1 files changed, 462 insertions, 0 deletions
diff --git a/accessible/base/FocusManager.cpp b/accessible/base/FocusManager.cpp
new file mode 100644
index 0000000000..57cfd7034e
--- /dev/null
+++ b/accessible/base/FocusManager.cpp
@@ -0,0 +1,462 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "FocusManager.h"
+
+#include "LocalAccessible-inl.h"
+#include "DocAccessible-inl.h"
+#include "nsAccessibilityService.h"
+#include "nsEventShell.h"
+
+#include "nsFocusManager.h"
+#include "mozilla/a11y/DocAccessibleParent.h"
+#include "mozilla/EventStateManager.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/BrowsingContext.h"
+#include "mozilla/dom/BrowserParent.h"
+
+namespace mozilla {
+namespace a11y {
+
+FocusManager::FocusManager() {}
+
+FocusManager::~FocusManager() {}
+
+LocalAccessible* FocusManager::FocusedLocalAccessible() const {
+  MOZ_ASSERT(NS_IsMainThread());
+  if (mActiveItem) {
+    if (mActiveItem->IsDefunct()) {
+      MOZ_ASSERT_UNREACHABLE("Stored active item is unbound from document");
+      return nullptr;
+    }
+
+    return mActiveItem;
+  }
+
+  if (nsAccessibilityService::IsShutdown()) {
+    // We might try to get or create a DocAccessible below, which isn't safe (or
+    // useful) if the accessibility service is shutting down.
+    return nullptr;
+  }
+
+  nsINode* focusedNode = FocusedDOMNode();
+  if (focusedNode) {
+    DocAccessible* doc =
+        GetAccService()->GetDocAccessible(focusedNode->OwnerDoc());
+    return doc ? doc->GetAccessibleEvenIfNotInMapOrContainer(focusedNode)
+               : nullptr;
+  }
+
+  return nullptr;
+}
+
+Accessible* FocusManager::FocusedAccessible() const {
+#if defined(ANDROID)
+  // It's not safe to call FocusedLocalAccessible() except on the main thread.
+  // Android might query RemoteAccessibles on the UI thread, which might call
+  // FocusedAccessible(). Never try to get the focused LocalAccessible in this
+  // case.
+  if (NS_IsMainThread()) {
+    if (Accessible* focusedAcc = FocusedLocalAccessible()) {
+      return focusedAcc;
+    }
+  } else {
+    nsAccessibilityService::GetAndroidMonitor().AssertCurrentThreadOwns();
+  }
+  return mFocusedRemoteDoc ? mFocusedRemoteDoc->GetFocusedAcc() : nullptr;
+#else
+  if (Accessible* focusedAcc = FocusedLocalAccessible()) {
+    return focusedAcc;
+  }
+
+  if (!XRE_IsParentProcess()) {
+    // DocAccessibleParent's don't exist in the content
+    // process, so we can't return anything useful if this
+    // is the case.
+    return nullptr;
+  }
+
+  nsFocusManager* focusManagerDOM = nsFocusManager::GetFocusManager();
+  if (!focusManagerDOM) {
+    return nullptr;
+  }
+
+  // If we call GetFocusedBrowsingContext from the chrome process
+  // it returns the BrowsingContext for the focused _window_, which
+  // is not helpful here. Instead use GetFocusedBrowsingContextInChrome
+  // which returns the content BrowsingContext that has focus.
+  dom::BrowsingContext* focusedContext =
+      focusManagerDOM->GetFocusedBrowsingContextInChrome();
+
+  DocAccessibleParent* focusedDoc =
+      DocAccessibleParent::GetFrom(focusedContext);
+  return focusedDoc ? focusedDoc->GetFocusedAcc() : nullptr;
+#endif  // defined(ANDROID)
+}
+
+bool FocusManager::IsFocusWithin(const Accessible* aContainer) const {
+  Accessible* child = FocusedAccessible();
+  while (child) {
+    if (child == aContainer) return true;
+
+    child = child->Parent();
+  }
+  return false;
+}
+
+FocusManager::FocusDisposition FocusManager::IsInOrContainsFocus(
+    const LocalAccessible* aAccessible) const {
+  LocalAccessible* focus = FocusedLocalAccessible();
+  if (!focus) return eNone;
+
+  // If focused.
+  if (focus == aAccessible) return eFocused;
+
+  // If contains the focus.
+  LocalAccessible* child = focus->LocalParent();
+  while (child) {
+    if (child == aAccessible) return eContainsFocus;
+
+    child = child->LocalParent();
+  }
+
+  // If contained by focus.
