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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_TextLeafRange_h__
#define mozilla_a11y_TextLeafRange_h__
#include <stdint.h>
#include "AccAttributes.h"
#include "nsDirection.h"
#include "nsIAccessibleText.h"
namespace mozilla::a11y {
class Accessible;
/**
* Represents a point within accessible text.
* This is stored as a leaf Accessible and an offset into that Accessible.
* For an empty Accessible, the offset will always be 0.
* This will eventually replace TextPoint. Unlike TextPoint, this does not
* use HyperTextAccessible offsets.
*/
class TextLeafPoint final {
public:
TextLeafPoint(Accessible* aAcc, int32_t aOffset);
/**
* Constructs an invalid TextPoint (mAcc is null).
* A TextLeafPoint in this state will evaluate to false.
* mAcc can be set later. Alternatively, this can be used to indicate an error
* (e.g. if a requested point couldn't be found).
*/
TextLeafPoint() : mAcc(nullptr), mOffset(0) {}
Accessible* mAcc;
int32_t mOffset;
bool operator==(const TextLeafPoint& aPoint) const {
return mAcc == aPoint.mAcc && mOffset == aPoint.mOffset;
}
bool operator!=(const TextLeafPoint& aPoint) const {
return !(*this == aPoint);
}
bool operator<(const TextLeafPoint& aPoint) const;
/**
* A valid TextLeafPoint evaluates to true. An invalid TextLeafPoint
* evaluates to false.
*/
explicit operator bool() const { return !!mAcc; }
/**
* Find a boundary (word start, line start, etc.) in a specific direction.
* If no boundary is found, the start/end of the document is returned
* (depending on the direction).
* If aIncludeorigin is true and this is at a boundary, this will be
* returned unchanged.
*/
TextLeafPoint FindBoundary(AccessibleTextBoundary aBoundaryType,
nsDirection aDirection,
bool aIncludeOrigin = false) const;
/**
* These two functions find a line start boundary within the same
* LocalAccessible as this. That is, they do not cross Accessibles. If no
* boundary is found, an invalid TextLeafPoint is returned.
* These are used by FindBoundary. Most callers will want FindBoundary
* instead.
*/
TextLeafPoint FindPrevLineStartSameLocalAcc(bool aIncludeOrigin) const;
TextLeafPoint FindNextLineStartSameLocalAcc(bool aIncludeOrigin) const;
/**
* These two functions find a word start boundary within the same
* Accessible as this. That is, they do not cross Accessibles. If no
* boundary is found, an invalid TextLeafPoint is returned.
* These are used by FindBoundary. Most callers will want FindBoundary
* instead.
*/
TextLeafPoint FindPrevWordStartSameAcc(bool aIncludeOrigin) const;
TextLeafPoint FindNextWordStartSameAcc(bool aIncludeOrigin) const;
/**
* Get the text attributes at this point.
* If aIncludeDefaults is true, default attributes on the HyperTextAccessible
* will be included.
*/
already_AddRefed<AccAttributes> GetTextAttributes(
bool aIncludeDefaults = true) const;
/**
* Get Get the text attributes at this point in a LocalAccessible.
* This is used by GetTextAttributes. Most callers will want GetTextAttributes
* instead.
*/
already_AddRefed<AccAttributes> GetTextAttributesLocalAcc(
bool aIncludeDefaults = true) const;
/**
* Find the start of a run of text attributes in a specific direction.
* A text attributes run is a span of text where the attributes are the same.
* If no boundary is found, the start/end of the container is returned
* (depending on the direction).
* If aIncludeorigin is true and this is at a boundary, this will be
* returned unchanged.
* aOriginAttrs allows the caller to supply the text attributes for this (as
* retrieved by GetTextAttributes). This can be used to avoid fetching the
* attributes twice if they are also to be used for something else; e.g.
* returning the attributes to a client. If aOriginAttrs is null, this method
* will fetch the attributes itself.
* aIncludeDefaults specifies whether aOriginAttrs includes default
* attributes.
*/
TextLeafPoint FindTextAttrsStart(nsDirection aDirection,
bool aIncludeOrigin = false,
const AccAttributes* aOriginAttrs = nullptr,
bool aIncludeDefaults = true) const;
private:
bool IsEmptyLastLine() const;
TextLeafPoint FindLineStartSameRemoteAcc(nsDirection aDirection,
bool aIncludeOrigin) const;
/**
* Helper which just calls the appropriate function based on whether mAcc
*is local or remote.
*/
TextLeafPoint FindLineStartSameAcc(nsDirection aDirection,
bool aIncludeOrigin) const;
};
/**
* Represents a range of accessible text.
* This will eventually replace TextRange.
*/
class TextLeafRange final {
public:
TextLeafRange(const TextLeafPoint& aStart, const TextLeafPoint& aEnd)
: mStart(aStart), mEnd(aEnd) {}
explicit TextLeafRange(const TextLeafPoint& aStart)
: mStart(aStart), mEnd(aStart) {}
TextLeafPoint Start() { return mStart; }
void SetStart(const TextLeafPoint& aStart) { mStart = aStart; }
TextLeafPoint End() { return mEnd; }
void SetEnd(const TextLeafPoint& aEnd) { mEnd = aEnd; }
private:
TextLeafPoint mStart;
TextLeafPoint mEnd;
};
} // namespace mozilla::a11y
#endif