Fix text selection and input method query

Instruct the render process to change the text selection if it was
requested via an input method event. Raise the selectionChanged() signal
when all the corresponding input method properties are set.

Moreover, add back the remaining input method widget auto tests. The
updated tests are moved to the QWebEngineView tests since the
corresponding APIs (inputMethodQuery() and input event handling) are now
available via the QWebEngineView's focus proxy (aka RWHV).

Task-number: QTBUG-55766
Change-Id: Ia0022d5f38b31dd59b084ff42e4abc2780ae90ec
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

2 files changed, 205 insertions, 54 deletions

diff --git a/src/core/render_widget_host_view_qt.cpp b/src/core/render_widget_host_view_qt.cpp
index f96329139..619577d93 100644
--- a/src/core/render_widget_host_view_qt.cpp
+++ b/src/core/render_widget_host_view_qt.cpp
@@ -54,9 +54,10 @@
 #include "base/command_line.h"
 #include "cc/output/direct_renderer.h"
 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
+#include "content/browser/frame_host/frame_tree.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
-#include "content/browser/renderer_host/text_input_manager.h"
 #include "content/common/cursors/webcursor.h"
+#include "content/common/input_messages.h"
 #include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
@@ -92,6 +93,13 @@
 
 namespace QtWebEngineCore {
 
+enum ImStateFlags {
+    TextInputStateUpdated = 1 << 0,
+    TextSelectionUpdated = 1 << 1,
+    TextSelectionBoundsUpdated = 1 << 2,
+    AllFlags = TextInputStateUpdated | TextSelectionUpdated | TextSelectionBoundsUpdated
+};
+
 static inline ui::LatencyInfo CreateLatencyInfo(const blink::WebInputEvent& event) {
   ui::LatencyInfo latency_info;
   // The latency number should only be added if the timestamp is valid.
@@ -238,13 +246,17 @@ RenderWidgetHostViewQt::RenderWidgetHostViewQt(content::RenderWidgetHost* widget
     , m_needsDelegatedFrameAck(false)
     , m_loadVisuallyCommittedState(NotCommitted)
     , m_adapterClient(0)
-    , m_currentInputType(ui::TEXT_INPUT_TYPE_NONE)
     , m_imeInProgress(false)
     , m_receivedEmptyImeText(false)
     , m_initPending(false)
     , m_beginFrameSource(nullptr)
     , m_needsBeginFrames(false)
     , m_addedFrameObserver(false)
+    , m_imState(0)
+    , m_anchorPositionWithinSelection(0)
+    , m_cursorPositionWithinSelection(0)
+    , m_cursorPosition(0)
+    , m_emptyPreviousSelection(true)
 {
     m_host->SetView(this);
 #ifndef QT_NO_ACCESSIBILITY
@@ -255,6 +267,9 @@ RenderWidgetHostViewQt::RenderWidgetHostViewQt(content::RenderWidgetHost* widget
     auto* task_runner = base::ThreadTaskRunnerHandle::Get().get();
     m_beginFrameSource.reset(new cc::DelayBasedBeginFrameSource(
             base::MakeUnique<cc::DelayBasedTimeSource>(task_runner)));
+
+    if (GetTextInputManager())
+        GetTextInputManager()->AddObserver(this);
 }
 
 RenderWidgetHostViewQt::~RenderWidgetHostViewQt()
@@ -263,6 +278,9 @@ RenderWidgetHostViewQt::~RenderWidgetHostViewQt()
 #ifndef QT_NO_ACCESSIBILITY
     QAccessible::removeActivationObserver(this);
 #endif // QT_NO_ACCESSIBILITY
+
+    if (text_input_manager_)
+        text_input_manager_->RemoveObserver(this);
 }
 
 void RenderWidgetHostViewQt::setDelegate(RenderWidgetHostViewQtDelegate* delegate)
@@ -576,15 +594,6 @@ void RenderWidgetHostViewQt::SetIsLoading(bool)
     // We use WebContentsDelegateQt::LoadingStateChanged to notify about loading state.
 }
 
