/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=2 et :
 * 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/. */

/*
 * Base class for all element classes; this provides an implementation
 * of DOM Core's nsIDOMElement, implements nsIContent, provides
 * utility methods for subclasses, and so forth.
 */

#ifndef mozilla_dom_Element_h__
#define mozilla_dom_Element_h__

#include "mozilla/dom/FragmentOrElement.h" // for base class
#include "nsChangeHint.h"                  // for enum
#include "nsEventStates.h"                 // for member
#include "mozilla/dom/DirectionalityUtils.h"
#include "nsCOMPtr.h"
#include "nsAutoPtr.h"
#include "nsIDOMElement.h"
#include "nsIDOMDocumentFragment.h"
#include "nsILinkHandler.h"
#include "nsNodeUtils.h"
#include "nsAttrAndChildArray.h"
#include "mozFlushType.h"
#include "nsDOMAttributeMap.h"
#include "nsIWeakReference.h"
#include "nsCycleCollectionParticipant.h"
#include "nsIDocument.h"
#include "nsIDOMNodeSelector.h"
#include "nsIDOMXPathNSResolver.h"
#include "nsPresContext.h"
#include "nsDOMClassInfoID.h" // DOMCI_DATA
#include "nsIDOMTouchEvent.h"
#include "nsIInlineEventHandlers.h"
#include "mozilla/CORSMode.h"
#include "mozilla/Attributes.h"
#include "nsContentUtils.h"
#include "nsINodeList.h"
#include "mozilla/ErrorResult.h"
#include "nsIScrollableFrame.h"
#include "nsIDOMAttr.h"
#include "nsISMILAttr.h"
#include "nsClientRect.h"
#include "nsIDOMDOMTokenList.h"

class nsIDOMEventListener;
class nsIFrame;
class nsIDOMNamedNodeMap;
class nsIDOMCSSStyleDeclaration;
class nsIURI;
class nsINodeInfo;
class nsIControllers;
class nsEventChainVisitor;
class nsEventListenerManager;
class nsIScrollableFrame;
class nsAttrValueOrString;
class ContentUnbinder;
class nsClientRect;
class nsClientRectList;
class nsIHTMLCollection;
class nsContentList;
class nsDOMTokenList;
struct nsRect;
class nsEventStateManager;
class nsFocusManager;
class nsGlobalWindow;
class nsICSSDeclaration;
class nsISMILAttr;

already_AddRefed<nsContentList>
NS_GetContentList(nsINode* aRootNode,
                  int32_t  aMatchNameSpaceId,
                  const nsAString& aTagname);

#define ELEMENT_FLAG_BIT(n_) NODE_FLAG_BIT(NODE_TYPE_SPECIFIC_BITS_OFFSET + (n_))

// Element-specific flags
enum {
  // Set if the element has a pending style change.
  ELEMENT_HAS_PENDING_RESTYLE =                 ELEMENT_FLAG_BIT(0),

  // Set if the element is a potential restyle root (that is, has a style
  // change pending _and_ that style change will attempt to restyle
  // descendants).
  ELEMENT_IS_POTENTIAL_RESTYLE_ROOT =           ELEMENT_FLAG_BIT(1),

  // Set if the element has a pending animation style change.
  ELEMENT_HAS_PENDING_ANIMATION_RESTYLE =       ELEMENT_FLAG_BIT(2),

  // Set if the element is a potential animation restyle root (that is,
  // has an animation style change pending _and_ that style change
  // will attempt to restyle descendants).
  ELEMENT_IS_POTENTIAL_ANIMATION_RESTYLE_ROOT = ELEMENT_FLAG_BIT(3),

  // All of those bits together, for convenience.
  ELEMENT_ALL_RESTYLE_FLAGS = ELEMENT_HAS_PENDING_RESTYLE |
                              ELEMENT_IS_POTENTIAL_RESTYLE_ROOT |
                              ELEMENT_HAS_PENDING_ANIMATION_RESTYLE |
                              ELEMENT_IS_POTENTIAL_ANIMATION_RESTYLE_ROOT,

  // Just the HAS_PENDING bits, for convenience
  ELEMENT_PENDING_RESTYLE_FLAGS = ELEMENT_HAS_PENDING_RESTYLE |
                                  ELEMENT_HAS_PENDING_ANIMATION_RESTYLE,

  // Remaining bits are for subclasses
  ELEMENT_TYPE_SPECIFIC_BITS_OFFSET = NODE_TYPE_SPECIFIC_BITS_OFFSET + 4
};

#undef ELEMENT_FLAG_BIT

namespace mozilla {
namespace dom {

class Link;

// IID for the dom::Element interface
#define NS_ELEMENT_IID \
{ 0xc6c049a1, 0x96e8, 0x4580, \
  { 0xa6, 0x93, 0xb9, 0x5f, 0x53, 0xbe, 0xe8, 0x1c } }

class Element : public FragmentOrElement
{
public:
#ifdef MOZILLA_INTERNAL_API
  Element(already_AddRefed<nsINodeInfo> aNodeInfo) :
    FragmentOrElement(aNodeInfo),
    mState(NS_EVENT_STATE_MOZ_READONLY)
  {
    NS_ABORT_IF_FALSE(mNodeInfo->NodeType() == nsIDOMNode::ELEMENT_NODE,
                      "Bad NodeType in aNodeInfo");
    SetIsElement();
  }
#endif // MOZILLA_INTERNAL_API

  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ELEMENT_IID)

  /**
   * Method to get the full state of this element.  See nsEventStates.h for
   * the possible bits that could be set here.
   */
  nsEventStates State() const {
    // mState is maintained by having whoever might have changed it
    // call UpdateState() or one of the other mState mutators.
    return mState;
  }

  /**
   * Ask this element to update its state.  If aNotify is false, then
   * state change notifications will not be dispatched; in that
   * situation it is the caller's responsibility to dispatch them.
   *
   * In general, aNotify should only be false if we're guaranteed that
   * the element can't have a frame no matter what its style is
   * (e.g. if we're in the middle of adding it to the document or
   * removing it from the document).
   */
  void UpdateState(bool aNotify);
  
  /**
   * Method to update mState with link state information.  This does not notify.
   */
  void UpdateLinkState(nsEventStates aState);

  /**
   * Returns true if this element is either a full-screen element or an
   * ancestor of the full-screen element.
   */
  bool IsFullScreenAncestor() const {
    return mState.HasAtLeastOneOfStates(NS_EVENT_STATE_FULL_SCREEN_ANCESTOR |
                                        NS_EVENT_STATE_FULL_SCREEN);
  }

  /**
   * The style state of this element. This is the real state of the element
   * with any style locks applied for pseudo-class inspecting.
   */
  nsEventStates StyleState() const {
    if (!HasLockedStyleStates()) {
      return mState;
    }
    return StyleStateFromLocks();
  }