+  child = aAccessible->LocalParent();
+  while (child) {
+    if (child == focus) return eContainedByFocus;
+
+    child = child->LocalParent();
+  }
+
+  return eNone;
+}
+
+bool FocusManager::WasLastFocused(const LocalAccessible* aAccessible) const {
+  return mLastFocus == aAccessible;
+}
+
+void FocusManager::NotifyOfDOMFocus(nsISupports* aTarget) {
+#ifdef A11Y_LOG
+  if (logging::IsEnabled(logging::eFocus)) {
+    logging::FocusNotificationTarget("DOM focus", "Target", aTarget);
+  }
+#endif
+
+  mActiveItem = nullptr;
+
+  nsCOMPtr<nsINode> targetNode(do_QueryInterface(aTarget));
+  if (targetNode) {
+    DocAccessible* document =
+        GetAccService()->GetDocAccessible(targetNode->OwnerDoc());
+    if (document) {
+      // Set selection listener for focused element.
+      if (targetNode->IsElement()) {
+        SelectionMgr()->SetControlSelectionListener(targetNode->AsElement());
+      }
+
+      document->HandleNotification<FocusManager, nsINode>(
+          this, &FocusManager::ProcessDOMFocus, targetNode);
+    }
+  }
+}
+
+void FocusManager::NotifyOfDOMBlur(nsISupports* aTarget) {
+#ifdef A11Y_LOG
+  if (logging::IsEnabled(logging::eFocus)) {
+    logging::FocusNotificationTarget("DOM blur", "Target", aTarget);
+  }
+#endif
+
+  mActiveItem = nullptr;
+
+  // If DOM document stays focused then fire accessible focus event to process
+  // the case when no element within this DOM document will be focused.
+  nsCOMPtr<nsINode> targetNode(do_QueryInterface(aTarget));
+  if (targetNode && targetNode->OwnerDoc() == FocusedDOMDocument()) {
+    dom::Document* DOMDoc = targetNode->OwnerDoc();
+    DocAccessible* document = GetAccService()->GetDocAccessible(DOMDoc);
+    if (document) {
+      // Clear selection listener for previously focused element.
+      if (targetNode->IsElement()) {
+        SelectionMgr()->ClearControlSelectionListener();
+      }
+
+      document->HandleNotification<FocusManager, nsINode>(
+          this, &FocusManager::ProcessDOMFocus, DOMDoc);
+    }
+  }
+}
+
+void FocusManager::ActiveItemChanged(LocalAccessible* aItem,
+                                     bool aCheckIfActive) {
+#ifdef A11Y_LOG
+  if (logging::IsEnabled(logging::eFocus)) {
+    logging::FocusNotificationTarget("active item changed", "Item", aItem);
+  }
+#endif
+
+  // Nothing changed, happens for XUL trees and HTML selects.
+  if (aItem && aItem == mActiveItem) {
+    return;
+  }
+
+  mActiveItem = nullptr;
+
+  if (aItem && aCheckIfActive) {
+    LocalAccessible* widget = aItem->ContainerWidget();
+#ifdef A11Y_LOG
+    if (logging::IsEnabled(logging::eFocus)) logging::ActiveWidget(widget);
+#endif
+    if (!widget || !widget->IsActiveWidget() || !widget->AreItemsOperable()) {
+      return;
+    }
+  }
+  mActiveItem = aItem;
+
+  // If mActiveItem is null we may need to shift a11y focus back to a remote
+  // document. For example, when combobox popup is closed, then
+  // the focus should be moved back to the combobox.
+  if (!mActiveItem && XRE_IsParentProcess()) {
+    dom::BrowserParent* browser = dom::BrowserParent::GetFocused();
+    if (browser) {
+      a11y::DocAccessibleParent* dap = browser->GetTopLevelDocAccessible();
+      if (dap) {
+        Unused << dap->SendRestoreFocus();
+      }
+    }
+  }
+
+  // If active item is changed then fire accessible focus event on it, otherwise
+  // if there's no an active item then fire focus event to accessible having
+  // DOM focus.
