Componentize TopSites, TopSitesBackend, TopSitesDatabase

chrome/browser/history/top_sites_database.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_HISTORY_TOP_SITES_DATABASE_H_
-#define CHROME_BROWSER_HISTORY_TOP_SITES_DATABASE_H_
-
-#include <map>
-#include <string>
-
-#include "base/gtest_prod_util.h"
-#include "components/history/core/browser/history_types.h"
-#include "sql/meta_table.h"
-
-namespace base {
-class FilePath;
-}
-
-namespace sql {
-class Connection;
-}
-
-namespace history {
-
-class TopSitesDatabase {
- public:
-  TopSitesDatabase();
-  ~TopSitesDatabase();
-
-  // Must be called after creation but before any other methods are called.
-  // Returns true on success. If false, no other functions should be called.
-  bool Init(const base::FilePath& db_name);
-
-  // Thumbnails ----------------------------------------------------------------
-
-  // Returns a list of all URLs currently in the table.
-  // WARNING: clears both input arguments.
-  void GetPageThumbnails(MostVisitedURLList* urls,
-                         std::map<GURL, Images>* thumbnails);
-
-  // Set a thumbnail for a URL. |url_rank| is the position of the URL
-  // in the list of TopURLs, zero-based.
-  // If the URL is not in the table, add it. If it is, replace its
-  // thumbnail and rank. Shift the ranks of other URLs if necessary.
-  void SetPageThumbnail(const MostVisitedURL& url,
-                        int new_rank,
-                        const Images& thumbnail);
-
-  // Sets the rank for a given URL. The URL must be in the database.
-  // Use SetPageThumbnail if it's not.
-  void UpdatePageRank(const MostVisitedURL& url, int new_rank);
-
-  // Get a thumbnail for a given page. Returns true iff we have the thumbnail.
-  bool GetPageThumbnail(const GURL& url, Images* thumbnail);
-
-  // Remove the record for this URL. Returns true iff removed successfully.
-  bool RemoveURL(const MostVisitedURL& url);
-
- private:
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version1);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version2);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version3);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery1);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery2);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery3);
-  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, AddRemoveEditThumbnails);
-
-  // Rank of all URLs that are forced and therefore cannot be automatically
-  // evicted.
-  static const int kRankOfForcedURL;
-
-  // Rank used to indicate that a URL is not stored in the database.
-  static const int kRankOfNonExistingURL;
-
-  // Upgrades the thumbnail table to version 3, returning true if the
-  // upgrade was successful.
-  bool UpgradeToVersion3();
-
-  // Adds a new URL to the database.
-  void AddPageThumbnail(const MostVisitedURL& url,
-                        int new_rank,
-                        const Images& thumbnail);
-
-  // Sets the page rank. Should be called within an open transaction.
-  void UpdatePageRankNoTransaction(const MostVisitedURL& url, int new_rank);
-
-  // Updates thumbnail of a URL that's already in the database.
-  // Returns true if the database query succeeds.
-  bool UpdatePageThumbnail(const MostVisitedURL& url,
-                           const Images& thumbnail);
-
-  // Returns |url|'s current rank or kRankOfNonExistingURL if not present.
-  int GetURLRank(const MostVisitedURL& url);
-
-  // Helper function to implement internals of Init().  This allows
-  // Init() to retry in case of failure, since some failures will
-  // invoke recovery code.
-  bool InitImpl(const base::FilePath& db_name);
-
-  sql::Connection* CreateDB(const base::FilePath& db_name);
-
-  scoped_ptr<sql::Connection> db_;
-  sql::MetaTable meta_table_;
-
-  DISALLOW_COPY_AND_ASSIGN(TopSitesDatabase);
-};
-
-}  // namespace history
-
-#endif  // CHROME_BROWSER_HISTORY_TOP_SITES_DATABASE_H_