Support TSF related event handling on NativeTextField

ui/base/ime/win/tsf_event_router.cc

Index: ui/base/ime/win/tsf_event_router.cc
diff --git a/ui/base/ime/win/tsf_event_router.cc b/ui/base/ime/win/tsf_event_router.cc
index 92e20f31ca5e53d3e0e7cdff3630e3685d1cc190..4cf625ecb16d3ce6d724e86fa430a82d8a949822 100644
--- a/ui/base/ime/win/tsf_event_router.cc
+++ b/ui/base/ime/win/tsf_event_router.cc
@@ -11,6 +11,7 @@
 #include "base/bind.h"
 #include "base/win/scoped_comptr.h"
 #include "base/win/metro.h"
+#include "ui/base/range/range.h"
 #include "ui/base/win/atl_module.h"
 
 namespace ui {
@@ -56,8 +57,9 @@ class ATL_NO_VTABLE TsfEventRouter::TsfEventRouterDelegate
   void SetRouter(TsfEventRouter* router);
 
  private:
-  // Returns true if the given |context| is composing.
-  static bool IsImeComposingInternal(ITfContext* context);
+  // Returns current composition range. Returns ui::Range::InvalidRange if there
+  // is no composition.
+  static ui::Range GetCompositionRange(ITfContext* context);
 
   // Returns true if the given |element_id| represents the candidate window.
   bool IsCandidateWindowInternal(DWORD element_id);
@@ -84,6 +86,7 @@ class ATL_NO_VTABLE TsfEventRouter::TsfEventRouterDelegate
   DWORD ui_source_cookie_;
 
   TsfEventRouter* router_;
+  ui::Range previous_composition_range_;
 
   DISALLOW_COPY_AND_ASSIGN(TsfEventRouterDelegate);
 };
@@ -91,7 +94,8 @@ class ATL_NO_VTABLE TsfEventRouter::TsfEventRouterDelegate
 TsfEventRouter::TsfEventRouterDelegate::TsfEventRouterDelegate()
     : context_source_cookie_(TF_INVALID_COOKIE),
       ui_source_cookie_(TF_INVALID_COOKIE),
-      router_(NULL) {
+      router_(NULL),
+      previous_composition_range_(ui::Range::InvalidRange()) {
 }
 
 TsfEventRouter::TsfEventRouterDelegate::~TsfEventRouterDelegate() {}
@@ -123,10 +127,20 @@ STDMETHODIMP TsfEventRouter::TsfEventRouterDelegate::OnEndEdit(
   if (FAILED(ranges->Next(1, range.Receive(), &fetched_count)))
     return S_OK;  // Don't care about failures.
 
+  const ui::Range composition_range = GetCompositionRange(context);
+
+  if (!previous_composition_range_.IsValid() && composition_range.IsValid())
+    router_->OnTsfStartComposition();
+
   // |fetched_count| != 0 means there is at least one range that contains
   // updated text.
   if (fetched_count != 0)
-    router_->OnTextUpdated();
+    router_->OnTextUpdated(composition_range);
+
+  if (previous_composition_range_.IsValid() && !composition_range.IsValid())
+    router_->OnTsfEndComposition();
+
+  previous_composition_range_ = composition_range;
   return S_OK;
 }
 
@@ -198,23 +212,39 @@ void TsfEventRouter::TsfEventRouterDelegate::SetManager(
 }
 
 bool TsfEventRouter::TsfEventRouterDelegate::IsImeComposing() {
-  return context_ && IsImeComposingInternal(context_);
+  return context_ && GetCompositionRange(context_).IsValid();
 }
 
 // static
-bool TsfEventRouter::TsfEventRouterDelegate::IsImeComposingInternal(
+ui::Range TsfEventRouter::TsfEventRouterDelegate::GetCompositionRange(
     ITfContext* context) {
   DCHECK(context);
   base::win::ScopedComPtr<ITfContextComposition> context_composition;
   if (FAILED(context_composition.QueryFrom(context)))
-    return false;
+    return ui::Range::InvalidRange();
   base::win::ScopedComPtr<IEnumITfCompositionView> enum_composition_view;
   if (FAILED(context_composition->EnumCompositions(
       enum_composition_view.Receive())))
-    return false;
+    return ui::Range::InvalidRange();
   base::win::ScopedComPtr<ITfCompositionView> composition_view;
-  return enum_composition_view->Next(1, composition_view.Receive(),
-                                     NULL) == S_OK;
+  if (enum_composition_view->Next(1, composition_view.Receive(),
+                                  NULL) != S_OK)
+    return ui::Range::InvalidRange();
+
+  base::win::ScopedComPtr<ITfRange> range;
+  if (FAILED(composition_view->GetRange(range.Receive())))
+    return ui::Range::InvalidRange();
+
+  base::win::ScopedComPtr<ITfRangeACP> range_acp;
+  if (FAILED(range_acp.QueryFrom(range)))
+    return ui::Range::InvalidRange();
+
+  LONG start = 0;
+  LONG length = 0;
+  if (FAILED(range_acp->GetExtent(&start, &length)))
+    return ui::Range::InvalidRange();
+
+  return ui::Range(start, start + length);
 }
 
 bool TsfEventRouter::TsfEventRouterDelegate::IsCandidateWindowInternal(
@@ -254,20 +284,28 @@ TsfEventRouter::~TsfEventRouter() {
   }
 }
 
-void TsfEventRouter::SetManager(ITfThreadMgr* thread_manager) {
-  delegate_->SetManager(thread_manager);
-}
-
 bool TsfEventRouter::IsImeComposing() {
   return delegate_->IsImeComposing();
 }
 
-void TsfEventRouter::OnTextUpdated() {
-  observer_->OnTextUpdated();
-}
-
 void TsfEventRouter::OnCandidateWindowCountChanged(size_t window_count) {
   observer_->OnCandidateWindowCountChanged(window_count);
 }
 
+void TsfEventRouter::OnTsfStartComposition() {
+  observer_->OnTsfStartComposition();
+}
+
+void TsfEventRouter::OnTextUpdated(const ui::Range& composition_range) {
+  observer_->OnTextUpdated(composition_range);
+}
+
+void TsfEventRouter::OnTsfEndComposition() {
+  observer_->OnTsfEndComposition();
+}
+
+void TsfEventRouter::SetManager(ITfThreadMgr* thread_manager) {
+  delegate_->SetManager(thread_manager);
+}
+
 }  // namespace ui