dom/base/Selection.h
author Emilio Cobos Álvarez <emilio@crisal.io>
Mon, 26 Nov 2018 09:21:37 +0000
changeset 504393 8e88421b280c2afda62f4ba704ce29701c30549f
parent 504376 14d532b8d89432c1a4b01d5007960295a13022da
child 504652 fb09acfff1684500e989acc798e97fa7f9358dc0
permissions -rw-r--r--
Bug 1506547 - Align user-select behavior more with other UAs. r=mats There's a few subtle behavior changes here, which I'll try to break down in the commit message. The biggest one is the EditableDescendantCount stuff going away. This was added in bug 1181130, to prevent clicking on the non-editable div from selecting the editable div inside. This is problematic for multiple reasons: * First, I don't think non-editable regions of an editable element should be user-select: all. * Second, it just doesn't work in Shadow DOM (the editable descendant count is not kept up-to-date when not in the uncomposed doc), so nested contenteditables behave differently inside vs. outside a Shadow Tree. * Third, I think it's user hostile to just entirely disable selection if you have a contenteditable descendant as a child of a user-select: all thing. WebKit behaves like this patch in the following test-case (though not Blink): https://crisal.io/tmp/user-select-all-contenteditable-descendant.html Edge doesn't seem to support user-select: all at all (no pun intended). But we don't allow to select anything at all which looks wrong. * Fourth, it's not tested at all (which explains how we broke it in Shadow DOM and not even notice...). In any case I've verified that this doesn't regress the editor from that bug. If this regresses anything we can fix it as outlined in the first bullet point above, which should also make us more compatible with other UAs in that test-case. The other change is `all` not overriding everything else. So, something like: <div style="-webkit-user-select: all">All <div style="-webkit-user-select: none">None</div></div> Totally ignores the -webkit-user-select: none declaration in Firefox before this change. This doesn't match any other UA nor the spec, and this patch aligns us with WebKit / Blink. This in turn makes us not need -moz-text anymore, whose only purpose was to avoid this. This also fixes a variety of bugs uncovered by the previous changes, like the SetIgnoreUserModify(false) call in editor being completely useless, since presShell->SetCaretEnabled ended in nsCaret::SetVisible, which overrode it. This in turn uncovered even more bugs, from bugs in the caret painting code, like not checking -moz-user-modify on the right frame if you're the last frame of a line, to even funnier bits where before this patch you show the caret but can't write at all... In any case, the new setup I came up with is that when you're editing (the selection is focused on an editable node) moving the caret forces it to end up in an editable node, thus jumping over non-editable ones. This has the nice effect of not completely disabling selection of -moz-user-select: all elements that have editable descendants (which was a very ad-hoc hack for bug 1181130, and somewhat broken per the above), and also not needing the -moz-user-select: all for non-editable bits in contenteditable.css at all. This also fixes issues with br-skipping like not being able to insert content in the following test-case: <div contenteditable="true"><span contenteditable="false">xyz </span><br>editable</div> If you start moving to the left from the second line, for example. I think this yields way better behavior in all the relevant test-cases from bug 1181130 / bug 1109968 / bug 1132768, shouldn't cause any regression, and the complexity is significantly reduced in some places. There's still some other broken bits that this patch doesn't fix, but I'll file follow-ups for those. Differential Revision: https://phabricator.services.mozilla.com/D12687

/* -*- 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 http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_Selection_h__
#define mozilla_Selection_h__

#include "nsIWeakReference.h"

