Media Galleries: Add MediaGalleriesPreferences::GalleryChangeObserver class.

This lets interested parties such as media gallery permission dialogs get
notifications for preferences changes.

BUG=158849

Review URL: https://chromiumcodereview.appspot.com/12114019

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@179871 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 150 insertions, 29 deletions

diff --git a/chrome/browser/media_gallery/media_galleries_preferences.cc b/chrome/browser/media_gallery/media_galleries_preferences.cc
index abc08f9..6839bd9 100644
--- a/chrome/browser/media_gallery/media_galleries_preferences.cc
+++ b/chrome/browser/media_gallery/media_galleries_preferences.cc
@@ -136,10 +136,12 @@ FilePath MediaGalleryPrefInfo::AbsolutePath() const {
   return base_path.Append(path);
 }
 
+MediaGalleriesPreferences::GalleryChangeObserver::~GalleryChangeObserver() {}
+
 MediaGalleriesPreferences::MediaGalleriesPreferences(Profile* profile)
     : profile_(profile) {
   AddDefaultGalleriesIfFreshProfile();
-  InitFromPrefs();
+  InitFromPrefs(false /*no notification*/);
 }
 
 MediaGalleriesPreferences::~MediaGalleriesPreferences() {}
@@ -171,28 +173,46 @@ void MediaGalleriesPreferences::AddDefaultGalleriesIfFreshProfile() {
   }
 }
 
-void MediaGalleriesPreferences::InitFromPrefs() {
+void MediaGalleriesPreferences::InitFromPrefs(bool notify_observers) {
   known_galleries_.clear();
   device_map_.clear();
 
   PrefService* prefs = profile_->GetPrefs();
   const ListValue* list = prefs->GetList(
       prefs::kMediaGalleriesRememberedGalleries);
-  if (!list)
-    return;
+  if (list) {
+    for (ListValue::const_iterator it = list->begin();
+         it != list->end(); ++it) {
+      const DictionaryValue* dict = NULL;
+      if (!(*it)->GetAsDictionary(&dict))
+        continue;
+
+      MediaGalleryPrefInfo gallery_info;
+      if (!PopulateGalleryPrefInfoFromDictionary(*dict, &gallery_info))
+        continue;
+
+      known_galleries_[gallery_info.pref_id] = gallery_info;
+      device_map_[gallery_info.device_id].insert(gallery_info.pref_id);
+    }
+  }
+  if (notify_observers)
+    NotifyChangeObservers();
+}
 
-  for (ListValue::const_iterator it = list->begin(); it != list->end(); ++it) {
-    const DictionaryValue* dict = NULL;
-    if (!(*it)->GetAsDictionary(&dict))
-      continue;
+void MediaGalleriesPreferences::NotifyChangeObservers() {
+  FOR_EACH_OBSERVER(GalleryChangeObserver,
+                    gallery_change_observers_,
+                    OnGalleryChanged(this));
+}
 
-    MediaGalleryPrefInfo gallery_info;
-    if (!PopulateGalleryPrefInfoFromDictionary(*dict, &gallery_info))
-      continue;
+void MediaGalleriesPreferences::AddGalleryChangeObserver(
+    GalleryChangeObserver* observer) {
+  gallery_change_observers_.AddObserver(observer);
+}
 
-    known_galleries_[gallery_info.pref_id] = gallery_info;
-    device_map_[gallery_info.device_id].insert(gallery_info.pref_id);
-  }
+void MediaGalleriesPreferences::RemoveGalleryChangeObserver(
+    GalleryChangeObserver* observer) {
+  gallery_change_observers_.RemoveObserver(observer);
 }
 
 bool MediaGalleriesPreferences::LookUpGalleryByPath(
@@ -281,7 +301,7 @@ MediaGalleryPrefId MediaGalleriesPreferences::AddGallery(
           }
           if (update_gallery_name)
             dict->SetString(kMediaGalleriesDisplayNameKey, display_name);
-          InitFromPrefs();
+          InitFromPrefs(true /* notify observers */);
           break;
         }
       }
@@ -304,7 +324,7 @@ MediaGalleryPrefId MediaGalleriesPreferences::AddGallery(
   ListPrefUpdate update(prefs, prefs::kMediaGalleriesRememberedGalleries);
   ListValue* list = update.Get();
   list->Append(CreateGalleryPrefInfoDictionary(gallery_info));
-  InitFromPrefs();
+  InitFromPrefs(true /* notify observers */);
 
   return gallery_info.pref_id;
 }
@@ -342,7 +362,7 @@ void MediaGalleriesPreferences::ForgetGalleryById(MediaGalleryPrefId pref_id) {
       } else {
         list->Erase(iter, NULL);
       }
-      InitFromPrefs();
+      InitFromPrefs(true /* notify observers */);
       return;
     }
   }
diff --git a/chrome/browser/media_gallery/media_galleries_preferences.h b/chrome/browser/media_gallery/media_galleries_preferences.h
index 75c01f7..b712eba 100644
--- a/chrome/browser/media_gallery/media_galleries_preferences.h
+++ b/chrome/browser/media_gallery/media_galleries_preferences.h
@@ -11,6 +11,7 @@
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
+#include "base/observer_list.h"
 #include "base/string16.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 
@@ -75,9 +76,20 @@ typedef std::set<MediaGalleryPrefId> MediaGalleryPrefIdSet;
 // user profile.
 class MediaGalleriesPreferences : public ProfileKeyedService {
  public:
+  class GalleryChangeObserver {
+    public:
+     virtual void OnGalleryChanged(MediaGalleriesPreferences* pref) {}
+
+    protected:
+     virtual ~GalleryChangeObserver();
+  };
+
   explicit MediaGalleriesPreferences(Profile* profile);
   virtual ~MediaGalleriesPreferences();
 
