/* 
	Library: Gainsborough - web client framework
	Component: AJAX object v2.0
	
	Hextra Digital 
	http://www.hextra-digital.com
*/

/*
	ajaxobject2 basic implementation - used in ajax requests
	can be expanded by using ajaxobject2.prototype
*/

var eAjaxModes = { Get: 0, Post: 1 };

function ajaxobject2() {}

ajaxobject2.prototype = {
	eCodes: { Ok: 0, NoXHR: 1, Exception: 2, Error: 3, NoStatus: 4, Connecting: 5, Processing: 6, Starting: 7 },
	create: function( _this, _callback, _mode, _url, _parameters ) {
		this.thisPtr		= _this;
		this.mode			= _mode;
		this.url			= _url;
		this.callback		= _callback;
		this.parameters		= _parameters;
		this.retry			= 0;
		this.timeout		= null;
		this.createXHR();				
	},
	enableAutoRetry: function( _interval ) {
		this.retry = _interval;
	},
	checkRetry: function() {
		this.clearRetry();
		if( this.retry > 0 ){
			var thisPtr = this;
			this.timeout = setTimeout( function(){ thisPtr.request(); }, this.retry );
		}	
	},
	destroy: function() {
		clearRetry();
		this.http_request = null;
		return null;
	},
	clearRetry: function() {
		if( this.timeout ) {
			clearTimeout( this.timeout );
			this.timeout = null;
		}
	},
	createXHR: function() {

		if( window.XMLHttpRequest ) { // Mozilla, Safari,...
			this.http_request = new XMLHttpRequest();
			if( this.http_request ) {
				if( this.http_request.overrideMimeType ) {
					this.http_request.overrideMimeType( 'text/xml' );
				}
			}
		} else if( window.ActiveXObject ) { // MSIE 
			try {
				this.http_request = new ActiveXObject( 'Msxml2.XMLHTTP' );
			} catch( e ) {
				try {
					this.http_request = new ActiveXObject( 'Microsoft.XMLHTTP' );
				} 
				catch( e ) {
					this.notify( this.eCodes.Exception, e.description );
				}
			}
		}

		if( !this.http_request ) {
			this.notify( this.eCodes.NoXHR, '' );
			return false;
		}

		if( this.callback ) {
			var thisObj = this;
			this.http_request.onreadystatechange = function() { thisObj.process(); };
		}		
	},
	request: function() {

		this.clearRetry();
		this.notify( this.eCodes.Starting, '' );

		switch( this.mode ) {
		case eAjaxModes.Post: { // asynchronous HTTP POST			
			this.notify( this.eCodes.Connecting, '' );
			this.http_request.open( 'POST', this.url, true ); 
			this.http_request.setRequestHeader( 'Content-type', 'application/x-www-form-urlencoded' );
			this.http_request.setRequestHeader( 'Content-length', this.parameters.length );
			this.http_request.setRequestHeader( 'Connection', 'close' );
			this.http_request.send( this.parameters );
			break;
		} 
		case eAjaxModes.Get: { // asynchronous HTTP GET
			this.notify( this.eCodes.Connecting, '' );
			this.http_request.open( 'GET', this.url, true );
			this.http_request.send( null );
			break;
		}
		default: {			
		}
		}
	
	},
	process: function() {
	
		this.notify( this.eCodes.Processing, '' );
		if( this.http_request )	{
			if( this.http_request.readyState == 4 ) { // once is completed		
				try {
					if( this.http_request.status ) {
						if( this.http_request.status == 200 || this.http_request.status == 0 ) { // OK
							if( this.callback ) {
								try {
									this.notify( this.eCodes.Ok, '' );
									this.callback( this );
								} catch( e ) {
									this.notify( this.eCodes.Exception, e.description );
								}
							} else { 
								return this;
							}
						} else { // 404, 500, etc.
							this.notify( this.eCodes.Error, '' ); 
						}
					} else this.notify( this.eCodes.NoStatus, '' );
				} catch( e ) {
					this.notify( this.eCodes.Exception, e.description );
				}
				//this.destroy();
			}
		} else {
			this.notify( eCodes.Exception, e.description );
		}
		
	},
	notify: function( _code, _text ) {		
		switch( _code ){
		case this.eCodes.Exception:{ this.checkRetry(); break; }
		case this.eCodes.Error:{ this.checkRetry(); break; }
		}
	}
};