Draft of a simple jQuery plugin to upload files asynchronously via AJAX

sUpload.js

(function($) {
    var settings = {
        hoverClass: 'sUpload-hover',
        dropAreaClass: 'sUpload-drop',
        dropMessage: 'Drop file here!',
        dropAreaHeight: 200,         uploadURL: null,
        fileReaderCallback: null,
        fileUploadCallback: null,
        errorCallback: null
    },
        methods = {             init: function(options) {
                if ($.browser.msie) {
                    return;
                }
                if (options) {
                    $.extend(settings, options);                 }
                if ($('body').data('sUpload') && $('body').data('sUpload').enabled) {
                    return;
                }
                $('body').data('sUpload', {enabled: true});
                return this.each(function() {                     var that = $(this),
                        timer,
                        stopDragging = function(){
                            clearInterval (timer);
                            that.trigger('dragend');
                        };                         dropTarget = $('<div/>').addClass(settings.dropAreaClass);
                    dropTarget.append('<p>' + settings.dropMessage + '</p>');
                    //Append drop target
                    that.append(dropTarget);
                    //Bind events
                    that.bind('dragover', function (e) {                         e = e.originalEvent;
                        /*
                        if (!e.dataTransfer.types) {
                            return false;
                        }
                        if (e.dataTransfer.types.contains && !e.dataTransfer.types.contains ('Files')) {                             return false;
                        }
                        if (e.dataTransfer.types.indexOf && e.dataTransfer.types.indexOf ('Files') === -1) {
                            return false;
                        }
                        */                         if (!$(this).hasClass(settings.hoverClass)) {
                            $(this).addClass(settings.hoverClass);
                            dropTarget.show().animate({
                                height: settings.dropAreaHeight
                            }, 500);
                        }                         clearInterval (timer);
                        timer = setInterval(stopDragging, 700);
                        return false;
                    }).bind('dragend', function() {
                        $(this).removeClass(settings.hoverClass);
                        dropTarget.hide().height(0);                         return false;
                    });
                    dropTarget.bind('dragend', function(){
                        var me = $(this);
                        me.parent().removeClass(settings.hoverClass);
                        me.hide().height(0);                         return false;
                    });
                    dropTarget.bind('drop', function(e) {
                        var me = $(this), e = e.originalEvent;
                        e.preventDefault();
                        me.parent().removeClass(settings.hoverClass);                         me.hide().height(0);
                        var file = e.dataTransfer.files[0], reader, xhr, fdata;
                        if ($.isFunction(settings.fileReaderCallback)) {
                            reader = new FileReader();
                            reader.onLoad = settings.fileReaderCallback;
                            reader.readAsDataURL(file);                         }
                        fdata = new FormData();
                        fdata.append('file0', file);
                        xhr = new XMLHttpRequest();
                        xhr.open ('POST', settings.uploadURL, true);
                        xhr.onload = settings.fileUploadCallback;                         xhr.fileName = file.fileName; //So the onload callback will pass it as part of the XMLHTTPObject (this)
                        xhr.onerror = settings.errorCallback;
                        xhr.setRequestHeader('X-Requested-With', 'XMLHttpRequest');
                        xhr.send (fdata);
                        return false;
                    });                 });
            },
            updateURL: function (newURL) {
                if (!newURL) {
                    $.error('This method needs a new URL passed as a parameter.');
                    return false;                 }
                $.extend(settings, {uploadURL: newURL});
            }
        };     $.fn.sUpload = function(method) {
        if (methods[method]) {
            return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
        } else if (typeof method === 'object' || !method) {
            return methods.init.apply(this, arguments);
        } else {             $.error('Method ' + method + ' does not exist on jQuery.film');
        }
    };
})(jQuery);