Make DownloadHistory observe manager, items

chrome/browser/history/download_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_DOWNLOAD_DATABASE_H_
 #define CHROME_BROWSER_HISTORY_DOWNLOAD_DATABASE_H_
 
 #include <set>
 #include <string>
 
 #include "base/threading/platform_thread.h"
 #include "chrome/browser/history/history_types.h"
 #include "sql/meta_table.h"
 
 class FilePath;
-
-namespace content {
 struct DownloadPersistentStoreInfo;
-}
 
 namespace sql {
 class Connection;
 }
 
 namespace history {
 
 // Maintains a table of downloads.
 class DownloadDatabase {
  public:
+  // The value of |db_handle| indicating that the associated DownloadItem is not
+  // yet persisted.
+  static const int64 kUninitializedHandle;
+
   // Must call InitDownloadTable before using any other functions.
   DownloadDatabase();
   virtual ~DownloadDatabase();
 
   int next_download_id() const { return next_id_; }
 
   // Get all the downloads from the database.
   void QueryDownloads(
-      std::vector<content::DownloadPersistentStoreInfo>* results);
+      std::vector<DownloadPersistentStoreInfo>* results);
 
   // Update the state of one download. Returns true if successful.
-  // Does not update |url|, |start_time|, |total_bytes|; uses |db_handle| only
+  // Does not update |url|, |start_time|; uses |db_handle| only
   // to select the row in the database table to update.
-  bool UpdateDownload(const content::DownloadPersistentStoreInfo& data);
-
-  // Update the path of one download. Returns true if successful.
-  bool UpdateDownloadPath(const FilePath& path, DownloadID db_handle);
+  bool UpdateDownload(const DownloadPersistentStoreInfo& data);
 
   // Fixes state of the download entries. Sometimes entries with IN_PROGRESS
   // state are not updated during browser shutdown (particularly when crashing).
   // On the next start such entries are considered canceled. This functions
   // fixes such entries.
   bool CleanUpInProgressEntries();
 
   // Create a new database entry for one download and return its primary db id.
-  int64 CreateDownload(const content::DownloadPersistentStoreInfo& info);
+  int64 CreateDownload(const DownloadPersistentStoreInfo& info);
 
-  // Remove a download from the database.
-  void RemoveDownload(DownloadID db_handle);
-
-  // Remove all completed downloads that started after |remove_begin|
-  // (inclusive) and before |remove_end|. You may use null Time values
-  // to do an unbounded delete in either direction. This function ignores
-  // all downloads that are in progress or are waiting to be cancelled.
-  bool RemoveDownloadsBetween(base::Time remove_begin, base::Time remove_end);
+  // Remove all |handles| from the database.
+  void RemoveDownloads(const std::set<int64>& handles);
 
  protected:
   // Returns the database for the functions in this interface.
   virtual sql::Connection& GetDB() = 0;
 
   // Returns the meta-table object for the functions in this interface.
   virtual sql::MetaTable& GetMetaTable() = 0;
 
   // Returns true if able to successfully rewrite the invalid values for the
   // |state| field from 3 to 4. Returns false if there was an error fixing the
   // database. See http://crbug.com/140687
   bool MigrateDownloadsState();
 
   // Creates the downloads table if needed.
   bool InitDownloadTable();
 
   // Used to quickly clear the downloads. First you would drop it, then you
   // would re-initialize it.
   bool DropDownloadTable();
 
  private:
-  // TODO(rdsmith): Remove after http://crbug.com/96627 has been resolved.
-  void CheckThread();
+  bool EnsureColumnExists(const std::string& name, const std::string& type);
 
-  bool EnsureColumnExists(const std::string& name, const std::string& type);
+  int CountDownloads();
 
   bool owning_thread_set_;
   base::PlatformThreadId owning_thread_;
 
   int next_id_;
   int next_db_handle_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadDatabase);
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_DOWNLOAD_DATABASE_H_