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diff --git a/accessible/base/TextLeafRange.h b/accessible/base/TextLeafRange.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_TextLeafRange_h__
+#define mozilla_a11y_TextLeafRange_h__
+
+#include <stdint.h>
+
+#include "AccAttributes.h"
+#include "nsDirection.h"
+#include "nsIAccessibleText.h"
+
+class nsRange;
+
+namespace mozilla {
+namespace dom {
+class Document;
+}
+
+namespace a11y {
+class Accessible;
+class LocalAccessible;
+
+/**
+ * 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) {}
+
+  /**
+   * Construct a TextLeafPoint representing the caret.
+   * The actual offset used for the caret differs depending on whether the
+   * caret is at the end of a line and the query being made. Thus, mOffset on
+   * the returned TextLeafPoint is not a valid offset.
+   */
+  static TextLeafPoint GetCaret(Accessible* aAcc) {
+    return TextLeafPoint(aAcc, nsIAccessibleText::TEXT_OFFSET_CARET);
+  }
+
+  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;
+
+  bool operator<=(const TextLeafPoint& aPoint) const;
+
+  /**
+   * A valid TextLeafPoint evaluates to true. An invalid TextLeafPoint
+   * evaluates to false.
+   */
+  explicit operator bool() const { return !!mAcc; }
+
+  bool IsCaret() const {
+    return mOffset == nsIAccessibleText::TEXT_OFFSET_CARET;
+  }
+
+  bool IsCaretAtEndOfLine() const;
+
+  /**
+   * Get a TextLeafPoint at the actual caret offset.
+   * This should only be called on a TextLeafPoint created with GetCaret.
+   * If aAdjustAtEndOfLine is true, the point will be adjusted if the caret is
+   * at the end of a line so that word and line boundaries can be calculated
+   * correctly.
+   */
+  TextLeafPoint ActualizeCaret(bool aAdjustAtEndOfLine = true) const;
+
+  enum class BoundaryFlags : uint32_t {
+    eDefaultBoundaryFlags = 0,
+    // Return point unchanged if it is at the given boundary type.
+    eIncludeOrigin = 1 << 0,
+    // If current point is in editable, return point within samme editable.
+    eStopInEditable = 1 << 1,
+    // Skip over list items in searches and don't consider them line or
+    // paragraph starts.
+    eIgnoreListItemMarker = 1 << 2,
+  };
+
+  /**
+   * 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).
+   */
+  TextLeafPoint FindBoundary(
+      AccessibleTextBoundary aBoundaryType, nsDirection aDirection,
+      BoundaryFlags aFlags = BoundaryFlags::eDefaultBoundaryFlags) 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;
+
+  /**
+   * Get the offsets of all spelling errors in a given LocalAccessible. This
+   * should only be used when pushing the cache. Most callers will want
+   * FindTextAttrsStart instead.
+   */
+  static nsTArray<int32_t> GetSpellingErrorOffsets(LocalAccessible* aAcc);
+
+  /**
+   * Queue a cache update for a spelling error in a given DOM range.
+   */
+  static void UpdateCachedSpellingError(dom::Document* aDocument,
+                                        const nsRange& aRange);
+
+  /**
+   * 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.
+   */
+  TextLeafPoint FindTextAttrsStart(nsDirection aDirection,
+                                   bool aIncludeOrigin = false) const;
+
+  /**
+   * Returns a rect (in dev pixels) describing position and size of
+   * the character at mOffset in mAcc. This rect is screen-relative.
+   * This function only works on remote accessibles, and assumes caching
+   * is enabled.
+   */
+  LayoutDeviceIntRect CharBounds();
+
+  /**
+   * Returns true if the given point (in screen coords) is contained
+   * in the char bounds of the current TextLeafPoint. Returns false otherwise.
+   * If the current point is an empty container, we use the acc's bounds instead
+   * of char bounds. Because this depends on CharBounds, this function only
+   * works on remote accessibles, and assumes caching is enabled.
+   */
+  bool ContainsPoint(int32_t aX, int32_t aY);
+
+  bool IsLineFeedChar() const { return GetChar() == '\n'; }
+
+  bool IsSpace() const;
+
+  bool IsParagraphStart(bool aIgnoreListItemMarker = false) const {
+    return mOffset == 0 &&
+           FindParagraphSameAcc(eDirPrevious, true, aIgnoreListItemMarker);
+  }
+
+  /**
+   * Translate given TextLeafPoint into a DOM point.
