var count_refresh_img = 0;
/*function http_request_obj(){
	var http_request;
	if (window.XMLHttpRequest){
		http_request = new XMLHttpRequest();
	 	if (http_request.overrideMimeType){ http_request.overrideMimeType('text/xml'); }
	}
	else if (window.ActiveXObject){
		try{ http_request = new ActiveXObject("Msxml2.XMLHTTP"); }
	    catch (e){
	    	try { http_request = new ActiveXObject("Microsoft.XMLHTTP"); }
	        catch (e){}
	    }
	}
	if (!http_request){
		alert('Îøèáêà :(');
	 	return false;
	}
	else{ return http_request; }
}*/
var http_request_obj =  window.XMLHttpRequest && (window.location.protocol !== "file:" || !window.ActiveXObject) ?
            function() { 
                return new window.XMLHttpRequest(); 
            } :
            function() {
                try {
                    return new window.ActiveXObject("Microsoft.XMLHTTP");
                } catch(e) {}
            };
function refresh_captcha(obj, key){
    var http_request = http_request_obj();
	http_request.onreadystatechange = function(){ refresh_captcha_result(http_request, obj, key); }
	http_request.open('GET', 'http://' + window.location.host + '/captcha/refresh/' + key + '/?r=' + count_refresh_img, 'true');
	http_request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	http_request.send(null);
}
function refresh_captcha_result(http_request, obj, key){
    if (http_request.readyState == 4 && http_request.status == 200){
        var parent_element = obj.parentNode;
        var image_list = parent_element.getElementsByTagName('img');
        for(var i=0; i<image_list.length; i++){
            if(!image_list[i]) continue;
            else{
                if(image_list[i].src.indexOf(key)){ 
                    image_list[i].src = 'http://'+ window.location.host + '/captcha/image/' + key + '/?r=' + count_refresh_img;
                    count_refresh_img++;
                    break;
                }
            }
        }
    }
}