Split TabRestoreService into InMemoryTRS and PersistentTRS

chrome/browser/sessions/tab_restore_service.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_H_
 #define CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_H_
 
 #include <list>
-#include <set>
+#include <string>
 #include <vector>
 
-#include "base/gtest_prod_util.h"
-#include "base/observer_list.h"
+#include "base/memory/ref_counted.h"
 #include "base/time.h"
-#include "chrome/browser/sessions/base_session_service.h"
+#include "chrome/browser/profiles/profile_keyed_service.h"
 #include "chrome/browser/sessions/session_id.h"
 #include "chrome/browser/sessions/session_types.h"
 #include "content/public/browser/session_storage_namespace.h"
 #include "webkit/glue/window_open_disposition.h"
 
-class Profile;
 class TabRestoreServiceDelegate;
 class TabRestoreServiceObserver;
-struct SessionWindow;
 
 namespace content {
-class NavigationController;
 class SessionStorageNamespace;
 class WebContents;
 }
 
 // TabRestoreService is responsible for maintaining the most recently closed
 // tabs and windows. When a tab is closed
 // TabRestoreService::CreateHistoricalTab is invoked and a Tab is created to
 // represent the tab. Similarly, when a browser is closed, BrowserClosing is
 // invoked and a Window is created to represent the window.
 //
 // To restore a tab/window from the TabRestoreService invoke RestoreEntryById
 // or RestoreMostRecentEntry.
 //
 // To listen for changes to the set of entries managed by the TabRestoreService
 // add an observer.
-class TabRestoreService : public BaseSessionService {
+class TabRestoreService : public ProfileKeyedService {
  public:
   // Interface used to allow the test to provide a custom time.
   class TimeFactory {
    public:
     virtual ~TimeFactory();
     virtual base::Time TimeNow() = 0;
   };
 
   // The type of entry.
   enum Type {
@@ skipping 65 matching lines @@
 
     // Index of the selected tab.
     int selected_tab_index;
 
     // If an application window, the name of the app.
     std::string app_name;
   };
 
   typedef std::list<Entry*> Entries;
 
-  // Creates a new TabRestoreService and provides an object that provides the
-  // current time. The TabRestoreService does not take ownership of the
-  // |time_factory_|.
-  TabRestoreService(Profile* profile, TimeFactory* time_factory_ = NULL);
-
   virtual ~TabRestoreService();
 
   // Adds/removes an observer. TabRestoreService does not take ownership of
   // the observer.
-  void AddObserver(TabRestoreServiceObserver* observer);
-  void RemoveObserver(TabRestoreServiceObserver* observer);
+  virtual void AddObserver(TabRestoreServiceObserver* observer) = 0;
+  virtual void RemoveObserver(TabRestoreServiceObserver* observer) = 0;
 
   // Creates a Tab to represent |contents| and notifies observers the list of
   // entries has changed.
-  void CreateHistoricalTab(content::WebContents* contents, int index);
+  virtual void CreateHistoricalTab(content::WebContents* contents,
+                                   int index) = 0;
 
   // Invoked when a browser is closing. If |delegate| is a tabbed browser with
   // at least one tab, a Window is created, added to entries and observers are
   // notified.
-  void BrowserClosing(TabRestoreServiceDelegate* delegate);
+  virtual void BrowserClosing(TabRestoreServiceDelegate* delegate) = 0;
 
   // Invoked when the browser is done closing.
-  void BrowserClosed(TabRestoreServiceDelegate* delegate);
+  virtual void BrowserClosed(TabRestoreServiceDelegate* delegate) = 0;
 
   // Removes all entries from the list and notifies observers the list
   // of tabs has changed.
-  void ClearEntries();
+  virtual void ClearEntries() = 0;
 
   // Returns the entries, ordered with most recently closed entries at the
   // front.
-  virtual const Entries& entries() const;
+  virtual const Entries& entries() const = 0;
 
   // Restores the most recently closed entry. Does nothing if there are no
   // entries to restore. If the most recently restored entry is a tab, it is
   // added to |delegate|.
-  void RestoreMostRecentEntry(TabRestoreServiceDelegate* delegate);
+  virtual void RestoreMostRecentEntry(TabRestoreServiceDelegate* delegate) = 0;
 
   // Removes the Tab with id |id| from the list and returns it; ownership is
   // passed to the caller.
-  Tab* RemoveTabEntryById(SessionID::id_type id);
+  virtual Tab* RemoveTabEntryById(SessionID::id_type id) = 0;
 