  /**
   * The style state locks applied to this element.
   */
  nsEventStates LockedStyleStates() const;

  /**
   * Add a style state lock on this element.
   */
  void LockStyleStates(nsEventStates aStates);

  /**
   * Remove a style state lock on this element.
   */
  void UnlockStyleStates(nsEventStates aStates);

  /**
   * Clear all style state locks on this element.
   */
  void ClearStyleStateLocks();

  /**
   * Get the inline style rule, if any, for this element.
   */
  virtual css::StyleRule* GetInlineStyleRule();

  /**
   * Set the inline style rule for this element. This will send an appropriate
   * AttributeChanged notification if aNotify is true.
   */
  virtual nsresult SetInlineStyleRule(css::StyleRule* aStyleRule,
                                      const nsAString* aSerialized,
                                      bool aNotify);

  /**
   * Get the SMIL override style rule for this element. If the rule hasn't been
   * created, this method simply returns null.
   */
  virtual css::StyleRule* GetSMILOverrideStyleRule();

  /**
   * Set the SMIL override style rule for this element. If aNotify is true, this
   * method will notify the document's pres context, so that the style changes
   * will be noticed.
   */
  virtual nsresult SetSMILOverrideStyleRule(css::StyleRule* aStyleRule,
                                            bool aNotify);

  /**
   * Returns a new nsISMILAttr that allows the caller to animate the given
   * attribute on this element.
   *
   * The CALLER OWNS the result and is responsible for deleting it.
   */
  virtual nsISMILAttr* GetAnimatedAttr(int32_t aNamespaceID, nsIAtom* aName)
  {
    return nullptr;
  }

  /**
   * Get the SMIL override style for this element. This is a style declaration
   * that is applied *after* the inline style, and it can be used e.g. to store
   * animated style values.
   *
   * Note: This method is analogous to the 'GetStyle' method in
   * nsGenericHTMLElement and nsStyledElement.
   */
  virtual nsICSSDeclaration* GetSMILOverrideStyle();

  /**
   * Returns if the element is labelable as per HTML specification.
   */
  virtual bool IsLabelable() const;

  /**
   * Is the attribute named stored in the mapped attributes?
   *
   * // XXXbz we use this method in HasAttributeDependentStyle, so svg
   *    returns true here even though it stores nothing in the mapped
   *    attributes.
   */
  NS_IMETHOD_(bool) IsAttributeMapped(const nsIAtom* aAttribute) const;

  /**
   * Get a hint that tells the style system what to do when
   * an attribute on this node changes, if something needs to happen
   * in response to the change *other* than the result of what is
   * mapped into style data via any type of style rule.
   */
  virtual nsChangeHint GetAttributeChangeHint(const nsIAtom* aAttribute,
                                              int32_t aModType) const;

  /**
   * Returns an atom holding the name of the "class" attribute on this
   * content node (if applicable).  Returns null if there is no
   * "class" attribute for this type of content node.
   */
  virtual nsIAtom *GetClassAttributeName() const;

  inline Directionality GetDirectionality() const {
    if (HasFlag(NODE_HAS_DIRECTION_RTL)) {
      return eDir_RTL;
    }

    if (HasFlag(NODE_HAS_DIRECTION_LTR)) {
      return eDir_LTR;
    }

    return eDir_NotSet;
  }

  inline void SetDirectionality(Directionality aDir, bool aNotify) {
    UnsetFlags(NODE_ALL_DIRECTION_FLAGS);
    if (!aNotify) {
      RemoveStatesSilently(DIRECTION_STATES);
    }

    switch (aDir) {
      case (eDir_RTL):
        SetFlags(NODE_HAS_DIRECTION_RTL);
        if (!aNotify) {
          AddStatesSilently(NS_EVENT_STATE_RTL);
        }
        break;

      case(eDir_LTR):
        SetFlags(NODE_HAS_DIRECTION_LTR);
        if (!aNotify) {
          AddStatesSilently(NS_EVENT_STATE_LTR);
        }
        break;

      default:
        break;
    }

    /* 
     * Only call UpdateState if we need to notify, because we call
     * SetDirectionality for every element, and UpdateState is very very slow
     * for some elements.
     */
    if (aNotify) {
      UpdateState(true);
    }
  }

  bool GetBindingURL(nsIDocument *aDocument, css::URLValue **aResult);

  // The bdi element defaults to dir=auto if it has no dir attribute set.
  // Other elements will only have dir=auto if they have an explicit dir=auto,
  // which will mean that HasValidDir() returns true but HasFixedDir() returns
  // false
  inline bool HasDirAuto() const {
    return (!HasFixedDir() &&
            (HasValidDir() || NodeInfo()->Equals(nsGkAtoms::bdi)));
  }

protected:
  /**
   * Method to get the _intrinsic_ content state of this element.  This is the
   * state that is independent of the element's presentation.  To get the full
   * content state, use State().  See nsEventStates.h for
   * the possible bits that could be set here.
   */
  virtual nsEventStates IntrinsicState() const;

  /**
   * Method to add state bits.  This should be called from subclass
   * constructors to set up our event state correctly at construction
   * time and other places where we don't want to notify a state
   * change.
   */
  void AddStatesSilently(nsEventStates aStates) {
    mState |= aStates;
  }

  /**
   * Method to remove state bits.  This should be called from subclass
   * constructors to set up our event state correctly at construction
   * time and other places where we don't want to notify a state
   * change.
   */
  void RemoveStatesSilently(nsEventStates aStates) {
    mState &= ~aStates;
  }

private:
  // Need to allow the ESM, nsGlobalWindow, and the focus manager to
  // set our state
  friend class ::nsEventStateManager;
  friend class ::nsGlobalWindow;
  friend class ::nsFocusManager;

  // Also need to allow Link to call UpdateLinkState.
  friend class Link;

  void NotifyStateChange(nsEventStates aStates);

  void NotifyStyleStateChange(nsEventStates aStates);

  // Style state computed from element's state and style locks.
  nsEventStates StyleStateFromLocks() const;

  // Methods for the ESM to manage state bits.  These will handle
  // setting up script blockers when they notify, so no need to do it
  // in the callers unless desired.
  void AddStates(nsEventStates aStates) {
    NS_PRECONDITION(!aStates.HasAtLeastOneOfStates(INTRINSIC_STATES),
                    "Should only be adding ESM-managed states here");
    AddStatesSilently(aStates);
    NotifyStateChange(aStates);
  }
  void RemoveStates(nsEventStates aStates) {
    NS_PRECONDITION(!aStates.HasAtLeastOneOfStates(INTRINSIC_STATES),
                    "Should only be removing ESM-managed states here");
    RemoveStatesSilently(aStates);
    NotifyStateChange(aStates);
  }
public:
  virtual void UpdateEditableState(bool aNotify);

  virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
                              nsIContent* aBindingParent,
                              bool aCompileEventHandlers);
  virtual void UnbindFromTree(bool aDeep = true,
                              bool aNullParent = true);
  virtual already_AddRefed<nsINodeInfo> GetExistingAttrNameFromQName(const nsAString& aStr) const;
  nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                   const nsAString& aValue, bool aNotify)
  {
    return SetAttr(aNameSpaceID, aName, nullptr, aValue, aNotify);
  }

