Refactoring for InputMethodAuraLinux.

ui/base/ime/input_method_auralinux.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/base/ime/input_method_auralinux.h"
 
+#include "base/auto_reset.h"
 #include "base/environment.h"
 #include "ui/base/ime/linux/linux_input_method_context_factory.h"
 #include "ui/base/ime/text_input_client.h"
 #include "ui/events/event.h"
 
 namespace ui {
 
 InputMethodAuraLinux::InputMethodAuraLinux(
     internal::InputMethodDelegate* delegate)
-    : allowed_to_fire_vkey_process_key_(false), vkey_processkey_flags_(0) {
+    : text_input_type_(TEXT_INPUT_TYPE_NONE),
+      is_sync_mode_(false),
+      composition_changed_(false),
+      suppress_next_result_(false) {
   SetDelegate(delegate);
+  context_ =
+      LinuxInputMethodContextFactory::instance()->CreateInputMethodContext(
+          this, false);
+  context_simple_ =
+      LinuxInputMethodContextFactory::instance()->CreateInputMethodContext(
+          this, true);
 }
 
 InputMethodAuraLinux::~InputMethodAuraLinux() {}
 
+LinuxInputMethodContext* InputMethodAuraLinux::GetContextForTesting(
+    bool is_simple) {
+  return is_simple ? context_simple_.get() : context_.get();
+}
+
 // Overriden from InputMethod.
 
 void InputMethodAuraLinux::Init(bool focused) {
-  CHECK(LinuxInputMethodContextFactory::instance())
-      << "This failure was likely caused because "
-      << "ui::InitializeInputMethod(ForTesting) was not called "
-      << "before instantiating this class.";
-  input_method_context_ =
-      LinuxInputMethodContextFactory::instance()->CreateInputMethodContext(
-          this);
-  CHECK(input_method_context_.get());
-
   InputMethodBase::Init(focused);
 
-  if (focused) {
-    input_method_context_->OnTextInputTypeChanged(
-        GetTextInputClient() ?
-        GetTextInputClient()->GetTextInputType() :
-        TEXT_INPUT_TYPE_TEXT);
-  }
+  UpdateContextFocusState();
 }
 
 bool InputMethodAuraLinux::OnUntranslatedIMEMessage(
     const base::NativeEvent& event,
     NativeEventResult* result) {
   return false;
 }
 
 bool InputMethodAuraLinux::DispatchKeyEvent(const ui::KeyEvent& event) {
   DCHECK(event.type() == ET_KEY_PRESSED || event.type() == ET_KEY_RELEASED);
   DCHECK(system_toplevel_window_focused());
 
   // If no text input client, do nothing.
   if (!GetTextInputClient())
     return DispatchKeyEventPostIME(event);
 
-  // Let an IME handle the key event first, and allow to fire a VKEY_PROCESSKEY
-  // event for keydown events.  Note that DOM Level 3 Events Sepc requires that
-  // only keydown events fire keyCode=229 events and not for keyup events.
-  if (event.type() == ET_KEY_PRESSED &&
-      (event.flags() & ui::EF_IME_FABRICATED_KEY) == 0)
-    AllowToFireProcessKey(event);
-  if (input_method_context_->DispatchKeyEvent(event))
-    return true;
-  StopFiringProcessKey();
+  suppress_next_result_ = false;
+  composition_changed_ = false;
+  result_text_.clear();
 