   // Restores an entry by id. If there is no entry with an id matching |id|,
   // this does nothing. If |delegate| is NULL, this creates a new window for the
   // entry. |disposition| is respected, but the attributes (tabstrip index,
   // browser window) of the tab when it was closed will be respected if
   // disposition is UNKNOWN.
-  void RestoreEntryById(TabRestoreServiceDelegate* delegate,
-                        SessionID::id_type id,
-                        WindowOpenDisposition disposition);
+  virtual void RestoreEntryById(TabRestoreServiceDelegate* delegate,
+                                SessionID::id_type id,
+                                WindowOpenDisposition disposition) = 0;
 
   // Loads the tabs and previous session. This does nothing if the tabs
   // from the previous session have already been loaded.
-  void LoadTabsFromLastSession();
+  virtual void LoadTabsFromLastSession() = 0;
 
   // Returns true if the tab entries have been loaded.
-  bool IsLoaded() const;
+  virtual bool IsLoaded() const = 0;
 
-  // Max number of entries we'll keep around.
-  static const size_t kMaxEntries;
-
-  // Creates and add entries to |entries| for each of the windows in |windows|.
-  void CreateEntriesFromWindows(std::vector<SessionWindow*>* windows,
-                                std::vector<Entry*>* entries);
-
- protected:
-  // ProfileKeyedService:
-  virtual void Shutdown() OVERRIDE;
-
-  // BaseSessionService:
-  virtual void Save() OVERRIDE;
-
- private:
-  friend class TabRestoreServiceTest;
-  FRIEND_TEST_ALL_PREFIXES(TabRestoreServiceTest, PruneEntries);
-  FRIEND_TEST_ALL_PREFIXES(TabRestoreServiceTest, PruneIsCalled);
-
-  // Used to indicate what has loaded.
-  enum LoadState {
-    // Indicates we haven't loaded anything.
-    NOT_LOADED           = 1 << 0,
-
-    // Indicates we've asked for the last sessions and tabs but haven't gotten
-    // the result back yet.
-    LOADING              = 1 << 2,
-
-    // Indicates we finished loading the last tabs (but not necessarily the
-    // last session).
-    LOADED_LAST_TABS     = 1 << 3,
-
-    // Indicates we finished loading the last session (but not necessarily the
-    // last tabs).
-    LOADED_LAST_SESSION  = 1 << 4
-  };
-
-  // Populates the tab's navigations from the NavigationController, and its
-  // browser_id and pinned state from the browser.
-  void PopulateTab(Tab* tab,
-                   int index,
-                   TabRestoreServiceDelegate* delegate,
-                   content::NavigationController* controller);
-
-  // Notifies observers the tabs have changed.
-  void NotifyTabsChanged();
-
-  // Adds |entry| to the list of entries and takes ownership. If |prune| is true
-  // |PruneAndNotify| is invoked. If |to_front| is true the entry is added to
-  // the front, otherwise the back. Normal closes go to the front, but
-  // tab/window closes from the previous session are added to the back.
-  void AddEntry(Entry* entry, bool prune, bool to_front);
-
-  // Prunes entries_ to contain only kMaxEntries, and removes uninteresting
-  // entries.
-  void PruneEntries();
-
-  // Returns an iterator into entries_ whose id matches |id|. If |id| identifies
-  // a Window, then its iterator position will be returned. If it identifies a
-  // tab, then the iterator position of the Window in which the Tab resides is
-  // returned.
-  Entries::iterator GetEntryIteratorById(SessionID::id_type id);
-
-  // Schedules the commands for a window close.
-  void ScheduleCommandsForWindow(const Window& window);
-
-  // Schedules the commands for a tab close. |selected_index| gives the
-  // index of the selected navigation.
-  void ScheduleCommandsForTab(const Tab& tab, int selected_index);
-
-  // Creates a window close command.
-  SessionCommand* CreateWindowCommand(SessionID::id_type id,
-                                      int selected_tab_index,
-                                      int num_tabs,
-                                      base::Time timestamp);
-
-  // Creates a tab close command.
-  SessionCommand* CreateSelectedNavigationInTabCommand(
-      SessionID::id_type tab_id,
-      int32 index,
-      base::Time timestamp);
-
-  // Creates a restore command.
-  SessionCommand* CreateRestoredEntryCommand(SessionID::id_type entry_id);
-
-  // Returns the index to persist as the selected index. This is the same
-  // as |tab.current_navigation_index| unless the entry at
-  // |tab.current_navigation_index| shouldn't be persisted. Returns -1 if
-  // no valid navigation to persist.
-  int GetSelectedNavigationIndexToPersist(const Tab& tab);
-
-  // Invoked when we've loaded the session commands that identify the
-  // previously closed tabs. This creates entries, adds them to
