gecko-dev/accessible/base/TextRange.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=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 http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_a11y_TextRange_h__
#define mozilla_a11y_TextRange_h__
#include <utility>
#include "nsTArray.h"
class nsRange;
namespace mozilla {
namespace dom {
class Selection;
} // namespace dom
namespace a11y {
class Accessible;
class LocalAccessible;
/**
* A text point (HyperText + offset), represents a boundary of text range.
* In new code, This should only be used when you explicitly need to deal with
* HyperText containers and offsets, including embedded objects; e.g. for
* IAccessible2 and ATK. Otherwise, use TextLeafPoint instead.
*/
struct TextPoint final {
TextPoint(Accessible* aContainer, int32_t aOffset)
: mContainer(aContainer), mOffset(aOffset) {}
TextPoint(const TextPoint& aPoint)
: mContainer(aPoint.mContainer), mOffset(aPoint.mOffset) {}
Accessible* mContainer;
int32_t mOffset;
bool operator==(const TextPoint& aPoint) const {
return mContainer == aPoint.mContainer && mOffset == aPoint.mOffset;
}
bool operator<(const TextPoint& aPoint) const;
};
/**
* Represents a HyperText range within the text control or document.
* In new code, This should only be used when you explicitly need to deal with
* HyperText containers and offsets, including embedded objects; e.g. for
* IAccessible2 and ATK. Otherwise, use TextLeafRange instead.
*/
class TextRange final {
public:
TextRange(Accessible* aRoot, Accessible* aStartContainer,
int32_t aStartOffset, Accessible* aEndContainer,
int32_t aEndOffset);
TextRange() : mStartOffset{0}, mEndOffset{0} {}
TextRange(TextRange&& aRange)
: mRoot(std::move(aRange.mRoot)),
mStartContainer(std::move(aRange.mStartContainer)),
mEndContainer(std::move(aRange.mEndContainer)),
mStartOffset(aRange.mStartOffset),
mEndOffset(aRange.mEndOffset) {}
TextRange& operator=(TextRange&& aRange) {
mRoot = std::move(aRange.mRoot);
mStartContainer = std::move(aRange.mStartContainer);
mEndContainer = std::move(aRange.mEndContainer);
mStartOffset = aRange.mStartOffset;
mEndOffset = aRange.mEndOffset;
return *this;
}
Accessible* Root() { return mRoot; }
Accessible* StartContainer() const { return mStartContainer; }
int32_t StartOffset() const { return mStartOffset; }
Accessible* EndContainer() const { return mEndContainer; }
int32_t EndOffset() const { return mEndOffset; }
bool operator==(const TextRange& aRange) const {
return mStartContainer == aRange.mStartContainer &&
mStartOffset == aRange.mStartOffset &&
mEndContainer == aRange.mEndContainer &&
mEndOffset == aRange.mEndOffset;
}
TextPoint StartPoint() const {
return TextPoint(mStartContainer, mStartOffset);
}
TextPoint EndPoint() const { return TextPoint(mEndContainer, mEndOffset); }
/**
* Return a container containing both start and end points.
*/
Accessible* Container() const;
/**
* Crops the range if it overlaps the given accessible element boundaries,
* returns true if the range was cropped successfully.
*/
bool Crop(Accessible* aContainer);
/**
* Convert stored hypertext offsets into DOM offsets and assign it to DOM
* range.
*
* Note that if start and/or end accessible offsets are in generated content
* such as ::before or
* ::after, the result range excludes the generated content. See also
* ClosestNotGeneratedDOMPoint() for more information.
*
* @param aRange [in, out] the range whose bounds to set
* @param aReversed [out] whether the start/end offsets were reversed.
* @return true if conversion was successful
*/
bool AssignDOMRange(nsRange* aRange, bool* aReversed = nullptr) const;
/**
* Return true if this TextRange object represents an actual range of text.
*/
bool IsValid() const { return mRoot; }
void SetStartPoint(Accessible* aContainer, int32_t aOffset) {
mStartContainer = aContainer;
mStartOffset = aOffset;
}
void SetEndPoint(Accessible* aContainer, int32_t aOffset) {
mStartContainer = aContainer;
mStartOffset = aOffset;
}
static void TextRangesFromSelection(dom::Selection* aSelection,
nsTArray<TextRange>* aRanges);
private:
TextRange(const TextRange& aRange) = delete;
TextRange& operator=(const TextRange& aRange) = delete;
friend class HyperTextAccessible;
friend class xpcAccessibleTextRange;
void Set(Accessible* aRoot, Accessible* aStartContainer, int32_t aStartOffset,
Accessible* aEndContainer, int32_t aEndOffset);
/**
* A helper method returning a common parent for two given accessible
* elements.
*/
Accessible* CommonParent(Accessible* aAcc1, Accessible* aAcc2,
nsTArray<Accessible*>* aParents1, uint32_t* aPos1,
nsTArray<Accessible*>* aParents2,
uint32_t* aPos2) const;
Accessible* mRoot;
Accessible* mStartContainer;
Accessible* mEndContainer;
int32_t mStartOffset;
int32_t mEndOffset;
};
} // namespace a11y
} // namespace mozilla
#endif