.retry+'</a> / <a href="#">'+$.fn.ajaxWithEffect.defaults.cancel+'</a>');
            span.children('a:first').click(function(event)
            {
                event.preventDefault();

                // Remove current layer
                layer.stop(true).remove();

                // Relaunch request
                retry();
            });
        }
        else
        {
            span.addClass('error').html($.fn.ajaxWithEffect.defaults.errorMessage+'<br><a href="#">'+$.fn.ajaxWithEffect.defaults.close+'</a>');
        }
        span.children('a:last').click(function(event)
        {
            event.preventDefault();

            // Remove effect layer
            layer.stop(true);
            span.stop(true);
            var currentMarginTop = parseInt(span.css('margin-top'));
            var marginTop = parseInt(span.css('margin-top', '').css('margin-top'));
            span.css({'marginTop':currentMarginTop+'px'}).animate({'opacity':0, 'marginTop':(marginTop-40)+'px'}, {
                'complete': function()
                {
                    layer.fadeAndRemove();
                }
            });
        });

        // Centering
        span.css('margin-left', -Math.round(span.outerWidth()/2));
    });

    return this;
};

// Default texts for the loading effect layer
$.fn.ajaxWithEffect.defaults = {
    message: 'Loading...',
    errorMessage: 'Error while loading',
    retry: 'Retry',
    cancel: 'Cancel',
    close: 'Close'
};