chrome/browser/chromeos/system/timezone_resolver_manager.h

// Copyright 2016 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_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_
#define CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_

#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "chromeos/timezone/timezone_resolver.h"
#include "components/prefs/pref_change_registrar.h"

class PrefService;

namespace chromeos {
namespace system {

class TimeZoneResolverManager : public TimeZoneResolver::Delegate {
 public:
  class Observer {
   public:
    // This is always called when UpdateTimezoneResolver() is finished.
    // As UpdateTimezoneResolver() is called once any of the relevant
    // preferences are updated, it can be used to observe all time zone -related
    // preference changes.
    virtual void OnTimeZoneResolverUpdated() = 0;
  };

  // This is stored as a prefs::kResolveTimezoneByGeolocationMethod
  // and prefs::kResolveDeviceTimezoneByGeolocationMethod preferences.
  enum class TimeZoneResolveMethod {
    DISABLED = 0,
    IP_ONLY = 1,
    SEND_WIFI_ACCESS_POINTS = 2,
    SEND_ALL_LOCATION_INFO = 3,
    METHODS_NUMBER = 4
  };

  TimeZoneResolverManager();
  ~TimeZoneResolverManager() override;

  // This sets primary_user_prefs_.
  void SetPrimaryUserPrefs(PrefService* pref_service);

  // TimeZoneResolver::Delegate overrides:
  bool ShouldSendWiFiGeolocationData() override;

  // TimeZoneResolver::Delegate overrides:
  bool ShouldSendCellularGeolocationData() override;

  // Starts or stops TimezoneResolver according to currect settings.
  void UpdateTimezoneResolver();

  void AddObserver(Observer* observer);
  void RemoveObserver(Observer* observer);

  // Returns true if result of timezone resolve should be applied to
  // system timezone (preferences might have changed since request was started).
  bool ShouldApplyResolvedTimezone();

  // Returns true if TimeZoneResolver should be running and taking in account
  // all configuration data.
  bool TimeZoneResolverShouldBeRunning();

  // Convert kResolveTimezoneByGeolocationMethod /
  // kResolveDeviceTimezoneByGeolocationMethod preference value to
  // TimeZoneResolveMethod. Defaults to DISABLED for unknown values.
  static TimeZoneResolveMethod TimeZoneResolveMethodFromInt(int value);

  // Returns user preference value if time zone is not managed.
  // Otherwise returns effective time zone resolve method.
  // If |check_policy| is true, effective method calculation will also
  // take into account current policy values.
  static TimeZoneResolveMethod GetEffectiveUserTimeZoneResolveMethod(
      const PrefService* user_prefs,
      bool check_policy);

  // Returns true if time zone resolution settings are policy controlled and
  // thus cannot be changed by user.
  static bool IsTimeZoneResolutionPolicyControlled();

 private:
  int GetTimezoneManagementSetting();

  // Local State initialization observer.
  void OnLocalStateInitialized(bool initialized);

  base::ObserverList<Observer> observers_;

  // This is non-null only after user logs in.
  PrefService* primary_user_prefs_ = nullptr;

  // This is used to subscribe to policy preference.
  PrefChangeRegistrar local_state_pref_change_registrar_;

  // True if initial policy values are loaded.
  bool local_state_initialized_ = false;

  // True if TimeZoneResolverManager may start/stop on its own.
  // Becomes true after UpdateTimezoneResolver() has been called at least once.
  bool initialized_ = false;

  base::WeakPtrFactory<TimeZoneResolverManager> weak_factory_;

  DISALLOW_COPY_AND_ASSIGN(TimeZoneResolverManager);
};

}  // namespace system
}  // namespace chromeos

#endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_