pausable_state.h - mozsearch

Enable keyboard shortcuts

/*

 *  Copyright (c) 2023 The WebRTC project authors. All Rights Reserved.

 *  Use of this source code is governed by a BSD-style license

 *  that can be found in the LICENSE file in the root of the source

 *  tree. An additional intellectual property rights grant can be found

 *  in the file PATENTS.  All contributing project authors may

 *  be found in the AUTHORS file in the root of the source tree.

*/

#ifndef TEST_PC_E2E_ANALYZER_VIDEO_DVQA_PAUSABLE_STATE_H_

#define TEST_PC_E2E_ANALYZER_VIDEO_DVQA_PAUSABLE_STATE_H_

#include <cstdint>

#include <vector>

#include "api/units/time_delta.h"

#include "api/units/timestamp.h"

#include "system_wrappers/include/clock.h"

namespace webrtc {

// Provides ability to pause and resume and tell at any point was state paused

// or active.

class PausableState {

 public:

  // Creates a state as active.

  explicit PausableState(Clock* clock) : clock_(clock) {}

  PausableState(const PausableState&) = delete;

  PausableState& operator=(const PausableState&) = delete;

  PausableState(PausableState&&) = default;

  PausableState& operator=(PausableState&&) = default;

  // Pauses current state. States MUST be active.

//

  // Complexity: O(1)

  void Pause();

  // Activates current state. State MUST be paused.

//

  // Complexity: O(1)

  void Resume();

  // Returns is state is paused right now.

//

  // Complexity: O(1)

  bool IsPaused() const;

  // Returns if last event before `time` was "pause".

//

  // Complexity: O(log(n))

  bool WasPausedAt(Timestamp time) const;

  // Returns if next event after `time` was "resume".

//

  // Complexity: O(log(n))

  bool WasResumedAfter(Timestamp time) const;

  // Returns time of last event or plus infinity if no events happened.

//

  // Complexity O(1)

  Timestamp GetLastEventTime() const;

  // Returns sum of durations during which state was active starting from

  // time `time`.

//

  // Complexity O(n)

  TimeDelta GetActiveDurationFrom(Timestamp time) const;

 private:

  struct Event {

    Timestamp time;

    bool is_paused;

};

  // Returns position in `events_` which has time:

  // 1. Most right of the equals

  // 2. The biggest which is smaller

  // 3. -1 otherwise (first time is bigger than `time`)

  int64_t GetPos(Timestamp time) const;

  Clock* clock_;

  std::vector<Event> events_;

};

}  // namespace webrtc

#endif  // TEST_PC_E2E_ANALYZER_VIDEO_DVQA_PAUSABLE_STATE_H_