1 // Copyright 2018 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "ash/policy/policy_recommendation_restorer.h"
7 #include "ash/session/session_controller_impl.h"
10 #include "base/check.h"
11 #include "base/notreached.h"
12 #include "base/stl_util.h"
13 #include "components/prefs/pref_change_registrar.h"
14 #include "components/prefs/pref_service.h"
15 #include "ui/base/user_activity/user_activity_detector.h"
21 // The amount of idle time after which recommended values are restored.
22 constexpr base::TimeDelta kRestoreDelayInMinutes =
23 base::TimeDelta::FromMinutes(1);
27 PolicyRecommendationRestorer::PolicyRecommendationRestorer() {
28 Shell::Get()->session_controller()->AddObserver(this);
31 PolicyRecommendationRestorer::~PolicyRecommendationRestorer() {
33 Shell::Get()->session_controller()->RemoveObserver(this);
36 void PolicyRecommendationRestorer::ObservePref(const std::string& pref_name) {
38 Shell::Get()->session_controller()->GetSigninScreenPrefService();
40 DCHECK(!base::Contains(pref_names_, pref_name));
42 if (!pref_change_registrar_) {
43 pref_change_registrar_ = std::make_unique<PrefChangeRegistrar>();
44 pref_change_registrar_->Init(prefs);
47 pref_change_registrar_->Add(
48 pref_name, base::BindRepeating(&PolicyRecommendationRestorer::Restore,
49 base::Unretained(this), true));
50 pref_names_.insert(pref_name);
51 Restore(false /* allow_delay */, pref_name);
54 void PolicyRecommendationRestorer::OnActiveUserPrefServiceChanged(
55 PrefService* pref_service) {
56 active_user_pref_connected_ = true;
61 void PolicyRecommendationRestorer::OnUserActivity(const ui::Event* event) {
62 if (restore_timer_.IsRunning())
63 restore_timer_.Reset();
66 void PolicyRecommendationRestorer::DisableForTesting() {
67 disabled_for_testing_ = true;
70 void PolicyRecommendationRestorer::Restore(bool allow_delay,
71 const std::string& pref_name) {
72 const PrefService::Preference* pref =
73 pref_change_registrar_->prefs()->FindPreference(pref_name);
79 if (!pref->GetRecommendedValue() || !pref->HasUserSetting())
82 if (active_user_pref_connected_) {
84 } else if (allow_delay) {
85 // Skip the delay if there has been no user input since |pref_name| is
86 // started observing recommended value.
87 const ui::UserActivityDetector* user_activity_detector =
88 ui::UserActivityDetector::Get();
89 if (user_activity_detector &&
90 user_activity_detector->last_activity_time().is_null()) {
97 else if (!disabled_for_testing_)
98 pref_change_registrar_->prefs()->ClearPref(pref->name());
101 void PolicyRecommendationRestorer::RestoreAll() {
102 for (const auto& pref_name : pref_names_)
103 Restore(false, pref_name);
106 void PolicyRecommendationRestorer::StartTimer() {
107 // Listen for user activity so that the timer can be reset while the user is
108 // active, causing it to fire only when the user remains idle for
109 // |kRestoreDelayInMinutes|.
110 ui::UserActivityDetector* user_activity_detector =
111 ui::UserActivityDetector::Get();
112 if (user_activity_detector && !user_activity_detector->HasObserver(this))
113 user_activity_detector->AddObserver(this);
115 // There should be a separate timer for each pref. However, in the common
116 // case of the user changing settings, a single timer is sufficient. This is
117 // because a change initiated by the user implies user activity, so that even
118 // if there was a separate timer per pref, they would all be reset at that
119 // point, causing them to fire at exactly the same time. In the much rarer
120 // case of a recommended value changing, a single timer is a close
121 // approximation of the behavior that would be obtained by resetting the timer
122 // for the affected pref only.
123 restore_timer_.Start(FROM_HERE, kRestoreDelayInMinutes,
124 base::BindOnce(&PolicyRecommendationRestorer::RestoreAll,
125 base::Unretained(this)));
128 void PolicyRecommendationRestorer::StopTimer() {
129 restore_timer_.Stop();
130 if (ui::UserActivityDetector::Get())
131 ui::UserActivityDetector::Get()->RemoveObserver(this);