Implement langageSettingsPrivate API.

chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc

Index: chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
diff --git a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
index ea03265a38f10b9956ef296fec17f35290b86010..696ef28a85ea41f2a114b8b93a4632b619722daa 100644
--- a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
+++ b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.cc
@@ -4,8 +4,31 @@
 
 #include "chrome/browser/extensions/api/language_settings_private/language_settings_private_api.h"
 
+#include <map>
+#include <string>
+#include <unordered_set>
+#include <utility>
+#include <vector>
+
+#include "base/i18n/rtl.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string16.h"
+#include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/extensions/api/language_settings_private/language_settings_private_delegate.h"
+#include "chrome/browser/extensions/api/language_settings_private/language_settings_private_delegate_factory.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/spellchecker/spellcheck_factory.h"
+#include "chrome/browser/spellchecker/spellcheck_service.h"
+#include "chrome/browser/translate/chrome_translate_client.h"
+#include "chrome/browser/translate/translate_service.h"
 #include "chrome/common/extensions/api/language_settings_private.h"
+#include "chrome/common/spellcheck_common.h"
+#include "components/translate/core/browser/translate_download_manager.h"
+#include "third_party/icu/source/i18n/unicode/coll.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/l10n/l10n_util_collator.h"
 
 namespace extensions {
 
@@ -21,11 +44,88 @@ LanguageSettingsPrivateGetLanguageListFunction::
 
 ExtensionFunction::ResponseAction
 LanguageSettingsPrivateGetLanguageListFunction::Run() {
-  return RespondNow(OneArgument(new base::ListValue()));
+  // Collect the language codes from the supported accept-languages.
+  const std::string app_locale = g_browser_process->GetApplicationLocale();
+  std::vector<std::string> language_codes;
+  l10n_util::GetAcceptLanguagesForLocale(app_locale, &language_codes);
+
+  // Map of display name -> {language code, native display name}.
+  typedef std::pair<std::string, base::string16> LanguagePair;
+  typedef std::map<base::string16, LanguagePair,
+      l10n_util::StringComparator<base::string16>> LanguageMap;
+
+  // Collator used to sort display names in the current locale.
+  UErrorCode error = U_ZERO_ERROR;
+  scoped_ptr<icu::Collator> collator(icu::Collator::createInstance(
+      icu::Locale(app_locale.c_str()), error));
+  if (U_FAILURE(error))
+    collator.reset();
+  LanguageMap language_map(
+      l10n_util::StringComparator<base::string16>(collator.get()));
+
+  // Build the list of display names and the language map.
+  for (const auto& code : language_codes) {
+    base::string16 display_name = l10n_util::GetDisplayNameForLocale(
+        code, app_locale, false);
+    base::string16 native_display_name = l10n_util::GetDisplayNameForLocale(
+        code, code, false);
+    language_map[display_name] = std::make_pair(code, native_display_name);
+  }
+
+  // Get the list of available locales (display languages) and convert to a set.
+  const std::vector<std::string>& locales = l10n_util::GetAvailableLocales();
+  const std::unordered_set<std::string> locale_set(
+      locales.begin(), locales.end());
+
+  // Get the list of spell check languages and convert to a set.
+  std::vector<std::string> spellcheck_languages;
+  chrome::spellcheck_common::SpellCheckLanguages(&spellcheck_languages);
+  const std::unordered_set<std::string> spellcheck_language_set(
+      spellcheck_languages.begin(), spellcheck_languages.end());
+
+  // Get the list of translatable languages and convert to a set.
+  std::vector<std::string> translate_languages;
+  translate::TranslateDownloadManager::GetSupportedLanguages(

[Seigo Nonaka, 2015/08/11 18:48:35]

Is this function called different from UI thread?
If yes, please double check TranslateDownloadManager::GetSupportedLanguages is
thread-safe or not.
Looks like TranslateDownloadManager::all_supported_languages_ can be accessed
from UI thread. (I'm sorry if this is not the case).

FYI: as far as I know l10n_util is thread-safe. Also
spellcheck_common::SpellCheckLanguages is safe to call from non UI thread.

[hajimehoshi, 2015/08/12 05:34:48]

I don't think this function is thread-safe.

[michaelpg, 2015/08/14 00:10:48]

Could you elaborate on why not?

language_options_handler_common.cc currently calls this on the UI thread, just
like here.

GetSupportedLanguages calls TranslateLanguageList::GetSupportedLanguages. The
only thing that jumps out at me is
TranslateLanguageList::SetResourceRequestsAllowed, called by
TranslateService::OnResourceRequestsAllowed using a
ResourceRequestAllowedNotifier which I have no idea what thread it might run
on...

[michaelpg, 2015/08/14 00:10:49]

This function is called on the UI thread (it's part of a
UIThreadExtensionFunction).

[Seigo Nonaka, 2015/08/14 00:18:47]

Okay, I'm sorry I was not aware of UIThreadExtensionFunction.
If this runs on UI thread, no problem.
Thank you for checking.

