Sync starting language and input method preferences

chrome/browser/chromeos/preferences.cc

Index: chrome/browser/chromeos/preferences.cc
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index fd7b1940c28d75f0d88f82b096e378850df4ab22..1de6d9e19193091f393b15590a058d75ee3bf23c 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -4,7 +4,7 @@
 
 #include "chrome/browser/chromeos/preferences.h"
 
-#include <vector>
+#include <algorithm>
 
 #include "ash/autoclick/autoclick_controller.h"
 #include "ash/magnifier/magnifier_constants.h"
@@ -31,6 +31,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
+#include "chromeos/ime/component_extension_ime_manager.h"
 #include "chromeos/ime/extension_ime_util.h"
 #include "chromeos/ime/ime_keyboard.h"
 #include "chromeos/ime/input_method_manager.h"
@@ -38,20 +39,132 @@
 #include "components/feedback/tracing_manager.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/user_manager/user.h"
+#include "content/public/browser/browser_thread.h"
 #include "third_party/icu/source/i18n/unicode/timezone.h"
+#include "ui/base/l10n/l10n_util.h"
 #include "ui/events/event_constants.h"
 #include "ui/events/event_utils.h"
 #include "url/gurl.h"
 
 namespace chromeos {
+namespace {
 
 static const char kFallbackInputMethodLocale[] = "en-US";
 
