input_method_util.h revision 5d1f7b1de12d16ceb2c938c56701a3e8bfa558f7 
1// Copyright (c) 2012 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 CHROME_BROWSER_CHROMEOS_INPUT_METHOD_INPUT_METHOD_UTIL_H_
6#define CHROME_BROWSER_CHROMEOS_INPUT_METHOD_INPUT_METHOD_UTIL_H_
7
8#include <cstddef>
9#include <map>
10#include <string>
11#include <vector>
12
13#include "base/containers/hash_tables.h"
14#include "base/memory/scoped_ptr.h"
15#include "base/strings/string16.h"
16#include "base/threading/thread_checker.h"
17#include "chromeos/ime/input_method_descriptor.h"
18
19namespace chromeos {
20namespace input_method {
21
22class InputMethodDelegate;
23
24enum InputMethodType {
25  kKeyboardLayoutsOnly,
26  kAllInputMethods,
27};
28
29// A class which provides miscellaneous input method utility functions.
30class InputMethodUtil {
31 public:
32  // |supported_input_methods| is a list of all input methods supported,
33  // including ones not active. The list is used to initialize member variables
34  // in this class.
35  InputMethodUtil(InputMethodDelegate* delegate,
36                  scoped_ptr<InputMethodDescriptors> supported_input_methods);
37  ~InputMethodUtil();
38
39  // Converts a string sent from IBus IME engines, which is written in English,
40  // into Chrome's string ID, then pulls internationalized resource string from
41  // the resource bundle and returns it. These functions are not thread-safe.
42  // Non-UI threads are not allowed to call them.
43  base::string16 TranslateString(const std::string& english_string) const;
44
45  // Converts an input method ID to a language code of the IME. Returns "Eng"
46  // when |input_method_id| is unknown.
47  // Example: "hangul" => "ko"
48  std::string GetLanguageCodeFromInputMethodId(
49      const std::string& input_method_id) const;
50
51  // Converts an input method ID to a display name of the IME. Returns
52  // an empty strng when |input_method_id| is unknown.
53  // Examples: "pinyin" => "Pinyin"
54  std::string GetInputMethodDisplayNameFromId(
55      const std::string& input_method_id) const;
56
57  base::string16 GetInputMethodShortName(
58      const InputMethodDescriptor& input_method) const;
59  base::string16 GetInputMethodMediumName(
60      const InputMethodDescriptor& input_method) const;
61  base::string16 GetInputMethodLongName(
62      const InputMethodDescriptor& input_method) const;
63
64  // Converts an input method ID to an input method descriptor. Returns NULL
65  // when |input_method_id| is unknown.
66  // Example: "pinyin" => { id: "pinyin", display_name: "Pinyin",
67  //                        keyboard_layout: "us", language_code: "zh" }
68  const InputMethodDescriptor* GetInputMethodDescriptorFromId(
69      const std::string& input_method_id) const;
70
71  // Gets input method IDs that belong to |language_code|.
72  // If |type| is |kKeyboardLayoutsOnly|, the function does not return input
73  // methods that are not for keybord layout switching. Returns true on success.
74  // Note that the function might return false or |language_code| is unknown.
75  //
76  // The retured input method IDs are sorted by populalirty per
77  // chromeos/platform/assets/input_methods/whitelist.txt.
78  bool GetInputMethodIdsFromLanguageCode(
79      const std::string& language_code,
80      InputMethodType type,
81      std::vector<std::string>* out_input_method_ids) const;
82
83  // Gets the input method IDs suitable for the first user login, based on
84  // the given language code (UI language), and the descriptor of the
85  // current input method.
86  void GetFirstLoginInputMethodIds(
87      const std::string& language_code,
88      const InputMethodDescriptor& current_input_method,
89      std::vector<std::string>* out_input_method_ids) const;
90
91  // Gets the language codes associated with the given input method IDs.
92  // The returned language codes won't have duplicates.
93  void GetLanguageCodesFromInputMethodIds(
94      const std::vector<std::string>& input_method_ids,
95      std::vector<std::string>* out_language_codes) const;
96
97  // Gets first input method associated with the language.
98  // Returns empty string on error.
99  std::string GetLanguageDefaultInputMethodId(const std::string& language_code);
100
101  // Updates the internal cache of hardware layouts.
102  void UpdateHardwareLayoutCache();
103
104  // Set hardware keyboard layout for testing purpose. This is for simulating
105  // "keyboard_layout" entry in VPD values.
