Move Ownership of IMUI to HistoryService.

chrome/browser/history/in_memory_url_index.cc

Index: chrome/browser/history/in_memory_url_index.cc
===================================================================
--- chrome/browser/history/in_memory_url_index.cc	(revision 120346)
+++ chrome/browser/history/in_memory_url_index.cc	(working copy)
@@ -5,56 +5,85 @@
 #include "chrome/browser/history/in_memory_url_index.h"
 
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/history/history_notifications.h"
 #include "chrome/browser/history/url_database.h"
+#include "chrome/browser/history/url_index_private_data.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_source.h"
 
 using in_memory_url_index::InMemoryURLIndexCacheItem;
 
 namespace history {
 
-InMemoryURLIndex::InMemoryURLIndex(const FilePath& history_dir)
-    : history_dir_(history_dir),
+InMemoryURLIndex::RebuildPrivateDataFromHistoryDBTask::
+    RebuildPrivateDataFromHistoryDBTask(InMemoryURLIndex* index)
+    : index_(index),
+      succeeded_(false) {}
+
+InMemoryURLIndex::RebuildPrivateDataFromHistoryDBTask::
+    ~RebuildPrivateDataFromHistoryDBTask() {}
+
+bool InMemoryURLIndex::RebuildPrivateDataFromHistoryDBTask::RunOnDBThread(
+    HistoryBackend* backend,
+    HistoryDatabase* db) {
+  data_.reset(URLIndexPrivateData::RebuildFromHistory(db));
+  succeeded_ = data_.get() && !data_->history_info_map_.empty();
+  if (!succeeded_)
+    data_.reset();
+  return true;
+}
+
+void InMemoryURLIndex::RebuildPrivateDataFromHistoryDBTask::
+    DoneRunOnMainThread() {
+  if (succeeded_)
+    index_->DoneRebuidingPrivateDataFromHistoryDB(data_.release());
+}
+
+InMemoryURLIndex::InMemoryURLIndex(Profile* profile,
+                                   const FilePath& history_dir,
+                                   const std::string& languages)
+    : profile_(profile),
+      history_dir_(history_dir),
       private_data_(new URLIndexPrivateData),
-      cached_at_shutdown_(false) {
+      shutdown_(false),
+      needs_to_be_cached_(false) {
+  private_data_->set_languages(languages);
+  if (profile) {
+    // TODO(mrossetti): Register for language change notifications.
+    content::Source<Profile> source(profile);
+    registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URL_VISITED, source);
+    registrar_.Add(this, chrome::NOTIFICATION_HISTORY_TYPED_URLS_MODIFIED,
+                   source);
+    registrar_.Add(this, chrome::NOTIFICATION_HISTORY_URLS_DELETED, source);
+  }
 }
 
 // Called only by unit tests.
 InMemoryURLIndex::InMemoryURLIndex()
-    : private_data_(new URLIndexPrivateData),
-      cached_at_shutdown_(false) {
+    : profile_(NULL),
+      private_data_(new URLIndexPrivateData),
+      shutdown_(false),
+      needs_to_be_cached_(false) {
 }
 
 InMemoryURLIndex::~InMemoryURLIndex() {
   // If there was a history directory (which there won't be for some unit tests)
   // then insure that the cache has already been saved.
-  DCHECK(history_dir_.empty() || cached_at_shutdown_);
+  DCHECK(history_dir_.empty() || !needs_to_be_cached_);
 }
 
-bool InMemoryURLIndex::Init(URLDatabase* history_db,
-                            const std::string& languages) {
-  // TODO(mrossetti): Register for profile/language change notifications.
-  private_data_->set_languages(languages);
-  FilePath cache_file_path;
-  return (GetCacheFilePath(&cache_file_path) &&
-          private_data_->RestoreFromFile(cache_file_path)) ||
-      ReloadFromHistory(history_db);
+void InMemoryURLIndex::Init() {
+  RestoreFromCacheFile();
 }
 
-bool InMemoryURLIndex::ReloadFromHistory(history::URLDatabase* history_db) {
-  if (!private_data_->ReloadFromHistory(history_db))
-    return false;
-  FilePath cache_file_path;
-  if (GetCacheFilePath(&cache_file_path))
-    private_data_->SaveToFile(cache_file_path);
-  return true;
-}
-
 void InMemoryURLIndex::ShutDown() {
-  // Write our cache.
-  FilePath cache_file_path;
-  if (!GetCacheFilePath(&cache_file_path))
-    return;
-  private_data_->SaveToFile(cache_file_path);
-  cached_at_shutdown_ = true;
+  registrar_.RemoveAll();
+  cache_reader_consumer_.CancelAllRequests();
+  shutdown_ = true;
+  SaveToCacheFile();
+  needs_to_be_cached_ = false;
 }
 
 void InMemoryURLIndex::ClearPrivateData() {
@@ -68,19 +97,120 @@
   return true;
 }
 
-// Querying and Updating -------------------------------------------------------
+// Querying --------------------------------------------------------------------
 
