gecko-dev/accessible/src/base/nsRootAccessible.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
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 *
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 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
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 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
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 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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 * the provisions above, a recipient may use your version of this file under
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 * ***** END LICENSE BLOCK ***** */

// NOTE: alphabetically ordered
#include "nsAccessibilityService.h"
#include "nsAccessibleEventData.h"
#include "nsCaretAccessible.h"
#include "nsHTMLSelectAccessible.h"
#include "nsIAccessibleCaret.h"
#include "nsIChromeEventHandler.h"
#include "nsIDOMElement.h"
#include "nsIDOMEventListener.h"
#include "nsIDOMEventTarget.h"
#include "nsIDOMHTMLAnchorElement.h"
#include "nsIDOMHTMLInputElement.h"
#include "nsIDOMHTMLSelectElement.h"
#include "nsIDOMNSEvent.h"
#include "nsIDOMWindow.h"
#include "nsIDOMXULMenuListElement.h"
#include "nsIDOMXULMultSelectCntrlEl.h"
#include "nsIDOMXULSelectCntrlItemEl.h"
#include "nsIDocument.h"
#include "nsIEventListenerManager.h"
#include "nsIHTMLDocument.h"
#include "nsIFocusController.h"
#include "nsIFrame.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsIScriptGlobalObject.h"
#include "nsIScrollableView.h"
#include "nsIServiceManager.h"
#include "nsIViewManager.h"
#include "nsLayoutAtoms.h"
#include "nsPIDOMWindow.h"
#include "nsReadableUtils.h"
#include "nsRootAccessible.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsIDocShellTreeOwner.h"
#include "nsIBaseWindow.h"

#ifdef MOZ_XUL
#include "nsXULTreeAccessible.h"
#include "nsIXULDocument.h"
#endif
#include "nsAccessibilityService.h"
#include "nsISelectionPrivate.h"
#include "nsICaret.h"
#include "nsIDOMHTMLInputElement.h"
#include "nsAccessibleEventData.h"
#include "nsIDOMDocument.h"

#ifdef MOZ_ACCESSIBILITY_ATK
#include "nsIAccessibleHyperText.h"
#endif

NS_INTERFACE_MAP_BEGIN(nsRootAccessible)
  NS_INTERFACE_MAP_ENTRY(nsIDOMFocusListener)
  NS_INTERFACE_MAP_ENTRY(nsIDOMFormListener)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMFormListener)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIDOMEventListener, nsIDOMFormListener)
NS_INTERFACE_MAP_END_INHERITING(nsDocAccessible)

NS_IMPL_ADDREF_INHERITED(nsRootAccessible, nsDocAccessible)
NS_IMPL_RELEASE_INHERITED(nsRootAccessible, nsDocAccessible)


//-----------------------------------------------------
// construction 
//-----------------------------------------------------
nsRootAccessible::nsRootAccessible(nsIDOMNode *aDOMNode, nsIWeakReference* aShell):
  nsDocAccessibleWrap(aDOMNode, aShell), 
  mAccService(do_GetService("@mozilla.org/accessibilityService;1"))
{
}

//-----------------------------------------------------
// destruction
//-----------------------------------------------------
nsRootAccessible::~nsRootAccessible()
{
}

// helpers
/* readonly attribute AString name; */
NS_IMETHODIMP nsRootAccessible::GetName(nsAString& aName)
{
  if (!mDocument) {
    return NS_ERROR_FAILURE;
  }

  if (mRoleMapEntry) {
    nsAccessible::GetName(aName);
    if (!aName.IsEmpty()) {
      return NS_OK;
    }
  }

  nsIScriptGlobalObject *globalScript = mDocument->GetScriptGlobalObject();
  nsIDocShell *docShell = nsnull;
  if (globalScript) {
    docShell = globalScript->GetDocShell();
  }

  nsCOMPtr<nsIDocShellTreeItem> docShellAsItem(do_QueryInterface(docShell));
  if(!docShellAsItem)
     return NS_ERROR_FAILURE;

  nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
  docShellAsItem->GetTreeOwner(getter_AddRefs(treeOwner));

  nsCOMPtr<nsIBaseWindow> baseWindow(do_QueryInterface(treeOwner));
  if (baseWindow) {
    nsXPIDLString title;
    baseWindow->GetTitle(getter_Copies(title));
    aName.Assign(title);
    return NS_OK;
  }

  return NS_ERROR_FAILURE;
}

/* readonly attribute nsIAccessible accParent; */
NS_IMETHODIMP nsRootAccessible::GetParent(nsIAccessible * *aParent) 
{ 
  *aParent = nsnull;
  return NS_OK;
}