+// Checks input method IDs, converting engine IDs to input method IDs and
+// removing unsupported IDs from |values|.
+void CheckAndResolveInputMethodIDs(
+    std::vector<std::string>* values,
+    const input_method::InputMethodDescriptors& supported_descriptors) {
+  // Extract the supported input method IDs into a set.
+  std::set<std::string> supported_input_method_ids;
+  for (size_t i = 0; i < supported_descriptors.size(); i++)
+    supported_input_method_ids.insert(supported_descriptors[i].id());
+
+  // Convert engine IDs to input method extension IDs.
+  std::transform(values->begin(), values->end(), values->begin(),
+                 extension_ime_util::GetInputMethodIDByEngineID);
+
+  // Remove values that aren't found in the set of supported input method IDs.
+  std::vector<std::string>::iterator it = values->begin();
+  while (it != values->end()) {
+    if (it->size() && std::find(supported_input_method_ids.begin(),
+                                supported_input_method_ids.end(),
+                                *it) != supported_input_method_ids.end()) {
+      ++it;
+    } else {
+      it = values->erase(it);
+    }
+  }
+}
+
+// Checks whether each language is supported, replacing locales with variants
+// if they are available. Must be called on a thread that allows IO.
+void CheckAndResolveLocales(std::string* languages) {
+  if (languages->empty())
+    return;
+  std::vector<std::string> values;
+  base::SplitString(*languages, ',', &values);
+
+  // Remove unsupported language values and set the resolved locales.
+  std::vector<std::string>::iterator value_iter = values.begin();
+  while (value_iter != values.end()) {
+    std::string resolved_locale;
+    if (l10n_util::CheckAndResolveLocale(*value_iter, &resolved_locale)) {
+      *value_iter = resolved_locale;
+      ++value_iter;
+    } else {
+      value_iter = values.erase(value_iter);
+    }
+  }
+
+  *languages = JoinString(values, ',');
+}
+
+// Appends tokens from |src| that are not in |dest| to |dest|. Quadratic
+// runtime; use only for small lists.
+void MergeLists(std::vector<std::string>* dest,
+                const std::vector<std::string>& src) {
+  for (size_t i = 0; i < src.size(); i++) {
+    // Skip token if it's already in |dest|.
+    if (std::find(dest->begin(), dest->end(), src[i]) == dest->end())
+      dest->push_back(src[i]);
+  }
+}
+
+// For the given input method pref, adds unique values from |synced_pref| to
+// values in |pref|. The new values are converted from legacy engine IDs to
+// input method IDs if necessary.
+std::string AddSupportedInputMethodValues(const std::string& pref,
+                                          const std::string& synced_pref,
+                                          const char* pref_name) {
+  std::vector<std::string> old_tokens;
+  std::vector<std::string> new_tokens;
+  base::SplitString(pref, ',', &old_tokens);
+  base::SplitString(synced_pref, ',', &new_tokens);
+
+  // Check and convert the new tokens.
+  if (pref_name == prefs::kLanguagePreloadEngines ||
+      pref_name == prefs::kLanguageEnabledExtensionImes) {
+    input_method::InputMethodManager* manager =
+        input_method::InputMethodManager::Get();
+    scoped_ptr<input_method::InputMethodDescriptors> supported_descriptors;
+
+    if (pref_name == prefs::kLanguagePreloadEngines) {
+      // Set the known input methods.
+      supported_descriptors = manager->GetSupportedInputMethods();
+      // Add the available component extension IMEs.
+      ComponentExtensionIMEManager* component_extension_manager =
+          manager->GetComponentExtensionIMEManager();
+      if (component_extension_manager->IsInitialized()) {
+        input_method::InputMethodDescriptors component_descriptors =
+            component_extension_manager->GetAllIMEAsInputMethodDescriptor();
+        supported_descriptors->insert(supported_descriptors->end(),
+                                      component_descriptors.begin(),
+                                      component_descriptors.end());
+      }
+    } else {
+      supported_descriptors.reset(new input_method::InputMethodDescriptors);
+      manager->GetInputMethodExtensions(supported_descriptors.get());
+    }
+    CheckAndResolveInputMethodIDs(&new_tokens, *supported_descriptors);
+  } else if (pref_name != prefs::kLanguagePreferredLanguages) {
+    NOTREACHED() << "Attempting to merge an invalid preference.";
+  }
+
+  // Do the actual merging.
+  MergeLists(&old_tokens, new_tokens);
+  return JoinString(old_tokens, ',');
+}
+
+}  // anonymous namespace
+
 Preferences::Preferences()
     : prefs_(NULL),
       input_method_manager_(input_method::InputMethodManager::Get()),
       user_(NULL),
-      user_is_primary_(false) {
+      user_is_primary_(false),
+      weak_factory_(this) {
   // Do not observe shell, if there is no shell instance; e.g., in some unit
   // tests.
   if (ash::Shell::HasInstance())
@@ -62,7 +175,8 @@ Preferences::Preferences(input_method::InputMethodManager* input_method_manager)
     : prefs_(NULL),
       input_method_manager_(input_method_manager),
       user_(NULL),
-      user_is_primary_(false) {
+      user_is_primary_(false),
+      weak_factory_(this) {
   // Do not observe shell, if there is no shell instance; e.g., in some unit
   // tests.
   if (ash::Shell::HasInstance())
@@ -214,21 +328,34 @@ void Preferences::RegisterProfilePrefs(
       prefs::kLanguagePreviousInputMethod,
       "",
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
-  // We don't sync the list of input methods and preferred languages since a
-  // user might use two or more devices with different hardware keyboards.
-  // crosbug.com/15181
   registry->RegisterStringPref(
       prefs::kLanguagePreferredLanguages,
       kFallbackInputMethodLocale,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterStringPref(
+      prefs::kLanguagePreferredLanguagesSyncable,
+      "",
+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterStringPref(
       prefs::kLanguagePreloadEngines,
       hardware_keyboard_id,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterStringPref(
+      prefs::kLanguagePreloadEnginesSyncable,
+      "",
+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterStringPref(
       prefs::kLanguageEnabledExtensionImes,
       "",
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+  registry->RegisterStringPref(
+      prefs::kLanguageEnabledExtensionImesSyncable,
+      "",
+      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterBooleanPref(
+      prefs::kLanguageShouldMergeInputMethods,
+      false,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 
   registry->RegisterIntegerPref(
       prefs::kLanguageRemapSearchKeyTo,
@@ -333,9 +460,17 @@ void Preferences::InitUserPrefs(PrefServiceSyncable* prefs) {
                                    prefs, callback);
   touch_hud_projection_enabled_.Init(prefs::kTouchHudProjectionEnabled,
                                      prefs, callback);
+  preferred_languages_.Init(prefs::kLanguagePreferredLanguages,
+                            prefs, callback);
   preload_engines_.Init(prefs::kLanguagePreloadEngines, prefs, callback);
   enabled_extension_imes_.Init(prefs::kLanguageEnabledExtensionImes,
                                prefs, callback);
+  preferred_languages_syncable_.Init(prefs::kLanguagePreferredLanguagesSyncable,
+                                     prefs, callback);
+  preload_engines_syncable_.Init(prefs::kLanguagePreloadEnginesSyncable,
+                                 prefs, callback);
+  enabled_extension_imes_syncable_.Init(
+      prefs::kLanguageEnabledExtensionImesSyncable, prefs, callback);
   current_input_method_.Init(prefs::kLanguageCurrentInputMethod,
                              prefs, callback);
   previous_input_method_.Init(prefs::kLanguagePreviousInputMethod,
@@ -516,7 +651,9 @@ void Preferences::ApplyPreferences(ApplyReason reason,
       pref_name == prefs::kTouchHudProjectionEnabled) {
     if (user_is_active) {
       const bool enabled = touch_hud_projection_enabled_.GetValue();
-      ash::Shell::GetInstance()->SetTouchHudProjectionEnabled(enabled);
+      // There may not be a shell, e.g., in some unit tests.
+      if (ash::Shell::HasInstance())
+        ash::Shell::GetInstance()->SetTouchHudProjectionEnabled(enabled);
     }
   }
 