 ScoredHistoryMatches InMemoryURLIndex::HistoryItemsForTerms(
     const string16& term_string) {
   return private_data_->HistoryItemsForTerms(term_string);
 }
 
-void InMemoryURLIndex::UpdateURL(URLID row_id, const URLRow& row) {
-  private_data_->UpdateURL(row_id, row);
+// Updating --------------------------------------------------------------------
+
+void InMemoryURLIndex::Observe(int notification_type,
+                               const content::NotificationSource& source,
+                               const content::NotificationDetails& details) {
+  switch (notification_type) {
+    case chrome::NOTIFICATION_HISTORY_URL_VISITED:
+      OnURLVisited(content::Details<URLVisitedDetails>(details).ptr());
+      break;
+    case chrome::NOTIFICATION_HISTORY_TYPED_URLS_MODIFIED:
+      OnURLsModified(
+          content::Details<history::URLsModifiedDetails>(details).ptr());
+      break;
+    case chrome::NOTIFICATION_HISTORY_URLS_DELETED:
+      OnURLsDeleted(
+          content::Details<history::URLsDeletedDetails>(details).ptr());
+      break;
+    case chrome::NOTIFICATION_HISTORY_LOADED: {
+      registrar_.Remove(this, chrome::NOTIFICATION_HISTORY_LOADED,
+                        content::Source<Profile>(profile_));
+      ScheduleRebuildFromHistory();
+      break;
+    }
+    default:
+      // For simplicity, the unit tests send us all notifications, even when
+      // we haven't registered for them, so don't assert here.
+      break;
+  }
 }
 
-void InMemoryURLIndex::DeleteURL(URLID row_id) {
-  private_data_->DeleteURL(row_id);
+void InMemoryURLIndex::OnURLVisited(const URLVisitedDetails* details) {
+  needs_to_be_cached_ |= private_data_->UpdateURL(details->row);
 }
 
+void InMemoryURLIndex::OnURLsModified(const URLsModifiedDetails* details) {
+  for (URLRows::const_iterator row = details->changed_urls.begin();
+       row != details->changed_urls.end(); ++row)
+    needs_to_be_cached_ |= private_data_->UpdateURL(*row);
+}
+
+void InMemoryURLIndex::OnURLsDeleted(const URLsDeletedDetails* details) {
+  if (details->all_history) {
+    ClearPrivateData();
+    needs_to_be_cached_ = true;
+  } else {
+    for (URLRows::const_iterator row = details->rows.begin();
+         row != details->rows.end(); ++row)
+      needs_to_be_cached_ |= private_data_->DeleteURL(row->url());
+  }
+}
+
+// Restoring from Cache --------------------------------------------------------
+
+void InMemoryURLIndex::RestoreFromCacheFile() {
+  FilePath path;
+  if (GetCacheFilePath(&path) && !shutdown_)
+    DoRestoreFromCacheFile(path);
+}
+
+void InMemoryURLIndex::DoRestoreFromCacheFile(const FilePath& path) {
+  if (private_data_->RestoreFromFile(path))
+    return;
+
+  // When unable to restore from the cache file we must rebuild from the
+  // history database.
+  HistoryService* service = profile_->GetHistoryServiceWithoutCreating();
+  if (service && service->backend_loaded())
+    ScheduleRebuildFromHistory();
+  // We must wait to rebuild until the history backend has been loaded.
+  registrar_.Add(this, chrome::NOTIFICATION_HISTORY_LOADED,
+                 content::Source<Profile>(profile_));
+}
+
+// Restoring from the History DB -----------------------------------------------
+
+void InMemoryURLIndex::ScheduleRebuildFromHistory() {
+  HistoryService* service =
+      profile_->GetHistoryService(Profile::EXPLICIT_ACCESS);
+  service->ScheduleDBTask(
+      new InMemoryURLIndex::RebuildPrivateDataFromHistoryDBTask(this),
+      &cache_reader_consumer_);
+}
+
+void InMemoryURLIndex::DoneRebuidingPrivateDataFromHistoryDB(
+    URLIndexPrivateData* data) {
+  scoped_ptr<URLIndexPrivateData> private_data(data);
+  private_data_.swap(private_data);
+  // Cache the newly rebuilt index.
+  FilePath cache_file_path;
+  if (GetCacheFilePath(&cache_file_path))
+    private_data_->SaveToFile(cache_file_path);
+}
+
+void InMemoryURLIndex::RebuildFromHistory(HistoryDatabase* history_db) {
+  private_data_.reset(URLIndexPrivateData::RebuildFromHistory(history_db));
+}
+
+// Saving to Cache -------------------------------------------------------------
+
+void InMemoryURLIndex::SaveToCacheFile() {
+  FilePath path;
+  if (GetCacheFilePath(&path))
+    DoSaveToCacheFile(path);
+}
+
+void InMemoryURLIndex::DoSaveToCacheFile(const FilePath& path) {
+  private_data_->SaveToFile(path);
+}
+
 }  // namespace history