/* readonly attribute unsigned long accRole; */
NS_IMETHODIMP nsRootAccessible::GetRole(PRUint32 *aRole) 
{ 
  if (!mDocument) {
    return NS_ERROR_FAILURE;
  }

  // If it's a <dialog> or <wizard>, use ROLE_DIALOG instead
  nsIContent *rootContent = mDocument->GetRootContent();
  if (rootContent) {
    nsCOMPtr<nsIDOMElement> rootElement(do_QueryInterface(rootContent));
    if (rootElement) {
      nsAutoString name;
      rootElement->GetLocalName(name);
      if (name.EqualsLiteral("dialog") || name.EqualsLiteral("wizard")) {
        *aRole = ROLE_DIALOG; // Always at the root
        return NS_OK;
      }
    }
  }

  return nsDocAccessibleWrap::GetRole(aRole);
}

NS_IMETHODIMP nsRootAccessible::GetState(PRUint32 *aState) 
{
  nsresult rv = NS_ERROR_FAILURE;
  if (mDOMNode) {
    rv = nsDocAccessibleWrap::GetState(aState);
  }
  if (NS_FAILED(rv)) {
    return rv;
  }

  NS_ASSERTION(mDocument, "mDocument should not be null unless mDOMNode is");
  if (gLastFocusedNode) {
    nsCOMPtr<nsIDOMDocument> rootAccessibleDoc(do_QueryInterface(mDocument));
    nsCOMPtr<nsIDOMDocument> focusedDoc;
    gLastFocusedNode->GetOwnerDocument(getter_AddRefs(focusedDoc));
    if (rootAccessibleDoc == focusedDoc) {
      *aState |= STATE_FOCUSED;
    }
  }
  return NS_OK;
}

void
nsRootAccessible::GetChromeEventHandler(nsIDOMEventTarget **aChromeTarget)
{
  nsCOMPtr<nsIDOMWindow> domWin;
  GetWindow(getter_AddRefs(domWin));
  nsCOMPtr<nsPIDOMWindow> privateDOMWindow(do_QueryInterface(domWin));
  nsCOMPtr<nsIChromeEventHandler> chromeEventHandler;
  if (privateDOMWindow) {
    chromeEventHandler = privateDOMWindow->GetChromeEventHandler();
  }

  nsCOMPtr<nsIDOMEventTarget> target(do_QueryInterface(chromeEventHandler));

  *aChromeTarget = target;
  NS_IF_ADDREF(*aChromeTarget);
}

nsresult nsRootAccessible::AddEventListeners()
{
  // use AddEventListener from the nsIDOMEventTarget interface
  nsCOMPtr<nsIDOMEventTarget> target(do_QueryInterface(mDocument));
  if (target) { 
    // capture DOM focus events 
    nsresult rv = target->AddEventListener(NS_LITERAL_STRING("focus"), NS_STATIC_CAST(nsIDOMFocusListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // capture Form change events 
    rv = target->AddEventListener(NS_LITERAL_STRING("select"), NS_STATIC_CAST(nsIDOMFormListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // capture ValueChange events (fired whenever value changes, immediately after, whether focus moves or not)
    rv = target->AddEventListener(NS_LITERAL_STRING("ValueChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // capture AlertActive events (fired whenever alert pops up)
    rv = target->AddEventListener(NS_LITERAL_STRING("AlertActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // add ourself as a OpenStateChange listener (custom event fired in tree.xml)
    rv = target->AddEventListener(NS_LITERAL_STRING("OpenStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // add ourself as a CheckboxStateChange listener (custom event fired in nsHTMLInputElement.cpp)
    rv = target->AddEventListener(NS_LITERAL_STRING("CheckboxStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    // add ourself as a RadioStateChange Listener ( custom event fired in in nsHTMLInputElement.cpp  & radio.xml)
    rv = target->AddEventListener(NS_LITERAL_STRING("RadioStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    rv = target->AddEventListener(NS_LITERAL_STRING("popupshown"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    rv = target->AddEventListener(NS_LITERAL_STRING("popuphiding"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    rv = target->AddEventListener(NS_LITERAL_STRING("DOMMenuInactive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");

    rv = target->AddEventListener(NS_LITERAL_STRING("DOMMenuItemActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
    
    rv = target->AddEventListener(NS_LITERAL_STRING("DOMMenuBarActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
    
    rv = target->AddEventListener(NS_LITERAL_STRING("DOMMenuBarInactive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    NS_ASSERTION(NS_SUCCEEDED(rv), "failed to register listener");
  }

