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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#ifndef DOM_SVG_DOMSVGNUMBERLIST_H_
#define DOM_SVG_DOMSVGNUMBERLIST_H_
#include "DOMSVGAnimatedNumberList.h"
#include "mozAutoDocUpdate.h"
#include "nsCycleCollectionParticipant.h"
#include "nsDebug.h"
#include "nsTArray.h"
#include "SVGNumberList.h"
#include "mozilla/Attributes.h"
#include "mozilla/RefPtr.h"
namespace mozilla {
class ErrorResult;
namespace dom {
class DOMSVGNumber;
class SVGElement;
//----------------------------------------------------------------------
// Helper class: AutoChangeNumberListNotifier
// Stack-based helper class to pair calls to WillChangeNumberList and
// DidChangeNumberList. Used by DOMSVGNumber and DOMSVGNumberList.
template <class T>
class MOZ_RAII AutoChangeNumberListNotifier : public mozAutoDocUpdate {
public:
explicit AutoChangeNumberListNotifier(T* aValue)
: mozAutoDocUpdate(aValue->Element()->GetComposedDoc(), true),
mValue(aValue) {
MOZ_ASSERT(mValue, "Expecting non-null value");
mEmptyOrOldValue =
mValue->Element()->WillChangeNumberList(mValue->AttrEnum(), *this);
}
~AutoChangeNumberListNotifier() {
mValue->Element()->DidChangeNumberList(mValue->AttrEnum(), mEmptyOrOldValue,
*this);
if (mValue->IsAnimating()) {
mValue->Element()->AnimationNeedsResample();
}
}
private:
T* const mValue;
nsAttrValue mEmptyOrOldValue;
};
/**
* Class DOMSVGNumberList
*
* This class is used to create the DOM tearoff objects that wrap internal
* SVGNumberList objects.
*
* See the architecture comment in DOMSVGAnimatedNumberList.h.
*
* This class is strongly intertwined with DOMSVGAnimatedNumberList and
* DOMSVGNumber. We are a friend of DOMSVGAnimatedNumberList, and are
* responsible for nulling out our DOMSVGAnimatedNumberList's pointer to us
* when we die, essentially making its pointer to us a weak pointer. Similarly,
* our DOMSVGNumber items are friends of us and responsible for nulling out our
* pointers to them.
*
* Our DOM items are created lazily on demand as and when script requests them.
*/
class DOMSVGNumberList final : public nsISupports, public nsWrapperCache {
template <class T>
friend class AutoChangeNumberListNotifier;
friend class DOMSVGNumber;
~DOMSVGNumberList() {
// Our mAList's weak ref to us must be nulled out when we die. If GC has
// unlinked us using the cycle collector code, then that has already
// happened, and mAList is null.
if (mAList) {
(IsAnimValList() ? mAList->mAnimVal : mAList->mBaseVal) = nullptr;
}
}
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(DOMSVGNumberList)
DOMSVGNumberList(DOMSVGAnimatedNumberList* aAList,
const SVGNumberList& aInternalList)
: mAList(aAList) {
// aInternalList must be passed in explicitly because we can't use
// InternalList() here. (Because it depends on IsAnimValList, which depends
// on this object having been assigned to aAList's mBaseVal or mAnimVal,
// which hasn't happened yet.)
InternalListLengthWillChange(aInternalList.Length()); // Sync mItems
}
JSObject* WrapObject(JSContext* cx,
JS::Handle<JSObject*> aGivenProto) override;
nsISupports* GetParentObject() { return static_cast<nsIContent*>(Element()); }
/**
* This will normally be the same as InternalList().Length(), except if we've
* hit OOM in which case our length will be zero.
*/
uint32_t LengthNoFlush() const {
MOZ_ASSERT(
mItems.Length() == 0 || mItems.Length() == InternalList().Length(),
"DOM wrapper's list length is out of sync");
return mItems.Length();
}
/// Called to notify us to synchronize our length and detach excess items.
void InternalListLengthWillChange(uint32_t aNewLength);
/**
* Returns true if our attribute is animating (in which case our animVal is
* not simply a mirror of our baseVal).
*/
bool IsAnimating() const { return mAList->IsAnimating(); }
/**
* Returns true if there is an animated list mirroring the base list.
*/
bool AnimListMirrorsBaseList() const {
return mAList->mAnimVal && !mAList->IsAnimating();
}
uint32_t NumberOfItems() const {
if (IsAnimValList()) {
Element()->FlushAnimations();
}
return LengthNoFlush();
}
void Clear(ErrorResult& error);
already_AddRefed<DOMSVGNumber> Initialize(DOMSVGNumber& aItem,
ErrorResult& error);
already_AddRefed<DOMSVGNumber> GetItem(uint32_t index, ErrorResult& error);
already_AddRefed<DOMSVGNumber> IndexedGetter(uint32_t index, bool& found,
ErrorResult& error);
already_AddRefed<DOMSVGNumber> InsertItemBefore(DOMSVGNumber& aItem,
uint32_t index,
ErrorResult& error);
already_AddRefed<DOMSVGNumber> ReplaceItem(DOMSVGNumber& aItem,
uint32_t index,
ErrorResult& error);
already_AddRefed<DOMSVGNumber> RemoveItem(uint32_t index, ErrorResult& error);
already_AddRefed<DOMSVGNumber> AppendItem(DOMSVGNumber& newItem,
ErrorResult& error) {
return InsertItemBefore(newItem, LengthNoFlush(), error);
}
uint32_t Length() const { return NumberOfItems(); }
private:
dom::SVGElement* Element() const { return mAList->mElement; }
uint8_t AttrEnum() const { return mAList->mAttrEnum; }
/// Used to determine if this list is the baseVal or animVal list.
bool IsAnimValList() const {
MOZ_ASSERT(this == mAList->mBaseVal || this == mAList->mAnimVal,
"Calling IsAnimValList() too early?!");
return this == mAList->mAnimVal;
}
/**
* Get a reference to this object's corresponding internal SVGNumberList.
*
* To simplify the code we just have this one method for obtaining both
* baseVal and animVal internal lists. This means that animVal lists don't
* get const protection, but our setter methods guard against changing
* animVal lists.
*/
SVGNumberList& InternalList() const;
/// Returns the DOMSVGNumber at aIndex, creating it if necessary.
already_AddRefed<DOMSVGNumber> GetItemAt(uint32_t aIndex);
void MaybeInsertNullInAnimValListAt(uint32_t aIndex);
void MaybeRemoveItemFromAnimValListAt(uint32_t aIndex);
// Weak refs to our DOMSVGNumber items. The items are friends and take care
// of clearing our pointer to them when they die.
FallibleTArray<DOMSVGNumber*> mItems;
RefPtr<DOMSVGAnimatedNumberList> mAList;
};
} // namespace dom
} // namespace mozilla
#endif // DOM_SVG_DOMSVGNUMBERLIST_H_