Support IMM32 reconversion on Windows

content/browser/renderer_host/render_widget_host_view_win.cc

 // Copyright (c) 2011 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 "content/browser/renderer_host/render_widget_host_view_win.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/i18n/rtl.h"
@@ skipping 267 matching lines @@
       close_on_deactivate_(false),
       being_destroyed_(false),
       tooltip_hwnd_(NULL),
       tooltip_showing_(false),
       shutdown_factory_(this),
       parent_hwnd_(NULL),
       is_loading_(false),
       overlay_color_(0),
       text_input_type_(ui::TEXT_INPUT_TYPE_NONE),
       is_fullscreen_(false),
-      ignore_mouse_movement_(true) {
+      ignore_mouse_movement_(true),
+      composition_range_(ui::Range::InvalidRange()) {
   render_widget_host_->SetView(this);
   registrar_.Add(this,
                  content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
                  content::NotificationService::AllBrowserContextsAndSources());
 }
 
 RenderWidgetHostViewWin::~RenderWidgetHostViewWin() {
   UnlockMouse();
   ResetTooltip();
 }
@@ skipping 369 matching lines @@
       text_input_type_ != ui::TEXT_INPUT_TYPE_PASSWORD);
   // Only update caret position if the input method is enabled.
   if (is_enabled)
     ime_input_.UpdateCaretRect(m_hWnd, start_rect.Union(end_rect));
 }
 
 void RenderWidgetHostViewWin::ImeCancelComposition() {
   ime_input_.CancelIME(m_hWnd);
 }
 
+void RenderWidgetHostViewWin::ImeCompositionRangeChanged(
+    const ui::Range& range) {
+  composition_range_ = range;
+}
+
 BOOL CALLBACK EnumChildProc(HWND hwnd, LPARAM lparam) {
   if (!webkit::npapi::WebPluginDelegateImpl::IsPluginDelegateWindow(hwnd))
     return TRUE;
 
   gfx::Rect* rect = reinterpret_cast<gfx::Rect*>(lparam);
   static UINT msg = RegisterWindowMessage(webkit::npapi::kPaintMessageName);
   WPARAM wparam = rect->x() << 16 | rect->y();
   lparam = rect->width() << 16 | rect->height();
 
   // SendMessage gets the message across much quicker than PostMessage, since it
@@ skipping 584 matching lines @@
     // of the renderer process.
     render_widget_host_->ImeCancelComposition();
     ime_input_.ResetComposition(m_hWnd);
   }
   ime_input_.DestroyImeWindow(m_hWnd);
   // Let WTL call ::DefWindowProc() and release its resources.
   handled = FALSE;
   return 0;
 }
 
+LRESULT RenderWidgetHostViewWin::OnImeRequest(
+    UINT message, WPARAM wparam, LPARAM lparam, BOOL& handled) {
+  if (!render_widget_host_) {
+    handled = FALSE;
+    return 0;
+  }
+
+  // Should not receive WM_IME_REQUEST message, if IME is disabled.
+  if (text_input_type_ == ui::TEXT_INPUT_TYPE_NONE ||
+      text_input_type_ == ui::TEXT_INPUT_TYPE_PASSWORD) {
+    handled = FALSE;
+    return 0;
+  }
+
+  switch (wparam) {
+    case IMR_RECONVERTSTRING:
+      return OnReconvertString(reinterpret_cast<RECONVERTSTRING*>(lparam));
+    case IMR_DOCUMENTFEED:
+      return OnDocumentFeed(reinterpret_cast<RECONVERTSTRING*>(lparam));
+    default:
+      handled = FALSE;
+      return 0;
+  }
+}
+
 LRESULT RenderWidgetHostViewWin::OnMouseEvent(UINT message, WPARAM wparam,
                                               LPARAM lparam, BOOL& handled) {
   handled = TRUE;
 
   if (message == WM_MOUSELEAVE)
     ignore_mouse_movement_ = true;
 
   if (mouse_locked_) {
     HandleLockedMouseEvent(message, wparam, lparam);
     MoveCursorToCenter();
@@ skipping 727 matching lines @@
 
   if (message == WM_MOUSEMOVE) {
     CPoint center = GetClientCenter();
     // Ignore WM_MOUSEMOVE messages generated by MoveCursorToCenter().
     if (LOWORD(lparam) == center.x && HIWORD(lparam) == center.y)
       return;
   }
 