  NS_IMETHOD GetAttributes(nsIDOMNamedNodeMap** aAttributes);

  /**
   * Helper for SetAttr/SetParsedAttr. This method will return true if aNotify
   * is true or there are mutation listeners that must be triggered, the
   * attribute is currently set, and the new value that is about to be set is
   * different to the current value. As a perf optimization the new and old
   * values will not actually be compared if we aren't notifying and we don't
   * have mutation listeners (in which case it's cheap to just return false
   * and let the caller go ahead and set the value).
   * @param aOldValue Set to the old value of the attribute, but only if there
   *   are event listeners. If set, the type of aOldValue will be either
   *   nsAttrValue::eString or nsAttrValue::eAtom.
   * @param aModType Set to nsIDOMMutationEvent::MODIFICATION or to
   *   nsIDOMMutationEvent::ADDITION, but only if this helper returns true
   * @param aHasListeners Set to true if there are mutation event listeners
   *   listening for NS_EVENT_BITS_MUTATION_ATTRMODIFIED
   */
  bool MaybeCheckSameAttrVal(int32_t aNamespaceID, nsIAtom* aName,
                             nsIAtom* aPrefix,
                             const nsAttrValueOrString& aValue,
                             bool aNotify, nsAttrValue& aOldValue,
                             uint8_t* aModType, bool* aHasListeners);

  bool OnlyNotifySameValueSet(int32_t aNamespaceID, nsIAtom* aName,
                              nsIAtom* aPrefix,
                              const nsAttrValueOrString& aValue,
                              bool aNotify, nsAttrValue& aOldValue,
                              uint8_t* aModType, bool* aHasListeners)
  {
    if (MaybeCheckSameAttrVal(aNamespaceID, aName, aPrefix, aValue, aNotify,
                              aOldValue, aModType, aHasListeners)) {
      nsAutoScriptBlocker scriptBlocker;
      nsNodeUtils::AttributeSetToCurrentValue(this, aNamespaceID, aName);
      return true;
    }
    return false;
  }

  virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName, nsIAtom* aPrefix,
                           const nsAString& aValue, bool aNotify);
  virtual nsresult SetParsedAttr(int32_t aNameSpaceID, nsIAtom* aName,
                                 nsIAtom* aPrefix, nsAttrValue& aParsedValue,
                                 bool aNotify);
  virtual bool GetAttr(int32_t aNameSpaceID, nsIAtom* aName,
                         nsAString& aResult) const;
  virtual bool HasAttr(int32_t aNameSpaceID, nsIAtom* aName) const;
  // aCaseSensitive == eIgnoreCaase means ASCII case-insensitive matching.
  virtual bool AttrValueIs(int32_t aNameSpaceID, nsIAtom* aName,
                             const nsAString& aValue,
                             nsCaseTreatment aCaseSensitive) const;
  virtual bool AttrValueIs(int32_t aNameSpaceID, nsIAtom* aName,
                             nsIAtom* aValue,
                             nsCaseTreatment aCaseSensitive) const;
  virtual int32_t FindAttrValueIn(int32_t aNameSpaceID,
                                  nsIAtom* aName,
                                  AttrValuesArray* aValues,
                                  nsCaseTreatment aCaseSensitive) const;
  virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttribute,
                             bool aNotify);
  virtual const nsAttrName* GetAttrNameAt(uint32_t aIndex) const;
  virtual uint32_t GetAttrCount() const;
  virtual bool IsNodeOfType(uint32_t aFlags) const;

#ifdef DEBUG
  virtual void List(FILE* out = stdout, int32_t aIndent = 0) const
  {
    List(out, aIndent, EmptyCString());
  }
  virtual void DumpContent(FILE* out, int32_t aIndent, bool aDumpAll) const;
  void List(FILE* out, int32_t aIndent, const nsCString& aPrefix) const;
  void ListAttributes(FILE* out) const;
#endif

  /*
   * Attribute Mapping Helpers
   */
  struct MappedAttributeEntry {
    nsIAtom** attribute;
  };

  /**
   * A common method where you can just pass in a list of maps to check
   * for attribute dependence. Most implementations of
   * IsAttributeMapped should use this function as a default
   * handler.
   */
  template<size_t N>
  static bool
  FindAttributeDependence(const nsIAtom* aAttribute,
                          const MappedAttributeEntry* const (&aMaps)[N])
  {
    return FindAttributeDependence(aAttribute, aMaps, N);
  }

private:
  static bool
  FindAttributeDependence(const nsIAtom* aAttribute,
                          const MappedAttributeEntry* const aMaps[],
                          uint32_t aMapCount);

public:
  void GetTagName(nsAString& aTagName) const
  {
    aTagName = NodeName();
  }
  void GetId(nsAString& aId) const
  {
    GetAttr(kNameSpaceID_None, nsGkAtoms::id, aId);
  }
  void SetId(const nsAString& aId)
  {
    SetAttr(kNameSpaceID_None, nsGkAtoms::id, aId, true);
  }

  nsDOMTokenList* GetClassList();
  nsDOMAttributeMap* GetAttributes()
  {
    nsDOMSlots *slots = DOMSlots();
    if (!slots->mAttributeMap) {
      slots->mAttributeMap = new nsDOMAttributeMap(this);
    }

    return slots->mAttributeMap;
  }
  virtual void GetAttribute(const nsAString& aName, nsString& aReturn);
  void GetAttributeNS(const nsAString& aNamespaceURI,
                      const nsAString& aLocalName,
                      nsAString& aReturn);
  void SetAttribute(const nsAString& aName, const nsAString& aValue,
                    ErrorResult& aError);
  void SetAttributeNS(const nsAString& aNamespaceURI,
                      const nsAString& aLocalName,
                      const nsAString& aValue,
                      ErrorResult& aError);
  virtual void RemoveAttribute(const nsAString& aName,
                               ErrorResult& aError);
  void RemoveAttributeNS(const nsAString& aNamespaceURI,
                         const nsAString& aLocalName,
                         ErrorResult& aError);
  virtual bool HasAttribute(const nsAString& aName) const
  {
    return InternalGetExistingAttrNameFromQName(aName) != nullptr;
  }
  bool HasAttributeNS(const nsAString& aNamespaceURI,
                      const nsAString& aLocalName) const;
  already_AddRefed<nsIHTMLCollection>
    GetElementsByTagName(const nsAString& aQualifiedName);
  already_AddRefed<nsIHTMLCollection>
    GetElementsByTagNameNS(const nsAString& aNamespaceURI,
                           const nsAString& aLocalName,
                           ErrorResult& aError);
  already_AddRefed<nsIHTMLCollection>
    GetElementsByClassName(const nsAString& aClassNames);
  Element* GetFirstElementChild() const;
  Element* GetLastElementChild() const;
  Element* GetPreviousElementSibling() const
  {
    nsIContent* previousSibling = GetPreviousSibling();
    while (previousSibling) {
      if (previousSibling->IsElement()) {
        return previousSibling->AsElement();
      }
      previousSibling = previousSibling->GetPreviousSibling();
    }