-void RenderWidgetHostViewQt::TextInputStateChanged(const content::TextInputState &params)
-{
-    m_currentInputType = params.type;
-    m_delegate->inputMethodStateChanged(params.type != ui::TEXT_INPUT_TYPE_NONE);
-    m_delegate->setInputMethodHints(toQtInputMethodHints(params.type));
-
-    m_surroundingText = QString::fromStdString(params.value);
-}
-
 void RenderWidgetHostViewQt::ImeCancelComposition()
 {
     qApp->inputMethod()->reset();
@@ -707,16 +716,114 @@ void RenderWidgetHostViewQt::ClearCompositorFrame()
 {
 }
 
-void RenderWidgetHostViewQt::SelectionChanged(const base::string16 &text, size_t offset, const gfx::Range &range)
+void RenderWidgetHostViewQt::OnUpdateTextInputStateCalled(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view, bool did_update_state)
 {
-    content::RenderWidgetHostViewBase::SelectionChanged(text, offset, range);
-    m_adapterClient->selectionChanged();
+    Q_UNUSED(text_input_manager);
+    Q_UNUSED(updated_view);
+    Q_UNUSED(did_update_state);
+
+    ui::TextInputType type = getTextInputType();
+    m_delegate->inputMethodStateChanged(type != ui::TEXT_INPUT_TYPE_NONE);
+    m_delegate->setInputMethodHints(toQtInputMethodHints(type));
+
+    const content::TextInputState *state = text_input_manager_->GetTextInputState();
+    if (!state)
+        return;
+
+    if (GetSelectedText().empty())
+        m_cursorPosition = state->selection_start;
+
+    m_surroundingText = QString::fromStdString(state->value);
+
+    // Remove IME composition text from the surrounding text
+    if (state->composition_start != -1 && state->composition_end != -1)
+        m_surroundingText.remove(state->composition_start, state->composition_end - state->composition_start);
+
+    if (m_imState & ImStateFlags::TextInputStateUpdated) {
+        m_imState = ImStateFlags::TextInputStateUpdated;
+        return;
+    }
+
+    // Ignore selection change triggered by ime composition unless it clears an actual text selection
+    if (state->composition_start != -1 && m_emptyPreviousSelection) {
+        m_imState = 0;
+        return;
+    }
+
+    m_imState |= ImStateFlags::TextInputStateUpdated;
+    if (m_imState == ImStateFlags::AllFlags)
+        selectionChanged();
+}
+
+void RenderWidgetHostViewQt::OnSelectionBoundsChanged(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view)
+{
+    Q_UNUSED(text_input_manager);
+    Q_UNUSED(updated_view);
+
+    m_imState |= ImStateFlags::TextSelectionBoundsUpdated;
+    if (m_imState == ImStateFlags::AllFlags)
+        selectionChanged();
+}
+
+void RenderWidgetHostViewQt::OnTextSelectionChanged(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view)
+{
+    Q_UNUSED(text_input_manager);
+    Q_UNUSED(updated_view);
 
 #if defined(USE_X11)
-    // Set the CLIPBOARD_TYPE_SELECTION to the ui::Clipboard.
-    ui::ScopedClipboardWriter clipboard_writer(ui::CLIPBOARD_TYPE_SELECTION);
-    clipboard_writer.WriteText(text);
-#endif
+    if (!GetSelectedText().empty()) {
+        // Set the CLIPBOARD_TYPE_SELECTION to the ui::Clipboard.
+        ui::ScopedClipboardWriter clipboard_writer(ui::CLIPBOARD_TYPE_SELECTION);
+        clipboard_writer.WriteText(GetSelectedText());
+    }
+#endif // defined(USE_X11)
+
+    m_imState |= ImStateFlags::TextSelectionUpdated;
+    if (m_imState == ImStateFlags::AllFlags)
+        selectionChanged();
+}
+
+void RenderWidgetHostViewQt::selectionChanged()
+{
+    // Reset input manager state
+    m_imState = 0;
+
+    const content::TextInputManager::TextSelection *selection = text_input_manager_->GetTextSelection();
+    if (!selection)
+        return;
+
+    if (!selection->range.IsValid())
+        return;
+
+    // Avoid duplicate empty selectionChanged() signals
+    if (GetSelectedText().empty() && m_emptyPreviousSelection) {
+        m_anchorPositionWithinSelection = m_cursorPosition;
+        m_cursorPositionWithinSelection = m_cursorPosition;
+        return;
+    }
+
+    uint newAnchorPositionWithinSelection = 0;
+    uint newCursorPositionWithinSelection = 0;
+
+    if (text_input_manager_->GetSelectionRegion()->anchor.type() == gfx::SelectionBound::RIGHT) {
+        newAnchorPositionWithinSelection = selection->range.GetMax() - selection->offset;
+        newCursorPositionWithinSelection = selection->range.GetMin() - selection->offset;
+    } else {
+        newAnchorPositionWithinSelection = selection->range.GetMin() - selection->offset;
+        newCursorPositionWithinSelection = selection->range.GetMax() - selection->offset;
+    }
+
+    if (m_anchorPositionWithinSelection == newAnchorPositionWithinSelection && m_cursorPositionWithinSelection == newCursorPositionWithinSelection)
+        return;
+
+    m_anchorPositionWithinSelection = newAnchorPositionWithinSelection;
+    m_cursorPositionWithinSelection = newCursorPositionWithinSelection;
+
+    if (!GetSelectedText().empty())
+        m_cursorPosition = newCursorPositionWithinSelection;
+
+    m_emptyPreviousSelection = GetSelectedText().empty();
+    m_adapterClient->selectionChanged();
 }
 