   ForwardMouseEventToRenderer(message, wparam, lparam);
 }
+
+LRESULT RenderWidgetHostViewWin::OnDocumentFeed(RECONVERTSTRING* reconv) {
+  size_t target_offset;
+  size_t target_length;
+  bool has_composition;
+  if (!composition_range_.is_empty()) {
+    target_offset = composition_range_.GetMin();
+    target_length = composition_range_.length();
+    has_composition = true;
+  } else if (selection_range_.IsValid()) {
+    target_offset = selection_range_.GetMin();
+    target_length = selection_range_.length();
+    has_composition = false;
+  } else {
+    return 0;
+  }
+
+  size_t len = selection_text_.length();
+  size_t need_size = sizeof(RECONVERTSTRING) + len * sizeof(WCHAR);
+
+  if (target_offset < selection_text_offset_ ||
+      target_offset + target_length > selection_text_offset_ + len) {
+    return 0;
+  }
+
+  if (!reconv)
+    return need_size;
+
+  if (reconv->dwSize < need_size)
+    return 0;
+
+  reconv->dwVersion = 0;
+  reconv->dwStrLen = len;
+  reconv->dwStrOffset = sizeof(RECONVERTSTRING);
+  reconv->dwCompStrLen = has_composition ? target_length: 0;
+  reconv->dwCompStrOffset =
+      (target_offset - selection_text_offset_) * sizeof(WCHAR);
+  reconv->dwTargetStrLen = target_length;
+  reconv->dwTargetStrOffset = reconv->dwCompStrOffset;
+  memcpy(reinterpret_cast<char*>(reconv) + sizeof(RECONVERTSTRING),
+         selection_text_.c_str(), len * sizeof(WCHAR));
+
+  // According to Microsft API document, IMR_RECONVERTSTRING and
+  // IMR_DOCUMENTFEED should return reconv, but some applications return
+  // need_size.
+  return reinterpret_cast<LRESULT>(reconv);
+}
+
+LRESULT RenderWidgetHostViewWin::OnReconvertString(RECONVERTSTRING* reconv) {
+  // If there is a composition string already, we don't allow reconversion.
+  if (ime_input_.is_composing())
+    return 0;
+
+  if (selection_range_.is_empty())
+    return 0;
+
+  if (selection_text_.empty())
+    return 0;
+
+  if (selection_range_.GetMin() < selection_text_offset_ ||
+      selection_range_.GetMax() >
+      selection_text_offset_ + selection_text_.length()) {
+    return 0;
+  }
+
+  size_t len = selection_range_.length();
+  size_t need_size = sizeof(RECONVERTSTRING) + len * sizeof(WCHAR);
+
+  if (!reconv)
+    return need_size;
+
+  if (reconv->dwSize < need_size)
+    return 0;
+
+  reconv->dwVersion = 0;
+  reconv->dwStrLen = len;
+  reconv->dwStrOffset = sizeof(RECONVERTSTRING);
+  reconv->dwCompStrLen = len;
+  reconv->dwCompStrOffset = 0;
+  reconv->dwTargetStrLen = len;
+  reconv->dwTargetStrOffset = 0;
+
+  size_t offset = selection_range_.GetMin() - selection_text_offset_;
+  memcpy(reinterpret_cast<char*>(reconv) + sizeof(RECONVERTSTRING),
+         selection_text_.c_str() + offset, len * sizeof(WCHAR));
+
+  // According to Microsft API document, IMR_RECONVERTSTRING and
+  // IMR_DOCUMENTFEED should return reconv, but some applications return
+  // need_size.
+  return reinterpret_cast<LRESULT>(reconv);
+}