*/*

Cross-Browser XMLHttpRequest v1.2
=================================

Emulate Gecko 'XMLHttpRequest()' functionality in IE and Opera. Opera requires
the Sun Java Runtime Environment <http://www.java.com/>.

by Andrew Gregory
http://www.scss.com.au/family/andrew/webdesign/xmlhttprequest/

This work is licensed under the Creative Commons Attribution License. To view a
copy of this license, visit http://creativecommons.org/licenses/by-sa/2.5/ or
send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California
94305, USA.

Attribution: Leave my name and web address in this script intact.

Not Supported in Opera
----------------------
* user/password authentication
* responseXML data member

Not Fully Supported in Opera
----------------------------
* async requests
* abort()
* getAllResponseHeaders(), getAllResponseHeader(header)

*/
// IE support
if (window.ActiveXObject && !window.XMLHttpRequest) {
window.XMLHttpRequest = function() {
  var msxmls = new Array(
    'Msxml2.XMLHTTP.5.0',
    'Msxml2.XMLHTTP.4.0',
    'Msxml2.XMLHTTP.3.0',
    'Msxml2.XMLHTTP',
    'Microsoft.XMLHTTP');
  for (var i = 0; i < msxmls.length; i++) {
    try {
      return new ActiveXObject(msxmls[i]);
    } catch (e) {
    }
  }
  return null;
};
}
// Gecko support
/* ;-) */
// Opera support
if (window.opera && !window.XMLHttpRequest) {
window.XMLHttpRequest = function() {
  this.readyState = 0; // 0=uninitialized,1=loading,2=loaded,3=interactive,4=complete
  this.status = 0; // HTTP status codes
  this.statusText = '';
  this._headers = [];
  this._aborted = false;
  this._async = true;
  this._defaultCharset = 'ISO-8859-1';
  this._getCharset = function() {
    var charset = _defaultCharset;
    var contentType = this.getResponseHeader('Content-type').toUpperCase();
    val = contentType.indexOf('CHARSET=');
    if (val != -1) {
      charset = contentType.substring(val);
    }
    val = charset.indexOf(';');
    if (val != -1) {
      charset = charset.substring(0, val);
    }
    val = charset.indexOf(',');
    if (val != -1) {
      charset = charset.substring(0, val);
    }
    return charset;
  };
  this.abort = function() {
    this._aborted = true;
  };
  this.getAllResponseHeaders = function() {
    return this.getAllResponseHeader('*');
  };
  this.getAllResponseHeader = function(header) {
    var ret = '';
    for (var i = 0; i < this._headers.length; i++) {
      if (header == '*' || this._headers[i].h == header) {
        ret += this._headers[i].h + ': ' + this._headers[i].v + '\n';
      }
    }
    return ret;
  };
  this.getResponseHeader = function(header) {
    var ret = getAllResponseHeader(header);
    var i = ret.indexOf('\n');
    if (i != -1) {
      ret = ret.substring(0, i);
    }
    return ret;
  };
  this.setRequestHeader = function(header, value) {
    this._headers[this._headers.length] = {h:header, v:value};
  };
  this.open = function(method, url, async, user, password) {
    this.method = method;
    this.url = url;
    this._async = true;
    this._aborted = false;
    this._headers = [];
    if (arguments.length >= 3) {
      this._async = async;
    }
    if (arguments.length > 3) {
      opera.postError('XMLHttpRequest.open() - user/password not supported');
    }
    this.readyState = 1;
    if (this.onreadystatechange) {
      this.onreadystatechange();
    }
  };
  this.send = function(data) {
    if (!navigator.javaEnabled()) {
      alert("XMLHttpRequest.send() - Java must be installed and enabled.");
      return;
    }
    if (this._async) {
      setTimeout(this._sendasync, 0, this, data);
      // this is not really asynchronous and won't execute until the current
      // execution context ends
    } else {
      this._sendsync(data);
    }
  }
  this._sendasync = function(req, data) {
    if (!req._aborted) {
      req._sendsync(data);
    }
  };
  this._sendsync = function(data) {
    this.readyState = 2;
    if (this.onreadystatechange) {
      this.onreadystatechange();