-  // Otherwise, insert the character.
-  const bool handled = DispatchKeyEventPostIME(event);
-  if (event.type() == ET_KEY_PRESSED && GetTextInputClient()) {
-    const uint16 ch = event.GetCharacter();
-    if (ch) {
-      GetTextInputClient()->InsertChar(ch, event.flags());
-      return true;
+  bool filtered = false;
+  {
+    base::AutoReset<bool> flipper(&is_sync_mode_, true);
+    if (text_input_type_ != TEXT_INPUT_TYPE_NONE &&
+        text_input_type_ != TEXT_INPUT_TYPE_PASSWORD) {
+      filtered = context_->DispatchKeyEvent(event);
+    } else {
+      filtered = context_simple_->DispatchKeyEvent(event);
     }
   }
-  return handled;
+
+  if (event.type() == ui::ET_KEY_PRESSED && filtered) {
+    if (NeedInsertChar())
+      DispatchKeyEventPostIME(event);
+    else if (HasInputMethodResult())
+      SendFakeProcessKeyEvent(event.flags());
+
+    // Don't send VKEY_PROCESSKEY event if there is no result text or
+    // composition. This is to workaround the weird behavior of IBus with US
+    // keyboard, which mutes the keydown and later fake a new keydown with IME
+    // result in sync mode. In that case, user would expect only
+    // keydown/keypress/keyup event without an initial 229 keydown event.
+  }
+
+  TextInputClient* client = GetTextInputClient();
+  // Processes the result text before composition for sync mode.
+  if (!result_text_.empty()) {
+    if (filtered && NeedInsertChar()) {
+      for (const auto ch : result_text_)
+        client->InsertChar(ch, event.flags());
+    } else {
+      // If |filtered| is false, that means the IME wants to commit some text
+      // but still release the key to the application. For example, Korean IME
+      // handles ENTER key to confirm its composition but still release it for
+      // the default behavior (e.g. trigger search, etc.)
+      // In such case, don't do InsertChar because a key should only trigger the
+      // keydown event once.
+      client->InsertText(result_text_);
+    }
+  }
+
+  if (composition_changed_ && !IsTextInputTypeNone()) {
+    // If composition changed, does SetComposition if composition is not empty.
+    // And ClearComposition if composition is empty.
+    if (!composition_.text.empty())
+      client->SetCompositionText(composition_);
+    else if (result_text_.empty())
+      client->ClearCompositionText();
+  }
+
+  // Makes sure the cached composition is cleared after committing any text or
+  // cleared composition.
+  if (!client->HasCompositionText())
+    composition_.Clear();
+
+  if (!filtered) {
+    DispatchKeyEventPostIME(event);
+    if (event.type() == ui::ET_KEY_PRESSED) {
+      // If a key event was not filtered by |context_| or |context_simple_|,
+      // then it means the key event didn't generate any result text. For some
+      // cases, the key event may still generate a valid character, eg. a
+      // control-key event (ctrl-a, return, tab, etc.). We need to send the
+      // character to the focused text input client by calling
+      // TextInputClient::InsertChar().
+      // Note: don't use |client| and use GetTextInputClient() here because
+      // DispatchKeyEventPostIME may cause the current text input client change.
+      base::char16 ch = event.GetCharacter();
+      if (ch && GetTextInputClient())
+        GetTextInputClient()->InsertChar(ch, event.flags());
+    }
+  }
+
+  return true;
+}
+
+void InputMethodAuraLinux::UpdateContextFocusState() {
+  bool old_text_input_type = text_input_type_;
+  text_input_type_ = GetTextInputType();
+
+  // We only focus in |context_| when the focus is in a textfield.
+  if (old_text_input_type != TEXT_INPUT_TYPE_NONE &&
+      text_input_type_ == TEXT_INPUT_TYPE_NONE) {
+    context_->Blur();
+  } else if (old_text_input_type == TEXT_INPUT_TYPE_NONE &&
+             text_input_type_ != TEXT_INPUT_TYPE_NONE) {
+    context_->Focus();
+  }
+
+  // |context_simple_| can be used in any textfield, including password box, and
+  // even if the focused text input client's text input type is
+  // ui::TEXT_INPUT_TYPE_NONE.
+  if (GetTextInputClient())
+    context_simple_->Focus();
+  else
+    context_simple_->Blur();
 }
 
 void InputMethodAuraLinux::OnTextInputTypeChanged(
     const TextInputClient* client) {
-  if (!IsTextInputClientFocused(client))
-    return;
-  input_method_context_->Reset();
+  UpdateContextFocusState();
   // TODO(yoichio): Support inputmode HTML attribute.
-  input_method_context_->OnTextInputTypeChanged(client->GetTextInputType());
 }
 
 void InputMethodAuraLinux::OnCaretBoundsChanged(const TextInputClient* client) {
   if (!IsTextInputClientFocused(client))
     return;
-  input_method_context_->OnCaretBoundsChanged(
-      GetTextInputClient()->GetCaretBounds());
+  context_->SetCursorLocation(GetTextInputClient()->GetCaretBounds());
 }
 
 void InputMethodAuraLinux::CancelComposition(const TextInputClient* client) {
   if (!IsTextInputClientFocused(client))
     return;
-  input_method_context_->Reset();
-  input_method_context_->OnTextInputTypeChanged(client->GetTextInputType());
+  ResetContext();
+}
+
+void InputMethodAuraLinux::ResetContext() {
+  if (!GetTextInputClient())
+    return;
+
+  // To prevent any text from being committed when resetting the |context_|;
+  is_sync_mode_ = true;
+  suppress_next_result_ = true;
+
+  context_->Reset();
+  context_simple_->Reset();
+
+  // Some input methods may not honour the reset call. Focusing out/in the
+  // |context_| to make sure it gets reset correctly.
+  if (text_input_type_ != TEXT_INPUT_TYPE_NONE) {
+    context_->Blur();
+    context_->Focus();
+  }
+
+  composition_.Clear();
+  result_text_.clear();
+  is_sync_mode_ = false;
+  composition_changed_ = false;
 }
 
 void InputMethodAuraLinux::OnInputLocaleChanged() {
 }
 
 std::string InputMethodAuraLinux::GetInputLocale() {
   return "";
 }
 
 bool InputMethodAuraLinux::IsActive() {
   // InputMethodAuraLinux is always ready and up.
   return true;
 }
 
 bool InputMethodAuraLinux::IsCandidatePopupOpen() const {
   // There seems no way to detect candidate windows or any popups.
   return false;
 }
 