#include "mozilla/AccessibleCaretEventHub.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/RangeBoundary.h"
#include "mozilla/SelectionChangeEventDispatcher.h"
#include "mozilla/TextRange.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/WeakPtr.h"
#include "nsDirection.h"
#include "nsIPresShell.h"  // For ScrollAxis
#include "nsISelectionController.h"
#include "nsISelectionListener.h"
#include "nsRange.h"
#include "nsTArrayForwardDeclare.h"
#include "nsThreadUtils.h"
#include "nsWrapperCache.h"

struct CachedOffsetForFrame;
class nsAutoScrollTimer;
class nsIContentIterator;
class nsIDocument;
class nsIFrame;
class nsFrameSelection;
class nsPIDOMWindowOuter;
struct SelectionDetails;
struct SelectionCustomColors;
class nsCopySupport;
class nsHTMLCopyEncoder;

namespace mozilla {
class ErrorResult;
class HTMLEditor;
enum class TableSelection : uint32_t;
struct AutoPrepareFocusRange;
namespace dom {
class DocGroup;
} // namespace dom
} // namespace mozilla

struct RangeData
{
  explicit RangeData(nsRange* aRange)
    : mRange(aRange)
  {}

  RefPtr<nsRange> mRange;
  mozilla::TextRangeStyle mTextRangeStyle;
};

namespace mozilla {
namespace dom {

// Note, the ownership of mozilla::dom::Selection depends on which way the
// object is created. When nsFrameSelection has created Selection,
// addreffing/releasing the Selection object is aggregated to nsFrameSelection.
// Otherwise normal addref/release is used.  This ensures that nsFrameSelection
// is never deleted before its Selections.
class Selection final : public nsSupportsWeakReference,
                        public nsWrapperCache,
                        public SupportsWeakPtr<Selection>
{
protected:
  virtual ~Selection();

public:
  Selection();
  explicit Selection(nsFrameSelection *aList);

  MOZ_DECLARE_WEAKREFERENCE_TYPENAME(Selection)

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(Selection)

  // match this up with EndbatchChanges. will stop ui updates while multiple
  // selection methods are called
  void StartBatchChanges();

  // match this up with StartBatchChanges
  void EndBatchChanges(int16_t aReason = nsISelectionListener::NO_REASON);

  /**
   * NotifyAutoCopy() starts to notify AutoCopyListener of selection changes.
   */
  void NotifyAutoCopy()
  {
    mNotifyAutoCopy = true;
  }

  /**
   * MaybeNotifyAccessibleCaretEventHub() starts to notify
   * AccessibleCaretEventHub of selection change if aPresShell has it.
   */
  void MaybeNotifyAccessibleCaretEventHub(nsIPresShell* aPresShell)
  {
    if (!mAccessibleCaretEventHub && aPresShell) {
      mAccessibleCaretEventHub = aPresShell->GetAccessibleCaretEventHub();
    }
  }

  /**
   * StopNotifyingAccessibleCaretEventHub() stops notifying
   * AccessibleCaretEventHub of selection change.
   */
  void StopNotifyingAccessibleCaretEventHub()
  {
    mAccessibleCaretEventHub = nullptr;
  }

  /**
   * EnableSelectionChangeEvent() starts to notify
   * SelectionChangeEventDispatcher of selection change to dispatch a
   * selectionchange event at every selection change.
   */
  void EnableSelectionChangeEvent()
  {
    if (!mSelectionChangeEventDispatcher) {
      mSelectionChangeEventDispatcher = new SelectionChangeEventDispatcher();
    }
  }

  nsIDocument* GetParentObject() const;
  DocGroup* GetDocGroup() const;

  // utility methods for scrolling the selection into view
  nsPresContext* GetPresContext() const;
  nsIPresShell* GetPresShell() const;
  nsFrameSelection* GetFrameSelection() const { return mFrameSelection; }
  // Returns a rect containing the selection region, and frame that that
  // position is relative to. For SELECTION_ANCHOR_REGION or
  // SELECTION_FOCUS_REGION the rect is a zero-width rectangle. For
  // SELECTION_WHOLE_SELECTION the rect contains both the anchor and focus
  // region rects.
  nsIFrame*     GetSelectionAnchorGeometry(SelectionRegion aRegion, nsRect *aRect);
  // Returns the position of the region (SELECTION_ANCHOR_REGION or
  // SELECTION_FOCUS_REGION only), and frame that that position is relative to.
  // The 'position' is a zero-width rectangle.
  nsIFrame*     GetSelectionEndPointGeometry(SelectionRegion aRegion, nsRect *aRect);