    return nullptr;
  }
  Element* GetNextElementSibling() const
  {
    nsIContent* nextSibling = GetNextSibling();
    while (nextSibling) {
      if (nextSibling->IsElement()) {
        return nextSibling->AsElement();
      }
      nextSibling = nextSibling->GetNextSibling();
    }

    return nullptr;
  }
  uint32_t ChildElementCount()
  {
    return Children()->Length();
  }
  bool MozMatchesSelector(const nsAString& aSelector,
                          ErrorResult& aError);
  void SetCapture(bool aRetargetToElement)
  {
    // If there is already an active capture, ignore this request. This would
    // occur if a splitter, frame resizer, etc had already captured and we don't
    // want to override those.
    if (!nsIPresShell::GetCapturingContent()) {
      nsIPresShell::SetCapturingContent(this, CAPTURE_PREVENTDRAG |
        (aRetargetToElement ? CAPTURE_RETARGETTOELEMENT : 0));
    }
  }
  void ReleaseCapture()
  {
    if (nsIPresShell::GetCapturingContent() == this) {
      nsIPresShell::SetCapturingContent(nullptr, 0);
    }
  }
  void MozRequestFullScreen();
  void MozRequestPointerLock()
  {
    OwnerDoc()->RequestPointerLock(this);
  }
  nsIDOMAttr* GetAttributeNode(const nsAString& aName);
  already_AddRefed<nsIDOMAttr> SetAttributeNode(nsIDOMAttr* aNewAttr,
                                                ErrorResult& aError);
  already_AddRefed<nsIDOMAttr> RemoveAttributeNode(nsIDOMAttr* aOldAttr,
                                                   ErrorResult& aError);
  nsIDOMAttr* GetAttributeNodeNS(const nsAString& aNamespaceURI,
                                 const nsAString& aLocalName,
                                 ErrorResult& aError);
  already_AddRefed<nsIDOMAttr> SetAttributeNodeNS(nsIDOMAttr* aNewAttr,
                                                  ErrorResult& aError);

  already_AddRefed<nsClientRectList> GetClientRects(ErrorResult& aError);
  already_AddRefed<nsClientRect> GetBoundingClientRect();
  void ScrollIntoView(bool aTop);
  int32_t ScrollTop()
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    return sf ? sf->GetScrollPositionCSSPixels().y : 0;
  }
  void SetScrollTop(int32_t aScrollTop)
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    if (sf) {
      sf->ScrollToCSSPixels(nsIntPoint(sf->GetScrollPositionCSSPixels().x,
                                       aScrollTop));
    }
  }
  int32_t ScrollLeft()
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    return sf ? sf->GetScrollPositionCSSPixels().x : 0;
  }
  void SetScrollLeft(int32_t aScrollLeft)
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    if (sf) {
      sf->ScrollToCSSPixels(nsIntPoint(aScrollLeft,
                                       sf->GetScrollPositionCSSPixels().y));
    }
  }
  int32_t ScrollWidth();
  int32_t ScrollHeight();
  int32_t ClientTop()
  {
    return nsPresContext::AppUnitsToIntCSSPixels(GetClientAreaRect().y);
  }
  int32_t ClientLeft()
  {
    return nsPresContext::AppUnitsToIntCSSPixels(GetClientAreaRect().x);
  }
  int32_t ClientWidth()
  {
    return nsPresContext::AppUnitsToIntCSSPixels(GetClientAreaRect().width);
  }
  int32_t ClientHeight()
  {
    return nsPresContext::AppUnitsToIntCSSPixels(GetClientAreaRect().height);
  }
  int32_t ScrollTopMax()
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    return sf ?
           nsPresContext::AppUnitsToIntCSSPixels(sf->GetScrollRange().YMost()) :
           0;
  }
  int32_t ScrollLeftMax()
  {
    nsIScrollableFrame* sf = GetScrollFrame();
    return sf ?
           nsPresContext::AppUnitsToIntCSSPixels(sf->GetScrollRange().XMost()) :
           0;
  }

  //----------------------------------------

  /**
   * Add a script event listener with the given event handler name
   * (like onclick) and with the value as JS
   * @param aEventName the event listener name
   * @param aValue the JS to attach
   * @param aDefer indicates if deferred execution is allowed
   */
  nsresult SetEventHandler(nsIAtom* aEventName,
                           const nsAString& aValue,
                           bool aDefer = true);

  /**
   * Do whatever needs to be done when the mouse leaves a link
   */
  nsresult LeaveLink(nsPresContext* aPresContext);

  static bool ShouldBlur(nsIContent *aContent);

  /**
   * Method to create and dispatch a left-click event loosely based on
   * aSourceEvent. If aFullDispatch is true, the event will be dispatched
   * through the full dispatching of the presshell of the aPresContext; if it's
   * false the event will be dispatched only as a DOM event.
   * If aPresContext is nullptr, this does nothing.
   */
  static nsresult DispatchClickEvent(nsPresContext* aPresContext,
                                     nsInputEvent* aSourceEvent,
                                     nsIContent* aTarget,
                                     bool aFullDispatch,
                                     uint32_t aFlags,
                                     nsEventStatus* aStatus);

  /**
   * Method to dispatch aEvent to aTarget. If aFullDispatch is true, the event
   * will be dispatched through the full dispatching of the presshell of the
   * aPresContext; if it's false the event will be dispatched only as a DOM
   * event.
   * If aPresContext is nullptr, this does nothing.
   */
  using nsIContent::DispatchEvent;
  static nsresult DispatchEvent(nsPresContext* aPresContext,
                                nsEvent* aEvent,
                                nsIContent* aTarget,
                                bool aFullDispatch,
                                nsEventStatus* aStatus);

  /**
   * Get the primary frame for this content with flushing
   *
   * @param aType the kind of flush to do, typically Flush_Frames or
   *              Flush_Layout
   * @return the primary frame
   */
  nsIFrame* GetPrimaryFrame(mozFlushType aType);
  // Work around silly C++ name hiding stuff
  nsIFrame* GetPrimaryFrame() const { return nsIContent::GetPrimaryFrame(); }