 void RenderWidgetHostViewQt::OnGestureEvent(const ui::GestureEventData& gesture)
@@ -820,34 +927,27 @@ QVariant RenderWidgetHostViewQt::inputMethodQuery(Qt::InputMethodQuery query)
 {
     switch (query) {
     case Qt::ImEnabled:
-        return QVariant(m_currentInputType != ui::TEXT_INPUT_TYPE_NONE);
+        return QVariant(getTextInputType() != ui::TEXT_INPUT_TYPE_NONE);
     case Qt::ImFont:
+        // TODO: Implement this
         return QVariant();
     case Qt::ImCursorRectangle:
-        // QIBusPlatformInputContext might query ImCursorRectangle before the
-        // RenderWidgetHostView is created. Without an available view GetSelectionRange()
-        // returns nullptr.
-        if (!GetTextInputManager()->GetSelectionRegion())
+        if (!text_input_manager_ || !text_input_manager_->GetActiveWidget())
             return QVariant();
-        return toQt(GetTextInputManager()->GetSelectionRegion()->caret_rect);
+        return toQt(text_input_manager_->GetSelectionRegion()->caret_rect);
     case Qt::ImCursorPosition:
-        Q_ASSERT(GetTextInputManager()->GetSelectionRegion());
-        return toQt(GetTextInputManager()->GetSelectionRegion()->focus.edge_top_rounded().x());
+        return m_cursorPosition;
     case Qt::ImAnchorPosition:
-        Q_ASSERT(GetTextInputManager()->GetSelectionRegion());
-        return toQt(GetTextInputManager()->GetSelectionRegion()->anchor.edge_top_rounded().x());
+        return GetSelectedText().empty() ? m_cursorPosition : m_anchorPositionWithinSelection;
     case Qt::ImSurroundingText:
         return m_surroundingText;
-    case Qt::ImCurrentSelection: {
-        Q_ASSERT(GetTextInputManager()->GetTextSelection());
-        base::string16 text;
-        GetTextInputManager()->GetTextSelection()->GetSelectedText(&text);
-        return toQt(text);
-    }
+    case Qt::ImCurrentSelection:
+        return toQt(GetSelectedText());
     case Qt::ImMaximumTextLength:
+        // TODO: Implement this
         return QVariant(); // No limit.
     case Qt::ImHints:
-        return int(toQtInputMethodHints(m_currentInputType));
+        return int(toQtInputMethodHints(getTextInputType()));
     default:
         return QVariant();
     }
@@ -1005,6 +1105,9 @@ void RenderWidgetHostViewQt::handleKeyEvent(QKeyEvent *ev)
 
 void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
 {
+    // Reset input manager state
+    m_imState = 0;
+
     if (!m_host)
         return;
 
@@ -1016,19 +1119,9 @@ void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
 
     const QList<QInputMethodEvent::Attribute> &attributes = ev->attributes();
     std::vector<blink::WebCompositionUnderline> underlines;
-    auto ensureValidSelectionRange = [&]() {
-        if (!selectionRange.IsValid()) {
-            // We did not receive a valid selection range, hence the range is going to mark the
-            // cursor position.
-            int newCursorPosition =
-                    (cursorPositionInPreeditString < 0) ? preeditString.length()
-                                                        : cursorPositionInPreeditString;
-            selectionRange.set_start(newCursorPosition);
-            selectionRange.set_end(newCursorPosition);
-        }
-    };
+    bool hasSelection = false;
 