+      &translate_languages);
+  const std::unordered_set<std::string> translate_language_set(
+      translate_languages.begin(), translate_languages.end());
+
+  // Build the language list from the language map.
+  scoped_ptr<base::ListValue> language_list(new base::ListValue);
+  for (const auto& entry : language_map) {
+    const base::string16& display_name = entry.first;
+    const LanguagePair& pair = entry.second;
+
+    language_settings_private::Language language;
+    language.code = pair.first;
+
+    base::string16 adjusted_display_name(display_name);
+    base::i18n::AdjustStringForLocaleDirection(&adjusted_display_name);
+    language.display_name = base::UTF16ToUTF8(adjusted_display_name);
+
+    base::string16 adjusted_native_display_name(pair.second);
+    base::i18n::AdjustStringForLocaleDirection(&adjusted_native_display_name);
+    language.native_display_name =
+        base::UTF16ToUTF8(adjusted_native_display_name);
+
+    // Set optional fields only if they differ from the default.
+    if (base::i18n::StringContainsStrongRTLChars(display_name))
+      language.display_name_rtl.reset(new bool(true));
+    if (locale_set.count(pair.first) > 0)
+      language.supports_ui.reset(new bool(true));
+    if (spellcheck_language_set.count(pair.first) > 0)
+      language.supports_spellcheck.reset(new bool(true));
+    if (translate_language_set.count(pair.first) > 0)
+      language.supports_translate.reset(new bool(true));
+
+    language_list->Append(language.ToValue());
+  }
+  return RespondNow(OneArgument(language_list.release()));
 }
 
 LanguageSettingsPrivateSetLanguageListFunction::
-    LanguageSettingsPrivateSetLanguageListFunction() {
+    LanguageSettingsPrivateSetLanguageListFunction()
+    : chrome_details_(this) {
 }
 
 LanguageSettingsPrivateSetLanguageListFunction::
@@ -38,6 +138,11 @@ LanguageSettingsPrivateSetLanguageListFunction::Run() {
       language_settings_private::SetLanguageList::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(parameters.get());
 
+  scoped_ptr<translate::TranslatePrefs> translate_prefs =
+      ChromeTranslateClient::CreateTranslatePrefs(
+          chrome_details_.GetProfile()->GetPrefs());
+  translate_prefs->UpdateLanguageList(parameters->language_codes);
+
   return RespondNow(NoArguments());
 }
 
@@ -51,7 +156,14 @@ LanguageSettingsPrivateGetSpellcheckDictionaryStatusesFunction::
 
 ExtensionFunction::ResponseAction
 LanguageSettingsPrivateGetSpellcheckDictionaryStatusesFunction::Run() {
-  return RespondNow(OneArgument(new base::ListValue()));
+  LanguageSettingsPrivateDelegate* delegate =
+      LanguageSettingsPrivateDelegateFactory::GetForBrowserContext(
+          browser_context());
+
+  scoped_ptr<base::ListValue> return_list(new base::ListValue());
+  for (const auto& status : delegate->GetHunspellDictionaryStatuses())
+    return_list->Append(status->ToValue());
+  return RespondNow(OneArgument(return_list.release()));
 }
 
 LanguageSettingsPrivateGetSpellcheckWordsFunction::
@@ -64,11 +176,23 @@ LanguageSettingsPrivateGetSpellcheckWordsFunction::
 
 ExtensionFunction::ResponseAction
 LanguageSettingsPrivateGetSpellcheckWordsFunction::Run() {
-  return RespondNow(OneArgument(new base::ListValue()));
+  SpellcheckService* service =
+      SpellcheckServiceFactory::GetForContext(browser_context());
+  SpellcheckCustomDictionary* dictionary = service->GetCustomDictionary();
+
+  scoped_ptr<base::ListValue> word_list(new base::ListValue());
+  // TODO(michaelpg): observe the dictionary and respond later if not loaded.
+  if (dictionary->IsLoaded()) {
+    const std::set<std::string>& words = dictionary->GetWords();
+    for (const std::string& word : words)
+      word_list->AppendString(word);
+  }
+  return RespondNow(OneArgument(word_list.release()));
 }
 
 LanguageSettingsPrivateGetTranslateTargetLanguageFunction::
-    LanguageSettingsPrivateGetTranslateTargetLanguageFunction() {
+    LanguageSettingsPrivateGetTranslateTargetLanguageFunction()
+    : chrome_details_(this) {
 }
 
 LanguageSettingsPrivateGetTranslateTargetLanguageFunction::
@@ -77,7 +201,9 @@ LanguageSettingsPrivateGetTranslateTargetLanguageFunction::
 
 ExtensionFunction::ResponseAction
 LanguageSettingsPrivateGetTranslateTargetLanguageFunction::Run() {
-  return RespondNow(OneArgument(new base::StringValue("")));
+  return RespondNow(OneArgument(new base::StringValue(
+      TranslateService::GetTargetLanguage(
+          chrome_details_.GetProfile()->GetPrefs()))));
 }
 
 LanguageSettingsPrivateGetInputMethodListsFunction::