  /**
   * Struct that stores info on an attribute.  The name and value must
   * either both be null or both be non-null.
   */
  struct nsAttrInfo {
    nsAttrInfo(const nsAttrName* aName, const nsAttrValue* aValue) :
      mName(aName), mValue(aValue) {}
    nsAttrInfo(const nsAttrInfo& aOther) :
      mName(aOther.mName), mValue(aOther.mValue) {}

    const nsAttrName* mName;
    const nsAttrValue* mValue;
  };

  // Be careful when using this method. This does *NOT* handle
  // XUL prototypes. You may want to use GetAttrInfo.
  const nsAttrValue* GetParsedAttr(nsIAtom* aAttr) const
  {
    return mAttrsAndChildren.GetAttr(aAttr);
  }

  /**
   * Returns the attribute map, if there is one.
   *
   * @return existing attribute map or nullptr.
   */
  nsDOMAttributeMap *GetAttributeMap()
  {
    nsDOMSlots *slots = GetExistingDOMSlots();

    return slots ? slots->mAttributeMap.get() : nullptr;
  }

  virtual void RecompileScriptEventListeners()
  {
  }

  /**
   * Get the attr info for the given namespace ID and attribute name.  The
   * namespace ID must not be kNameSpaceID_Unknown and the name must not be
   * null.  Note that this can only return info on attributes that actually
   * live on this element (and is only virtual to handle XUL prototypes).  That
   * is, this should only be called from methods that only care about attrs
   * that effectively live in mAttrsAndChildren.
   */
  virtual nsAttrInfo GetAttrInfo(int32_t aNamespaceID, nsIAtom* aName) const;

  virtual void NodeInfoChanged(nsINodeInfo* aOldNodeInfo)
  {
  }

  /**
   * Parse a string into an nsAttrValue for a CORS attribute.  This
   * never fails.  The resulting value is an enumerated value whose
   * GetEnumValue() returns one of the above constants.
   */
  static void ParseCORSValue(const nsAString& aValue, nsAttrValue& aResult);

  /**
   * Return the CORS mode for a given string
   */
  static CORSMode StringToCORSMode(const nsAString& aValue);
  
  /**
   * Return the CORS mode for a given nsAttrValue (which may be null,
   * but if not should have been parsed via ParseCORSValue).
   */
  static CORSMode AttrValueToCORSMode(const nsAttrValue* aValue);

  // These are just used to implement nsIDOMElement using
  // NS_FORWARD_NSIDOMELEMENT_TO_GENERIC and for quickstubs.
  void
    GetElementsByTagName(const nsAString& aQualifiedName,
                         nsIDOMHTMLCollection** aResult);
  nsresult
    GetElementsByTagNameNS(const nsAString& aNamespaceURI,
                           const nsAString& aLocalName,
                           nsIDOMHTMLCollection** aResult);
  nsresult
    GetElementsByClassName(const nsAString& aClassNames,
                           nsIDOMHTMLCollection** aResult);
  void GetClassList(nsIDOMDOMTokenList** aClassList);

  virtual JSObject* WrapObject(JSContext *aCx, JSObject *aScope,
                               bool *aTriedToWrap) MOZ_FINAL;

protected:
  /*
   * Named-bools for use with SetAttrAndNotify to make call sites easier to
   * read.
   */
  static const bool kFireMutationEvent           = true;
  static const bool kDontFireMutationEvent       = false;
  static const bool kNotifyDocumentObservers     = true;
  static const bool kDontNotifyDocumentObservers = false;
  static const bool kCallAfterSetAttr            = true;
  static const bool kDontCallAfterSetAttr        = false;

  /**
   * Set attribute and (if needed) notify documentobservers and fire off
   * mutation events.  This will send the AttributeChanged notification.
   * Callers of this method are responsible for calling AttributeWillChange,
   * since that needs to happen before the new attr value has been set, and
   * in particular before it has been parsed.
   *
   * For the boolean parameters, consider using the named bools above to aid
   * code readability.
   *
   * @param aNamespaceID  namespace of attribute
   * @param aAttribute    local-name of attribute
   * @param aPrefix       aPrefix of attribute
   * @param aOldValue     previous value of attribute. Only needed if
   *                      aFireMutation is true.
   * @param aParsedValue  parsed new value of attribute
   * @param aModType      nsIDOMMutationEvent::MODIFICATION or ADDITION.  Only
   *                      needed if aFireMutation or aNotify is true.
   * @param aFireMutation should mutation-events be fired?
   * @param aNotify       should we notify document-observers?
   * @param aCallAfterSetAttr should we call AfterSetAttr?
   */
  nsresult SetAttrAndNotify(int32_t aNamespaceID,
                            nsIAtom* aName,
                            nsIAtom* aPrefix,
                            const nsAttrValue& aOldValue,
                            nsAttrValue& aParsedValue,
                            uint8_t aModType,
                            bool aFireMutation,
                            bool aNotify,
                            bool aCallAfterSetAttr);

  /**
   * Convert an attribute string value to attribute type based on the type of
   * attribute.  Called by SetAttr().  Note that at the moment we only do this
   * for attributes in the null namespace (kNameSpaceID_None).
   *
   * @param aNamespaceID the namespace of the attribute to convert
   * @param aAttribute the attribute to convert
   * @param aValue the string value to convert
   * @param aResult the nsAttrValue [OUT]
   * @return true if the parsing was successful, false otherwise
   */
  virtual bool ParseAttribute(int32_t aNamespaceID,
                                nsIAtom* aAttribute,
                                const nsAString& aValue,
                                nsAttrValue& aResult);

  /**
   * Try to set the attribute as a mapped attribute, if applicable.  This will
   * only be called for attributes that are in the null namespace and only on
   * attributes that returned true when passed to IsAttributeMapped.  The
   * caller will not try to set the attr in any other way if this method
   * returns true (the value of aRetval does not matter for that purpose).
   *
   * @param aDocument the current document of this node (an optimization)
   * @param aName the name of the attribute
   * @param aValue the nsAttrValue to set
   * @param [out] aRetval the nsresult status of the operation, if any.
   * @return true if the setting was attempted, false otherwise.
   */
  virtual bool SetMappedAttribute(nsIDocument* aDocument,
                                    nsIAtom* aName,
                                    nsAttrValue& aValue,
                                    nsresult* aRetval);

  /**
   * Hook that is called by Element::SetAttr to allow subclasses to
   * deal with attribute sets.  This will only be called after we verify that
   * we're actually doing an attr set and will be called before
   * AttributeWillChange and before ParseAttribute and hence before we've set
   * the new value.
   *
   * @param aNamespaceID the namespace of the attr being set
   * @param aName the localname of the attribute being set
   * @param aValue the value it's being set to represented as either a string or
   *        a parsed nsAttrValue. Alternatively, if the attr is being removed it
   *        will be null.
   * @param aNotify Whether we plan to notify document observers.
   */
  // Note that this is inlined so that when subclasses call it it gets
  // inlined.  Those calls don't go through a vtable.
  virtual nsresult BeforeSetAttr(int32_t aNamespaceID, nsIAtom* aName,
                                 const nsAttrValueOrString* aValue,
                                 bool aNotify)
  {
    return NS_OK;
  }