+  LocalAccessible* target = FocusedLocalAccessible();
+  if (target) {
+    DispatchFocusEvent(target->Document(), target);
+  }
+}
+
+void FocusManager::ForceFocusEvent() {
+  nsINode* focusedNode = FocusedDOMNode();
+  if (focusedNode) {
+    DocAccessible* document =
+        GetAccService()->GetDocAccessible(focusedNode->OwnerDoc());
+    if (document) {
+      document->HandleNotification<FocusManager, nsINode>(
+          this, &FocusManager::ProcessDOMFocus, focusedNode);
+    }
+  }
+}
+
+void FocusManager::DispatchFocusEvent(DocAccessible* aDocument,
+                                      LocalAccessible* aTarget) {
+  MOZ_ASSERT(aDocument, "No document for focused accessible!");
+  if (aDocument) {
+    RefPtr<AccEvent> event =
+        new AccEvent(nsIAccessibleEvent::EVENT_FOCUS, aTarget, eAutoDetect,
+                     AccEvent::eCoalesceOfSameType);
+    aDocument->FireDelayedEvent(event);
+    mLastFocus = aTarget;
+    if (mActiveItem != aTarget) {
+      // This new focus overrides the stored active item, so clear the active
+      // item. Among other things, the old active item might die.
+      mActiveItem = nullptr;
+    }
+
+#ifdef A11Y_LOG
+    if (logging::IsEnabled(logging::eFocus)) logging::FocusDispatched(aTarget);
+#endif
+  }
+}
+
+void FocusManager::ProcessDOMFocus(nsINode* aTarget) {
+#ifdef A11Y_LOG
+  if (logging::IsEnabled(logging::eFocus)) {
+    logging::FocusNotificationTarget("process DOM focus", "Target", aTarget);
+  }
+#endif
+
+  DocAccessible* document =
+      GetAccService()->GetDocAccessible(aTarget->OwnerDoc());
+  if (!document) return;
+
+  LocalAccessible* target =
+      document->GetAccessibleEvenIfNotInMapOrContainer(aTarget);
+  if (target) {
+    // Check if still focused. Otherwise we can end up with storing the active
+    // item for control that isn't focused anymore.
+    nsINode* focusedNode = FocusedDOMNode();
+    if (!focusedNode) return;
+
+    LocalAccessible* DOMFocus =
+        document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
+    if (target != DOMFocus) return;
+
+    LocalAccessible* activeItem = target->CurrentItem();
+    if (activeItem) {
+      mActiveItem = activeItem;
+      target = activeItem;
+    }
+
+    DispatchFocusEvent(document, target);
+  }
+}
+
+void FocusManager::ProcessFocusEvent(AccEvent* aEvent) {
+  MOZ_ASSERT(aEvent->GetEventType() == nsIAccessibleEvent::EVENT_FOCUS,
+             "Focus event is expected!");
+
+  // Emit focus event if event target is the active item. Otherwise then check
+  // if it's still focused and then update active item and emit focus event.
+  LocalAccessible* target = aEvent->GetAccessible();
+  MOZ_ASSERT(!target->IsDefunct());
+  if (target != mActiveItem) {
+    // Check if still focused. Otherwise we can end up with storing the active
+    // item for control that isn't focused anymore.
+    DocAccessible* document = aEvent->Document();
+    nsINode* focusedNode = FocusedDOMNode();
+    if (!focusedNode) return;
+
+    LocalAccessible* DOMFocus =
+        document->GetAccessibleEvenIfNotInMapOrContainer(focusedNode);
+    if (target != DOMFocus) return;
+
+    LocalAccessible* activeItem = target->CurrentItem();
+    if (activeItem) {
+      mActiveItem = activeItem;
+      target = activeItem;
+      MOZ_ASSERT(!target->IsDefunct());
+    }
+  }
+
+  // Fire menu start/end events for ARIA menus.
+  if (target->IsARIARole(nsGkAtoms::menuitem)) {
+    // The focus was moved into menu.
+    LocalAccessible* ARIAMenubar = nullptr;
+    for (LocalAccessible* parent = target->LocalParent(); parent;
+         parent = parent->LocalParent()) {
+      if (parent->IsARIARole(nsGkAtoms::menubar)) {
+        ARIAMenubar = parent;
+        break;
+      }
+
+      // Go up in the parent chain of the menu hierarchy.
+      if (!parent->IsARIARole(nsGkAtoms::menuitem) &&
+          !parent->IsARIARole(nsGkAtoms::menu)) {
+        break;
+      }
+    }
+
+    if (ARIAMenubar != mActiveARIAMenubar) {
+      // Leaving ARIA menu. Fire menu_end event on current menubar.
+      if (mActiveARIAMenubar) {
+        RefPtr<AccEvent> menuEndEvent =
+            new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
+                         aEvent->FromUserInput());
+        nsEventShell::FireEvent(menuEndEvent);
+      }
+
+      mActiveARIAMenubar = ARIAMenubar;
+
+      // Entering ARIA menu. Fire menu_start event.
