class ChromeDebugger extends ChromeApi {
 static final JsObject _debugger = chrome['debugger'];

 ChromeDebugger._();

 bool get available => _debugger != null;

 /**
  * Attaches debugger to the given target.
  * 
  * [target] Debugging target to which you want to attach.
  * 
  * [requiredVersion] Required debugging protocol version ("0.1"). One can only
  * attach to the debuggee with matching major version and greater or equal
  * minor version. List of the protocol versions can be obtained
  * [here](http://code.google.com/chrome/devtools/docs/remote-debugging.html).
  */
 Future attach(Debuggee target, String requiredVersion) {
   if (_debugger == null) _throwNotAvailable();

   var completer = new ChromeCompleter.noArgs();
   _debugger.callMethod('attach', [jsify(target), requiredVersion, completer.callback]);
   return completer.future;
 }

 /**
  * Detaches debugger from the given target.
  * 
  * [target] Debugging target from which you want to detach.
  */
 Future detach(Debuggee target) {
   if (_debugger == null) _throwNotAvailable();

   var completer = new ChromeCompleter.noArgs();
   _debugger.callMethod('detach', [jsify(target), completer.callback]);
   return completer.future;
 }

 /**
  * Sends given command to the debugging target.
  * 
  * [target] Debugging target to which you want to send the command.
  * 
  * [method] Method name. Should be one of the methods defined by the [remote
  * debugging
  * protocol](http://code.google.com/chrome/devtools/docs/remote-debugging.html).
  * 
  * [commandParams] JSON object with request parameters. This object must
  * conform to the remote debugging params scheme for given method.
  * 
  * Returns:
  * JSON object with the response. Structure of the response varies depending
  * on the method and is defined by the remote debugging protocol.
  */
 Future<Map<String, dynamic>> sendCommand(Debuggee target, String method, [Map<String, dynamic> commandParams]) {
   if (_debugger == null) _throwNotAvailable();

   var completer = new ChromeCompleter<Map<String, dynamic>>.oneArg(mapify);
   _debugger.callMethod('sendCommand', [jsify(target), method, jsify(commandParams), completer.callback]);
   return completer.future;
 }

 /**
  * Returns the list of available debug targets.
  * 
  * Returns:
  * Array of TargetInfo objects corresponding to the available debug targets.
  */
 Future<List<TargetInfo>> getTargets() {
   if (_debugger == null) _throwNotAvailable();

   var completer = new ChromeCompleter<List<TargetInfo>>.oneArg((e) => listify(e, _createTargetInfo));
   _debugger.callMethod('getTargets', [completer.callback]);
   return completer.future;
 }

 /**
  * Fired whenever debugging target issues instrumentation event.
  */
 Stream<OnEventEvent> get onEvent => _onEvent.stream;

 final ChromeStreamController<OnEventEvent> _onEvent =
     new ChromeStreamController<OnEventEvent>.threeArgs(_debugger, 'onEvent', _createOnEventEvent);

 /**
  * Fired when browser terminates debugging session for the tab. This happens
  * when either the tab is being closed or Chrome DevTools is being invoked for
  * the attached tab.
  */
 Stream<OnDetachEvent> get onDetach => _onDetach.stream;

 final ChromeStreamController<OnDetachEvent> _onDetach =
     new ChromeStreamController<OnDetachEvent>.twoArgs(_debugger, 'onDetach', _createOnDetachEvent);

 void _throwNotAvailable() {
   throw new UnsupportedError("'chrome.debugger' is not available");
 }
}