components/translate/core/browser/translate_download_manager.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_CORE_BROWSER_TRANSLATE_DOWNLOAD_MANAGER_H_
   6 #define COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_DOWNLOAD_MANAGER_H_
   7
   8 #include <string>
   9
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "components/translate/core/browser/translate_language_list.h"
  13 #include "components/translate/core/browser/translate_script.h"
  14 #include "net/url_request/url_request_context_getter.h"
  15
  16 template <typename T> struct DefaultSingletonTraits;
  17
  18 class PrefService;
  19
  20 namespace translate {
  21
  22 // Manages the downloaded resources for Translate, such as the translate script
  23 // and the language list.
  24 class TranslateDownloadManager {
  25  public:
  26   // Returns the singleton instance.
  27   static TranslateDownloadManager* GetInstance();
  28
  29   // The request context used to download the resources.
  30   // Should be set before this class can be used.
  31   net::URLRequestContextGetter* request_context() {
  32     return request_context_.get();
  33   }
  34   void set_request_context(net::URLRequestContextGetter* context) {
  35       request_context_ = context;
  36   }
  37
  38   // The application locale.
  39   // Should be set before this class can be used.
  40   const std::string& application_locale() { return application_locale_; }
  41   void set_application_locale(const std::string& locale) {
  42     application_locale_ = locale;
  43   }
  44
  45   // The language list.
  46   TranslateLanguageList* language_list() { return language_list_.get(); }
  47
  48   // The translate script.
  49   TranslateScript* script() { return script_.get(); }
  50
  51   // Let the caller decide if and when we should fetch the language list from
  52   // the translate server. This is a NOOP if switches::kDisableTranslate is set
  53   // or if prefs::kEnableTranslate is set to false.
  54   static void RequestLanguageList(PrefService* prefs);
  55
  56   // Fetches the language list from the translate server.
  57   static void RequestLanguageList();
  58
  59   // Fills |languages| with the list of languages that the translate server can
  60   // translate to and from.
  61   static void GetSupportedLanguages(std::vector<std::string>* languages);
  62
  63   // Returns the last-updated time when Chrome received a language list from a
  64   // Translate server. Returns null time if Chrome hasn't received any lists.
  65   static base::Time GetSupportedLanguagesLastUpdated();
  66
  67   // Returns the language code that can be used with the Translate method for a
  68   // specified |language|. (ex. GetLanguageCode("en-US") will return "en", and
  69   // GetLanguageCode("zh-CN") returns "zh-CN")
  70   static std::string GetLanguageCode(const std::string& language);
  71
  72   // Returns true if |language| is supported by the translation server.
  73   static bool IsSupportedLanguage(const std::string& language);
  74
  75   // Returns true if |language| is supported by the translation server as an
  76   // alpha language.
  77   static bool IsAlphaLanguage(const std::string& language);
  78
  79   // Must be called to shut Translate down. Cancels any pending fetches.
  80   void Shutdown();
  81
  82   // Clears the translate script, so it will be fetched next time we translate.
  83   void ClearTranslateScriptForTesting();
  84
  85   // Resets to its initial state as if newly created.
  86   void ResetForTesting();
  87
  88   // Used by unit-tests to override some defaults:
  89   // Delay after which the translate script is fetched again from the
  90   // translation server.
  91   void SetTranslateScriptExpirationDelay(int delay_ms);
  92
  93  private:
  94   friend struct DefaultSingletonTraits<TranslateDownloadManager>;
  95   TranslateDownloadManager();
  96   virtual ~TranslateDownloadManager();
  97
  98   scoped_ptr<TranslateLanguageList> language_list_;
  99
 100   // An instance of TranslateScript which manages JavaScript source for
 101   // Translate.
 102   scoped_ptr<TranslateScript> script_;
 103
 104   std::string application_locale_;
 105   scoped_refptr<net::URLRequestContextGetter> request_context_;
 106 };
 107
 108 }  // namespace translate
 109
 110 #endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_DOWNLOAD_MANAGER_H_