var ajax={};
ajax.xhr={}; // ajax.xhr ÆÐÅ°Áö Á¤ÀÇ

// Request Ŭ·¡½º »ý¼ºÀÚ. °´Ã¼ »ý¼º°ú µ¿½Ã¿¡ send() ÇÔ¼ö¸¦ È£Ãâ.
ajax.xhr.Request = function(url, params, callback, method) {
  this.url = url;
  this.params = params;
  this.callback = callback;
  this.method = method;
  this.send();
}

ajax.xhr.Request.prototype = {
  getXMLHttpRequest: function() {
    if (window.ActiveXObject) {
      try {
        return new ActiveXObject("Msxml2.XMLHTTP");
      } catch(e) {
        try {
          return new ActiveXObject("Microsoft.XMLHTTP");
        } catch(e1) { return null; }
      }
    } else if (window.XMLHttpRequest) {
      return new XMLHttpRequest();
    } else {
      return null;
    }
  },
  send: function() {
    this.req = this.getXMLHttpRequest();	// req ÇÁ·ÎÆÛƼ¿¡ XMLHttpRequest °´Ã¼¸¦ ÀúÀå

    var httpMethod = this.method ? this.method : 'GET';
    if (httpMethod != 'GET' && httpMethod != 'POST') {
      httpMethod = 'GET';
    }

    var httpParams = (this.params == null ||  this.params == '') ? null : this.params;
    var httpUrl = this.url;
    if (httpMethod=='GET' && httpParams != null) {
      httpUrl = httpUrl + "?" + httpParams;
    }

    this.req.open(httpMethod, httpUrl, true);
    this.req.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
    var request = this;
    this.req.onreadystatechange = function() {
      request.onStateChange.call(request);
    }
    this.req.send(httpMethod=='POST' ? httpParams : null);
  },
  onStateChange: function() {
    this.callback(this.req);
  }
}