 // Overriden from ui::LinuxInputMethodContextDelegate
 
 void InputMethodAuraLinux::OnCommit(const base::string16& text) {
-  MaybeFireProcessKey();
-  if (!IsTextInputTypeNone())
+  if (suppress_next_result_ || !GetTextInputClient()) {
+    suppress_next_result_ = false;
+    return;
+  }
+
+  if (is_sync_mode_) {
+    // Append the text to the buffer, because commit signal might be fired
+    // multiple times when processing a key event.
+    result_text_.append(text);
+  } else if (!IsTextInputTypeNone()) {
+    // If we are not handling key event, do not bother sending text result if
+    // the focused text input client does not support text input.
+    SendFakeProcessKeyEvent(0);
     GetTextInputClient()->InsertText(text);
+    composition_.Clear();
+  }
 }
 
 void InputMethodAuraLinux::OnPreeditChanged(
     const CompositionText& composition_text) {
-  MaybeFireProcessKey();
-  TextInputClient* text_input_client = GetTextInputClient();
-  if (text_input_client)
-    text_input_client->SetCompositionText(composition_text);
+  if (suppress_next_result_ || IsTextInputTypeNone())
+    return;
+
+  composition_ = composition_text;
+
+  if (is_sync_mode_) {
+    if (!composition_.text.empty() || !composition_text.text.empty())
+      composition_changed_ = true;
+  } else {
+    SendFakeProcessKeyEvent(0);
+    GetTextInputClient()->SetCompositionText(composition_text);
+  }
 }
 
 void InputMethodAuraLinux::OnPreeditEnd() {
-  MaybeFireProcessKey();
-  TextInputClient* text_input_client = GetTextInputClient();
-  if (text_input_client && text_input_client->HasCompositionText())
-    text_input_client->ClearCompositionText();
-}
+  if (suppress_next_result_ || IsTextInputTypeNone())
+    return;
 
-void InputMethodAuraLinux::OnPreeditStart() {
-  MaybeFireProcessKey();
+  if (is_sync_mode_) {
+    if (!composition_.text.empty()) {
+      composition_.Clear();
+      composition_changed_ = true;
+    }
+  } else {
+    TextInputClient* client = GetTextInputClient();
+    if (client && client->HasCompositionText()) {
+      SendFakeProcessKeyEvent(0);
+      client->ClearCompositionText();
+    }
+    composition_.Clear();
+  }
 }
 
 // Overridden from InputMethodBase.
 
+void InputMethodAuraLinux::OnFocus() {
+  InputMethodBase::OnFocus();
+  UpdateContextFocusState();
+}
+
+void InputMethodAuraLinux::OnBlur() {
+  ConfirmCompositionText();
+  InputMethodBase::OnBlur();
+  UpdateContextFocusState();
+}
+
+void InputMethodAuraLinux::OnWillChangeFocusedClient(
+    TextInputClient* focused_before,
+    TextInputClient* focused) {
+  ConfirmCompositionText();
+}
+
 void InputMethodAuraLinux::OnDidChangeFocusedClient(
     TextInputClient* focused_before,
     TextInputClient* focused) {
-  input_method_context_->Reset();
-  input_method_context_->OnTextInputTypeChanged(
-      focused ? focused->GetTextInputType() : TEXT_INPUT_TYPE_NONE);
+  UpdateContextFocusState();
+
+  // Force to update caret bounds, in case the View thinks that the caret
+  // bounds has not changed.
+  if (text_input_type_ != TEXT_INPUT_TYPE_NONE)
+    OnCaretBoundsChanged(GetTextInputClient());
 
   InputMethodBase::OnDidChangeFocusedClient(focused_before, focused);
 }
 
-// Helper functions to support VKEY_PROCESSKEY.
+// private
 
-void InputMethodAuraLinux::AllowToFireProcessKey(const ui::KeyEvent& event) {
-  allowed_to_fire_vkey_process_key_ = true;
-  vkey_processkey_flags_ = event.flags();
+bool InputMethodAuraLinux::HasInputMethodResult() {
+  return !result_text_.empty() || composition_changed_;
 }
 
-void InputMethodAuraLinux::MaybeFireProcessKey() {
-  if (!allowed_to_fire_vkey_process_key_)
-    return;
-
-  const ui::KeyEvent fabricated_event(ET_KEY_PRESSED,
-                                      VKEY_PROCESSKEY,
-                                      vkey_processkey_flags_);
-  DispatchKeyEventPostIME(fabricated_event);
-  StopFiringProcessKey();
+bool InputMethodAuraLinux::NeedInsertChar() const {
+  return IsTextInputTypeNone() ||
+         (!composition_changed_ && composition_.text.empty() &&
+          result_text_.length() == 1);
 }
 
-void InputMethodAuraLinux::StopFiringProcessKey() {
-  allowed_to_fire_vkey_process_key_ = false;
-  vkey_processkey_flags_ = 0;
+void InputMethodAuraLinux::SendFakeProcessKeyEvent(int flags) const {
+  DispatchKeyEventPostIME(
+      KeyEvent(ui::ET_KEY_PRESSED, ui::VKEY_PROCESSKEY, flags));
+}
+
+void InputMethodAuraLinux::ConfirmCompositionText() {
+  TextInputClient* client = GetTextInputClient();
+  if (client && client->HasCompositionText())
+    client->ConfirmCompositionText();
+
+  ResetContext();
 }
 
 }  // namespace ui