/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* 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_HyperTextAccessible_h__ #define mozilla_a11y_HyperTextAccessible_h__ #include "AccessibleWrap.h" #include "nsIAccessibleText.h" #include "nsIAccessibleTypes.h" #include "nsDirection.h" #include "WordMovementType.h" #include "nsIFrame.h" #include "nsISelectionController.h" class nsFrameSelection; class nsRange; class nsIWidget; namespace mozilla { namespace dom { class Selection; } namespace a11y { class TextRange; struct DOMPoint { DOMPoint() : node(nullptr), idx(0) { } DOMPoint(nsINode* aNode, int32_t aIdx) : node(aNode), idx(aIdx) { } nsINode* node; int32_t idx; }; // This character marks where in the text returned via Text interface, // that embedded object characters exist const char16_t kEmbeddedObjectChar = 0xfffc; const char16_t kImaginaryEmbeddedObjectChar = ' '; const char16_t kForcedNewLineChar = '\n'; /** * Special Accessible that knows how contain both text and embedded objects */ class HyperTextAccessible : public AccessibleWrap { public: HyperTextAccessible(nsIContent* aContent, DocAccessible* aDoc); NS_DECL_ISUPPORTS_INHERITED // Accessible virtual nsIAtom* LandmarkRole() const override; virtual int32_t GetLevelInternal() override; virtual already_AddRefed NativeAttributes() override; virtual mozilla::a11y::role NativeRole() override; virtual uint64_t NativeState() override; virtual void InvalidateChildren() override; virtual bool RemoveChild(Accessible* aAccessible) override; // HyperTextAccessible (static helper method) // Convert content offset to rendered text offset nsresult ContentToRenderedOffset(nsIFrame *aFrame, int32_t aContentOffset, uint32_t *aRenderedOffset) const; // Convert rendered text offset to content offset nsresult RenderedToContentOffset(nsIFrame *aFrame, uint32_t aRenderedOffset, int32_t *aContentOffset) const; ////////////////////////////////////////////////////////////////////////////// // HyperLinkAccessible /** * Return link count within this hypertext accessible. */ uint32_t LinkCount() { return EmbeddedChildCount(); } /** * Return link accessible at the given index. */ Accessible* LinkAt(uint32_t aIndex) { return GetEmbeddedChildAt(aIndex); } /** * Return index for the given link accessible. */ int32_t LinkIndexOf(Accessible* aLink) { return GetIndexOfEmbeddedChild(aLink); } /** * Return link accessible at the given text offset. */ int32_t LinkIndexAtOffset(uint32_t aOffset) { Accessible* child = GetChildAtOffset(aOffset); return child ? LinkIndexOf(child) : -1; } ////////////////////////////////////////////////////////////////////////////// // HyperTextAccessible: DOM point to text offset conversions. /** * Turn a DOM point (node and offset) into a character offset of this * hypertext. Will look for closest match when the DOM node does not have * an accessible object associated with it. Will return an offset for the end * of the string if the node is not found. * * @param aNode [in] the node to look for * @param aNodeOffset [in] the offset to look for * if -1 just look directly for the node * if >=0 and aNode is text, this represents a char offset * if >=0 and aNode is not text, this represents a child node offset * @param aIsEndOffset [in] if true, then then this offset is not inclusive. The character * indicated by the offset returned is at [offset - 1]. This means * if the passed-in offset is really in a descendant, then the offset returned * will come just after the relevant embedded object characer. * If false, then the offset is inclusive. The character indicated * by the offset returned is at [offset]. If the passed-in offset in inside a * descendant, then the returned offset will be on the relevant embedded object char. */ uint32_t DOMPointToOffset(nsINode* aNode, int32_t aNodeOffset, bool aIsEndOffset = false) const; /** * Transform the given a11y point into the offset relative this hypertext. */ uint32_t TransformOffset(Accessible* aDescendant, uint32_t