@@ -536,25 +673,28 @@ void Preferences::ApplyPreferences(ApplyReason reason,
       UpdateAutoRepeatRate();
   }
 
+  if (reason == REASON_PREF_CHANGED &&
+      pref_name == prefs::kLanguagePreferredLanguages)
+    SetSyncableInputMethodPrefs();
+
   if (reason != REASON_PREF_CHANGED && user_is_active) {
     SetInputMethodList();
-  } else if (pref_name == prefs::kLanguagePreloadEngines && user_is_active) {
-    SetLanguageConfigStringListAsCSV(language_prefs::kGeneralSectionName,
-                                     language_prefs::kPreloadEnginesConfigName,
-                                     preload_engines_.GetValue());
+  } else if (pref_name == prefs::kLanguagePreloadEngines) {
+    if (user_is_active) {
+      SetLanguageConfigStringListAsCSV(
+          language_prefs::kGeneralSectionName,
+          language_prefs::kPreloadEnginesConfigName,
+          preload_engines_.GetValue());
+    }
+    SetSyncableInputMethodPrefs();
   }
 
   if (reason != REASON_PREF_CHANGED ||
       pref_name == prefs::kLanguageEnabledExtensionImes) {
-    if (user_is_active) {
-      std::string value(enabled_extension_imes_.GetValue());
-
-      std::vector<std::string> split_values;
-      if (!value.empty())
-        base::SplitString(value, ',', &split_values);
-
-      input_method_manager_->SetEnabledExtensionImes(&split_values);
-    }
+    if (user_is_active)
+      SetEnabledExtensionImes();
+    if (reason == REASON_PREF_CHANGED)
+      SetSyncableInputMethodPrefs();
   }
 
   if (user_is_active) {
@@ -567,6 +707,10 @@ void Preferences::ApplyPreferences(ApplyReason reason,
 void Preferences::OnIsSyncingChanged() {
   DVLOG(1) << "OnIsSyncingChanged";
   ForceNaturalScrollDefault();
+  if (prefs_->GetBoolean(prefs::kLanguageShouldMergeInputMethods) &&
+      prefs_->IsSyncing()) {
+    MergeSyncedInputMethods();
+  }
 }
 
 void Preferences::ForceNaturalScrollDefault() {
@@ -601,6 +745,15 @@ void Preferences::SetLanguageConfigStringListAsCSV(const char* section,
   }
 }
 
