Implement SyncableServices in TemplateURLService. Add related unittests.

chrome/browser/search_engines/template_url_service.h

Index: chrome/browser/search_engines/template_url_service.h
===================================================================
--- chrome/browser/search_engines/template_url_service.h	(revision 96768)
+++ chrome/browser/search_engines/template_url_service.h	(working copy)
@@ -17,6 +17,8 @@
 #include "chrome/browser/profiles/profile_keyed_service.h"
 #include "chrome/browser/search_engines/search_host_to_urls_map.h"
 #include "chrome/browser/search_engines/template_url_id.h"
+#include "chrome/browser/sync/api/sync_change.h"
+#include "chrome/browser/sync/api/syncable_service.h"
 #include "chrome/browser/webdata/web_data_service.h"
 #include "content/common/notification_observer.h"
 #include "content/common/notification_registrar.h"
@@ -28,6 +30,7 @@
 class PrefSetObserver;
 class SearchHostToURLsMap;
 class SearchTermsData;
+class SyncData;
 class TemplateURLServiceObserver;
 class TemplateURLRef;
 
@@ -58,12 +61,14 @@
 
 class TemplateURLService : public WebDataServiceConsumer,
                            public ProfileKeyedService,
-                           public NotificationObserver {
+                           public NotificationObserver,
+                           public SyncableService {
  public:
   typedef std::map<std::string, std::string> QueryTerms;
   typedef std::vector<const TemplateURL*> TemplateURLVector;
   // Type for a static function pointer that acts as a time source.
   typedef base::Time(TimeProvider)();
+  typedef std::map<std::string, SyncData> SyncDataMap;
 
   // Struct used for initializing the data store with fake data.
   // Each initializer is mapped to a TemplateURL.
@@ -124,6 +129,12 @@
   // retains ownership of it.
   const TemplateURL* GetTemplateURLForKeyword(const string16& keyword) const;
 
+  // Looks up |sync_guid| and returns the element it maps to.  Returns NULL if
+  // the guid was not found.
+  // The caller should not try to delete the returned pointer; the data store
+  // retains ownership of it.
+  const TemplateURL* GetTemplateURLForGUID(const std::string& sync_guid) const;
+
   // Returns the first TemplateURL found with a URL using the specified |host|,
   // or NULL if there are no such TemplateURLs
   const TemplateURL* GetTemplateURLForHost(const std::string& host) const;
@@ -233,6 +244,34 @@
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
+  // SyncableService implementation.
+
+  // Returns all syncable TemplateURLs from this model as SyncData. This should
+  // include every search engine and no Extension keywords.
+  virtual SyncDataList GetAllSyncData(syncable::ModelType type) const OVERRIDE;
+  // Process new search engine changes from Sync, merging them into our local
+  // data. This may send notifications if local search engines are added,
+  // updated or removed.
+  virtual SyncError ProcessSyncChanges(
+      const tracked_objects::Location& from_here,
+      const SyncChangeList& change_list) OVERRIDE;
+  // Merge initial search engine data from Sync and push any local changes up
+  // to Sync. This may send notifications if local search engines are added,
+  // updated or removed.
+  virtual SyncError MergeDataAndStartSyncing(
+      syncable::ModelType type,
+      const SyncDataList& initial_sync_data,
+      SyncChangeProcessor* sync_processor) OVERRIDE;
+  virtual void StopSyncing(syncable::ModelType type) OVERRIDE;
+
+  // Processes a local TemplateURL change for Sync. |turl| is the TemplateURL
+  // that has been modified, and |type| is the Sync ChangeType that took place.
+  // This may send a new SyncChange to the cloud. If our model has not yet been
+  // associated with Sync, or if this is triggered by a Sync change, then this
+  // does nothing.
+  void ProcessTemplateURLChange(const TemplateURL* turl,
+                                SyncChange::SyncChangeType type);
+
   Profile* profile() const { return profile_; }
 
   void SetSearchEngineDialogSlot(int slot) {
@@ -246,6 +285,18 @@
   // Registers the preferences used to save a TemplateURL to prefs.
   static void RegisterUserPrefs(PrefService* prefs);
 