  /**
   * Hook that is called by Element::SetAttr to allow subclasses to
   * deal with attribute sets.  This will only be called after we have called
   * SetAndTakeAttr and AttributeChanged (that is, after we have actually set
   * the attr).  It will always be called under a scriptblocker.
   *
   * @param aNamespaceID the namespace of the attr being set
   * @param aName the localname of the attribute being set
   * @param aValue the value it's being set to.  If null, the attr is being
   *        removed.
   * @param aNotify Whether we plan to notify document observers.
   */
  // Note that this is inlined so that when subclasses call it it gets
  // inlined.  Those calls don't go through a vtable.
  virtual nsresult AfterSetAttr(int32_t aNamespaceID, nsIAtom* aName,
                                const nsAttrValue* aValue, bool aNotify)
  {
    return NS_OK;
  }

  /**
   * Hook to allow subclasses to produce a different nsEventListenerManager if
   * needed for attachment of attribute-defined handlers
   */
  virtual nsEventListenerManager*
    GetEventListenerManagerForAttr(nsIAtom* aAttrName, bool* aDefer);

  /**
   * Internal hook for converting an attribute name-string to an atomized name
   */
  virtual const nsAttrName* InternalGetExistingAttrNameFromQName(const nsAString& aStr) const;

  /**
   * Retrieve the rectangle for the offsetX properties, which
   * are coordinates relative to the returned element.
   *
   * @param aRect offset rectangle
   */
  virtual Element* GetOffsetRect(nsRect& aRect);

  /**
   * Retrieve the size of the padding rect of this element.
   *
   * @param aSize the size of the padding rect
   */
  nsIntSize GetPaddingRectSize();

  nsIFrame* GetStyledFrame();

  virtual Element* GetNameSpaceElement()
  {
    return this;
  }

  nsIDOMAttr* GetAttributeNodeNSInternal(const nsAString& aNamespaceURI,
                                         const nsAString& aLocalName,
                                         ErrorResult& aError);

  void RegisterFreezableElement() {
    OwnerDoc()->RegisterFreezableElement(this);
  }
  void UnregisterFreezableElement() {
    OwnerDoc()->UnregisterFreezableElement(this);
  }

  /**
   * Add/remove this element to the documents id cache
   */
  void AddToIdTable(nsIAtom* aId) {
    NS_ASSERTION(HasID(), "Node doesn't have an ID?");
    nsIDocument* doc = GetCurrentDoc();
    if (doc && (!IsInAnonymousSubtree() || doc->IsXUL())) {
      doc->AddToIdTable(this, aId);
    }
  }
  void RemoveFromIdTable() {
    if (HasID()) {
      nsIDocument* doc = GetCurrentDoc();
      if (doc) {
        nsIAtom* id = DoGetID();
        // id can be null during mutation events evilness. Also, XUL elements
        // loose their proto attributes during cc-unlink, so this can happen
        // during cc-unlink too.
        if (id) {
          doc->RemoveFromIdTable(this, DoGetID());
        }
      }
    }
  }

  /**
   * Functions to carry out event default actions for links of all types
   * (HTML links, XLinks, SVG "XLinks", etc.)
   */

  /**
   * Check that we meet the conditions to handle a link event
   * and that we are actually on a link.
   *
   * @param aVisitor event visitor
   * @param aURI the uri of the link, set only if the return value is true [OUT]
   * @return true if we can handle the link event, false otherwise
   */
  bool CheckHandleEventForLinksPrecondition(nsEventChainVisitor& aVisitor,
                                              nsIURI** aURI) const;

  /**
   * Handle status bar updates before they can be cancelled.
   */
  nsresult PreHandleEventForLinks(nsEventChainPreVisitor& aVisitor);

  /**
   * Handle default actions for link event if the event isn't consumed yet.
   */
  nsresult PostHandleEventForLinks(nsEventChainPostVisitor& aVisitor);

  /**
   * Get the target of this link element. Consumers should established that
   * this element is a link (probably using IsLink) before calling this
   * function (or else why call it?)
   *
   * Note: for HTML this gets the value of the 'target' attribute; for XLink
   * this gets the value of the xlink:_moz_target attribute, or failing that,
   * the value of xlink:show, converted to a suitably equivalent named target
   * (e.g. _blank).
   */
  virtual void GetLinkTarget(nsAString& aTarget);

private:
  /**
   * Get this element's client area rect in app units.
   * @return the frame's client area
   */
  nsRect GetClientAreaRect();

  nsIScrollableFrame* GetScrollFrame(nsIFrame **aStyledFrame = nullptr);

  // Data members
  nsEventStates mState;
};

NS_DEFINE_STATIC_IID_ACCESSOR(Element, NS_ELEMENT_IID)

} // namespace dom
} // namespace mozilla

inline mozilla::dom::Element* nsINode::AsElement()
{
  MOZ_ASSERT(IsElement());
  return static_cast<mozilla::dom::Element*>(this);
}

inline const mozilla::dom::Element* nsINode::AsElement() const
{
  MOZ_ASSERT(IsElement());
  return static_cast<const mozilla::dom::Element*>(this);
}

inline bool nsINode::HasAttributes() const
{
  return IsElement() && AsElement()->GetAttrCount() > 0;
}

/**
 * Macros to implement Clone(). _elementName is the class for which to implement
 * Clone.
 */
#define NS_IMPL_ELEMENT_CLONE(_elementName)                                 \
nsresult                                                                    \
_elementName::Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const        \
{                                                                           \
  *aResult = nullptr;                                                        \
  nsCOMPtr<nsINodeInfo> ni = aNodeInfo;                                     \
  _elementName *it = new _elementName(ni.forget());                         \
  if (!it) {                                                                \
    return NS_ERROR_OUT_OF_MEMORY;                                          \
  }                                                                         \
                                                                            \
  nsCOMPtr<nsINode> kungFuDeathGrip = it;                                   \
  nsresult rv = const_cast<_elementName*>(this)->CopyInnerTo(it);           \
  if (NS_SUCCEEDED(rv)) {                                                   \
    kungFuDeathGrip.swap(*aResult);                                         \
  }                                                                         \
                                                                            \
  return rv;                                                                \
}