+  void AddGalleryChangeObserver(GalleryChangeObserver* observer);
+  void RemoveGalleryChangeObserver(GalleryChangeObserver* observer);
+
   // Lookup a media gallery and fill in information about it and return true.
   // If the media gallery does not already exist, fill in as much of the
   // MediaGalleryPrefInfo struct as we can and return false.
@@ -90,12 +102,14 @@ class MediaGalleriesPreferences : public ProfileKeyedService {
       const std::string& device_id) const;
 
   // Teaches the registry about a new gallery.
+  // Returns the gallery's pref id.
   MediaGalleryPrefId AddGallery(const std::string& device_id,
                                 const string16& display_name,
                                 const FilePath& relative_path,
                                 bool user_added);
 
   // Teach the registry about a user added registry simply from the path.
+  // Returns the gallery's pref id.
   MediaGalleryPrefId AddGalleryByPath(const FilePath& path);
 
   // Removes the gallery identified by |id| from the store.
@@ -130,7 +144,13 @@ class MediaGalleriesPreferences : public ProfileKeyedService {
   void AddDefaultGalleriesIfFreshProfile();
 
   // Builds |known_galleries_| from the persistent store.
-  void InitFromPrefs();
+  // Notifies GalleryChangeObservers if |notify_observers| is true.
+  void InitFromPrefs(bool notify_observers);
+
+  // Notifies |gallery_change_observers_| about changes in |known_galleries_|.
+  void NotifyChangeObservers();
+
+  extensions::ExtensionPrefs* GetExtensionPrefs() const;
 
   // The profile that owns |this|.
   Profile* profile_;
@@ -142,7 +162,7 @@ class MediaGalleriesPreferences : public ProfileKeyedService {
   // All pref ids in |device_map_| are also in |known_galleries_|.
   DeviceIdPrefIdsMap device_map_;
 
-  extensions::ExtensionPrefs* GetExtensionPrefs() const;
+  ObserverList<GalleryChangeObserver> gallery_change_observers_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaGalleriesPreferences);
 };
diff --git a/chrome/browser/media_gallery/media_galleries_preferences_unittest.cc b/chrome/browser/media_gallery/media_galleries_preferences_unittest.cc
index 66e56b5..2ceceeb 100644
--- a/chrome/browser/media_gallery/media_galleries_preferences_unittest.cc
+++ b/chrome/browser/media_gallery/media_galleries_preferences_unittest.cc
@@ -49,6 +49,29 @@ class MediaStorageUtilTest : public MediaStorageUtil {
   }
 };
 
+class MockGalleryChangeObserver
+    : public MediaGalleriesPreferences::GalleryChangeObserver {
+ public:
+  explicit MockGalleryChangeObserver(MediaGalleriesPreferences* pref)
+      : pref_(pref),
+        notifications_(0) {}
+  virtual ~MockGalleryChangeObserver() {}
+
+  int notifications() const { return notifications_;}
+
+ private:
+  // MediaGalleriesPreferences::GalleryChangeObserver implementation.
+  virtual void OnGalleryChanged(MediaGalleriesPreferences* pref) OVERRIDE {
+    EXPECT_EQ(pref_, pref);
+    ++notifications_;
+  }
+
+  MediaGalleriesPreferences* pref_;
+  int notifications_;
+
+  DISALLOW_COPY_AND_ASSIGN(MockGalleryChangeObserver);
+};
+
 class MediaGalleriesPreferencesTest : public testing::Test {
  public:
   typedef std::map<std::string /*device id*/, MediaGalleryPrefIdSet>
@@ -117,7 +140,7 @@ class MediaGalleriesPreferencesTest : public testing::Test {
     for (MediaGalleriesPrefInfoMap::const_iterator it = known_galleries.begin();
          it != known_galleries.end();
          ++it) {
-      VerifyGalleryInfo(&it->second, it->first);
+      VerifyGalleryInfo(it->second, it->first);
     }
 
     for (DeviceIdPrefIdsMap::const_iterator it = expected_device_map.begin();
@@ -142,16 +165,16 @@ class MediaGalleriesPreferencesTest : public testing::Test {
     EXPECT_EQ(0U, galleries_for_no.size());
   }
 
