text: // Copyright 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.
  
  #ifndef COMPONENTS_SYNC_SESSIONS_OPEN_TABS_UI_DELEGATE_H_
  #define COMPONENTS_SYNC_SESSIONS_OPEN_TABS_UI_DELEGATE_H_
  
  #include <string>
  #include <vector>
  
  #include "base/memory/ref_counted.h"
  #include "base/memory/ref_counted_memory.h"
  #include "components/sessions/core/session_id.h"
  #include "components/sessions/core/session_types.h"
  #include "components/sync_sessions/synced_session.h"
  
  namespace sync_sessions {
  
  class OpenTabsUIDelegate {
   public:
    // If a valid favicon for the page at |url| is found, fills |favicon_png| with
    // the png-encoded image and returns true. Else, returns false.
    virtual bool GetSyncedFaviconForPageURL(
        const std::string& pageurl,
        scoped_refptr<base::RefCountedMemory>* favicon_png) const = 0;
  
    // Builds a list of all foreign sessions, ordered from most recent to least
    // recent. Caller does NOT own SyncedSession objects.
    // Returns true if foreign sessions were found, false otherwise.
    virtual bool GetAllForeignSessions(
        std::vector<const SyncedSession*>* sessions) = 0;
  
    // Looks up the foreign tab identified by |tab_id| and belonging to foreign
    // session |tag|. Caller does NOT own the SessionTab object.
    // Returns true if the foreign session and tab were found, false otherwise.
    virtual bool GetForeignTab(const std::string& tag,
                               SessionID::id_type tab_id,
                               const sessions::SessionTab** tab) = 0;
  
    // Delete a foreign session and all its sync data.
    virtual void DeleteForeignSession(const std::string& tag) = 0;
  
    // Loads all windows for foreign session with session tag |tag|. Caller does
    // NOT own SessionWindow objects.
    // Returns true if the foreign session was found, false otherwise.
    virtual bool GetForeignSession(
        const std::string& tag,
        std::vector<const sessions::SessionWindow*>* windows) = 0;
  
    // Loads all tabs for a foreign session, ignoring window grouping, and
    // ordering by recency (most recent to least recent). Will automatically
    // prune those tabs that are not syncable or are the NTP. Caller does NOT own
    // SessionTab objects.
    // Returns true if the foreign session was found, false otherwise.
    virtual bool GetForeignSessionTabs(
        const std::string& tag,
        std::vector<const sessions::SessionTab*>* tabs) = 0;
  
    // Sets |*local| to point to the sessions sync representation of the
    // local machine.
    virtual bool GetLocalSession(const SyncedSession** local) = 0;
  
   protected:
    virtual ~OpenTabsUIDelegate();
  };
  
  }  // namespace sync_sessions
  
  #endif  // COMPONENTS_SYNC_SESSIONS_OPEN_TABS_UI_DELEGATE_H_
  