/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef ThreadResponsiveness_h

#define ThreadResponsiveness_h

#include "nsISupports.h"

#include "mozilla/Maybe.h"

#include "mozilla/RefPtr.h"

#include "mozilla/TimeStamp.h"

class CheckResponsivenessTask;

class nsIEventTarget;

// This class should only be used for the main thread.

class ThreadResponsiveness {

public:

  explicit ThreadResponsiveness(nsIEventTarget* aThread, bool aIsMainThread);

  ~ThreadResponsiveness();

  void Update();

  // The number of milliseconds that elapsed since the last

  // CheckResponsivenessTask was processed.

  double GetUnresponsiveDuration(double aStartToNow_ms) const {

    return aStartToNow_ms - *mStartToPrevTracer_ms;

  }

  bool HasData() const {

    return mStartToPrevTracer_ms.isSome();

  }

private:

  RefPtr<CheckResponsivenessTask> mActiveTracerEvent;

  // The time at which the last CheckResponsivenessTask was processed, in

  // milliseconds since process start (i.e. what you get from profiler_time()).

  mozilla::Maybe<double> mStartToPrevTracer_ms;

};

#endif