106  void SetHardwareKeyboardLayoutForTesting(const std::string& layout);
107
108  // Fills the input method IDs of the hardware keyboard. e.g. "xkb:us::eng"
109  // for US Qwerty keyboard or "xkb:ru::rus" for Russian keyboard.
110  const std::vector<std::string>& GetHardwareInputMethodIds();
111
112  // Returns the login-allowed input method ID of the hardware keyboard, e.g.
113  // "xkb:us::eng" but not include non-login keyboard like "xkb:ru::rus". Please
114  // note that this is not a subset of returned value of
115  // GetHardwareInputMethodIds. If GetHardwareInputMethodIds returns only
116  // non-login keyboard, this function will returns "xkb:us::eng" as the
117  // fallback keyboard.
118  const std::vector<std::string>& GetHardwareLoginInputMethodIds();
119
120  // Returns true if given input method can be used to input login data.
121  bool IsLoginKeyboard(const std::string& input_method_id) const;
122
123  // Returns true if the given input method id is supported.
124  bool IsValidInputMethodId(const std::string& input_method_id) const;
125
126  // Returns true if the given input method id is for a keyboard layout.
127  static bool IsKeyboardLayout(const std::string& input_method_id);
128
129  // Sets the list of component extension IMEs.
130  void SetComponentExtensions(const InputMethodDescriptors& imes);
131
132  // Returns the fallback input method descriptor (the very basic US
133  // keyboard). This function is mostly used for testing, but may be used
134  // as the fallback, when there is no other choice.
135  static InputMethodDescriptor GetFallbackInputMethodDescriptor();
136
137 protected:
138  // protected: for unit testing as well.
139  bool GetInputMethodIdsFromLanguageCodeInternal(
140      const std::multimap<std::string, std::string>& language_code_to_ids,
141      const std::string& normalized_language_code,
142      InputMethodType type,
143      std::vector<std::string>* out_input_method_ids) const;
144
145  // protected: for unit testing as well.
146  void ReloadInternalMaps();
147
148  // All input methods that are supported, including ones not active.
149  // protected: for testing.
150  scoped_ptr<InputMethodDescriptors> supported_input_methods_;
151
152  // Gets the keyboard layout name from the given input method ID.
153  // If the ID is invalid, an empty string will be returned.
154  // This function only supports xkb layouts.
155  //
156  // Examples:
157  //
158  // "xkb:us::eng"       => "us"
159  // "xkb:us:dvorak:eng" => "us(dvorak)"
160  // "xkb:gb::eng"       => "gb"
161  // "pinyin"            => "us" (because Pinyin uses US keyboard layout)
162  std::string GetKeyboardLayoutName(const std::string& input_method_id) const;
163
164 private:
165  bool TranslateStringInternal(const std::string& english_string,
166                               base::string16 *out_string) const;
167
168  // Map from language code to associated input method IDs, etc.
169  typedef std::multimap<std::string, std::string> LanguageCodeToIdsMap;
170  // Map from input method ID to associated input method descriptor.
171  typedef std::map<
172    std::string, InputMethodDescriptor> InputMethodIdToDescriptorMap;
173  // Map from XKB layout ID to associated input method descriptor.
174  typedef std::map<std::string, InputMethodDescriptor> XkbIdToDescriptorMap;
175  // Map from component extention IME id to associated input method descriptor.
176  typedef std::map<std::string, InputMethodDescriptor> ComponentExtIMEMap;
177
178  LanguageCodeToIdsMap language_code_to_ids_;
179  std::map<std::string, std::string> id_to_language_code_;
180  InputMethodIdToDescriptorMap id_to_descriptor_;
181  XkbIdToDescriptorMap xkb_id_to_descriptor_;
182  ComponentExtIMEMap component_extension_ime_id_to_descriptor_;
183
184  typedef base::hash_map<std::string, int> HashType;
185  HashType english_to_resource_id_;
186
187  InputMethodDelegate* delegate_;
188
189  base::ThreadChecker thread_checker_;
190  std::vector<std::string> hardware_layouts_;
191  std::vector<std::string> hardware_login_layouts_;
192
193  DISALLOW_COPY_AND_ASSIGN(InputMethodUtil);
194};
195
196}  // namespace input_method
197}  // namespace chromeos
198
199#endif  // CHROME_BROWSER_CHROMEOS_INPUT_METHOD_INPUT_METHOD_UTIL_H_
200