ui/app_list/search/history_data_store.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_APP_LIST_SEARCH_HISTORY_DATA_STORE_H_
   6 #define UI_APP_LIST_SEARCH_HISTORY_DATA_STORE_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback_forward.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "ui/app_list/app_list_export.h"
  16 #include "ui/app_list/search/dictionary_data_store.h"
  17 #include "ui/app_list/search/history_data.h"
  18
  19 namespace base {
  20 class DictionaryValue;
  21 class SequencedTaskRunner;
  22 }
  23
  24 namespace app_list {
  25
  26 namespace test {
  27 class HistoryDataStoreTest;
  28 }
  29
  30 // A simple json store to persist HistoryData.
  31 class APP_LIST_EXPORT HistoryDataStore
  32     : public base::RefCountedThreadSafe<HistoryDataStore> {
  33  public:
  34   typedef base::Callback<void(scoped_ptr<HistoryData::Associations>)>
  35       OnLoadedCallback;
  36
  37   // A data store with no storage backend.
  38   HistoryDataStore();
  39
  40   // |data_store| stores the history into the file.
  41   explicit HistoryDataStore(scoped_refptr<DictionaryDataStore> data_store);
  42
  43   // Flushes pending writes. |on_flushed| is invoked when disk write is
  44   // finished.
  45   void Flush(const DictionaryDataStore::OnFlushedCallback& on_flushed);
  46
  47   // Reads the persisted data from disk asynchronously. |on_read| is called
  48   // with the loaded and parsed data. If there is an error, |on_read| is called
  49   // without data.
  50   void Load(const OnLoadedCallback& on_loaded);
  51
  52   // Incremental changes allowed on the data store.
  53   void SetPrimary(const std::string& query, const std::string& result);
  54   void SetSecondary(const std::string& query,
  55                     const HistoryData::SecondaryDeque& results);
  56   void SetUpdateTime(const std::string& query, const base::Time& update_time);
  57   void Delete(const std::string& query);
  58
  59  private:
  60   friend class base::RefCountedThreadSafe<HistoryDataStore>;
  61   friend class app_list::test::HistoryDataStoreTest;
  62
  63   virtual ~HistoryDataStore();
  64
  65   void Init(base::DictionaryValue* cached_dict);
  66
  67   // Gets the dictionary for "associations" key.
  68   base::DictionaryValue* GetAssociationDict();
  69
  70   // Gets entry dictionary for given |query|. Creates one if necessary.
  71   base::DictionaryValue* GetEntryDict(const std::string& query);
  72
  73   void OnDictionaryLoadedCallback(OnLoadedCallback callback,
  74                                   scoped_ptr<base::DictionaryValue> dict);
  75
  76   // |cached_dict_| and |data_store_| is mutually exclusive. |data_store_| is
  77   // used if it's backed by a file storage, otherwise |cache_dict_| keeps
  78   // on-memory data.
  79   scoped_ptr<base::DictionaryValue> cached_dict_;
  80   scoped_refptr<DictionaryDataStore> data_store_;
  81
  82   DISALLOW_COPY_AND_ASSIGN(HistoryDataStore);
  83 };
  84
  85 }  // namespace app_list
  86
  87 #endif  // UI_APP_LIST_SEARCH_HISTORY_DATA_STORE_H_