  GetChromeEventHandler(getter_AddRefs(target));
  NS_ASSERTION(target, "No chrome event handler for document");
  if (target) {   
    // onunload doesn't fire unless we use chrome event handler for target
    target->AddEventListener(NS_LITERAL_STRING("unload"), 
                             NS_STATIC_CAST(nsIDOMXULListener*, this), 
                             PR_TRUE);
    target->AddEventListener(NS_LITERAL_STRING("load"), 
                             NS_STATIC_CAST(nsIDOMXULListener*, this), 
                             PR_TRUE);
  }

  if (!mCaretAccessible)
    mCaretAccessible = new nsCaretAccessible(mDOMNode, mWeakShell, this);

  // Fire accessible focus event for pre-existing focus, but wait until all internal
  // focus events are finished for window initialization.
  mFireFocusTimer = do_CreateInstance("@mozilla.org/timer;1");
  if (mFireFocusTimer) {
    mFireFocusTimer->InitWithFuncCallback(FireFocusCallback, this,
                                          0, nsITimer::TYPE_ONE_SHOT);
  }

  return nsDocAccessible::AddEventListeners();
}

nsresult nsRootAccessible::RemoveEventListeners()
{
  nsCOMPtr<nsIDOMEventTarget> target(do_QueryInterface(mDocument));
  if (target) { 
    target->RemoveEventListener(NS_LITERAL_STRING("focus"), NS_STATIC_CAST(nsIDOMFocusListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("select"), NS_STATIC_CAST(nsIDOMFormListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("ValueChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("AlertActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("OpenStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("CheckboxStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("RadioStateChange"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("popupshown"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("popuphiding"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("DOMMenuInactive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("DOMMenuItemActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("DOMMenuBarActive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("DOMMenuBarInactive"), NS_STATIC_CAST(nsIDOMXULListener*, this), PR_TRUE);
  }

  GetChromeEventHandler(getter_AddRefs(target));
  if (target) {
    target->RemoveEventListener(NS_LITERAL_STRING("unload"), 
                                NS_STATIC_CAST(nsIDOMXULListener*, this), 
                                PR_TRUE);
    target->RemoveEventListener(NS_LITERAL_STRING("load"), 
                                NS_STATIC_CAST(nsIDOMXULListener*, this), 
                                PR_TRUE);
  }

  if (mCaretAccessible) {
    mCaretAccessible->RemoveSelectionListener();
    mCaretAccessible = nsnull;
  }

  mAccService = nsnull;

  return nsDocAccessible::RemoveEventListeners();
}

NS_IMETHODIMP nsRootAccessible::GetCaretAccessible(nsIAccessible **aCaretAccessible)
{
  *aCaretAccessible = nsnull;
  if (mCaretAccessible) {
    CallQueryInterface(mCaretAccessible, aCaretAccessible);
  }

  return NS_OK;
}

void nsRootAccessible::FireAccessibleFocusEvent(nsIAccessible *aAccessible, nsIDOMNode *aNode)
{
  NS_ASSERTION(aAccessible, "Attempted to fire focus event for no accessible");
  PRUint32 role = ROLE_NOTHING;
  aAccessible->GetFinalRole(&role);

  // Fire focus if it changes, but always fire focus events for menu items
  if (gLastFocusedNode == aNode && role != ROLE_MENUITEM) {
    return;
  }

  // Special dynamic content handling
  PRUint32 naturalRole; // The natural role is the role that this type of element normally has
  aAccessible->GetRole(&naturalRole);
  if (role != naturalRole) {  // xhtml2:role is being used to override element's natural role
    FireDHTMLFocusRelatedEvents(aAccessible, role);
  }

  NS_IF_RELEASE(gLastFocusedNode);
  gLastFocusedNode = aNode;
  NS_IF_ADDREF(gLastFocusedNode);

  nsCOMPtr<nsPIAccessible> privateAccessible =
    do_QueryInterface(aAccessible);
  privateAccessible->FireToolkitEvent(nsIAccessibleEvent::EVENT_FOCUS,
                                      aAccessible, nsnull);
  if (mCaretAccessible)
    mCaretAccessible->AttachNewSelectionListener(aNode);
}

void nsRootAccessible::FireDHTMLMenuBarEvents(nsIAccessible *aAccessible, PRUint32 aEvent)
{
  // Will fire EVENT_MENUSTART or EVENT_MENUEND if we're in a menubar
  PRUint32 containerRole;
  while (aAccessible) {
    aAccessible->GetFinalRole(&containerRole);
    if (containerRole == ROLE_MENUBAR) {
      nsCOMPtr<nsPIAccessible> privateAccessible = do_QueryInterface(aAccessible);
      privateAccessible->FireToolkitEvent(aEvent, aAccessible, nsnull);
      return;
    }
    else if (containerRole != ROLE_MENUPOPUP) {
      break;
    }
    nsCOMPtr<nsIAccessible> nextParent;
    aAccessible->GetParent(getter_AddRefs(nextParent));
    aAccessible = nextParent;
  }
}


void nsRootAccessible::FireDHTMLFocusRelatedEvents(nsIAccessible *aAccessible, PRUint32 aRole)
{
  // Rule set 1: special menu events
  // Use focus events on DHTML menuitems to indicate when to fire menustart and 
  // menuend for menubars, as well as menupopupstart and menupopupend for popups