+  // Returns a SyncData with a sync representation of the search engine data
+  // from |turl|.
+  static SyncData CreateSyncDataFromTemplateURL(const TemplateURL& turl);
+
+  // Returns a heap-allocated TemplateURL, populated by |sync_data|'s fields.
+  // This does the opposite of CreateSyncDataFromTemplateURL. The caller owns
+  // the returned TemplateURL*.
+  static TemplateURL* CreateTemplateURLFromSyncData(const SyncData& sync_data);
+
+  // Returns a map mapping Sync GUIDs to pointers to SyncData.
+  static SyncDataMap CreateGUIDToSyncDataMap(const SyncDataList& sync_data);
+
 #if defined(UNIT_TEST)
   // Set a different time provider function, such as
   // base::MockTimeProvider::StaticNow, when testing calls to base::Time::Now.
@@ -272,9 +323,24 @@
                            DontUpdateKeywordSearchForNonReplaceable);
   FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceTest, ChangeGoogleBaseValue);
   FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceTest, MergeDeletesUnusedProviders);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           CreateSyncDataFromTemplateURL);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           CreateTemplateURLFromSyncData);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest, UniquifyKeyword);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           ResolveSyncKeywordConflict);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           FindDuplicateOfSyncTemplateURL);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           MergeSyncAndLocalURLDuplicates);
+  FRIEND_TEST_ALL_PREFIXES(TemplateURLServiceSyncTest,
+                           CreateGUIDToSyncDataMap);
+
   friend class TemplateURLServiceTestUtil;
 
   typedef std::map<string16, const TemplateURL*> KeywordToTemplateMap;
+  typedef std::map<std::string, const TemplateURL*> GUIDToTemplateMap;
 
   // Helper functor for FindMatchingKeywords(), for finding the range of
   // keywords which begin with a prefix.
@@ -395,11 +461,51 @@
       const TemplateURL** default_search_provider,
       const TemplateURL* default_from_prefs);
 
+  // Resets the sync GUID of the specified TemplateURL and persists the change
+  // to the database. This does not notify observers.
+  void ResetTemplateURLGUID(const TemplateURL* url, const std::string& guid);
+
+  // Attempts to generate a unique keyword for |turl| based on its original
+  // keyword. If its keyword is already unique, that is returned. Otherwise, it
+  // tries to return the autogenerated keyword if that is unique to the Service,
+  // and finally it repeatedly appends special characters to the keyword until
+  // it is unique to the Service.
+  string16 UniquifyKeyword(const TemplateURL& turl) const;
+
+  // Given a TemplateURL from Sync, resolves any keyword conflicts by checking
+  // the local keywords and uniquifying either the cloud keyword or a
+  // conflicting local keyword (whichever is older). If the cloud TURL is
+  // changed, then an appropriate SyncChange is appended to |change_list|. If
+  // a local TURL is changed, the service is updated with the new keyword. If
+  // there was no conflict to begin with, this does nothing. In the case of tied
+  // last_modified dates, |sync_turl| wins. Returns true iff there was a
+  // conflict.
+  bool ResolveSyncKeywordConflict(TemplateURL* sync_turl,
+                                  SyncChangeList& change_list);
+
+  // Returns a TemplateURL from the service that has the same keyword and search
+  // URL as |sync_turl|, if it exists.
+  const TemplateURL* FindDuplicateOfSyncTemplateURL(
+      const TemplateURL& sync_turl);
+
+  // Given a TemplateURL from the cloud and a local matching duplicate found by
+  // FindDuplcateOfSyncTemplateURL, merges the two. If |sync_url| is newer, this
+  // replaces |local_url| with |sync_url| using the service's Remove and Add.
+  // If |local_url| is newer, this copies the GUID from |sync_url| over to
+  // |local_url| and adds an update to change_list to notify the server of the
+  // change.
+  void MergeSyncAndLocalURLDuplicates(TemplateURL* sync_url,
+                                      TemplateURL* local_url,
+                                      SyncChangeList& change_list);
+
   NotificationRegistrar registrar_;
 
   // Mapping from keyword to the TemplateURL.
   KeywordToTemplateMap keyword_to_template_map_;
 
+  // Mapping from Sync GUIDs to the TemplateURL.
+  GUIDToTemplateMap guid_to_template_map_;
+
   TemplateURLVector template_urls_;
 
   ObserverList<TemplateURLServiceObserver> model_observers_;
@@ -457,6 +563,19 @@
   // Function returning current time in base::Time units.
   TimeProvider* time_provider_;
 
+  // Do we have an active association between the TemplateURLs and sync models?
+  // Set in MergeDataAndStartSyncing, reset in StopSyncing. While this is not
+  // set, we ignore any local search engine changes (when we start syncing we
+  // will look up the most recent values anyways).
+  bool models_associated_;
+
+  // Whether we're currently processing changes from the syncer. While this is
+  // true, we ignore any local search engine changes, since we triggered them.
+  bool processing_syncer_changes_;
+
+  // Sync's SyncChange handler. We push all our changes through this.
+  SyncChangeProcessor* sync_processor_;
+
   DISALLOW_COPY_AND_ASSIGN(TemplateURLService);
 };