/*****************************
**   AJAX
******************************/

/*
	url - откуда загружаем
	ajaxCallBackFunction - что вызываем по завершении загрузки
	callObject - методом какого объекта является ajaxCallBackFunction (если это метод, а не глобальная фунция)
	params - параметры в виде объекта или массива
	ajaxCallBackErrorFunction - необязательная функция, обрабатывающая ошибки соединения
*/
function ajaxLoad(url, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction) {
	// branch for native XMLHttpRequest object
	if (window.XMLHttpRequest) {
		var ajaxObject = new XMLHttpRequest();
		ajaxObject.onreadystatechange = function(){
			ajaxLoadHandler(ajaxObject, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction);
		}
		ajaxObject.open("GET", url, true);
		ajaxObject.send(null);
	// branch for IE/Windows ActiveX version
	} else if (window.ActiveXObject) {
		var ajaxObject = new ActiveXObject("Microsoft.XMLHTTP");
		if (ajaxObject) {
			ajaxObject.onreadystatechange = function(){
				ajaxLoadHandler(ajaxObject, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction);
			}
			ajaxObject.open("GET", url, true);
			ajaxObject.send();
		}
	}
}

function ajaxLoadHandler(ajaxObject, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction){
	// only if req shows "complete"
	if (ajaxObject.readyState == 4) {
		// only if "OK"
		if (ajaxObject.status == 200) {
			// ...processing statements go here...
			ajaxCallBackFunction.call(callObject, ajaxObject, params);
		} else {
			if(ajaxCallBackErrorFunction){
				ajaxCallBackErrorFunction.call(callObject, ajaxObject, params);	
			} else {
				alert("There was a problem retrieving the XML data:\n" + ajaxObject.statusText);
			}
		}
	}
}


function ajaxLoadPost(url, data, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction) {
	var ajaxObject = null;
	
	if (window.XMLHttpRequest) { // branch for native XMLHttpRequest object
		ajaxObject = new XMLHttpRequest();
	} else if (window.ActiveXObject) { // branch for IE/Windows ActiveX version
		var ajaxObject = new ActiveXObject("Microsoft.XMLHTTP");
	}
	if(ajaxObject){
		ajaxObject.onreadystatechange = function(){
			ajaxLoadHandler(ajaxObject, ajaxCallBackFunction, callObject, params, ajaxCallBackErrorFunction);
		}
		ajaxObject.open("POST", url, true);
		ajaxObject.setRequestHeader("Content-type", "application/x-www-form-urlencoded; charset=windows-1251");
		ajaxObject.setRequestHeader("Content-length", data.length);
		ajaxObject.setRequestHeader("Connection", "close");
		ajaxObject.send(data);	
	}
}



/* Class inheritance*/
Function.prototype.inheritFrom = function(BaseClass) { // thanks to Kevin Lindsey for this idea
  var Inheritance = function() {};
  Inheritance.prototype = BaseClass.prototype;

  this.prototype = new Inheritance();
  this.prototype.constructor = this;
  this.baseConstructor = BaseClass;
  this.superClass = BaseClass.prototype;
}


if(!Function.prototype.call) { // emulating 'call' function for browsers not supporting it (IE5)
	Function.prototype.call = function() {
		var oObject = arguments[0];
		var aArguments = [];
		var oResult;       
		oObject.fFunction = this;
		for (var i = 1; i < arguments.length; i++) {
			aArguments[aArguments.length] = 'arguments[' + i + ']';         
		}
		eval('oResult = oObject.fFunction(' + aArguments.join(',') + ')');
		oObject.fFunction = null;
		return oResult;
	}
}