  // How menupopupstart/menupopupend events are computed for firing:
  // We keep track of the last popup the user was in mMenuAccessible.
  // Store null there if the last thing that was focused was not a menuitem.
  // If there's a menuitem focus it checks to see if you're still in that menu.
  // If the new menu != mMenuAccessible, then a menupopupstart is fired
  // Once something else besides a menuitem is focused, menupopupend is fired,.
  // the menustart/menuend events are for a menubar.

  // How menustart/menuend events (for menubars) are computed for firing:
  // Starting from mMenuAccessible, walk up from its chain of menupopup parents 
  // until we're  no longer in a menupopup. If that ancestor is a menubar, then fire
  // a menustart or menuend event, depending on whether we're now focusing a menuitem
  // or something else.

  nsCOMPtr<nsIAccessible> newMenuAccessible;
  PRUint32 newMenuRole;
  if (aRole == ROLE_MENUITEM) {
    aAccessible->GetParent(getter_AddRefs(newMenuAccessible));
    if (newMenuAccessible) {
      newMenuAccessible->GetFinalRole(&newMenuRole);
      if (newMenuRole != ROLE_MENUPOPUP && newMenuRole != ROLE_MENUBAR) {
        newMenuAccessible = nsnull;  // Menuitem not in a menu
      }
    }
  }
  if (newMenuAccessible != mMenuAccessible) {
    if (mMenuAccessible) {
      // We must synthesize a menupopupend event when a menu was focused and
      // apparently loses focus (something else gets focus)
      PRUint32 currentMenuRole;
      mMenuAccessible->GetFinalRole(&currentMenuRole);
      if (currentMenuRole == ROLE_MENUPOPUP) {
        nsCOMPtr<nsPIAccessible> privateAccessible = do_QueryInterface(mMenuAccessible);
        privateAccessible->FireToolkitEvent(nsIAccessibleEvent::EVENT_MENUPOPUPEND,
                                            mMenuAccessible, nsnull);
      }
      if (!newMenuAccessible) {  // No longer in a menu
        FireDHTMLMenuBarEvents(mMenuAccessible, nsIAccessibleEvent::EVENT_MENUEND);
      }
    }
    if (newMenuAccessible) {
      // We must synthesize a menupopupstart event for DHTML when a menu item gets focused
      // This could be a DHTML menu in which case there will be no DOMMenuActive event to help do this
      if (!mMenuAccessible) {  // Was not in menu
        FireDHTMLMenuBarEvents(newMenuAccessible, nsIAccessibleEvent::EVENT_MENUSTART);
      }
      if (newMenuRole == ROLE_MENUPOPUP) {
        nsCOMPtr<nsPIAccessible> privateAccessible = do_QueryInterface(newMenuAccessible);
        privateAccessible->FireToolkitEvent(nsIAccessibleEvent::EVENT_MENUPOPUPSTART,
                                            newMenuAccessible, nsnull);
      }
    }
    mMenuAccessible = newMenuAccessible;
  }

  // Rule set 2: selection events that mirror focus events
  // Mirror selection events to focus, but only for widgets that are selectable
  // but not a descendent of a multi-selectable widget
  PRUint32 state;
  aAccessible->GetFinalState(&state);
  PRBool isMultiSelectOn = PR_TRUE;
  if (state & STATE_SELECTABLE) {
    nsCOMPtr<nsIAccessible> container = aAccessible;
    PRUint32 containerRole;
    while (0 == (state & STATE_MULTISELECTABLE)) {
      nsIAccessible *current = container;
      current->GetParent(getter_AddRefs(container));      
      if (!container || (NS_SUCCEEDED(container->GetFinalRole(&containerRole)) &&
                         containerRole == ROLE_PANE)) {
        isMultiSelectOn = PR_FALSE;
        break;
      }
      container->GetFinalState(&state);
    }

    if (!isMultiSelectOn) {
      nsCOMPtr<nsPIAccessible> privateAccessible = do_QueryInterface(aAccessible);
      privateAccessible->FireToolkitEvent(nsIAccessibleEvent::EVENT_SELECTION,
                                          aAccessible, nsnull);
    }
  }
}

