Notify about major session changes events.

chrome/browser/ui/ash/session_state_delegate_chromeos.cc

 // Copyright (c) 2013 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.
 
 #include "chrome/browser/ui/ash/session_state_delegate_chromeos.h"
 
 #include "ash/multi_profile_uma.h"
 #include "ash/session_state_observer.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/prefs/pref_service.h"
+#include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/screen_locker.h"
 #include "chrome/browser/chromeos/login/user.h"
 #include "chrome/browser/chromeos/login/user_adding_screen.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
+#include "chromeos/login/login_state.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_source.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
-SessionStateDelegateChromeos::SessionStateDelegateChromeos() {
+SessionStateDelegateChromeos::SessionStateDelegateChromeos()
+    : session_state_(STATE_UNKNOWN) {

[Daniel Erat, 2014/04/10 16:30:32]

it'd be better to have a separate "initialized" member, add a "force" parameter
to SetSessionState(), or something similar. otherwise all of the observers are
forced to deal with an implementation detail of this class.

[Nikita (slow), 2014/04/10 17:22:51]

Done.

+  chromeos::LoginState::Get()->AddObserver(this);
+  chromeos::DBusThreadManager::Get()->
+      GetSessionManagerClient()->AddObserver(this);
   chromeos::UserManager::Get()->AddSessionStateObserver(this);
+  chromeos::UserAddingScreen::Get()->AddObserver(this);
+  notification_registrar_.Add(this,
+                              chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED,
+                              content::NotificationService::AllSources());
+  LoggedInStateChanged();
 }
 
 SessionStateDelegateChromeos::~SessionStateDelegateChromeos() {
+  chromeos::LoginState::Get()->RemoveObserver(this);
+  chromeos::DBusThreadManager::Get()->
+      GetSessionManagerClient()->RemoveObserver(this);
+  chromeos::UserManager::Get()->RemoveSessionStateObserver(this);
+  chromeos::UserAddingScreen::Get()->RemoveObserver(this);
 }
 
 content::BrowserContext* SessionStateDelegateChromeos::GetBrowserContextByIndex(
     ash::MultiProfileIndex index) {
   DCHECK_LT(index, NumberOfLoggedInUsers());
   chromeos::User* user =
       chromeos::UserManager::Get()->GetLRULoggedInUsers()[index];
   DCHECK(user);
   return chromeos::UserManager::Get()->GetProfileByUser(user);
 }
@@ skipping 64 matching lines @@
 }
 
 bool SessionStateDelegateChromeos::IsUserSessionBlocked() const {
   bool has_login_manager = CommandLine::ForCurrentProcess()->HasSwitch(
           chromeos::switches::kLoginManager);
   return (has_login_manager && !IsActiveUserSessionStarted()) ||
          IsScreenLocked() ||
          chromeos::UserAddingScreen::Get()->IsRunning();
 }
 
+ash::SessionStateDelegate::SessionState
+SessionStateDelegateChromeos::GetSessionState() const {
+  return session_state_;
+}
+
 const base::string16 SessionStateDelegateChromeos::GetUserDisplayName(
     ash::MultiProfileIndex index) const {
   DCHECK_LT(index, NumberOfLoggedInUsers());
   return chromeos::UserManager::Get()->
              GetLRULoggedInUsers()[index]->display_name();
 }
 
 const std::string SessionStateDelegateChromeos::GetUserEmail(
     ash::MultiProfileIndex index) const {
   DCHECK_LT(index, NumberOfLoggedInUsers());
@@ skipping 77 matching lines @@
 void SessionStateDelegateChromeos::AddSessionStateObserver(
     ash::SessionStateObserver* observer) {
   session_state_observer_list_.AddObserver(observer);
 }
 
 void SessionStateDelegateChromeos::RemoveSessionStateObserver(
     ash::SessionStateObserver* observer) {
   session_state_observer_list_.RemoveObserver(observer);
 }
 
+void SessionStateDelegateChromeos::LoggedInStateChanged() {
+  if (chromeos::LoginState::Get()->IsUserLoggedIn())
+    SetSessionState(STATE_SESSION);

[Daniel Erat, 2014/04/10 16:30:32]

nit:

  SetSessionState(chromeos::LoginState::Get()->IsUserLoggedIn() ?
      STATE_SESSION : STATE_LOGIN_PRIMARY);

[Nikita (slow), 2014/04/10 17:22:51]

Done.

+  else
+    SetSessionState(STATE_LOGIN_PRIMARY);
+}
+
+void SessionStateDelegateChromeos::ScreenIsLocked() {
+  SetSessionState(STATE_LOCK);
+}
+
+void SessionStateDelegateChromeos::ScreenIsUnlocked() {
+  SetSessionState(STATE_SESSION);
+}
+
 void SessionStateDelegateChromeos::ActiveUserChanged(
     const chromeos::User* active_user) {
+  SetSessionState(STATE_SESSION);

[Daniel Erat, 2014/04/10 16:30:32]

why is this necessary? shouldn't LoggedInStateChanged() also fire?

[Nikita (slow), 2014/04/10 17:22:51]

Done.

[Nikita (slow), 2014/04/10 17:22:51]

Done.

   FOR_EACH_OBSERVER(ash::SessionStateObserver,
                     session_state_observer_list_,
                     ActiveUserChanged(active_user->email()));
 }
 
 void SessionStateDelegateChromeos::UserAddedToSession(
     const chromeos::User* added_user) {
+  SetSessionState(STATE_SESSION);

[Daniel Erat, 2014/04/10 16:30:32]

why is this necessary? shouldn't OnUserAddingFinished() also fire?

[Nikita (slow), 2014/04/10 17:22:51]

Done.

   FOR_EACH_OBSERVER(ash::SessionStateObserver,
                     session_state_observer_list_,
                     UserAddedToSession(added_user->email()));
 }
+
+void SessionStateDelegateChromeos::OnUserAddingStarted() {
+  SetSessionState(STATE_LOGIN_SECONDARY);
+}
+
+void SessionStateDelegateChromeos::OnUserAddingFinished() {
+  SetSessionState(STATE_SESSION);
+}
+
+void SessionStateDelegateChromeos::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  switch (type) {
+    case chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED: {

[Daniel Erat, 2014/04/10 16:30:32]

this seems ugly. do we really need to watch for both
ScreenIsLocked/ScreenIsUnlocked and this notification? if so, why are there
cases where one happens but not the other?

[Nikita (slow), 2014/04/10 17:22:51]

Turns out ScreenLockerTest only creates ScreenLocker which in turn just fire
notification.

But I've removed STATE_LOCK completely per Steven's comment.

+      bool locked = *content::Details<bool>(details).ptr();
+      SetSessionState(locked ? STATE_LOCK : STATE_SESSION);
+      break;
+    }
+    default: {
+      NOTREACHED() << "Unknown notification type";
+      break;
+    }
+  }
+}
+
+void SessionStateDelegateChromeos::SetSessionState(SessionState new_state) {
+  if (session_state_ == new_state)
+    return;
+
+  session_state_ = new_state;
+  NotifySessionStateChanged();
+}
+
+void SessionStateDelegateChromeos::NotifySessionStateChanged() {
+  FOR_EACH_OBSERVER(ash::SessionStateObserver,
+                    session_state_observer_list_,
+                    SessionStateChanged(session_state_));
+}