-  // staging_entries_, and invokes LoadState.
-  void OnGotLastSessionCommands(
-      Handle handle,
-      scoped_refptr<InternalGetCommandsRequest> request);
-
-  // Populates |loaded_entries| with Entries from |request|.
-  void CreateEntriesFromCommands(
-      scoped_refptr<InternalGetCommandsRequest> request,
-      std::vector<Entry*>* loaded_entries);
-
-  // This is a helper function for RestoreEntryById() for restoring a single
-  // tab. If |delegate| is NULL, this creates a new window for the entry. This
-  // returns the TabRestoreServiceDelegate into which the tab was restored.
-  // |disposition| will be respected, but if it is UNKNOWN then the tab's
-  // original attributes will be respected instead.
-  TabRestoreServiceDelegate* RestoreTab(const Tab& tab,
-                                        TabRestoreServiceDelegate* delegate,
-                                        WindowOpenDisposition disposition);
-
-  // Returns true if |tab| has more than one navigation. If |tab| has more
-  // than one navigation |tab->current_navigation_index| is constrained based
-  // on the number of navigations.
-  static bool ValidateTab(Tab* tab);
-
-  // Validates all the tabs in a window, plus the window's active tab index.
-  static bool ValidateWindow(Window* window);
-
-  // Calls either ValidateTab or ValidateWindow as appropriate.
-  static bool ValidateEntry(Entry* entry);
-
-  // Returns true if |tab| is one we care about restoring.
-  static bool IsTabInteresting(const Tab* tab);
-
-  // Checks whether |window| is interesting --- if it only contains a single,
-  // uninteresting tab, it's not interesting.
-  static bool IsWindowInteresting(const Window* window);
-
-  // Validates and checks |entry| for interesting.
-  static bool FilterEntry(Entry* entry);
-
-  // Validates all entries in |entries|, deleting any with no navigations.
-  // This also deletes any entries beyond the max number of entries we can
-  // hold.
-  void ValidateAndDeleteEmptyEntries(std::vector<Entry*>* entries);
-
-  // Finds tab entries with the old browser_id and sets it to the new one.
-  void UpdateTabBrowserIDs(SessionID::id_type old_id,
-                           SessionID::id_type new_id);
-
-  // Callback from SessionService when we've received the windows from the
-  // previous session. This creates and add entries to |staging_entries_|
-  // and invokes LoadStateChanged. |ignored_active_window| is ignored because
-  // we don't need to restore activation.
-  void OnGotPreviousSession(Handle handle,
-                            std::vector<SessionWindow*>* windows,
-                            SessionID::id_type ignored_active_window);
-
-  // Converts a SessionWindow into a Window, returning true on success. We use 0
-  // as the timestamp here since we do not know when the window/tab was closed.
-  bool ConvertSessionWindowToWindow(
-      SessionWindow* session_window,
-      Window* window);
-
-  // Invoked when previous tabs or session is loaded. If both have finished
-  // loading the entries in staging_entries_ are added to entries_ and
-  // observers are notified.
-  void LoadStateChanged();
-
-  // Gets the current time. This uses the time_factory_ if there is one.
-  base::Time TimeNow() const;
-
-  // Set of entries. They are ordered from most to least recent.
-  Entries entries_;
-
-  // Whether we've loaded the last session.
-  int load_state_;
-
-  // Are we restoring a tab? If this is true we ignore requests to create a
-  // historical tab.
-  bool restoring_;
-
-  // The number of entries to write.
-  int entries_to_write_;
-
-  // Number of entries we've written.
-  int entries_written_;
-
-  ObserverList<TabRestoreServiceObserver> observer_list_;
-
-  // Set of delegates that we've received a BrowserClosing method for but no
-  // corresponding BrowserClosed. We cache the set of delegates closing to
-  // avoid creating historical tabs for them.
-  std::set<TabRestoreServiceDelegate*> closing_delegates_;
-
-  // Used when loading open tabs/session when recovering from a crash.
-  CancelableRequestConsumer crash_consumer_;
-
-  // Used when loading previous tabs/session.
-  CancelableRequestConsumer load_consumer_;
-
-  // Results from previously closed tabs/sessions is first added here. When
-  // the results from both us and the session restore service have finished
-  // loading LoadStateChanged is invoked, which adds these entries to
-  // entries_.
-  std::vector<Entry*> staging_entries_;
-
-  TimeFactory* time_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(TabRestoreService);
+  // Deletes the last session.
+  virtual void DeleteLastSession() = 0;
 };
 
 #endif  // CHROME_BROWSER_SESSIONS_TAB_RESTORE_SERVICE_H_