void nsRootAccessible::FireCurrentFocusEvent()
{
  nsCOMPtr<nsIDOMWindow> domWin;
  GetWindow(getter_AddRefs(domWin));
  nsCOMPtr<nsPIDOMWindow> privateDOMWindow(do_QueryInterface(domWin));
  if (!privateDOMWindow) {
    return;
  }
  nsIFocusController *focusController = privateDOMWindow->GetRootFocusController();
  if (!focusController) {
    return;
  }
  nsCOMPtr<nsIDOMElement> focusedElement;
  focusController->GetFocusedElement(getter_AddRefs(focusedElement));
  nsCOMPtr<nsIDOMNode> focusedNode(do_QueryInterface(focusedElement));
  if (!focusedNode) {
    // Document itself may have focus
    nsCOMPtr<nsIDOMWindowInternal> focusedWinInternal;
    focusController->GetFocusedWindow(getter_AddRefs(focusedWinInternal));
    if (focusedWinInternal) {
      nsCOMPtr<nsIDOMDocument> focusedDOMDocument;
      focusedWinInternal->GetDocument(getter_AddRefs(focusedDOMDocument));
      focusedNode = do_QueryInterface(focusedDOMDocument);
    }
    if (!focusedNode) {
      return;  // Could not get a focused document either
    }
  }

  // Simulate a focus event so that we can reuse code that fires focus for container children like treeitems
  nsIContent *rootContent = mDocument->GetRootContent();
  nsPresContext *presContext = GetPresContext();
  if (rootContent && presContext) {
    nsCOMPtr<nsIDOMEvent> event;
    nsCOMPtr<nsIEventListenerManager> manager;
    rootContent->GetListenerManager(getter_AddRefs(manager));
    if (manager && NS_SUCCEEDED(manager->CreateEvent(presContext, nsnull,
                                                     NS_LITERAL_STRING("Events"),
                                                     getter_AddRefs(event))) &&
        NS_SUCCEEDED(event->InitEvent(NS_LITERAL_STRING("focus"), PR_TRUE, PR_TRUE))) {
      HandleEvent(event);
    }
  }
}

// --------------- nsIDOMEventListener Methods (3) ------------------------

NS_IMETHODIMP nsRootAccessible::HandleEvent(nsIDOMEvent* aEvent)
{
  // Turn DOM events in accessibility events

  // Get info about event and target
  nsCOMPtr<nsIDOMNode> targetNode; 
  GetTargetNode(aEvent, getter_AddRefs(targetNode));
  if (!targetNode)
    return NS_ERROR_FAILURE;

  nsAutoString eventType;
  aEvent->GetType(eventType);
  nsAutoString localName;
  targetNode->GetLocalName(localName);
#ifdef DEBUG_aleventhal
  // Very useful for debugging, please leave this here.
  if (eventType.LowerCaseEqualsLiteral("dommenuitemactive")) {
    printf("\ndebugging dommenuitemactive events for %s", NS_ConvertUCS2toUTF8(localName).get());
  }
  if (localName.EqualsIgnoreCase("tree")) {
    printf("\ndebugging events in tree, event is %s", NS_ConvertUCS2toUTF8(eventType).get());
  }
#endif

  nsCOMPtr<nsIPresShell> eventShell = GetPresShellFor(targetNode);

#ifdef MOZ_ACCESSIBILITY_ATK
  nsCOMPtr<nsIDOMHTMLAnchorElement> anchorElement(do_QueryInterface(targetNode));
  if (anchorElement) {
    nsCOMPtr<nsIDOMNode> blockNode;
    // For ATK, we don't create any individual object for hyperlink, use its parent who has block frame instead
    if (NS_SUCCEEDED(nsAccessible::GetParentBlockNode(eventShell, targetNode, getter_AddRefs(blockNode))))
      targetNode = blockNode;
  }
#endif

  if (!eventShell) {
    return NS_OK;
  }
      
  if (eventType.LowerCaseEqualsLiteral("unload")) {
    // Only get cached accessible for unload -- so that we don't create it
    // just to destroy it.
    nsCOMPtr<nsIWeakReference> weakShell(do_GetWeakReference(eventShell));
    nsCOMPtr<nsIAccessibleDocument> accessibleDoc =
      nsAccessNode::GetDocAccessibleFor(weakShell);
    nsCOMPtr<nsPIAccessibleDocument> privateAccDoc = do_QueryInterface(accessibleDoc);
    if (privateAccDoc) {
      privateAccDoc->Destroy();
    }
    return NS_OK;
  }

  nsCOMPtr<nsIAccessible> accessible;
  if (NS_FAILED(mAccService->GetAccessibleInShell(targetNode, eventShell,
                                                  getter_AddRefs(accessible))))
    return NS_OK;
  