aOffset, bool aIsEndOffset) const; /** * Convert start and end hypertext offsets into DOM range. Note that if * aStartOffset and/or aEndOffset is in generated content such as ::before or * ::after, the result range excludes the generated content. See also * ClosestNotGeneratedDOMPoint() for more information. * * @param aStartOffset [in] the given start hypertext offset * @param aEndOffset [in] the given end hypertext offset * @param aRange [in, out] the range whose bounds to set * @return true if conversion was successful */ bool OffsetsToDOMRange(int32_t aStartOffset, int32_t aEndOffset, nsRange* aRange); /** * Convert the given offset into DOM point. * * If offset is at text leaf then DOM point is (text node, offsetInTextNode), * if before embedded object then (parent node, indexInParent), if after then * (parent node, indexInParent + 1). */ DOMPoint OffsetToDOMPoint(int32_t aOffset); /** * Return true if the used ARIA role (if any) allows the hypertext accessible * to expose text interfaces. */ bool IsTextRole(); ////////////////////////////////////////////////////////////////////////////// // TextAccessible /** * Return character count within the hypertext accessible. */ uint32_t CharacterCount() const { return GetChildOffset(ChildCount()); } /** * Get a character at the given offset (don't support magic offsets). */ bool CharAt(int32_t aOffset, nsAString& aChar, int32_t* aStartOffset = nullptr, int32_t* aEndOffset = nullptr) { NS_ASSERTION(!aStartOffset == !aEndOffset, "Offsets should be both defined or both undefined!"); int32_t childIdx = GetChildIndexAtOffset(aOffset); if (childIdx == -1) return false; Accessible* child = GetChildAt(childIdx); child->AppendTextTo(aChar, aOffset - GetChildOffset(childIdx), 1); if (aStartOffset && aEndOffset) { *aStartOffset = aOffset; *aEndOffset = aOffset + aChar.Length(); } return true; } char16_t CharAt(int32_t aOffset) { nsAutoString charAtOffset; CharAt(aOffset, charAtOffset); return charAtOffset.CharAt(0); } /** * Return true if char at the given offset equals to given char. */ bool IsCharAt(int32_t aOffset, char16_t aChar) { return CharAt(aOffset) == aChar; } /** * Return true if terminal char is at the given offset. */ bool IsLineEndCharAt(int32_t aOffset) { return IsCharAt(aOffset, '\n'); } /** * Return text between given offsets. */ void TextSubstring(int32_t aStartOffset, int32_t aEndOffset, nsAString& aText); /** * Return text before/at/after the given offset corresponding to * the boundary type. */ void TextBeforeOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType, int32_t* aStartOffset, int32_t* aEndOffset, nsAString& aText); void TextAtOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType, int32_t* aStartOffset, int32_t* aEndOffset, nsAString& aText); void TextAfterOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType, int32_t* aStartOffset, int32_t* aEndOffset, nsAString& aText); /** * Return text attributes for the given text range. */ already_AddRefed TextAttributes(bool aIncludeDefAttrs, int32_t aOffset, int32_t* aStartOffset, int32_t* aEndOffset); /** * Return text attributes applied to the accessible. */ already_AddRefed DefaultTextAttributes(); /** * Return text offset of the given child accessible within hypertext * accessible. * * @param aChild [in] accessible child to get text offset for * @param aInvalidateAfter [in, optional] indicates whether invalidate * cached offsets for next siblings of the child */ int32_t GetChildOffset(Accessible* aChild, bool aInvalidateAfter = false) const { int32_t index = GetIndexOf(aChild); return index == -1 ? -1 : GetChildOffset(index, aInvalidateAfter); } /** * Return text offset for the child accessible index. */ int32_t GetChildOffset(uint32_t aChildIndex, bool aInvalidateAfter = false) const; /** * Return child accessible at the given text offset. * * @param aOffset [in] the given text offset */ int32_t GetChildIndexAtOffset(uint32_t aOffset) const; /** * Return child accessible