  nsresult      PostScrollSelectionIntoViewEvent(
                                        SelectionRegion aRegion,
                                        int32_t aFlags,
                                        nsIPresShell::ScrollAxis aVertical,
                                        nsIPresShell::ScrollAxis aHorizontal);
  enum {
    SCROLL_SYNCHRONOUS = 1<<1,
    SCROLL_FIRST_ANCESTOR_ONLY = 1<<2,
    SCROLL_DO_FLUSH = 1<<3,  // only matters if SCROLL_SYNCHRONOUS is passed too
    SCROLL_OVERFLOW_HIDDEN = 1<<5,
    SCROLL_FOR_CARET_MOVE = 1<<6
  };
  // If aFlags doesn't contain SCROLL_SYNCHRONOUS, then we'll flush when
  // the scroll event fires so we make sure to scroll to the right place.
  // Otherwise, if SCROLL_DO_FLUSH is also in aFlags, then this method will
  // flush layout and you MUST hold a strong ref on 'this' for the duration
  // of this call.  This might destroy arbitrary layout objects.
  nsresult      ScrollIntoView(SelectionRegion aRegion,
                               nsIPresShell::ScrollAxis aVertical =
                                 nsIPresShell::ScrollAxis(),
                               nsIPresShell::ScrollAxis aHorizontal =
                                 nsIPresShell::ScrollAxis(),
                               int32_t aFlags = 0);
  nsresult      SubtractRange(RangeData* aRange, nsRange* aSubtract,
                              nsTArray<RangeData>* aOutput);
  /**
   * AddItem adds aRange to this Selection.  If mUserInitiated is true,
   * then aRange is first scanned for -moz-user-select:none nodes and split up
   * into multiple ranges to exclude those before adding the resulting ranges
   * to this Selection.
   */
  nsresult      AddItem(nsRange* aRange, int32_t* aOutIndex, bool aNoStartSelect = false);
  nsresult      RemoveItem(nsRange* aRange);
  nsresult      RemoveCollapsedRanges();
  nsresult      Clear(nsPresContext* aPresContext);
  nsresult      Collapse(nsINode* aContainer, int32_t aOffset)
  {
    if (!aContainer) {
      return NS_ERROR_INVALID_ARG;
    }
    return Collapse(RawRangeBoundary(aContainer, aOffset));
  }
  nsresult      Collapse(const RawRangeBoundary& aPoint)
  {
    ErrorResult result;
    Collapse(aPoint, result);
    return result.StealNSResult();
  }

  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  nsresult      Extend(nsINode* aContainer, int32_t aOffset);

  nsRange*      GetRangeAt(int32_t aIndex) const;

  // Get the anchor-to-focus range if we don't care which end is
  // anchor and which end is focus.
  const nsRange* GetAnchorFocusRange() const {
    return mAnchorFocusRange;
  }

  nsDirection GetDirection() const
  {
    return mDirection;
  }

  void         SetDirection(nsDirection aDir){mDirection = aDir;}
  nsresult     SetAnchorFocusToRange(nsRange *aRange);
  void         ReplaceAnchorFocusRange(nsRange *aRange);
  void         AdjustAnchorFocusForMultiRange(nsDirection aDirection);

  nsresult GetPrimaryFrameForAnchorNode(nsIFrame** aReturnFrame);
  nsresult GetPrimaryFrameForFocusNode(nsIFrame** aReturnFrame,
                                       int32_t* aOffset, bool aVisual);

  UniquePtr<SelectionDetails> LookUpSelection(
    nsIContent* aContent,
    int32_t aContentOffset,
    int32_t aContentLength,
    UniquePtr<SelectionDetails> aDetailsHead,
    SelectionType aSelectionType,
    bool aSlowCheck);

  NS_IMETHOD   Repaint(nsPresContext* aPresContext);