#ifdef MOZ_XUL
  // If it's a tree element, need the currently selected item
  nsCOMPtr<nsIAccessible> treeItemAccessible;
  if (localName.EqualsLiteral("tree")) {
    nsCOMPtr<nsIDOMXULMultiSelectControlElement> multiSelect =
      do_QueryInterface(targetNode);
    if (multiSelect) {
      PRInt32 treeIndex = -1;
      multiSelect->GetCurrentIndex(&treeIndex);
      if (treeIndex >= 0) {
        nsCOMPtr<nsIAccessibleTreeCache> treeCache(do_QueryInterface(accessible));
        if (!treeCache ||
            NS_FAILED(treeCache->GetCachedTreeitemAccessible(
                      treeIndex,
                      nsnull,
                      getter_AddRefs(treeItemAccessible))) ||
                      !treeItemAccessible) {
          return NS_ERROR_OUT_OF_MEMORY;
        }
        accessible = treeItemAccessible;
      }
    }
  }
#endif

  nsCOMPtr<nsPIAccessible> privAcc(do_QueryInterface(accessible));

#ifndef MOZ_ACCESSIBILITY_ATK
#ifdef MOZ_XUL
  // tree event
  if (treeItemAccessible) {
    if (eventType.LowerCaseEqualsLiteral("focus")) {
      FireAccessibleFocusEvent(accessible, targetNode); // Tree has focus
    }
    else if (eventType.LowerCaseEqualsLiteral("dommenuitemactive") || 
             eventType.LowerCaseEqualsLiteral("select")) {
      if (gLastFocusedNode == targetNode) {
        privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_FOCUS, 
                                  treeItemAccessible, nsnull);
      }
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_SELECTION, 
                               treeItemAccessible, nsnull);
    }
    return NS_OK;
  }
  else 
#endif
  if (eventType.LowerCaseEqualsLiteral("dommenuitemactive")) {
    nsCOMPtr<nsIAccessible> containerAccessible = accessible;
    PRUint32 containerState = 0;
    do {
      nsIAccessible *tempAccessible = containerAccessible;
      tempAccessible->GetParent(getter_AddRefs(containerAccessible));
      if (!containerAccessible) {
        break;
      }
      containerAccessible->GetFinalState(&containerState);
    }
    while ((containerState & STATE_HASPOPUP) == 0);

    // Only fire focus event for DOMMenuItemActive is not inside collapsed popup
    if (0 == (containerState & STATE_COLLAPSED)) {
      FireAccessibleFocusEvent(accessible, targetNode);
    }
  }
  else if (eventType.LowerCaseEqualsLiteral("focus")) {
    nsCOMPtr<nsIDOMXULSelectControlElement> selectControl =
      do_QueryInterface(targetNode);
    // Send focus to individual radio button or selected item
    if (selectControl) {
      nsCOMPtr<nsIDOMXULMenuListElement> menuList =
        do_QueryInterface(targetNode);
      if (!menuList) {
        // Don't do this for menu lists, the items only get focused
        // when the list is open, based on DOMMenuitemActive events
        nsCOMPtr<nsIDOMXULSelectControlItemElement> selectedItem;
        selectControl->GetSelectedItem(getter_AddRefs(selectedItem));
        if (selectedItem) {
          targetNode = do_QueryInterface(selectedItem);
        }