    }
    // open connection
    var url = new java.net.URL(new java.net.URL(window.location.href), this.url);
    var conn = url.openConnection();
    for (var i = 0; i < this._headers.length; i++) {
      conn.setRequestProperty(this._headers[i].h, this._headers[i].v);
    }
    this._headers = [];
    if (this.method == 'POST') {
      // POST data
      conn.setDoOutput(true);
      var wr = new java.io.OutputStreamWriter(conn.getOutputStream(), this._getCharset());
      wr.write(data);
      wr.flush();
      wr.close();
    }
    // read response headers
    // NOTE: the getHeaderField() methods always return nulls for me :(
    var gotContentEncoding = false;
    var gotContentLength = false;
    var gotContentType = false;
    var gotDate = false;
    var gotExpiration = false;
    var gotLastModified = false;
    for (var i = 0; ; i++) {
      var hdrName = conn.getHeaderFieldKey(i);
      var hdrValue = conn.getHeaderField(i);
      if (hdrName == null && hdrValue == null) {
        break;
      }
      if (hdrName != null) {
        this._headers[this._headers.length] = {h:hdrName, v:hdrValue};
        switch (hdrName.toLowerCase()) {
          case 'content-encoding': gotContentEncoding = true; break;
          case 'content-length'  : gotContentLength   = true; break;
          case 'content-type'    : gotContentType     = true; break;
          case 'date'            : gotDate            = true; break;
          case 'expires'         : gotExpiration      = true; break;
          case 'last-modified'   : gotLastModified    = true; break;
        }
      }
    }
    // try to fill in any missing header information
    var val;
    val = conn.getContentEncoding();
    if (val != null && !gotContentEncoding) this._headers[this._headers.length] = {h:'Content-encoding', v:val};
    val = conn.getContentLength();
    if (val != -1 && !gotContentLength) this._headers[this._headers.length] = {h:'Content-length', v:val};
    val = conn.getContentType();
    if (val != null && !gotContentType) this._headers[this._headers.length] = {h:'Content-type', v:val};
    val = conn.getDate();
    if (val != 0 && !gotDate) this._headers[this._headers.length] = {h:'Date', v:(new Date(val)).toUTCString()};
    val = conn.getExpiration();
    if (val != 0 && !gotExpiration) this._headers[this._headers.length] = {h:'Expires', v:(new Date(val)).toUTCString()};
    val = conn.getLastModified();
    if (val != 0 && !gotLastModified) this._headers[this._headers.length] = {h:'Last-modified', v:(new Date(val)).toUTCString()};
    // read response data
    var reqdata = '';
    var stream = conn.getInputStream();
    if (stream) {
      var reader = new java.io.BufferedReader(new java.io.InputStreamReader(stream, this._getCharset()));
      var line;
      while ((line = reader.readLine()) != null) {
        if (this.readyState == 2) {
          this.readyState = 3;
          if (this.onreadystatechange) {
            this.onreadystatechange();
          }
        }
        reqdata += line + '\n';
      }
      reader.close();
      this.status = 200;
      this.statusText = 'OK';
      this.responseText = reqdata;
      this.readyState = 4;
      if (this.onreadystatechange) {
        this.onreadystatechange();
      }
      if (this.onload) {
        this.onload();
      }
    } else {
      // error
      this.status = 404;
      this.statusText = 'Not Found';
      this.responseText = '';
      this.readyState = 4;
      if (this.onreadystatechange) {
        this.onreadystatechange();
      }
      if (this.onerror) {
        this.onerror();
      }
    }
  };
};
}
// ActiveXObject emulation
if (!window.ActiveXObject && window.XMLHttpRequest) {
window.ActiveXObject = function(type) {
  switch (type.toLowerCase()) {
    case 'microsoft.xmlhttp':
    case 'msxml2.xmlhttp':
    case 'msxml2.xmlhttp.3.0':
    case 'msxml2.xmlhttp.4.0':
    case 'msxml2.xmlhttp.5.0':
      return new XMLHttpRequest();
  }
  return null;
};
}*