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#ifndef CHROME_BROWSER_TAB_CONTENTS_LANGUAGE_STATE_H_
6#define CHROME_BROWSER_TAB_CONTENTS_LANGUAGE_STATE_H_
7#pragma once
8
9#include <string>
10
11#include "base/basictypes.h"
12#include "content/browser/tab_contents/navigation_controller.h"
13
14// This class holds the language state of the current page.
15// There is one LanguageState instance per TabContents.
16// It is used to determine when navigating to a new page whether it should
17// automatically be translated.
18// This auto-translate behavior is the expected behavior when:
19// - user is on page in language A that they had translated to language B.
20// - user clicks a link in that page that takes them to a page also in language
21//   A.
22
23class LanguageState {
24 public:
25  explicit LanguageState(NavigationController* nav_controller);
26  ~LanguageState();
27
28  // Should be called when the page did a new navigation (whether it is a main
29  // frame or sub-frame navigation).
30  void DidNavigate(const NavigationController::LoadCommittedDetails& details);
31
32  // Should be called when the language of the page has been determined.
33  // |page_translatable| when false indicates that the browser should not offer
34  // to translate the page.
35  void LanguageDetermined(const std::string& page_language,
36                          bool page_translatable);
37
38  // Returns the language the current page should be translated to, based on the
39  // previous page languages and the transition.  This should be called after
40  // the language page has been determined.
41  // Returns an empty string if the page should not be auto-translated.
42  std::string AutoTranslateTo() const;
43
44  // Returns true if the current page in the associated tab has been translated.
45  bool IsPageTranslated() const { return original_lang_ != current_lang_; }
46
47  const std::string& original_language() const { return original_lang_; }
48
49  void set_current_language(const std::string& language) {
50    current_lang_ = language;
51  }
52  const std::string& current_language() const { return current_lang_; }
53
54  bool page_translatable() const { return page_translatable_; }
55
56  // Whether the page is currently in the process of being translated.
57  bool translation_pending() const { return translation_pending_; }
58  void set_translation_pending(bool value) { translation_pending_ = value; }
59
60  // Whether the user has already declined to translate the page.
61  bool translation_declined() const { return translation_declined_; }
62  void set_translation_declined(bool value) { translation_declined_ = value; }
63
64  // Whether the current page was navigated through an in-page (fragment)
65  // navigation.
66  bool in_page_navigation() const { return in_page_navigation_; }
67
68 private:
69  // The languages this page is in. Note that current_lang_ is different from
70  // original_lang_ when the page has been translated.
71  // Note that these might be empty if the page language has not been determined
72  // yet.
73  std::string original_lang_;
74  std::string current_lang_;
75
76  // Same as above but for the previous page.
77  std::string prev_original_lang_;
78  std::string prev_current_lang_;
79
80  // The navigation controller of the tab we are associated with.
81  NavigationController* navigation_controller_;
82
83  // Whether it is OK to offer to translate the page.  Some pages explictly
84  // specify that they should not be translated by the browser (this is the case
85  // for GMail for example, which provides its own translation features).
86  bool page_translatable_;
87
88  // Whether a translation is currently pending (TabContents waiting for the
89  // PAGE_TRANSLATED notification).  This is needed to avoid sending duplicate
90  // translate requests to a page.  TranslateManager initiates translations
91  // when it received the LANGUAGE_DETERMINED notification.  This is sent by
92  // the renderer with the page contents, every time the load stops for the
93  // main frame, so we may get several.
94  // TODO(jcampan): make the renderer send the language just once per navigation
95  //                then we can get rid of that state.
96  bool translation_pending_;
97
98  // Whether the user has declined to translate the page (by closing the infobar
99  // for example).  This is necessary as a new infobar could be shown if a new
100  // load happens in the page after the user closed the infobar.
101  bool translation_declined_;
102
103  // Whether the current navigation is a fragment navigation (in page).
104  bool in_page_navigation_;
105
106  DISALLOW_COPY_AND_ASSIGN(LanguageState);
107};
108
109#endif  // CHROME_BROWSER_TAB_CONTENTS_LANGUAGE_STATE_H_
110