chromium/chromeos/ash/components/report/device_metrics/churn/observation_impl.h

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROMEOS_ASH_COMPONENTS_REPORT_DEVICE_METRICS_CHURN_OBSERVATION_IMPL_H_
#define CHROMEOS_ASH_COMPONENTS_REPORT_DEVICE_METRICS_CHURN_OBSERVATION_IMPL_H_

#include "base/component_export.h"
#include "base/memory/weak_ptr.h"
#include "chromeos/ash/components/report/device_metrics/use_case/use_case.h"

namespace network {
class SimpleURLLoader;
}  // namespace network

namespace ash::report::device_metrics {

class ActiveStatus;

class COMPONENT_EXPORT(CHROMEOS_ASH_COMPONENTS_REPORT) ObservationImpl
    : public UseCase {
 public:
  explicit ObservationImpl(UseCaseParameters* params);
  ObservationImpl(const ObservationImpl&) = delete;
  ObservationImpl& operator=(const ObservationImpl&) = delete;
  ~ObservationImpl() override;

  // UseCase:
  void Run(base::OnceCallback<void()> callback) override;

  // Used by ReportController to destruct pending callbacks appropriately.
  base::WeakPtr<ObservationImpl> GetWeakPtr();

  // Testing
  std::optional<FresnelImportDataRequest> GenerateImportRequestBodyForTesting();

 protected:
  // UseCase:
  void CheckMembershipOprf() override;
  void OnCheckMembershipOprfComplete(
      std::unique_ptr<std::string> response_body) override;
  void CheckMembershipQuery(
      const private_membership::rlwe::PrivateMembershipRlweOprfResponse&
          oprf_response) override;
  void OnCheckMembershipQueryComplete(
      std::unique_ptr<std::string> response_body) override;
  void CheckIn() override;
  void OnCheckInComplete(std::unique_ptr<std::string> response_body) override;
  base::Time GetLastPingTimestamp() override;
  void SetLastPingTimestamp(base::Time ts) override;
  std::vector<private_membership::rlwe::RlwePlaintextId>
  GetPsmIdentifiersToQuery() override;
  std::optional<FresnelImportDataRequest> GenerateImportRequestBody() override;

 private:
  // Grant friend access for comprehensive testing of private/protected members.
  friend class ObservationImplTestBase;
  friend class ObservationImplDirectCheckInTest;

  // Generates the data that is transmitted with an observation period.
  std::optional<FresnelImportData> GenerateObservationImportData(int period);

  // Update the churn local state fields based on the new active status value.
  void UpdateLocalStateOnCheckInSuccess();

  // Check if the device needs to ping today.
  // Observation ping is only sent if cohort ping was successful in this month.
  bool IsDevicePingRequired();

  // Maintains callback that is executed once this use case is done running.
  base::OnceCallback<void()> callback_;

  // Maintain helper to manage the 28 bit active status bits, used for churn.
  std::unique_ptr<ActiveStatus> active_status_;

  // Manage Oprf, Query, and Import network requests on a single sequence.
  std::unique_ptr<network::SimpleURLLoader> url_loader_;

  // Automatically cancels callbacks when the referent of weakptr gets
  // destroyed.
  base::WeakPtrFactory<ObservationImpl> weak_factory_{this};
};

}  // namespace ash::report::device_metrics

#endif  // CHROMEOS_ASH_COMPONENTS_REPORT_DEVICE_METRICS_CHURN_OBSERVATION_IMPL_H_