at the given text offset. * * @param aOffset [in] the given text offset */ Accessible* GetChildAtOffset(uint32_t aOffset) const { return GetChildAt(GetChildIndexAtOffset(aOffset)); } /** * Return true if the given offset/range is valid. */ bool IsValidOffset(int32_t aOffset); bool IsValidRange(int32_t aStartOffset, int32_t aEndOffset); /** * Return an offset at the given point. */ int32_t OffsetAtPoint(int32_t aX, int32_t aY, uint32_t aCoordType); /** * Return a rect of the given text range relative given coordinate system. */ nsIntRect TextBounds(int32_t aStartOffset, int32_t aEndOffset, uint32_t aCoordType = nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE); /** * Return a rect for character at given offset relative given coordinate * system. */ nsIntRect CharBounds(int32_t aOffset, uint32_t aCoordType) { int32_t endOffset = aOffset == static_cast(CharacterCount()) ? aOffset : aOffset + 1; return TextBounds(aOffset, endOffset, aCoordType); } /** * Get/set caret offset, if no caret then -1. */ int32_t CaretOffset() const; void SetCaretOffset(int32_t aOffset); /** * Provide the line number for the caret. * @return 1-based index for the line number with the caret */ int32_t CaretLineNumber(); /** * Return the caret rect and the widget containing the caret within this * text accessible. * * @param [out] the widget containing the caret * @return the caret rect */ nsIntRect GetCaretRect(nsIWidget** aWidget); /** * Return selected regions count within the accessible. */ int32_t SelectionCount(); /** * Return the start and end offset of the specified selection. */ bool SelectionBoundsAt(int32_t aSelectionNum, int32_t* aStartOffset, int32_t* aEndOffset); /* * Changes the start and end offset of the specified selection. * @return true if succeeded */ bool SetSelectionBoundsAt(int32_t aSelectionNum, int32_t aStartOffset, int32_t aEndOffset); /** * Adds a selection bounded by the specified offsets. * @return true if succeeded */ bool AddToSelection(int32_t aStartOffset, int32_t aEndOffset); /* * Removes the specified selection. * @return true if succeeded */ bool RemoveFromSelection(int32_t aSelectionNum); /** * Scroll the given text range into view. */ void ScrollSubstringTo(int32_t aStartOffset, int32_t aEndOffset, uint32_t aScrollType); /** * Scroll the given text range to the given point. */ void ScrollSubstringToPoint(int32_t aStartOffset, int32_t aEndOffset, uint32_t aCoordinateType, int32_t aX, int32_t aY); /** * Return a range that encloses the text control or the document this * accessible belongs to. */ void EnclosingRange(TextRange& aRange) const; /** * Return an array of disjoint ranges for selected text within the text control * or the document this accessible belongs to. */ void SelectionRanges(nsTArray* aRanges) const; /** * Return an array of disjoint ranges of visible text within the text control * or the document this accessible belongs to. */ void VisibleRanges(nsTArray* aRanges) const; /** * Return a range containing the given accessible. */ void RangeByChild(Accessible* aChild, TextRange& aRange) const; /** * Return a range containing an accessible at the given point. */ void RangeAtPoint(int32_t aX, int32_t aY, TextRange& aRange) const; ////////////////////////////////////////////////////////////////////////////// // EditableTextAccessible void ReplaceText(const nsAString& aText); void InsertText(const nsAString& aText, int32_t aPosition); void CopyText(int32_t aStartPos, int32_t aEndPos); void CutText(int32_t aStartPos, int32_t aEndPos); void DeleteText(int32_t aStartPos, int32_t aEndPos); void PasteText(int32_t aPosition); /** * Return the editor associated with the accessible. */ virtual already_AddRefed GetEditor() const; /** * Return DOM selection object for the accessible. */ dom::Selection* DOMSelection() const; protected: virtual ~HyperTextAccessible() { } // Accessible virtual ENameValueFlag NativeName(nsString& aName) override; virtual void CacheChildren() override; // HyperTextAccessible /** * Transform magic offset into text offset. */ index_t ConvertMagicOffset(int32_t aOffset) const; /** * Adjust an offset the caret stays at to get a text by line boundary. */ uint32_t AdjustCaretOffset(uint32_t aOffset) const; /** * Return true if caret is at end of line. */ bool IsCaretAtEndOfLine() const; /** * Return true if the given offset points to terminal empty line if any. */ bool IsEmptyLastLineOffset(int32_t aOffset) { return aOffset == static_cast(CharacterCount()) && IsLineEndCharAt(aOffset - 1); } /** * Return an offset of the found word boundary. */ uint32_t FindWordBoundary(uint32_t aOffset, nsDirection aDirection, EWordMovementType aWordMovementType) { return FindOffset(aOffset, aDirection, eSelectWord, aWordMovementType); } /** * Used to get begin/end of previous/this/next line. Note: end of line * is an offset right before '\n' character if any, the offset is right after * '\n' character is begin of line. In case of wrap word breaks these offsets * are equal. */ enum EWhichLineBoundary { ePrevLineBegin, ePrevLineEnd, eThisLineBegin, eThisLineEnd, eNextLineBegin, eNextLineEnd }; /** * Return an offset for requested line boundary. See constants above. */ uint32_t FindLineBoundary(uint32_t aOffset, EWhichLineBoundary aWhichLineBoundary); /** * Return an offset corresponding to the given direction and selection amount * relative the given offset. A helper used to find word or line boundaries. */ uint32_t FindOffset(uint32_t aOffset, nsDirection aDirection, nsSelectionAmount aAmount, EWordMovementType aWordMovementType = eDefaultBehavior); /** * Return the boundaries of the substring in case of textual frame or * frame boundaries in case of non textual frame, offsets are ignored. */ nsIntRect GetBoundsInFrame(nsIFrame* aFrame, uint32_t aStartRenderedOffset, uint32_t aEndRenderedOffset); // Selection helpers /** * Return frame selection object for the accessible. */ already_AddRefed FrameSelection() const; /** * Return selection ranges within the accessible subtree. */ void GetSelectionDOMRanges(int16_t aType, nsTArray* aRanges); nsresult SetSelectionRange(int32_t aStartPos, int32_t aEndPos); /** * Convert the given DOM point to a DOM point in non-generated contents. * * If aDOMPoint is in ::before, the result is immediately after it. * If aDOMPoint is in ::after, the result is immediately before it. * * @param aDOMPoint [in] A DOM node and an index of its child. This may * be in a generated content such as ::before or * ::after. * @param aElementContent [in] An nsIContent representing an element of * aDOMPoint.node. * @return An DOM point which must not be in generated * contents. */ DOMPoint ClosestNotGeneratedDOMPoint(const DOMPoint& aDOMPoint, nsIContent* aElementContent); // Helpers nsresult GetDOMPointByFrameOffset(nsIFrame* aFrame, int32_t aOffset, Accessible* aAccessible, mozilla::a11y::DOMPoint* aPoint); /** * Set 'misspelled' text attribute and return range offsets where the * attibute is stretched. If the text is not misspelled at the given offset * then we expose only range offsets where text is not misspelled. The method * is used by TextAttributes() method. * * @param aIncludeDefAttrs [in] points whether text attributes having default * values of attributes should be included * @param aSourceNode [in] the node we start to traverse from * @param aStartOffset [in, out] the start offset * @param aEndOffset [in, out] the end offset * @param aAttributes [out, optional] result attributes */ void GetSpellTextAttr(nsINode* aNode, int32_t aNodeOffset, uint32_t* aStartOffset, uint32_t* aEndOffset, nsIPersistentProperties* aAttributes); private: /** * End text offsets array. */ mutable nsTArray mOffsets; }; //////////////////////////////////////////////////////////////////////////////// // Accessible downcasting method inline HyperTextAccessible* Accessible::AsHyperText() { return IsHyperText() ? static_cast(this) : nullptr; } } // namespace a11y } // namespace mozilla #endif