        if (!targetNode ||
            NS_FAILED(mAccService->GetAccessibleInShell(targetNode, eventShell,
                      getter_AddRefs(accessible)))) {
          return NS_OK;
        }
      }
    }
    FireAccessibleFocusEvent(accessible, targetNode);
  }
  else if (eventType.LowerCaseEqualsLiteral("valuechange")) { 
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_VALUE_CHANGE, 
                              accessible, nsnull);
  }
  else if (eventType.EqualsLiteral("AlertActive")) { 
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_ALERT, 
                              accessible, nsnull);
  }
  else if (eventType.LowerCaseEqualsLiteral("checkboxstatechange") ||
           eventType.LowerCaseEqualsLiteral("openstatechange")) {
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, 
                                accessible, nsnull);
    }
  else if (eventType.LowerCaseEqualsLiteral("radiostatechange") ) {
    // first the XUL radio buttons
    if (targetNode &&
        NS_SUCCEEDED(mAccService->GetAccessibleInShell(targetNode, eventShell,
                                                       getter_AddRefs(accessible)))) {
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, 
                                accessible, nsnull);
      FireAccessibleFocusEvent(accessible, targetNode);
    }
    else { // for the html radio buttons -- apparently the focus code just works. :-)
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, 
                                accessible, nsnull);
    }
  }
  else if (eventType.LowerCaseEqualsLiteral("dommenubaractive")) 
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_MENUSTART, accessible, nsnull);
  else if (eventType.LowerCaseEqualsLiteral("dommenubarinactive")) {
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_MENUEND, accessible, nsnull);
    FireCurrentFocusEvent();
  }
  else if (eventType.LowerCaseEqualsLiteral("popuphiding")) {
    // If accessible focus was inside popup that closes,
    // then restore it to true current focus.
    // This is the case when we've been getting DOMMenuItemActive events
    // inside of a combo box that closes. The real focus is on the combo box.
    if (!gLastFocusedNode) {
      return NS_OK;
    }
    nsCOMPtr<nsIDOMNode> parentOfFocus;
    gLastFocusedNode->GetParentNode(getter_AddRefs(parentOfFocus));
    if (parentOfFocus != targetNode) {
      return NS_OK;
    }
    // Focus was inside of popup that's being hidden
    FireCurrentFocusEvent();
  }
  else {
    // Menu popup events
    PRUint32 menuEvent = 0;
    if (eventType.LowerCaseEqualsLiteral("popupshown")) {
      menuEvent = nsIAccessibleEvent::EVENT_MENUPOPUPSTART;
    }
    else if (eventType.EqualsLiteral("DOMMenuInactive")) {
      menuEvent = nsIAccessibleEvent::EVENT_MENUPOPUPEND;
    }
    if (menuEvent) {
      PRUint32 role = ROLE_NOTHING;
      accessible->GetRole(&role);
      if (role == ROLE_MENUPOPUP)
        privAcc->FireToolkitEvent(menuEvent, accessible, nsnull);
    }
  }
#else
  AtkStateChange stateData;
  if (eventType.EqualsIgnoreCase("load")) {
    nsCOMPtr<nsIHTMLDocument> htmlDoc(do_QueryInterface(targetNode));
    if (htmlDoc) {
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_REORDER, 
                                accessible, nsnull);
    }
  }
  else if (eventType.LowerCaseEqualsLiteral("focus") || 
      eventType.LowerCaseEqualsLiteral("dommenuitemactive")) {
    if (treeItemAccessible) { // use focused treeitem
      privAcc = do_QueryInterface(treeItemAccessible);
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_FOCUS, 
                                treeItemAccessible, nsnull);
    }
    else if (anchorElement) {
      nsCOMPtr<nsIAccessibleHyperText> hyperText(do_QueryInterface(accessible));
      if (hyperText) {
        PRInt32 selectedLink;
        hyperText->GetSelectedLinkIndex(&selectedLink);
        privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_ATK_LINK_SELECTED, accessible, &selectedLink);
      }
    }
    else
      FireAccessibleFocusEvent(accessible, targetNode);
  }
  else if (eventType.LowerCaseEqualsLiteral("select")) {
    if (treeItemAccessible) { // it's a XUL <tree>
      // use EVENT_FOCUS instead of EVENT_ATK_SELECTION_CHANGE
      privAcc = do_QueryInterface(treeItemAccessible);
      privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_FOCUS, 
                                treeItemAccessible, nsnull);
    }
  }
#if 0
  // XXX todo: value change events for ATK are done with 
  // AtkPropertyChange, PROP_VALUE. Need the old and new value.
  // Not sure how we'll get the old value.
  // Aaron: I think this is a problem with the ATK API -- it's much harder to
  // grab the old value for all the application developers than it is for
  // AT's to cache old values when they need to (when would that be!?)
  else if (eventType.LowerCaseEqualsLiteral("valuechange")) { 
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_VALUE_CHANGE, 
                              accessible, nsnull);
  }
#endif
  else if (eventType.LowerCaseEqualsLiteral("checkboxstatechange") || // it's a XUL <checkbox>
           eventType.LowerCaseEqualsLiteral("radiostatechange")) { // it's a XUL <radio>
    accessible->GetFinalState(&stateData.state);
    stateData.enable = (stateData.state & STATE_CHECKED) != 0;
    stateData.state = STATE_CHECKED;
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, accessible, &stateData);
    if (eventType.LowerCaseEqualsLiteral("radiostatechange")) {
      FireAccessibleFocusEvent(accessible, targetNode);
    }
  }
  else if (eventType.LowerCaseEqualsLiteral("openstatechange")) { // collapsed/expanded changed
    accessible->GetFinalState(&stateData.state);
    stateData.enable = (stateData.state & STATE_EXPANDED) != 0;
    stateData.state = STATE_EXPANDED;
    privAcc->FireToolkitEvent(nsIAccessibleEvent::EVENT_STATE_CHANGE, accessible, &stateData);
  }
  else if (eventType.LowerCaseEqualsLiteral("popuphiding")) {
    // If accessible focus was inside popup that closes,
    // then restore it to true current focus.
    // This is the case when we've been getting DOMMenuItemActive events
    // inside of a combo box that closes. The real focus is on the combo box.
    if (!gLastFocusedNode) {
      return NS_OK;
    }
    nsCOMPtr<nsIDOMNode> parentOfFocus;
    gLastFocusedNode->GetParentNode(getter_AddRefs(parentOfFocus));
    if (parentOfFocus != targetNode) {
      return NS_OK;
    }
    // Focus was inside of popup that's being hidden
    FireCurrentFocusEvent();
  }
  else if (eventType.LowerCaseEqualsLiteral("popupshown")) {
    FireAccessibleFocusEvent(accessible, targetNode);
  }
  else if (eventType.EqualsLiteral("DOMMenuInactive")) {
    //FireAccessibleFocusEvent(accessible, targetNode);  // Not yet used in ATK
  }
#endif
  return NS_OK;
}

