var ajax = new Object();

ajax.has_xml_http = false;
ajax.xml_http     = null;
ajax.result_cache = new Object();

/****************************************************************************************/
ajax.getXmlHttpObject = function()
{
  var obj = null;
  
  //get xml object for IE
  try {
    obj = new ActiveXObject("Msxml2.XMLHTTP");
  }
  catch(e) {
    try {
      obj = new ActiveXObject("Microsoft.XMLHTTP");
    }
    catch(et) {
      obj = null;
    }
  }
  
  //get XML object for mozilla
  if (!obj && typeof XMLHttpRequest != "undefined")
  {
    obj = new XMLHttpRequest();
  }
  
  return obj;
};
ajax.has_xml_http = ajax.getXmlHttpObject() ? true : false;

/****************************************************************************************/
ajax.cacheResults = function(key, page, value)
{
  ajax.result_cache[key] = value;
//  ajax.result_cache[key + '-' + page] = value;
};

/****************************************************************************************/
ajax.getFromCache = function(key)
{
  return ajax.result_cache[key];
};

/****************************************************************************************/
ajax.throwError = function(s)
{
  alert(s);
};

/****************************************************************************************/
ajax.sendRequest = function(url, method, do_eval)
{
  if (ajax.xml_http && ajax.xml_http.readyState!=0)
  {
    ajax.xml_http.abort()
  }
  ajax.xml_http = ajax.getXmlHttpObject();
  
  if (ajax.xml_http)
  {
    ajax.xml_http.open(method, url, true);
    ajax.xml_http.onreadystatechange = function()
    {
      if (ajax.xml_http.readyState==4 && ajax.xml_http.responseText)
      {
        if (do_eval)
        {
          eval(ajax.xml_http.responseText);
        }
        else
        {
          document.write(ajax.xml_http.responseText);
        }
      }
    };
    ajax.xml_http.send(null);
  }
};

var Url = {

    // public method for url encoding
    encode : function (string) {
        return escape(this._utf8_encode(string));
    },

    // public method for url decoding
    decode : function (string) {
        return this._utf8_decode(unescape(string));
    },

    // private method for UTF-8 encoding
    _utf8_encode : function (string) {
        string = string.replace(/\r\n/g,"\n");
        var utftext = "";

        for (var n = 0; n < string.length; n++) {

            var c = string.charCodeAt(n);

            if (c < 128) {
                utftext += String.fromCharCode(c);
            }
            else if((c > 127) && (c < 2048)) {
                utftext += String.fromCharCode((c >> 6) | 192);
                utftext += String.fromCharCode((c & 63) | 128);
            }
            else {
                utftext += String.fromCharCode((c >> 12) | 224);
                utftext += String.fromCharCode(((c >> 6) & 63) | 128);
                utftext += String.fromCharCode((c & 63) | 128);
            }

        }

        return utftext;
    },

    // private method for UTF-8 decoding
    _utf8_decode : function (utftext) {
        var string = "";
        var i = 0;
        var c = c1 = c2 = 0;

        while ( i < utftext.length ) {

            c = utftext.charCodeAt(i);

            if (c < 128) {
                string += String.fromCharCode(c);
                i++;
            }
            else if((c > 191) && (c < 224)) {
                c2 = utftext.charCodeAt(i+1);
                string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
                i += 2;
            }
            else {
                c2 = utftext.charCodeAt(i+1);
                c3 = utftext.charCodeAt(i+2);
                string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
                i += 3;
            }

        }

        return string;
    }

}