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 namespace base {
  17 template <typename T> struct DefaultSingletonTraits;
  18 }
  19
  20 class PrefService;
  21
  22 namespace translate {
  23
  24 // Manages the downloaded resources for Translate, such as the translate script
  25 // and the language list.
  26 class TranslateDownloadManager {
  27  public:
  28   // Returns the singleton instance.
  29   static TranslateDownloadManager* GetInstance();
  30
  31   // The request context used to download the resources.
  32   // Should be set before this class can be used.
  33   net::URLRequestContextGetter* request_context() {
  34     return request_context_.get();
  35   }
  36   void set_request_context(net::URLRequestContextGetter* context) {
  37       request_context_ = context;
  38   }
  39
  40   // The application locale.
  41   // Should be set before this class can be used.
  42   const std::string& application_locale() { return application_locale_; }
  43   void set_application_locale(const std::string& locale) {
  44     application_locale_ = locale;
  45   }
  46
  47   // The language list.
  48   TranslateLanguageList* language_list() { return language_list_.get(); }
  49
  50   // The translate script.
  51   TranslateScript* script() { return script_.get(); }
  52
  53   // Let the caller decide if and when we should fetch the language list from
  54   // the translate server. This is a NOOP if switches::kDisableTranslate is set
  55   // or if prefs::kEnableTranslate is set to false.
  56   static void RequestLanguageList(PrefService* prefs);
  57
  58   // Fetches the language list from the translate server.
  59   static void RequestLanguageList();
  60
  61   // Fills |languages| with the list of languages that the translate server can
  62   // translate to and from.
  63   static void GetSupportedLanguages(std::vector<std::string>* languages);
  64
  65   // Returns the last-updated time when Chrome received a language list from a
  66   // Translate server. Returns null time if Chrome hasn't received any lists.
  67   static base::Time GetSupportedLanguagesLastUpdated();
  68
  69   // Returns the language code that can be used with the Translate method for a
  70   // specified |language|. (ex. GetLanguageCode("en-US") will return "en", and
  71   // GetLanguageCode("zh-CN") returns "zh-CN")
  72   static std::string GetLanguageCode(const std::string& language);
  73
  74   // Returns true if |language| is supported by the translation server.
  75   static bool IsSupportedLanguage(const std::string& language);
  76
  77   // Returns true if |language| is supported by the translation server as an
  78   // alpha language.
  79   static bool IsAlphaLanguage(const std::string& language);
  80
  81   // Must be called to shut Translate down. Cancels any pending fetches.
  82   void Shutdown();
  83
  84   // Clears the translate script, so it will be fetched next time we translate.
  85   void ClearTranslateScriptForTesting();
  86
  87   // Resets to its initial state as if newly created.
  88   void ResetForTesting();
  89
  90   // Used by unit-tests to override some defaults:
  91   // Delay after which the translate script is fetched again from the
  92   // translation server.
  93   void SetTranslateScriptExpirationDelay(int delay_ms);
  94
  95  private:
  96   friend struct base::DefaultSingletonTraits<TranslateDownloadManager>;
  97   TranslateDownloadManager();
  98   virtual ~TranslateDownloadManager();
  99
 100   scoped_ptr<TranslateLanguageList> language_list_;
 101
 102   // An instance of TranslateScript which manages JavaScript source for
 103   // Translate.
 104   scoped_ptr<TranslateScript> script_;
 105
 106   std::string application_locale_;
 107   scoped_refptr<net::URLRequestContextGetter> request_context_;
 108 };
 109
 110 }  // namespace translate
 111
 112 #endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_DOWNLOAD_MANAGER_H_