1// Copyright (c) 2011 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// This class implements a simplified and much stripped down version of
6// Chrome's app/resource_bundle machinery. It notably avoids unwanted
7// dependencies on things like Skia.
8//
9
10#ifndef CHROME_FRAME_SIMPLE_RESOURCE_LOADER_H_
11#define CHROME_FRAME_SIMPLE_RESOURCE_LOADER_H_
12
13#include <windows.h>
14#include <string>
15#include <vector>
16
17#include "base/files/file_path.h"
18#include "base/gtest_prod_util.h"
19#include "base/memory/singleton.h"
20
21namespace ui {
22class DataPack;
23}  // namespace ui
24
25class SimpleResourceLoader {
26 public:
27
28  static SimpleResourceLoader* GetInstance();
29
30  // Returns the language tag for the active language.
31  static std::wstring GetLanguage();
32
33  // Helper method to return the string resource identified by message_id
34  // from the currently loaded locale dll.
35  static std::wstring Get(int message_id);
36
37  // Retrieves the HINSTANCE of the loaded module handle. May be NULL if a
38  // resource DLL could not be loaded.
39  HMODULE GetResourceModuleHandle();
40
41  // Retrieves the preferred languages for the current thread, adding them to
42  // |language_tags|.
43  static void GetPreferredLanguages(std::vector<std::wstring>* language_tags);
44
45  // Populates |locales_path| with the path to the "Locales" directory.
46  static void DetermineLocalesDirectory(base::FilePath* locales_path);
47
48  // Returns false if |language_tag| is malformed.
49  static bool IsValidLanguageTag(const std::wstring& language_tag);
50
51 private:
52  SimpleResourceLoader();
53  ~SimpleResourceLoader();
54
55  // Finds the most-preferred resource dll and language pack for the laguages
56  // in |language_tags|
57  // in |locales_path|.
58  //
59  // Returns true on success with a handle to the DLL that was loaded in
60  // |dll_handle|, the data pack in |data_pack| and the locale language in
61  // the |language| parameter.
62  static bool LoadLocalePack(const std::vector<std::wstring>& language_tags,
63                             const base::FilePath& locales_path,
64                             HMODULE* dll_handle,
65                             ui::DataPack** data_pack,
66                             std::wstring* language);
67
68  // Returns the string resource identified by message_id from the currently
69  // loaded locale dll.
70  std::wstring GetLocalizedResource(int message_id);
71
72  friend struct DefaultSingletonTraits<SimpleResourceLoader>;
73
74  FRIEND_TEST_ALL_PREFIXES(SimpleResourceLoaderTest, LoadLocaleDll);
75
76  std::wstring language_;
77  ui::DataPack* data_pack_;
78
79  HINSTANCE locale_dll_handle_;
80};
81
82#endif  // CHROME_FRAME_SIMPLE_RESOURCE_LOADER_H_
83