components/translate/ios/browser/language_detection_controller.h

   1 // Copyright 2014 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 COMPONENTS_TRANSLATE_IOS_BROWSER_LANGUAGE_DETECTION_CONTROLLER_H_
   6 #define COMPONENTS_TRANSLATE_IOS_BROWSER_LANGUAGE_DETECTION_CONTROLLER_H_
   7
   8 #include <string>
   9
  10 #include "base/callback_list.h"
  11 #include "base/gtest_prod_util.h"
  12 #include "base/mac/scoped_nsobject.h"
  13 #include "base/macros.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "base/prefs/pref_member.h"
  16 #include "base/strings/string16.h"
  17 #include "ios/web/public/web_state/web_state_observer.h"
  18
  19 class GURL;
  20 @class JsLanguageDetectionManager;
  21 class PrefService;
  22
  23 namespace base {
  24 class DictionaryValue;
  25 }
  26
  27 namespace web {
  28 class WebState;
  29 }
  30
  31 namespace translate {
  32
  33 class LanguageDetectionController : public web::WebStateObserver {
  34  public:
  35   // Language detection details, passed to language detection callbacks.
  36   struct DetectionDetails {
  37     // The language detected by the content (Content-Language).
  38     std::string content_language;
  39
  40     // The language written in the lang attribute of the html element.
  41     std::string html_root_language;
  42
  43     // The adopted language.
  44     std::string adopted_language;
  45   };
  46
  47   LanguageDetectionController(web::WebState* web_state,
  48                               JsLanguageDetectionManager* manager,
  49                               PrefService* prefs);
  50   ~LanguageDetectionController() override;
  51
  52   // Callback types for language detection events.
  53   typedef base::Callback<void(const DetectionDetails&)> Callback;
  54   typedef base::CallbackList<void(const DetectionDetails&)> CallbackList;
  55
  56   // Registers a callback for language detection events.
  57   scoped_ptr<CallbackList::Subscription> RegisterLanguageDetectionCallback(
  58       const Callback& callback);
  59
  60  private:
  61   FRIEND_TEST_ALL_PREFIXES(LanguageDetectionControllerTest, OnTextCaptured);
  62
  63   // Starts the page language detection and initiates the translation process.
  64   void StartLanguageDetection();
  65
  66   // Handles the "languageDetection.textCaptured" javascript command.
  67   // |interacting| is true if the user is currently interacting with the page.
  68   bool OnTextCaptured(const base::DictionaryValue& value,
  69                       const GURL& url,
  70                       bool interacting);
  71
  72   // Completion handler used to retrieve the text buffered by the
  73   // JsLanguageDetectionManager.
  74   void OnTextRetrieved(const std::string& http_content_language,
  75                        const std::string& html_lang,
  76                        const base::string16& text);
  77
  78   // web::WebStateObserver implementation:
  79   void PageLoaded(
  80       web::PageLoadCompletionStatus load_completion_status) override;
  81   void UrlHashChanged() override;
  82   void HistoryStateChanged() override;
  83   void WebStateDestroyed() override;
  84
  85   CallbackList language_detection_callbacks_;
  86   base::scoped_nsobject<JsLanguageDetectionManager> js_manager_;
  87   BooleanPrefMember translate_enabled_;
  88   base::WeakPtrFactory<LanguageDetectionController> weak_method_factory_;
  89
  90   DISALLOW_COPY_AND_ASSIGN(LanguageDetectionController);
  91 };
  92
  93 }  // namespace translate
  94
  95 #endif  // COMPONENTS_TRANSLATE_IOS_BROWSER_LANGUAGE_DETECTION_CONTROLLER_H_