+void Preferences::SetPreferredLanguages(scoped_ptr<std::string> languages) {
+  // Since this only removes locales that are unsupported on this system, we
+  // don't need to update the syncable prefs. If the local preference changes
+  // later, the sync server will lose the values we dropped, but that's okay
+  // since the values from this device would become the new defaults anyway.
+  if (*languages != preferred_languages_.GetValue())
+    preferred_languages_.SetValue(*languages);
+}
+
 void Preferences::SetInputMethodList() {
   // When |preload_engines_| are set, InputMethodManager::ChangeInputMethod()
   // might be called to change the current input method to the first one in the
@@ -626,6 +779,70 @@ void Preferences::SetInputMethodList() {
     input_method_manager_->ChangeInputMethod(current_input_method_id);
 }
 
+void Preferences::SetEnabledExtensionImes() {
+  std::string value(enabled_extension_imes_.GetValue());
+  std::vector<std::string> split_values;
+  if (!value.empty())
+    base::SplitString(value, ',', &split_values);
+  input_method_manager_->SetEnabledExtensionImes(&split_values);
+}
+
+void Preferences::SetSyncableInputMethodPrefs() {
+  // Set the language and input prefs at the same time. Otherwise, we may,
+  // e.g., use a stale languages setting but push a new preload engines setting.
+  preferred_languages_syncable_.SetValue(preferred_languages_.GetValue());
+  enabled_extension_imes_syncable_.SetValue(
+      enabled_extension_imes_.GetValue());
+
+  // For preload engines, use legacy xkb IDs so the preference can sync
+  // across Chrome OS and Chromium OS.
+  std::vector<std::string> engines;
+  base::SplitString(preload_engines_.GetValue(), ',', &engines);
+  std::transform(engines.begin(), engines.end(), engines.begin(),
+                 extension_ime_util::GetEngineIDByInputMethodID);
+  preload_engines_syncable_.SetValue(JoinString(engines, ','));
+}
+
+void Preferences::MergeSyncedInputMethods() {
+  // This should only be done on the first ever sync.
+  DCHECK(prefs_->GetBoolean(prefs::kLanguageShouldMergeInputMethods));
+  prefs_->SetBoolean(prefs::kLanguageShouldMergeInputMethods, false);
+
+  // Get the syncable values, because they will be overwritten once the local
+  // preferences are set.
+  std::string preferred_languages_syncable =
+      preferred_languages_syncable_.GetValue();
+  std::string preload_engines_syncable =
+      preload_engines_syncable_.GetValue();
+  std::string enabled_extension_imes_syncable =
+      enabled_extension_imes_syncable_.GetValue();
+
+  // Merge the values from the sync server into the local values.
+  prefs_->SetString(prefs::kLanguagePreferredLanguages,
+      AddSupportedInputMethodValues(preferred_languages_.GetValue(),
+                                    preferred_languages_syncable,
+                                    prefs::kLanguagePreferredLanguages));
+  prefs_->SetString(prefs::kLanguagePreloadEngines,
+      AddSupportedInputMethodValues(preload_engines_.GetValue(),
+                                    preload_engines_syncable,
+                                    prefs::kLanguagePreloadEngines));
+  prefs_->SetString(prefs::kLanguageEnabledExtensionImes,
+      AddSupportedInputMethodValues(enabled_extension_imes_.GetValue(),
+                                    enabled_extension_imes_syncable,
+                                    prefs::kLanguageEnabledExtensionImes));
+
+  // Check the new list of preferred languages to remove unsupported locales.
+  scoped_ptr<std::string> languages(
+      new std::string(preferred_languages_.GetValue()));
+  content::BrowserThread::PostTaskAndReply(
+      content::BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(&CheckAndResolveLocales, languages.get()),
+      base::Bind(&Preferences::SetPreferredLanguages,
+                 weak_factory_.GetWeakPtr(),
+                 base::Passed(&languages)));
+}
+
 void Preferences::UpdateAutoRepeatRate() {
   input_method::AutoRepeatRate rate;
   rate.initial_delay_in_ms = xkb_auto_repeat_delay_pref_.GetValue();