+   */
+  MOZ_CAN_RUN_SCRIPT std::pair<nsIContent*, int32_t> ToDOMPoint(
+      bool aIncludeGenerated = true) const;
+
+ private:
+  bool IsEmptyLastLine() const;
+
+  bool IsDocEdge(nsDirection aDirection) const;
+
+  bool IsLeafAfterListItemMarker() const;
+
+  char16_t GetChar() 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,
+                                     bool aIgnoreListItemMarker = false) const;
+
+  TextLeafPoint FindLineEnd(nsDirection aDirection, BoundaryFlags aFlags) const;
+  TextLeafPoint FindWordEnd(nsDirection aDirection, BoundaryFlags aFlags) const;
+
+  TextLeafPoint FindParagraphSameAcc(nsDirection aDirection,
+                                     bool aIncludeOrigin,
+                                     bool aIgnoreListItemMarker = false) const;
+
+  bool IsInSpellingError() const;
+
+  /**
+   * Find a spelling error boundary in the same Accessible. This function
+   * searches for either start or end points, since either means a change in
+   * text attributes.
+   */
+  TextLeafPoint FindSpellingErrorSameAcc(nsDirection aDirection,
+                                         bool aIncludeOrigin) const;
+
+  // Return the point immediately succeeding or preceding this leaf depending
+  // on given direction.
+  TextLeafPoint NeighborLeafPoint(nsDirection aDirection, bool aIsEditable,
+                                  bool aIgnoreListItemMarker) const;
+
+  /**
+   * This function assumes mAcc is a LocalAccessible.
+   * It iterates the continuations of mAcc's primary frame until it locates
+   * the continuation containing mOffset (a rendered offset). It then uses
+   * GetScreenRectInAppUnits to compute screen coords for the frame, resizing
+   * such that the resulting rect contains only one character.
+   */
+  LayoutDeviceIntRect ComputeBoundsFromFrame() const;
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(TextLeafPoint::BoundaryFlags)
+
+/**
+ * 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) {}
+  explicit TextLeafRange() {}
+
+  /**
+   * A valid TextLeafRange evaluates to true. An invalid TextLeafRange
+   * evaluates to false.
+   */
+  explicit operator bool() const { return !!mStart && !!mEnd; }
+
+  bool operator!=(const TextLeafRange& aOther) const {
+    return mEnd != aOther.mEnd || mStart != aOther.mStart;
+  }
+
+  bool operator==(const TextLeafRange& aOther) const {
+    return mEnd == aOther.mEnd && mStart == aOther.mStart;
+  }
+
+  TextLeafPoint Start() const { return mStart; }
+  void SetStart(const TextLeafPoint& aStart) { mStart = aStart; }
+  TextLeafPoint End() const { return mEnd; }
+  void SetEnd(const TextLeafPoint& aEnd) { mEnd = aEnd; }
+
+  bool Crop(Accessible* aContainer);
+
+  /**
+   * Returns a union rect (in dev pixels) of all character bounds in this range.
+   * This rect is screen-relative and inclusive of mEnd. This function only
+   * works on remote accessibles, and assumes caching is enabled.
+   */
+  LayoutDeviceIntRect Bounds() const;
+
+  /**
+   * Set range as DOM selection.
+   * aSelectionNum is the selection index to use. If aSelectionNum is
+   * out of bounds for current selection ranges, or is -1, a new selection
+   * range is created.
+   */
+  MOZ_CAN_RUN_SCRIPT bool SetSelection(int32_t aSelectionNum) const;
+
+  MOZ_CAN_RUN_SCRIPT void ScrollIntoView(uint32_t aScrollType) const;
+
+ private:
+  TextLeafPoint mStart;
+  TextLeafPoint mEnd;
+
+ public:
+  /**
+   * A TextLeafRange iterator will iterate through single leaf segments of the
+   * given range.
+   */
+
+  class Iterator {
+   public:
+    Iterator(Iterator&& aOther)
+        : mRange(aOther.mRange),
+          mSegmentStart(aOther.mSegmentStart),
+          mSegmentEnd(aOther.mSegmentEnd) {}
+
+    static Iterator BeginIterator(const TextLeafRange& aRange);
+
+    static Iterator EndIterator(const TextLeafRange& aRange);
+
+    Iterator& operator++();
+
+    bool operator!=(const Iterator& aOther) const {
+      return mRange != aOther.mRange || mSegmentStart != aOther.mSegmentStart ||
+             mSegmentEnd != aOther.mSegmentEnd;
+    }
+
+    TextLeafRange operator*() {
+      return TextLeafRange(mSegmentStart, mSegmentEnd);
+    }
+
+   private:
+    explicit Iterator(const TextLeafRange& aRange) : mRange(aRange) {}
+
+    Iterator() = delete;
+    Iterator(const Iterator&) = delete;
+    Iterator& operator=(const Iterator&) = delete;
+    Iterator& operator=(const Iterator&&) = delete;
+
+    const TextLeafRange& mRange;
+    TextLeafPoint mSegmentStart;
+    TextLeafPoint mSegmentEnd;
+  };
+
+  Iterator begin() const { return Iterator::BeginIterator(*this); }
+  Iterator end() const { return Iterator::EndIterator(*this); }
+};
+
+}  // namespace a11y
+}  // namespace mozilla
+
+#endif