1// Copyright 2014 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.
4
5#include "chrome/browser/net/prediction_options.h"
6
7#include "base/logging.h"
8#include "base/prefs/pref_service.h"
9#include "chrome/browser/profiles/profile_io_data.h"
10#include "chrome/common/pref_names.h"
11#include "components/pref_registry/pref_registry_syncable.h"
12#include "content/public/browser/browser_thread.h"
13#include "net/base/network_change_notifier.h"
14
15namespace chrome_browser_net {
16
17namespace {
18
19// Since looking up preferences and current network connection are presumably
20// both cheap, we do not cache them here.
21bool CanPrefetchAndPrerender(int network_prediction_options) {
22  switch (network_prediction_options) {
23    case NETWORK_PREDICTION_ALWAYS:
24      return true;
25    case NETWORK_PREDICTION_NEVER:
26      return false;
27    default:
28      DCHECK_EQ(NETWORK_PREDICTION_WIFI_ONLY, network_prediction_options);
29      return !net::NetworkChangeNotifier::IsConnectionCellular(
30                 net::NetworkChangeNotifier::GetConnectionType());
31  }
32}
33
34bool CanPreresolveAndPreconnect(int network_prediction_options) {
35  // DNS preresolution and TCP preconnect are performed even on cellular
36  // networks if the user setting is WIFI_ONLY.
37  return network_prediction_options != NETWORK_PREDICTION_NEVER;
38}
39
40}  // namespace
41
42void RegisterPredictionOptionsProfilePrefs(
43    user_prefs::PrefRegistrySyncable* registry) {
44  registry->RegisterIntegerPref(
45      prefs::kNetworkPredictionOptions,
46      NETWORK_PREDICTION_DEFAULT,
47      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
48}
49
50void MigrateNetworkPredictionUserPrefs(PrefService* pref_service) {
51  // Nothing to do if the user or this migration code has already set the new
52  // preference.
53  if (pref_service->GetUserPrefValue(prefs::kNetworkPredictionOptions))
54    return;
55
56  // Nothing to do if the user has not set the old preference.
57  const base::Value* network_prediction_enabled =
58      pref_service->GetUserPrefValue(prefs::kNetworkPredictionEnabled);
59  if (!network_prediction_enabled)
60    return;
61
62  bool value = false;
63  if (network_prediction_enabled->GetAsBoolean(&value)) {
64    pref_service->SetInteger(
65        prefs::kNetworkPredictionOptions,
66        value ? NETWORK_PREDICTION_WIFI_ONLY : NETWORK_PREDICTION_NEVER);
67  }
68}
69
70bool CanPrefetchAndPrerenderIO(ProfileIOData* profile_io_data) {
71  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
72  DCHECK(profile_io_data);
73  return CanPrefetchAndPrerender(
74      profile_io_data->network_prediction_options()->GetValue());
75}
76
77bool CanPrefetchAndPrerenderUI(PrefService* prefs) {
78  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
79  DCHECK(prefs);
80  return CanPrefetchAndPrerender(
81      prefs->GetInteger(prefs::kNetworkPredictionOptions));
82}
83
84bool CanPreresolveAndPreconnectIO(ProfileIOData* profile_io_data) {
85  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::IO));
86  DCHECK(profile_io_data);
87  return CanPreresolveAndPreconnect(
88      profile_io_data->network_prediction_options()->GetValue());
89}
90
91bool CanPreresolveAndPreconnectUI(PrefService* prefs) {
92  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
93  DCHECK(prefs);
94  return CanPreresolveAndPreconnect(
95      prefs->GetInteger(prefs::kNetworkPredictionOptions));
96}
97
98}  // namespace chrome_browser_net
99