chrome/browser/chromeos/power/ml/smart_dim/ml_agent.h

// Copyright 2020 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_CHROMEOS_POWER_ML_SMART_DIM_ML_AGENT_H_
#define CHROME_BROWSER_CHROMEOS_POWER_ML_SMART_DIM_ML_AGENT_H_

#include "base/cancelable_callback.h"
#include "base/no_destructor.h"
#include "chrome/browser/chromeos/power/ml/smart_dim/builtin_worker.h"
#include "chrome/browser/chromeos/power/ml/smart_dim/download_worker.h"
#include "chrome/browser/chromeos/power/ml/smart_dim/smart_dim_worker.h"
#include "chrome/browser/chromeos/power/ml/user_activity_event.pb.h"

namespace chromeos {
namespace power {
namespace ml {

using DimDecisionCallback =
    base::OnceCallback<void(UserActivityEvent::ModelPrediction)>;

// SmartDimMlAgent is responsible for preprocessing the features and requesting
// the inference from machine learning service.
// Usage:
//
//     SmartDimMlAgent::GetInstance()->RequestDimDecision(
//         features_, dim_decision_callback);
class SmartDimMlAgent {
 public:
  static SmartDimMlAgent* GetInstance();

  // Post a request to determine whether an upcoming dim should go ahead based
  // on input |features|. When a decision is arrived at, runs the callback. If
  // this method is called again before it calls the previous callback, the
  // previous callback will be canceled.
  void RequestDimDecision(const UserActivityEvent::Features& features,
                          DimDecisionCallback callback);
  void CancelPreviousRequest();

  // Called by CUS(component update service). When new version of the component
  // downloaded, CUS first uses IsDownloadWorkerReady to see if download worker
  // is ready. If it's not, CUS then uses OnComponentReady to update the
  // download metainfo, preprocessor and model.
  bool IsDownloadWorkerReady();
  void OnComponentReady(const ComponentFileContents& contents);

  // Called by ml_agent_unittest.cc to reset the builtin and download worker.
  void ResetForTesting();

 protected:
  SmartDimMlAgent();
  virtual ~SmartDimMlAgent();

 private:
  friend base::NoDestructor<SmartDimMlAgent>;

  // Return download_worker_ if it's ready, otherwise builtin_worker_.
  SmartDimWorker* GetWorker();

  BuiltinWorker builtin_worker_;
  DownloadWorker download_worker_;

  base::CancelableOnceCallback<void(UserActivityEvent::ModelPrediction)>
      dim_decision_callback_;

  SEQUENCE_CHECKER(sequence_checker_);

  DISALLOW_COPY_AND_ASSIGN(SmartDimMlAgent);
};

}  // namespace ml
}  // namespace power
}  // namespace chromeos

#endif  // CHROME_BROWSER_CHROMEOS_POWER_ML_SMART_DIM_ML_AGENT_H_