+      if (mActiveARIAMenubar) {
+        RefPtr<AccEvent> menuStartEvent =
+            new AccEvent(nsIAccessibleEvent::EVENT_MENU_START,
+                         mActiveARIAMenubar, aEvent->FromUserInput());
+        nsEventShell::FireEvent(menuStartEvent);
+      }
+    }
+  } else if (mActiveARIAMenubar) {
+    // Focus left a menu. Fire menu_end event.
+    RefPtr<AccEvent> menuEndEvent =
+        new AccEvent(nsIAccessibleEvent::EVENT_MENU_END, mActiveARIAMenubar,
+                     aEvent->FromUserInput());
+    nsEventShell::FireEvent(menuEndEvent);
+
+    mActiveARIAMenubar = nullptr;
+  }
+
+#ifdef A11Y_LOG
+  if (logging::IsEnabled(logging::eFocus)) {
+    logging::FocusNotificationTarget("fire focus event", "Target", target);
+  }
+#endif
+
+  // Reset cached caret value. The cache will be updated upon processing the
+  // next caret move event. This ensures that we will return the correct caret
+  // offset before the caret move event is handled.
+  SelectionMgr()->ResetCaretOffset();
+
+  RefPtr<AccEvent> focusEvent = new AccEvent(nsIAccessibleEvent::EVENT_FOCUS,
+                                             target, aEvent->FromUserInput());
+  nsEventShell::FireEvent(focusEvent);
+
+  if (NS_WARN_IF(target->IsDefunct())) {
+    // target died during nsEventShell::FireEvent.
+    return;
+  }
+
+  // Fire scrolling_start event when the document receives the focus if it has
+  // an anchor jump. If an accessible within the document receive the focus
+  // then null out the anchor jump because it no longer applies.
+  DocAccessible* targetDocument = target->Document();
+  MOZ_ASSERT(targetDocument);
+  LocalAccessible* anchorJump = targetDocument->AnchorJump();
+  if (anchorJump) {
+    if (target == targetDocument || target->IsNonInteractive()) {
+      // XXX: bug 625699, note in some cases the node could go away before we
+      // we receive focus event, for example if the node is removed from DOM.
+      nsEventShell::FireEvent(nsIAccessibleEvent::EVENT_SCROLLING_START,
+                              anchorJump, aEvent->FromUserInput());
+    }
+    targetDocument->SetAnchorJump(nullptr);
+  }
+}
+
+nsINode* FocusManager::FocusedDOMNode() const {
+  nsFocusManager* DOMFocusManager = nsFocusManager::GetFocusManager();
+  nsIContent* focusedElm = DOMFocusManager->GetFocusedElement();
+  nsIFrame* focusedFrame = focusedElm ? focusedElm->GetPrimaryFrame() : nullptr;
+  // DOM elements retain their focused state when they get styled as display:
+  // none/content or visibility: hidden. We should treat those cases as if those
+  // elements were removed, and focus on doc.
+  if (focusedFrame && focusedFrame->StyleVisibility()->IsVisible()) {
+    // Print preview documents don't get DocAccessibles, but we still want a11y
+    // focus to go somewhere useful. Therefore, we allow a11y focus to land on
+    // the OuterDocAccessible in this case.
+    // Note that this code only handles remote print preview documents.
+    if (EventStateManager::IsTopLevelRemoteTarget(focusedElm) &&
+        focusedElm->AsElement()->HasAttribute(u"printpreview"_ns)) {
+      return focusedElm;
+    }
+    // No focus on remote target elements like xul:browser having DOM focus and
+    // residing in chrome process because it means an element in content process
+    // keeps the focus. Similarly, suppress focus on OOP iframes because an
+    // element in another content process should now have the focus.
+    if (EventStateManager::IsRemoteTarget(focusedElm)) {
+      return nullptr;
+    }
+    return focusedElm;
+  }
+
+  // Otherwise the focus can be on DOM document.
+  dom::BrowsingContext* context = DOMFocusManager->GetFocusedBrowsingContext();
+  if (context) {
+    // GetDocShell will return null if the document isn't in our process.
+    nsIDocShell* shell = context->GetDocShell();
+    if (shell) {
+      return shell->GetDocument();
+    }
+  }
+
+  // Focus isn't in this process.
+  return nullptr;
+}
+
+dom::Document* FocusManager::FocusedDOMDocument() const {
+  nsINode* focusedNode = FocusedDOMNode();
+  return focusedNode ? focusedNode->OwnerDoc() : nullptr;
+}
+
+}  // namespace a11y
+}  // namespace mozilla