jQuery.extend({
    createUploadIframe: function(id, uri) {
		//create frame
		var frameId = 'jUploadFrame' + id;
		if(window.ActiveXObject) {
		    var io = document.createElement('<iframe id="' + frameId + '" name="' + frameId + '" />');
		    if(typeof uri== 'boolean') {
		        io.src = 'javascript:false';
		    } else if(typeof uri== 'string') {
		        io.src = uri;
		    }
		} else {
		    var io = document.createElement('iframe');
		    io.id = frameId;
		    io.name = frameId;
		}
		io.style.position = 'absolute';
		io.style.top = '-1000px';
		io.style.left = '-1000px';
		document.body.appendChild(io);
		return io;		
    },
    
    createUploadForm: function(id, fileElementId) {
		//create form	
		var formId = 'jUploadForm' + id;
		var fileId = 'jUploadFile' + id;
		var form = jQuery('<form  action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');	
		var oldElement = jQuery('#' + fileElementId);
		var newElement = jQuery(oldElement).clone();
		jQuery(oldElement).attr('id', fileId);
		jQuery(oldElement).before(newElement);
		jQuery(oldElement).appendTo(form);
		//set attributes
		jQuery(form).css('position', 'absolute');
		jQuery(form).css('top', '-1200px');
		jQuery(form).css('left', '-1200px');
		jQuery(form).appendTo('body');		
		return form;
    },

    ajaxFileUpload: function(s) {
        // TODO introduce global settings, allowing the client to modify them for all requests, not only timeout		
        s = jQuery.extend({}, jQuery.ajaxSettings, s);
        var id = new Date().getTime();
		var form = jQuery.createUploadForm(id, s.fileElementId);
		var io = jQuery.createUploadIframe(id, s.secureuri);
		var frameId = 'jUploadFrame' + id;
		var formId = 'jUploadForm' + id;		
        // Watch for a new set of requests
        if ( s.global && ! jQuery.active++ ) {
			jQuery.event.trigger( "ajaxStart" );
		}
        var requestDone = false;
        // Create the request object
        var xml = {};
        if ( s.global ) jQuery.event.trigger("ajaxSend", [xml, s]);
        // Wait for a response to come back
        var uploadCallback = function(isTimeout) {			
			var io = document.getElementById(frameId);
            try {
            	var status;
				if(io.contentWindow) {
					xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;
                	xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;
					status = io.contentWindow.document.body.innerHTML;
				} else if(io.contentDocument) {
					xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;
                	xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;
                	status = io.contentDocument.document.body.innerHTML;
				}						
            } catch(e) {
				jQuery.handleError(s, xml, null, e);
			}
            if ( xml || isTimeout == "timeout") {				
                requestDone = true;
                try {
                    //status = isTimeout != "timeout" ? "success" : "error";
                    // Make sure that the request was successful or notmodified
                    if ( status == "FILE_UPLOAD_SUCCESS" ) {
                        // process the data (runs the xml through httpData regardless of callback)
                        var data = jQuery.uploadHttpData( xml, s.dataType );    
                        // If a local callback was specified, fire it and pass it the data
                        if ( s.success ) s.success( data, status );
                        // Fire the global callback
                        if( s.global )
                            jQuery.event.trigger( "ajaxSuccess", [xml, s] );
                    } else {
                        jQuery.handleError(s, xml, status);
                    }
                } catch(e) {
                    //status = "error";
                    jQuery.handleError(s, xml, status, e);
                }
                // The request was completed
                if( s.global ) jQuery.event.trigger( "ajaxComplete", [xml, s] );
                // Handle the global AJAX counter
                if ( s.global && ! --jQuery.active ) jQuery.event.trigger( "ajaxStop" );
                // Process result
                if ( s.complete ) s.complete(xml, status);
                jQuery(io).unbind();

                setTimeout( function() {
                	try {
						jQuery(io).remove();
						jQuery(form).remove();
					} catch(e) {
						jQuery.handleError(s, xml, null, e);
					}
				}, 100);
                xml = null;
            }
        };
        
        // Timeout checker
        if ( s.timeout > 0 ) {
            setTimeout(function() {
                // Check to see if the request is still happening
                if( !requestDone ) uploadCallback( "timeout" );
            }, s.timeout);
        }
        try {
           // var io = jQuery('#' + frameId);
        	var form = jQuery('#' + formId);
			jQuery(form).attr('action', 'fileUploader.action');
			jQuery(form).attr('method', 'POST');
			jQuery(form).attr('target', frameId);
			var pageref = '//de/ausgeblendet/handleuploadresult.jsp';
			jQuery(form).append('<input type="hidden" name="uploadResultCall" value="' + pageref + '" />');
			jQuery(form).append('<input type="hidden" name="uploadtype" value="' + s.uploadtype + '" />');

			if(form.encoding) {
                form.encoding = 'multipart/form-data';				
            } else {
                form.enctype = 'multipart/form-data';
            }
            jQuery(form).submit();
        } catch(e) {
            jQuery.handleError(s, xml, null, e);
        }
        if(window.attachEvent) {
            document.getElementById(frameId).attachEvent('onload', uploadCallback);
        } else {
            document.getElementById(frameId).addEventListener('load', uploadCallback, false);
        }
        return {abort: function () {}};
    },

    uploadHttpData: function( r, type ) {
        var data = !type;
        data = type == "xml" || data ? r.responseXML : r.responseText;
        // If the type is "script", eval it in global context
        if ( type == "script" ) jQuery.globalEval( data );
        // Get the JavaScript object, if JSON is used.
        if ( type == "json" ) eval( "data = " + data );
        // evaluate scripts within html
        if ( type == "html" ) jQuery("<div>").html(data).evalScripts();
			//alert(jQuery('param', data).each(function(){alert(jQuery(this).attr('value'));}));
        return data;
    }
});