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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
* file, You can obtain one at */
#ifndef mozilla_SelectionChangeEventDispatcher_h
#define mozilla_SelectionChangeEventDispatcher_h
#include "mozilla/Attributes.h"
#include "nsCycleCollectionParticipant.h"
#include "nsTArray.h"
#include "nsCOMPtr.h"
#include "nsDirection.h"
class nsINode;
class nsRange;
namespace mozilla {
namespace dom {
class Document;
class Selection;
} // namespace dom
class SelectionChangeEventDispatcher final {
// SelectionChangeEventDispatcher has to participate in cycle collection
// because it holds strong references to nsINodes in its mOldRanges array.
void OnSelectionChange(dom::Document* aDocument, dom::Selection* aSelection,
int16_t aReason);
// This field is used to keep track of the ranges which were present in the
// selection when the selectionchange event was previously fired. This allows
// for the selectionchange event to only be fired when a selection is actually
// changed.
struct RawRangeData {
// These properties are not void*s to avoid the potential situation where
// the nsINode is freed, and a new nsINode is allocated with the same
// address, which could potentially break the comparison logic. In reality,
// this is extremely unlikely to occur (potentially impossible), but these
// nsCOMPtrs are safer. They are never dereferenced.
nsCOMPtr<nsINode> mStartContainer;
nsCOMPtr<nsINode> mEndContainer;
// XXX These are int32_ts on nsRange, but uint32_ts in the return value
// of GetStart_, so I use uint32_ts here. See bug 1194256.
uint32_t mStartOffset;
uint32_t mEndOffset;
explicit RawRangeData(const nsRange* aRange);
bool Equals(const nsRange* aRange);
nsTArray<RawRangeData> mOldRanges;
nsDirection mOldDirection;
~SelectionChangeEventDispatcher() = default;
} // namespace mozilla
#endif // mozilla_SelectionChangeEventDispatcher_h