// JavaScript Document

/* AJAX implementation */

HTTPRequest = function(){};
with({$: HTTPRequest.prototype}){
    $.isSupported = function(){
        return !!this.getConnection();
    };
    $.events = ["start", "open", "send", "load", "end"];
    $.filter = encodeURIComponent;
    $.getConnection = function(){
        var i, o = [function(){return new ActiveXObject("Msxml2.XMLHTTP");},
        function(){return new ActiveXObject("Microsoft.XMLHTTP");},
        function(){return new XMLHttpRequest;}];
        for(i = o.length; i--;) try{return o[i]();} catch(e){}
        return null;
    };
    $.formatParams = function(params){
        var i, r = [];
        for(i in params) r[r.length] = i + "=" + (this.filter ? this.filter(params[i]) : params[i]);
        return r.join("&");
    };
    $.get = function(url, params, handler, waitResponse){
        return this.request("GET", url + (url.indexOf("?") + 1 ? "&" : "?") + this.formatParams(params), null, handler, null, waitResponse);
    };
    $.post = function(url, params, handler, waitResponse){
        return this.request("POST", url, params /*= this.formatParams(params)*/, handler, {
            "Connection": "close",
            "Content-Length": params.length,
            "Method": "POST " + url + " HTTP/1.1",
            "Content-Type": "application/x-www-form-urlencoded; charset=utf-8"
        }, waitResponse);
    };
    $.request = function(method, url, params, handler, headers, waitResponse){
        var i, o = this.getConnection(), f = handler instanceof Function;
        try{
            o.open(method, url, !waitResponse);
            waitResponse || (o.onreadystatechange = function(){
                var s = $.events[o.readyState];
                f ? handler(o) : s in handler && handler[s](o);
            });
            o.setRequestHeader("HTTP_USER_AGENT", "XMLHttpRequest");
            for(i in headers)
                o.setRequestHeader(i, headers[i]);
            o.send(params);
            waitResponse && (f ? handler(o) : handler["end"] && handler["end"](o));
            return true;
        }
        catch(e){
            return false;
        }
    };
}