#define NS_IMPL_ELEMENT_CLONE_WITH_INIT(_elementName)                       \
nsresult                                                                    \
_elementName::Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const        \
{                                                                           \
  *aResult = nullptr;                                                        \
  nsCOMPtr<nsINodeInfo> ni = aNodeInfo;                                     \
  _elementName *it = new _elementName(ni.forget());                         \
  if (!it) {                                                                \
    return NS_ERROR_OUT_OF_MEMORY;                                          \
  }                                                                         \
                                                                            \
  nsCOMPtr<nsINode> kungFuDeathGrip = it;                                   \
  nsresult rv = it->Init();                                                 \
  nsresult rv2 = const_cast<_elementName*>(this)->CopyInnerTo(it);          \
  if (NS_FAILED(rv2)) {                                                     \
    rv = rv2;                                                               \
  }                                                                         \
  if (NS_SUCCEEDED(rv)) {                                                   \
    kungFuDeathGrip.swap(*aResult);                                         \
  }                                                                         \
                                                                            \
  return rv;                                                                \
}

#define DOMCI_NODE_DATA(_interface, _class)                             \
  DOMCI_DATA(_interface, _class)                                        \
  nsXPCClassInfo* _class::GetClassInfo()                                \
  {                                                                     \
    return static_cast<nsXPCClassInfo*>(                                \
      NS_GetDOMClassInfoInstance(eDOMClassInfo_##_interface##_id));     \
  }

/**
 * A macro to implement the getter and setter for a given string
 * valued content property. The method uses the generic GetAttr and
 * SetAttr methods.  We use the 5-argument form of SetAttr, because
 * some consumers only implement that one, hiding superclass
 * 4-argument forms.
 */
#define NS_IMPL_STRING_ATTR(_class, _method, _atom)                     \
  NS_IMETHODIMP                                                         \
  _class::Get##_method(nsAString& aValue)                               \
  {                                                                     \
    GetAttr(kNameSpaceID_None, nsGkAtoms::_atom, aValue);               \
    return NS_OK;                                                       \
  }                                                                     \
  NS_IMETHODIMP                                                         \
  _class::Set##_method(const nsAString& aValue)                         \
  {                                                                     \
    return SetAttr(kNameSpaceID_None, nsGkAtoms::_atom, nullptr, aValue, true); \
  }

