jQuery.extend({


    createUploadIframe: function(id, uri) {
			//create frame
            var frameId = 'jUploadFrame' + id;
            var iframeHtml = '<iframe id="' + frameId + '" name="' + frameId + '" style="position:absolute; top:-9999px; left:-9999px"';
			if(window.ActiveXObject) {
                if(typeof uri== 'boolean') {
					iframeHtml += ' src="' + 'javascript:false' + '"';

                }
                else if(typeof uri== 'string') {
					iframeHtml += ' src="' + uri + '"';

                }
			}
			iframeHtml += ' />';
			jQuery(iframeHtml).appendTo(document.body);

            return jQuery('#' + frameId).get(0);
    },
    
    createUploadForm: function(id, fileElementId, data) {
		//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>');
		if(data) {
			for(var i in data) {
				jQuery('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(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
    	//alert('===ajaxFileUpload3===');
        s = jQuery.extend({}, jQuery.ajaxSettings, s);
        var id = new Date().getTime();
		var form = jQuery.createUploadForm(id, s.fileElementId, (typeof(s.data)=='undefined'?false:s.data));
		var frame = 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 = frame;
            try {
				if(io.contentWindow) {
					//alert('===1===');
					 xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerText:null;
                	 xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;

				} else if(io.contentDocument) {
					//alert('===2===');
					xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerText:null;
                	xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;
				}
            } catch(e) {
            	//alert('===E1==='+e);
				jQuery.handleError(s, xml, null, e);
			}
            if ( xml || isTimeout == "timeout") {
                requestDone = true;
                var status;
                try {
                    status = isTimeout != "timeout" ? "success" : "error";
                    // Make sure that the request was successful or notmodified
                    //alert('===2==='+isTimeout+' '+status);
                    if ( status != "error" ) {
                        // process the data (runs the xml through httpData regardless of callback)
                    	//alert('===3===');
                        var data = jQuery.uploadHttpData( xml, s.dataType );
                        //alert('===4===');
                        // If a local callback was specified, fire it and pass it the data
                        if ( s.success ){
                        	//alert('===5===');
                            s.success( data, status );
                            //alert('===6===');
                        }
                        // Fire the global callback
                        if( s.global ){
                        	//alert('===7===');
                            jQuery.event.trigger( "ajaxSuccess", [xml, s] );
                        }
                    } else
                        jQuery.handleError(s, xml, status);
                } catch(e) {
                	//alert('===E2==='+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 form = jQuery('#' + formId);
			jQuery(form).attr('action', s.url);
			jQuery(form).attr('method', 'POST');
			jQuery(form).attr('target', frameId);
            if(form.encoding) {
				jQuery(form).attr('encoding', 'multipart/form-data');
            } else {
				jQuery(form).attr('enctype', 'multipart/form-data');
            }
            

            if ( frame.attachEvent )
            	frame.attachEvent( 'onload', uploadCallback );
            else if ( frame.addEventListener ) 
            	frame.addEventListener( 'load', uploadCallback, false );
            
            jQuery( form ).submit();
            
        } catch(e) {
            jQuery.handleError(s, xml, null, e);
        }
        
		jQuery('#' + frameId).load(uploadCallback);
        
		return {abort: function () {}};

    },

    uploadHttpData: function( r, type ) {
    	//alert('===uploadHttpData 1==='+type);
        var data = !type;
        //alert('===uploadHttpData 2===');
        data = type == "xml" || data ? r.responseXML : r.responseText;
        // If the type is "script", eval it in global context
        if ( type == "script" ){
        	//alert('===uploadHttpData 3===');
            jQuery.globalEval( data );
        }
        // Get the JavaScript object, if JSON is used.
        if ( type == "json" ){
        	//alert('===uploadHttpData 4===');
            eval( "data = " + data );
        }
        // evaluate scripts within html
        if ( type == "html" ){
        	//alert('===uploadHttpData 5===');
            jQuery("<div>").html(data).evalScripts();
        }
        return data;
    },
    
    handleError: function( s, xhr, status, e ) {
    	// If a local callback was specified, fire it
		if ( s.error ) {
			s.error.call( s.context || s, xhr, status, e );
		}

		// Fire the global callback
		if ( s.global ) {
			(s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );
		}
	}
});