-    Q_FOREACH (const QInputMethodEvent::Attribute &attribute, attributes) {
+    for (const auto &attribute : attributes) {
         switch (attribute.type) {
         case QInputMethodEvent::TextFormat: {
             if (preeditString.isEmpty())
@@ -1065,6 +1158,15 @@ void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
             cursorPositionInPreeditString = attribute.start;
             break;
         case QInputMethodEvent::Selection:
+            hasSelection = true;
+
+            // Cancel IME composition
+            if (preeditString.isEmpty() && attribute.start + attribute.length == 0) {
+                selectionRange.set_start(0);
+                selectionRange.set_end(0);
+                break;
+            }
+
             selectionRange.set_start(qMin(attribute.start, (attribute.start + attribute.length)));
             selectionRange.set_end(qMax(attribute.start, (attribute.start + attribute.length)));
             break;
@@ -1073,6 +1175,22 @@ void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
         }
     }
 
+    if (!selectionRange.IsValid()) {
+        // We did not receive a valid selection range, hence the range is going to mark the
+        // cursor position.
+        int newCursorPosition =
+                (cursorPositionInPreeditString < 0) ? preeditString.length()
+                                                    : cursorPositionInPreeditString;
+        selectionRange.set_start(newCursorPosition);
+        selectionRange.set_end(newCursorPosition);
+    }
+
+    if (hasSelection) {
+        content::RenderFrameHost *frameHost = getFocusedFrameHost();
+        if (frameHost)
+            frameHost->Send(new InputMsg_SetEditableSelectionOffsets(frameHost->GetRoutingID(), selectionRange.start(), selectionRange.end()));
+    }
+
     int replacementLength = ev->replacementLength();
     gfx::Range replacementRange = gfx::Range::InvalidRange();
 
@@ -1089,7 +1207,6 @@ void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
     }
 
     auto setCompositionString = [&](const QString &compositionString){
-        ensureValidSelectionRange();
         m_host->ImeSetComposition(toString16(compositionString),
                                   underlines,
                                   replacementRange,
@@ -1126,7 +1243,7 @@ void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
         // flickering in the textarea (or any other element).
         // Instead we postpone the processing of the empty QInputMethodEvent by posting it
         // to the same focused object, and cancelling the composition on the next event loop tick.
-        if (!m_receivedEmptyImeText && m_imeInProgress) {
+        if (!m_receivedEmptyImeText && m_imeInProgress && !hasSelection) {
             m_receivedEmptyImeText = true;
             m_imeInProgress = false;
             QInputMethodEvent *eventCopy = new QInputMethodEvent(*ev);
@@ -1304,4 +1421,26 @@ void RenderWidgetHostViewQt::OnBeginFrameSourcePausedChanged(bool paused)
     // begin frames.
 }
 
+content::RenderFrameHost *RenderWidgetHostViewQt::getFocusedFrameHost()
+{
+    content::RenderViewHostImpl *viewHost = content::RenderViewHostImpl::From(m_host);
+    if (!viewHost)
+        return nullptr;
+
+    content::FrameTreeNode *focusedFrame = viewHost->GetDelegate()->GetFrameTree()->GetFocusedFrame();
+    if (!focusedFrame)
+        return nullptr;
+
+    return focusedFrame->current_frame_host();
+}
+
+ui::TextInputType RenderWidgetHostViewQt::getTextInputType() const
+{
+    if (text_input_manager_ && text_input_manager_->GetTextInputState())
+        return text_input_manager_->GetTextInputState()->type;
+
+    return ui::TEXT_INPUT_TYPE_NONE;
+}
+
+
 } // namespace QtWebEngineCore
diff --git a/src/core/render_widget_host_view_qt.h b/src/core/render_widget_host_view_qt.h
index 1dae96a53..78b946a60 100644
--- a/src/core/render_widget_host_view_qt.h
+++ b/src/core/render_widget_host_view_qt.h
@@ -47,6 +47,7 @@
 #include "cc/resources/transferable_resource.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/renderer_host/render_widget_host_view_base.h"
+#include "content/browser/renderer_host/text_input_manager.h"
 #include "content/common/view_messages.h"
 #include "gpu/ipc/common/gpu_messages.h"
 #include "ui/events/gesture_detection/filtered_gesture_provider.h"
@@ -74,6 +75,7 @@ QT_END_NAMESPACE
 class WebContentsAdapterClient;
 