#define NS_FORWARD_NSIDOMELEMENT_TO_GENERIC                                   \
typedef mozilla::dom::Element Element;                                        \
NS_IMETHOD GetTagName(nsAString& aTagName) MOZ_FINAL                          \
{                                                                             \
  Element::GetTagName(aTagName);                                              \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetClassList(nsIDOMDOMTokenList** aClassList) MOZ_FINAL            \
{                                                                             \
  Element::GetClassList(aClassList);                                          \
  return NS_OK;                                                               \
}                                                                             \
using Element::GetAttribute;                                                  \
NS_IMETHOD GetAttribute(const nsAString& name, nsAString& _retval) MOZ_FINAL  \
{                                                                             \
  nsString attr;                                                              \
  GetAttribute(name, attr);                                                   \
  _retval = attr;                                                             \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetAttributeNS(const nsAString& namespaceURI,                      \
                          const nsAString& localName,                         \
                          nsAString& _retval) MOZ_FINAL                       \
{                                                                             \
  Element::GetAttributeNS(namespaceURI, localName, _retval);                  \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD SetAttribute(const nsAString& name,                                \
                        const nsAString& value)                               \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  Element::SetAttribute(name, value, rv);                                     \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD SetAttributeNS(const nsAString& namespaceURI,                      \
                          const nsAString& qualifiedName,                     \
                          const nsAString& value) MOZ_FINAL                   \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  Element::SetAttributeNS(namespaceURI, qualifiedName, value, rv);            \
  return rv.ErrorCode();                                                      \
}                                                                             \
using Element::RemoveAttribute;                                               \
NS_IMETHOD RemoveAttribute(const nsAString& name) MOZ_FINAL                   \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  RemoveAttribute(name, rv);                                                  \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD RemoveAttributeNS(const nsAString& namespaceURI,                   \
                             const nsAString& localName) MOZ_FINAL            \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  Element::RemoveAttributeNS(namespaceURI, localName, rv);                    \
  return rv.ErrorCode();                                                      \
}                                                                             \
using Element::HasAttribute;                                                  \
NS_IMETHOD HasAttribute(const nsAString& name,                                \
                           bool* _retval) MOZ_FINAL                           \
{                                                                             \
  *_retval = HasAttribute(name);                                              \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD HasAttributeNS(const nsAString& namespaceURI,                      \
                          const nsAString& localName,                         \
                          bool* _retval) MOZ_FINAL                            \
{                                                                             \
  *_retval = Element::HasAttributeNS(namespaceURI, localName);                \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetAttributeNode(const nsAString& name,                            \
                            nsIDOMAttr** _retval) MOZ_FINAL                   \
{                                                                             \
  NS_IF_ADDREF(*_retval = Element::GetAttributeNode(name));                   \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD SetAttributeNode(nsIDOMAttr* newAttr,                              \
                            nsIDOMAttr** _retval) MOZ_FINAL                   \
{                                                                             \
  if (!newAttr) {                                                             \
    return NS_ERROR_INVALID_POINTER;                                          \
  }                                                                           \
  mozilla::ErrorResult rv;                                                    \
  *_retval = Element::SetAttributeNode(newAttr, rv).get();                    \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD RemoveAttributeNode(nsIDOMAttr* oldAttr,                           \
                               nsIDOMAttr** _retval) MOZ_FINAL                \
{                                                                             \
  if (!oldAttr) {                                                             \
    return NS_ERROR_INVALID_POINTER;                                          \
  }                                                                           \
  mozilla::ErrorResult rv;                                                    \
  *_retval = Element::RemoveAttributeNode(oldAttr, rv).get();                 \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD GetAttributeNodeNS(const nsAString& namespaceURI,                  \
                              const nsAString& localName,                     \
                              nsIDOMAttr** _retval) MOZ_FINAL                 \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  NS_IF_ADDREF(*_retval = Element::GetAttributeNodeNS(namespaceURI,           \
                                                      localName,              \
                                                      rv));                   \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD SetAttributeNodeNS(nsIDOMAttr* newAttr,                            \
                              nsIDOMAttr** _retval) MOZ_FINAL                 \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  *_retval = Element::SetAttributeNodeNS(newAttr, rv).get();                  \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD GetElementsByTagName(const nsAString& name,                        \
                                nsIDOMHTMLCollection** _retval) MOZ_FINAL     \
{                                                                             \
  Element::GetElementsByTagName(name, _retval);                               \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetElementsByTagNameNS(const nsAString& namespaceURI,              \
                                  const nsAString& localName,                 \
                                  nsIDOMHTMLCollection** _retval) MOZ_FINAL   \
{                                                                             \
  return Element::GetElementsByTagNameNS(namespaceURI, localName,             \
                                         _retval);                            \
}                                                                             \
NS_IMETHOD GetElementsByClassName(const nsAString& classes,                   \
                                  nsIDOMHTMLCollection** _retval) MOZ_FINAL   \
{                                                                             \
  return Element::GetElementsByClassName(classes, _retval);                   \
}                                                                             \
NS_IMETHOD GetChildElements(nsIDOMNodeList** aChildElements) MOZ_FINAL        \
{                                                                             \
  nsIHTMLCollection* list = FragmentOrElement::Children();                    \
  return CallQueryInterface(list, aChildElements);                            \
}                                                                             \
NS_IMETHOD GetFirstElementChild(nsIDOMElement** aFirstElementChild) MOZ_FINAL \
{                                                                             \
  Element* element = Element::GetFirstElementChild();                         \
  if (!element) {                                                             \
    *aFirstElementChild = nullptr;                                            \
    return NS_OK;                                                             \
  }                                                                           \
  return CallQueryInterface(element, aFirstElementChild);                     \
}                                                                             \
NS_IMETHOD GetLastElementChild(nsIDOMElement** aLastElementChild) MOZ_FINAL   \
{                                                                             \
  Element* element = Element::GetLastElementChild();                          \
  if (!element) {                                                             \
    *aLastElementChild = nullptr;                                             \
    return NS_OK;                                                             \
  }                                                                           \
  return CallQueryInterface(element, aLastElementChild);                      \
}                                                                             \
NS_IMETHOD GetPreviousElementSibling(nsIDOMElement** aPreviousElementSibling) \
  MOZ_FINAL                                                                   \
{                                                                             \
  Element* element = Element::GetPreviousElementSibling();                    \
  if (!element) {                                                             \
    *aPreviousElementSibling = nullptr;                                       \
    return NS_OK;                                                             \
  }                                                                           \
  return CallQueryInterface(element, aPreviousElementSibling);                \
}                                                                             \
NS_IMETHOD GetNextElementSibling(nsIDOMElement** aNextElementSibling)         \
  MOZ_FINAL                                                                   \
{                                                                             \
  Element* element = Element::GetNextElementSibling();                        \
  if (!element) {                                                             \
    *aNextElementSibling = nullptr;                                           \
    return NS_OK;                                                             \
  }                                                                           \
  return CallQueryInterface(element, aNextElementSibling);                    \
}                                                                             \
NS_IMETHOD GetChildElementCount(uint32_t* aChildElementCount) MOZ_FINAL       \
{                                                                             \
  *aChildElementCount = Element::ChildElementCount();                         \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetOnmouseenter(JSContext* cx, JS::Value* aOnmouseenter) MOZ_FINAL \
{                                                                             \
  return Element::GetOnmouseenter(cx, aOnmouseenter);                         \
}                                                                             \
NS_IMETHOD SetOnmouseenter(JSContext* cx,                                     \
                           const JS::Value& aOnmouseenter) MOZ_FINAL          \
{                                                                             \
  return Element::SetOnmouseenter(cx, aOnmouseenter);                         \
}                                                                             \
NS_IMETHOD GetOnmouseleave(JSContext* cx, JS::Value* aOnmouseleave) MOZ_FINAL \
{                                                                             \
  return Element::GetOnmouseleave(cx, aOnmouseleave);                         \
}                                                                             \
NS_IMETHOD SetOnmouseleave(JSContext* cx,                                     \
                           const JS::Value& aOnmouseleave) MOZ_FINAL          \
{                                                                             \
  return Element::SetOnmouseleave(cx, aOnmouseleave);                         \
}                                                                             \
NS_IMETHOD GetClientRects(nsIDOMClientRectList** _retval) MOZ_FINAL           \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  *_retval = Element::GetClientRects(rv).get();                               \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD GetBoundingClientRect(nsIDOMClientRect** _retval) MOZ_FINAL        \
{                                                                             \
  *_retval = Element::GetBoundingClientRect().get();                          \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollTop(int32_t* aScrollTop) MOZ_FINAL                        \
{                                                                             \
  *aScrollTop = Element::ScrollTop();                                         \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD SetScrollTop(int32_t aScrollTop) MOZ_FINAL                         \
{                                                                             \
  Element::SetScrollTop(aScrollTop);                                          \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollLeft(int32_t* aScrollLeft) MOZ_FINAL                      \
{                                                                             \
  *aScrollLeft = Element::ScrollLeft();                                       \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD SetScrollLeft(int32_t aScrollLeft) MOZ_FINAL                       \
{                                                                             \
  Element::SetScrollLeft(aScrollLeft);                                        \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollWidth(int32_t* aScrollWidth) MOZ_FINAL                    \
{                                                                             \
  *aScrollWidth = Element::ScrollWidth();                                     \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollHeight(int32_t* aScrollHeight) MOZ_FINAL                  \
{                                                                             \
  *aScrollHeight = Element::ScrollHeight();                                   \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetClientTop(int32_t* aClientTop) MOZ_FINAL                        \
{                                                                             \
  *aClientTop = Element::ClientTop();                                         \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetClientLeft(int32_t* aClientLeft) MOZ_FINAL                      \
{                                                                             \
  *aClientLeft = Element::ClientLeft();                                       \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetClientWidth(int32_t* aClientWidth) MOZ_FINAL                    \
{                                                                             \
  *aClientWidth = Element::ClientWidth();                                     \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetClientHeight(int32_t* aClientHeight) MOZ_FINAL                  \
{                                                                             \
  *aClientHeight = Element::ClientHeight();                                   \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollLeftMax(int32_t* aScrollLeftMax) MOZ_FINAL                \
{                                                                             \
  *aScrollLeftMax = Element::ScrollLeftMax();                                 \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD GetScrollTopMax(int32_t* aScrollTopMax) MOZ_FINAL                  \
{                                                                             \
  *aScrollTopMax = Element::ScrollTopMax();                                   \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD MozMatchesSelector(const nsAString& selector,                      \
                              bool* _retval) MOZ_FINAL                        \
{                                                                             \
  mozilla::ErrorResult rv;                                                    \
  *_retval = Element::MozMatchesSelector(selector, rv);                       \
  return rv.ErrorCode();                                                      \
}                                                                             \
NS_IMETHOD SetCapture(bool retargetToElement) MOZ_FINAL                       \
{                                                                             \
  Element::SetCapture(retargetToElement);                                     \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD ReleaseCapture(void) MOZ_FINAL                                     \
{                                                                             \
  Element::ReleaseCapture();                                                  \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD MozRequestFullScreen(void) MOZ_FINAL                               \
{                                                                             \
  Element::MozRequestFullScreen();                                            \
  return NS_OK;                                                               \
}                                                                             \
NS_IMETHOD MozRequestPointerLock(void) MOZ_FINAL                              \
{                                                                             \
  Element::MozRequestPointerLock();                                           \
  return NS_OK;                                                               \
}

#endif // mozilla_dom_Element_h__