void nsRootAccessible::GetTargetNode(nsIDOMEvent *aEvent, nsIDOMNode **aTargetNode)
{
  *aTargetNode = nsnull;

  nsCOMPtr<nsIDOMNSEvent> nsevent(do_QueryInterface(aEvent));

  if (nsevent) {
    nsCOMPtr<nsIDOMEventTarget> domEventTarget;
    nsevent->GetOriginalTarget(getter_AddRefs(domEventTarget));
    nsCOMPtr<nsIContent> content(do_QueryInterface(domEventTarget));
    nsIContent *bindingParent;
    if (content && content->IsContentOfType(nsIContent::eHTML) &&
      (bindingParent = content->GetBindingParent()) != nsnull) {
      // Use binding parent when the event occurs in 
      // anonymous HTML content.
      // This gets the following important cases correct:
      // 1. Inserted <dialog> buttons like OK, Cancel, Help.
      // 2. XUL menulists and comboboxes.
      // 3. The focused radio button in a group.
      CallQueryInterface(bindingParent, aTargetNode);
      NS_ASSERTION(*aTargetNode, "No target node for binding parent of anonymous event target");
      return;
    }
    if (domEventTarget) {
      CallQueryInterface(domEventTarget, aTargetNode);
    }
  }
}

void nsRootAccessible::FireFocusCallback(nsITimer *aTimer, void *aClosure)
{
  nsRootAccessible *rootAccessible = NS_STATIC_CAST(nsRootAccessible*, aClosure);
  NS_ASSERTION(rootAccessible, "How did we get here without a root accessible?");
  rootAccessible->FireCurrentFocusEvent();
}

// ------- nsIDOMFocusListener Methods (1) -------------

NS_IMETHODIMP nsRootAccessible::Focus(nsIDOMEvent* aEvent) 
{ 
  return HandleEvent(aEvent);
}

NS_IMETHODIMP nsRootAccessible::Blur(nsIDOMEvent* aEvent) 
{ 
  return NS_OK; 
}

// ------- nsIDOMFormListener Methods (5) -------------

NS_IMETHODIMP nsRootAccessible::Submit(nsIDOMEvent* aEvent) 
{ 
  return NS_OK; 
}

NS_IMETHODIMP nsRootAccessible::Reset(nsIDOMEvent* aEvent) 
{ 
  return NS_OK; 
}

NS_IMETHODIMP nsRootAccessible::Change(nsIDOMEvent* aEvent)
{
  // get change events when the form elements changes its state, checked->not,
  // deleted text, new text, change in selection for list/combo boxes
  // this may be the event that we have the individual Accessible objects
  // handle themselves -- have list/combos figure out the change in selection
  // have textareas and inputs fire a change of state etc...
  return NS_OK;   // Ignore form change events in MSAA
}

// gets Select events when text is selected in a textarea or input
NS_IMETHODIMP nsRootAccessible::Select(nsIDOMEvent* aEvent) 
{
  return HandleEvent(aEvent);
}

// gets Input events when text is entered or deleted in a textarea or input
NS_IMETHODIMP nsRootAccessible::Input(nsIDOMEvent* aEvent) 
{ 
  return NS_OK; 
}

// ------- nsIDOMXULListener Methods (8) ---------------

NS_IMETHODIMP nsRootAccessible::PopupShowing(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::PopupShown(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::PopupHiding(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::PopupHidden(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::Close(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::Command(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::Broadcast(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::CommandUpdate(nsIDOMEvent* aEvent) { return NS_OK; }

NS_IMETHODIMP nsRootAccessible::Shutdown()
{
  // Called manually or by nsAccessNode::~nsAccessNode()
  if (!mWeakShell) {
    return NS_OK;  // Already shutdown
  }
  mMenuAccessible = nsnull;
  mCaretAccessible = nsnull;
  mAccService = nsnull;
  if (mFireEventTimer) {
    mFireFocusTimer->Cancel();
    mFireFocusTimer = nsnull;
  }

  return nsDocAccessibleWrap::Shutdown();
}