-  void VerifyGalleryInfo(const MediaGalleryPrefInfo* actual,
+  void VerifyGalleryInfo(const MediaGalleryPrefInfo& actual,
                          MediaGalleryPrefId expected_id) const {
     MediaGalleriesPrefInfoMap::const_iterator in_expectation =
       expected_galleries_.find(expected_id);
-    EXPECT_FALSE(in_expectation == expected_galleries_.end());
-    EXPECT_EQ(in_expectation->second.pref_id, actual->pref_id);
-    EXPECT_EQ(in_expectation->second.display_name, actual->display_name);
-    EXPECT_EQ(in_expectation->second.device_id, actual->device_id);
-    EXPECT_EQ(in_expectation->second.path.value(), actual->path.value());
-    EXPECT_EQ(in_expectation->second.type, actual->type);
+    ASSERT_FALSE(in_expectation == expected_galleries_.end())  << expected_id;
+    EXPECT_EQ(in_expectation->second.pref_id, actual.pref_id);
+    EXPECT_EQ(in_expectation->second.display_name, actual.display_name);
+    EXPECT_EQ(in_expectation->second.device_id, actual.device_id);
+    EXPECT_EQ(in_expectation->second.path.value(), actual.path.value());
+    EXPECT_EQ(in_expectation->second.type, actual.type);
   }
 
   MediaGalleriesPreferences* gallery_prefs() {
@@ -261,10 +284,10 @@ TEST_F(MediaGalleriesPreferencesTest, GalleryManagement) {
   MediaGalleryPrefInfo gallery_info;
   EXPECT_TRUE(gallery_prefs()->LookUpGalleryByPath(MakePath("new_auto"),
                                                    &gallery_info));
-  VerifyGalleryInfo(&gallery_info, auto_id);
+  VerifyGalleryInfo(gallery_info, auto_id);
   EXPECT_TRUE(gallery_prefs()->LookUpGalleryByPath(MakePath("new_user"),
                                                    &gallery_info));
-  VerifyGalleryInfo(&gallery_info, user_added_id);
+  VerifyGalleryInfo(gallery_info, user_added_id);
 
   path = MakePath("other");
   EXPECT_FALSE(gallery_prefs()->LookUpGalleryByPath(path, &gallery_info));
@@ -559,6 +582,64 @@ TEST_F(MediaGalleriesPreferencesTest, MultipleGalleriesPerDevices) {
   Verify();
 }
 
+TEST_F(MediaGalleriesPreferencesTest, GalleryChangeObserver) {
+  // Start with one observer.
+  MockGalleryChangeObserver observer1(gallery_prefs());
+  gallery_prefs()->AddGalleryChangeObserver(&observer1);
+
+  // Add a new auto detected gallery.
+  string16 device_name = ASCIIToUTF16("NewAutoGallery");
+  FilePath path = MakePath("new_auto");
+  std::string device_id;
+  FilePath relative_path;
+  MediaStorageUtil::GetDeviceInfoFromPath(path, &device_id, NULL,
+                                          &relative_path);
+  MediaGalleryPrefId auto_id =
+      gallery_prefs()->AddGallery(device_id, device_name, relative_path,
+                                  false /*auto*/);
+  EXPECT_EQ(default_galleries_count() + 1UL, auto_id);
+  AddGalleryExpectation(auto_id, device_name, device_id, relative_path,
+                        MediaGalleryPrefInfo::kAutoDetected);
+  EXPECT_EQ(1, observer1.notifications());
+
+  // Add a second observer.
+  MockGalleryChangeObserver observer2(gallery_prefs());
+  gallery_prefs()->AddGalleryChangeObserver(&observer2);
+
+  // Add a new user added gallery.
+  path = MakePath("new_user");
+  MediaStorageUtil::GetDeviceInfoFromPath(path, &device_id, NULL,
+                                          &relative_path);
+  device_name = ASCIIToUTF16("NewUserGallery");
+  MediaGalleryPrefId user_added_id =
+      gallery_prefs()->AddGallery(device_id, device_name, relative_path,
+                                  true /*user*/);
+  AddGalleryExpectation(user_added_id, device_name, device_id, relative_path,
+                        MediaGalleryPrefInfo::kUserAdded);
+  EXPECT_EQ(default_galleries_count() + 2UL, user_added_id);
+  EXPECT_EQ(2, observer1.notifications());
+  EXPECT_EQ(1, observer2.notifications());
+
+  // Remove the first observer.
+  gallery_prefs()->RemoveGalleryChangeObserver(&observer1);
+
+  // Remove an auto added gallery (i.e. make it blacklisted).
+  gallery_prefs()->ForgetGalleryById(auto_id);
+  expected_galleries_[auto_id].type = MediaGalleryPrefInfo::kBlackListed;
+  expected_galleries_for_all.erase(auto_id);
+
+  EXPECT_EQ(2, observer1.notifications());
+  EXPECT_EQ(2, observer2.notifications());
+
+  // Remove a user added gallery and it should go away.
+  gallery_prefs()->ForgetGalleryById(user_added_id);
+  expected_galleries_.erase(user_added_id);
+  expected_device_map[device_id].erase(user_added_id);
+
+  EXPECT_EQ(2, observer1.notifications());
+  EXPECT_EQ(3, observer2.notifications());
+}
+
 }  // namespace
 
 }  // namespace chrome