/** * XMLHttpRequest Wrapper * @category    HTML * @package 	AJAX * @author      Joshua Eichorn <josh@bluga.net> * @copyright   2005 Joshua Eichorn * @license     http://www.opensource.org/licenses/lgpl-license.php  LGPL */function HTML_AJAX_HttpClient() { }HTML_AJAX_HttpClient.prototype = {	// request object	request: null,	// timeout id	_timeoutId: null,	callbackComplete: true,	// has this request been aborted	aborted: false,		// method to initialize an xmlhttpclient	init:function() 	{		try {			// Mozilla / Safari			//this.xmlhttp = new HTML_AJAX_IframeXHR(); //uncomment these two lines to test iframe			//return;			this.xmlhttp = new XMLHttpRequest();		} catch (e) {			// IE			var XMLHTTP_IDS = new Array(			'MSXML2.XMLHTTP.5.0',			'MSXML2.XMLHTTP.4.0',			'MSXML2.XMLHTTP.3.0',			'MSXML2.XMLHTTP',			'Microsoft.XMLHTTP' );			var success = false;			for (var i=0;i < XMLHTTP_IDS.length && !success; i++) {				try {					this.xmlhttp = new ActiveXObject(XMLHTTP_IDS[i]);					success = true;				} catch (e) {}			}			if (!success) {				try{					this.xmlhttp = new HTML_AJAX_IframeXHR();					this.request.iframe = true;				} catch(e) {					throw new Error('Unable to create XMLHttpRequest.');				}			}		}	},	// check if there is a call in progress	callInProgress: function() 	{		switch ( this.xmlhttp.readyState ) {			case 1:			case 2:			case 3:				return true;			break;			default:				return false;			break;		}	},	// make the request defined in the request object	makeRequest: function() 	{		if (!this.xmlhttp) {			this.init();		}		try {			if (this.request.Open) {				this.request.Open();			}			else if (HTML_AJAX.Open) {				HTML_AJAX.Open(this.request);			}			if (this.request.multipart) {				if (document.all) {					this.iframe = true;				} else {					this.xmlhttp.multipart = true;				}			}				// set onreadystatechange here since it will be reset after a completed call in Mozilla			var self = this;			this.xmlhttp.open(this.request.requestType,this.request.completeUrl(),this.request.isAsync);			if (this.request.customHeaders) {				for (i in this.request.customHeaders) {					this.xmlhttp.setRequestHeader(i, this.request.customHeaders[i]);				}			}			if (this.request.customHeaders && !this.request.customHeaders['Content-Type']) {				var content = this.request.getContentType();				//opera is stupid for anything but plain text or xml!!				if(window.opera && content != 'application/xml')				{					this.xmlhttp.setRequestHeader('Content-Type','text/plain; charset=utf-8');					this.xmlhttp.setRequestHeader('x-Content-Type', content + '; charset=utf-8');				}				else				{					this.xmlhttp.setRequestHeader('Content-Type', content +  '; charset=utf-8');				}			}			if (this.request.isAsync) {				if (this.request.callback) {					this.callbackComplete = false;				}				this.xmlhttp.onreadystatechange = function() { self._readyStateChangeCallback(); }			} else {				this.xmlhttp.onreadystatechange = function() {}			}			var payload = this.request.getSerializedPayload();			if (payload) {				this.xmlhttp.setRequestHeader('Content-Length', payload.length);			}			this.xmlhttp.send(payload);			if (!this.request.isAsync) {				if ( this.xmlhttp.status == 200 ) {					HTML_AJAX.requestComplete(this.request);					if (this.request.Load) {						this.request.Load();					} else if (HTML_AJAX.Load) {						HTML_AJAX.Load(this.request);					}											return this._decodeResponse();				} else {					var e = new Error('['+this.xmlhttp.status +'] '+this.xmlhttp.statusText);					e.headers = this.xmlhttp.getAllResponseHeaders();					this._handleError(e);				}			}			else {				// setup timeout				var self = this;				this._timeoutId = window.setTimeout(function() { self.abort(true); },this.request.timeout);			}		} catch (e) {			this._handleError(e);		}	},		// abort an inprogress request	abort: function (automatic) 	{		if (this.callInProgress()) {			this.aborted = true;			this.xmlhttp.abort();			if (automatic) {				HTML_AJAX.requestComplete(this.request);				this._handleError(new Error('Request Timed Out: time out was '+this.request.timeout+'ms'));			}		}	},	// internal method used to handle ready state changes	_readyStateChangeCallback:function() 	{		try {			switch(this.xmlhttp.readyState) {				// XMLHTTPRequest.open() has just been called				case 1:					break;				// XMLHTTPRequest.send() has just been called				case 2:					if (this.request.Send) {						this.request.Send();					} else if (HTML_AJAX.Send) {						HTML_AJAX.Send(this.request);					}					break;				// Fetching response from server in progress				case 3:					if (this.request.Progress) {						this.request.Progress();					} else if (HTML_AJAX.Progress ) {						HTML_AJAX.Progress(this.request);					}				break;				// Download complete				case 4:					window.clearTimeout(this._timeoutId);					if (this.aborted) {						if (this.request.Load) {							this.request.Load();						} else if (HTML_AJAX.Load) {							HTML_AJAX.Load(this.request);						}					}					else if (this.xmlhttp.status == 200) {						if (this.request.Load) {							this.request.Load();						} else if (HTML_AJAX.Load ) {							HTML_AJAX.Load(this.request);						}						var response = this._decodeResponse();						if (this.request.callback) {							this.request.callback(response);							this.callbackComplete = true;						}					}					else {						var e = new Error('HTTP Error Making Request: ['+this.xmlhttp.status+'] '+this.xmlhttp.statusText);						this._handleError(e);					}					HTML_AJAX.requestComplete(this.request);				break;			}		} catch (e) {				this._handleError(e);		}	},	// decode response as needed	_decodeResponse: function() {		//try for x-Content-Type first		var content = null;		try {			content = this.xmlhttp.getResponseHeader('X-Content-Type');		} catch(e) {}		if(!content || content == null)		{			content = this.xmlhttp.getResponseHeader('Content-Type');		}		//strip anything after ;		if(content.indexOf(';') != -1)		{			content = content.substring(0, content.indexOf(';'));		}		// hook for xml, it doesn't need to be unserialized		if(content == 'application/xml')		{			return this.xmlhttp.responseXML;		}		var unserializer = HTML_AJAX.serializerForEncoding(content);		//alert(this.xmlhttp.getAllResponseHeaders()); // some sort of debug hook is needed here		return unserializer.unserialize(this.xmlhttp.responseText);	},	// handle sending an error where it needs to go	_handleError: function(e) 	{		HTML_AJAX.requestComplete(this.request,e);		if (this.request.onError) {			this.request.onError(e);		} else if (HTML_AJAX.onError) {			HTML_AJAX.onError(e,this.request);		}		else {			throw e;		}	}}