 namespace content {
+class RenderFrameHost;
 class RenderWidgetHostImpl;
 }
 
@@ -104,6 +106,7 @@ class RenderWidgetHostViewQt
 #ifndef QT_NO_ACCESSIBILITY
     , public QAccessible::ActivationObserver
 #endif // QT_NO_ACCESSIBILITY
+    , public content::TextInputManager::Observer
 {
 public:
     enum LoadVisuallyCommittedState {
@@ -140,7 +143,6 @@ public:
     virtual void UnlockMouse() Q_DECL_OVERRIDE;
     virtual void UpdateCursor(const content::WebCursor&) Q_DECL_OVERRIDE;
     virtual void SetIsLoading(bool) Q_DECL_OVERRIDE;
-    virtual void TextInputStateChanged(const content::TextInputState& params) Q_DECL_OVERRIDE;
     virtual void ImeCancelComposition() Q_DECL_OVERRIDE;
     virtual void ImeCompositionRangeChanged(const gfx::Range&, const std::vector<gfx::Rect>&) Q_DECL_OVERRIDE;
     virtual void RenderProcessGone(base::TerminationStatus, int) Q_DECL_OVERRIDE;
@@ -161,9 +163,6 @@ public:
     virtual void UnlockCompositingSurface() Q_DECL_OVERRIDE;
     virtual void SetNeedsBeginFrames(bool needs_begin_frames) Q_DECL_OVERRIDE;
 
-    // Overridden from RenderWidgetHostViewBase.
-    virtual void SelectionChanged(const base::string16 &text, size_t offset, const gfx::Range &range) Q_DECL_OVERRIDE;
-
     // Overridden from ui::GestureProviderClient.
     virtual void OnGestureEvent(const ui::GestureEventData& gesture) Q_DECL_OVERRIDE;
 
@@ -177,6 +176,11 @@ public:
     virtual bool forwardEvent(QEvent *) Q_DECL_OVERRIDE;
     virtual QVariant inputMethodQuery(Qt::InputMethodQuery query) Q_DECL_OVERRIDE;
 
+    // Overridden from content::TextInputManager::Observer
+    virtual void OnUpdateTextInputStateCalled(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view, bool did_update_state) Q_DECL_OVERRIDE;
+    virtual void OnSelectionBoundsChanged(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view) Q_DECL_OVERRIDE;
+    virtual void OnTextSelectionChanged(content::TextInputManager *text_input_manager, RenderWidgetHostViewBase *updated_view) Q_DECL_OVERRIDE;
+
     // cc::BeginFrameObserverBase implementation.
     bool OnBeginFrameDerivedImpl(const cc::BeginFrameArgs& args) override;
     void OnBeginFrameSourcePausedChanged(bool paused) override;
@@ -220,6 +224,10 @@ private:
 
     bool IsPopup() const;
 
+    void selectionChanged();
+    content::RenderFrameHost *getFocusedFrameHost();
+    ui::TextInputType getTextInputType() const;
+
     content::RenderWidgetHostImpl *m_host;
     ui::FilteredGestureProvider m_gestureProvider;
     base::TimeDelta m_eventsToNowDelta;
@@ -239,7 +247,6 @@ private:
     WebContentsAdapterClient *m_adapterClient;
     MultipleMouseClickHelper m_clickHelper;
 
-    ui::TextInputType m_currentInputType;
     bool m_imeInProgress;
     bool m_receivedEmptyImeText;
     QPoint m_previousMousePosition;
@@ -253,6 +260,11 @@ private:
     gfx::Vector2dF m_lastScrollOffset;
     gfx::SizeF m_lastContentsSize;
 
+    uint m_imState;
+    uint m_anchorPositionWithinSelection;
+    uint m_cursorPositionWithinSelection;
+    uint m_cursorPosition;
+    bool m_emptyPreviousSelection;
     QString m_surroundingText;
 };