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// Copyright (c) 2009 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_BOOKMARKS_BOOKMARK_MODEL_OBSERVER_H_
#define CHROME_BROWSER_BOOKMARKS_BOOKMARK_MODEL_OBSERVER_H_
#pragma once

class BookmarkModel;
class BookmarkNode;

// Observer for the BookmarkModel.
class BookmarkModelObserver {
 public:
  // Invoked when the model has finished loading.
  virtual void Loaded(BookmarkModel* model) = 0;

  // Invoked from the destructor of the BookmarkModel.
  virtual void BookmarkModelBeingDeleted(BookmarkModel* model) {}

  // Invoked when a node has moved.
  virtual void BookmarkNodeMoved(BookmarkModel* model,
                                 const BookmarkNode* old_parent,
                                 int old_index,
                                 const BookmarkNode* new_parent,
                                 int new_index) = 0;

  // Invoked when a node has been added.
  virtual void BookmarkNodeAdded(BookmarkModel* model,
                                 const BookmarkNode* parent,
                                 int index) = 0;

  // Invoked when a node has been removed, the item may still be starred though.
  // |parent| the parent of the node that was removed.
  // |old_index| the index of the removed node in |parent| before it was
  // removed.
  // |node| is the node that was removed.
  virtual void BookmarkNodeRemoved(BookmarkModel* model,
                                   const BookmarkNode* parent,
                                   int old_index,
                                   const BookmarkNode* node) = 0;

  // Invoked when the title, url or favicon of a node has changed.
  virtual void BookmarkNodeChanged(BookmarkModel* model,
                                   const BookmarkNode* node) = 0;

  // Invoked when a favicon has finished loading.
  virtual void BookmarkNodeFaviconLoaded(BookmarkModel* model,
                                         const BookmarkNode* node) = 0;

  // Invoked when the children (just direct children, not descendants) of
  // |node| have been reordered in some way, such as sorted.
  virtual void BookmarkNodeChildrenReordered(BookmarkModel* model,
                                             const BookmarkNode* node) = 0;

  // Invoked before a batch import begins.  This tells UI intensive observers
  // to wait until the updates finish to update themselves.
  // These methods should only be used for imports. Observers should still
  // respond to BookmarkNodeRemoved immediately, to avoid holding onto
  // stale node pointers.
  virtual void BookmarkImportBeginning(BookmarkModel* model) {}

  // Invoked after a batch import finishes.  This tells observers to update
  // themselves if they were waiting for the update to finish.
  virtual void BookmarkImportEnding(BookmarkModel* model) {}

 protected:
  virtual ~BookmarkModelObserver() {}
};

#endif  // CHROME_BROWSER_BOOKMARKS_BOOKMARK_MODEL_OBSERVER_H_