Introduce WebInputMethodController to blink

third_party/WebKit/Source/web/WebInputMethodControllerImpl.cpp

+// Copyright 2016 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 "web/WebInputMethodControllerImpl.h"
+
+#include "core/InputTypeNames.h"
+#include "core/dom/DocumentUserGestureToken.h"
+#include "core/editing/EditingUtilities.h"
+#include "core/editing/Editor.h"
+#include "core/editing/EphemeralRange.h"
+#include "core/editing/FrameSelection.h"
+#include "core/editing/InputMethodController.h"
+#include "core/editing/PlainTextRange.h"
+#include "core/frame/LocalFrame.h"
+#include "core/page/FocusController.h"
+#include "core/page/Page.h"
+#include "platform/UserGestureIndicator.h"
+#include "public/platform/WebString.h"
+#include "public/web/WebPlugin.h"
+#include "public/web/WebRange.h"
+#include "web/CompositionUnderlineVectorBuilder.h"
+#include "web/WebLocalFrameImpl.h"
+#include "web/WebPluginContainerImpl.h"
+
+namespace blink {
+
+WebInputMethodControllerImpl::WebInputMethodControllerImpl(
+    WebLocalFrameImpl* webLocalFrame)
+    : m_webLocalFrame(webLocalFrame), m_suppressNextKeypressEvent(false) {}
+
+WebInputMethodControllerImpl::~WebInputMethodControllerImpl() {}
+
+// static
+WebInputMethodControllerImpl* WebInputMethodControllerImpl::fromFrame(
+    LocalFrame* frame) {
+  WebLocalFrameImpl* webLocalFrameImpl = WebLocalFrameImpl::fromFrame(frame);
+  return webLocalFrameImpl ? webLocalFrameImpl->inputMethodController()
+                           : nullptr;
+}
+
+DEFINE_TRACE(WebInputMethodControllerImpl) {
+  visitor->trace(m_webLocalFrame);
+}
+
+bool WebInputMethodControllerImpl::setComposition(
+    const WebString& text,
+    const WebVector<WebCompositionUnderline>& underlines,
+    int selectionStart,
+    int selectionEnd) {
+  if (WebPlugin* plugin = focusedPluginIfInputMethodSupported()) {
+    return plugin->setComposition(text, underlines, selectionStart,
+                                  selectionEnd);
+  }
+
+  // We should use this |editor| object only to complete the ongoing
+  // composition.
+  if (!frame()->editor().canEdit() && !inputMethodController().hasComposition())
+    return false;
+
+  // We should verify the parent node of this IME composition node are
+  // editable because JavaScript may delete a parent node of the composition
+  // node. In this case, WebKit crashes while deleting texts from the parent
+  // node, which doesn't exist any longer.
+  const EphemeralRange range =
+      inputMethodController().compositionEphemeralRange();
+  if (range.isNotNull()) {
+    Node* node = range.startPosition().computeContainerNode();
+    frame()->document()->updateStyleAndLayoutTree();
+    if (!node || !hasEditableStyle(*node))
+      return false;
+  }
+
+  // A keypress event is canceled. If an ongoing composition exists, then the
+  // keydown event should have arisen from a handled key (e.g., backspace).
+  // In this case we ignore the cancellation and continue; otherwise (no
+  // ongoing composition) we exit and signal success only for attempts to
+  // clear the composition.
+  if (m_suppressNextKeypressEvent && !inputMethodController().hasComposition())
+    return text.isEmpty();
+
+  UserGestureIndicator gestureIndicator(DocumentUserGestureToken::create(
+      frame()->document(), UserGestureToken::NewGesture));
+
+  // When the range of composition underlines overlap with the range between
+  // selectionStart and selectionEnd, WebKit somehow won't paint the selection
+  // at all (see InlineTextBox::paint() function in InlineTextBox.cpp).
+  // But the selection range actually takes effect.
+  inputMethodController().setComposition(
+      String(text), CompositionUnderlineVectorBuilder(underlines),
+      selectionStart, selectionEnd);
+
+  return text.isEmpty() || inputMethodController().hasComposition();
+}
+
+bool WebInputMethodControllerImpl::finishComposingText(
+    ConfirmCompositionBehavior selectionBehavior) {
+  // TODO(ekaramad): Here and in other IME calls we should expect the
+  // call to be made when our frame is focused. This, however, is not the case
+  // all the time. For instance, resetInputMethod call on RenderViewImpl could
+  // be after losing the focus on frame. But since we return the core frame
+  // in WebViewImpl::focusedLocalFrameInWidget(), we will reach here with
+  // |m_webLocalFrame| not focused on page.
+
+  if (WebPlugin* plugin = focusedPluginIfInputMethodSupported())
+    return plugin->finishComposingText(selectionBehavior);
+  return inputMethodController().finishComposingText(
+      selectionBehavior == WebInputMethodController::KeepSelection
+          ? InputMethodController::KeepSelection
+          : InputMethodController::DoNotKeepSelection);
+}
+
+bool WebInputMethodControllerImpl::commitText(const WebString& text,
+                                              int relativeCaretPosition) {
+  UserGestureIndicator gestureIndicator(DocumentUserGestureToken::create(
+      frame()->document(), UserGestureToken::NewGesture));
+
+  if (WebPlugin* plugin = focusedPluginIfInputMethodSupported())
+    return plugin->commitText(text, relativeCaretPosition);
+
+  // TODO(xiaochengh): The use of updateStyleAndLayoutIgnorePendingStylesheets
+  // needs to be audited.  See http://crbug.com/590369 for more details.
+  frame()->document()->updateStyleAndLayoutIgnorePendingStylesheets();
+
+  return inputMethodController().commitText(text, relativeCaretPosition);
+}
+
+LocalFrame* WebInputMethodControllerImpl::frame() const {
+  return m_webLocalFrame->frame();
+}
+
+InputMethodController& WebInputMethodControllerImpl::inputMethodController()
+    const {
+  return frame()->inputMethodController();
+}
+
+WebPlugin* WebInputMethodControllerImpl::focusedPluginIfInputMethodSupported()
+    const {
+  WebPluginContainerImpl* container =
+      WebLocalFrameImpl::currentPluginContainer(frame());
+  if (container && container->supportsInputMethod())
+    return container->plugin();
+  return nullptr;
+}
+
+}  // namespace blink