  // Note: StartAutoScrollTimer might destroy arbitrary frames etc.
  nsresult     StartAutoScrollTimer(nsIFrame* aFrame,
                                    const nsPoint& aPoint,
                                    uint32_t aDelay);

  nsresult     StopAutoScrollTimer();

  JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;

  // WebIDL methods
  nsINode* GetAnchorNode() const
  {
    const RangeBoundary& anchor = AnchorRef();
    return anchor.IsSet() ? anchor.Container() : nullptr;
  }
  uint32_t AnchorOffset() const
  {
    const RangeBoundary& anchor = AnchorRef();
    return anchor.IsSet() ? anchor.Offset() : 0;
  }
  nsINode* GetFocusNode() const
  {
    const RangeBoundary& focus = FocusRef();
    return focus.IsSet() ? focus.Container() : nullptr;
  }
  uint32_t FocusOffset() const
  {
    const RangeBoundary& focus = FocusRef();
    return focus.IsSet() ? focus.Offset() : 0;
  }

  nsIContent* GetChildAtAnchorOffset()
  {
    const RangeBoundary& anchor = AnchorRef();
    return anchor.IsSet() ? anchor.GetChildAtOffset() : nullptr;
  }
  nsIContent* GetChildAtFocusOffset()
  {
    const RangeBoundary& focus = FocusRef();
    return focus.IsSet() ? focus.GetChildAtOffset() : nullptr;
  }

  const RangeBoundary& AnchorRef() const;
  const RangeBoundary& FocusRef() const;

  /*
   * IsCollapsed -- is the whole selection just one point, or unset?
   */
  bool IsCollapsed() const
  {
    uint32_t cnt = mRanges.Length();
    if (cnt == 0) {
      return true;
    }

    if (cnt != 1) {
      return false;
    }

    return mRanges[0].mRange->Collapsed();
  }

  // *JS() methods are mapped to Selection.*().
  // They may move focus only when the range represents normal selection.
  // These methods shouldn't be used by non-JS callers.
  void CollapseJS(nsINode* aContainer, uint32_t aOffset,
                  mozilla::ErrorResult& aRv);
  void CollapseToStartJS(mozilla::ErrorResult& aRv);
  void CollapseToEndJS(mozilla::ErrorResult& aRv);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void ExtendJS(nsINode& aContainer, uint32_t aOffset,
                mozilla::ErrorResult& aRv);

  void SelectAllChildrenJS(nsINode& aNode, mozilla::ErrorResult& aRv);

  /**
   * Deletes this selection from document the nodes belong to.
   */
  void DeleteFromDocument(mozilla::ErrorResult& aRv);

  uint32_t RangeCount() const
  {
    return mRanges.Length();
  }

  void GetType(nsAString& aOutType) const;

  nsRange* GetRangeAt(uint32_t aIndex, mozilla::ErrorResult& aRv);
  void AddRangeJS(nsRange& aRange, mozilla::ErrorResult& aRv);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void RemoveRange(nsRange& aRange, mozilla::ErrorResult& aRv);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY void RemoveAllRanges(mozilla::ErrorResult& aRv);

  /**
   * RemoveAllRangesTemporarily() is useful if the caller will add one or more
   * ranges later.  This tries to cache a removing range if it's possible.
   * If a range is not referred by anything else this selection, the range
   * can be reused later.  Otherwise, this works as same as RemoveAllRanges().
   */
  nsresult RemoveAllRangesTemporarily();

  void Stringify(nsAString& aResult);

  /**
   * Indicates whether the node is part of the selection. If partlyContained
   * is true, the function returns true when some part of the node
   * is part of the selection. If partlyContained is false, the
   * function only returns true when the entire node is part of the selection.
   */
  bool ContainsNode(nsINode& aNode, bool aPartlyContained, mozilla::ErrorResult& aRv);

  /**
   * Check to see if the given point is contained within the selection area. In
   * particular, this iterates through all the rects that make up the selection,
   * not just the bounding box, and checks to see if the given point is contained
   * in any one of them.
   * @param aPoint The point to check, relative to the root frame.
   */
  bool ContainsPoint(const nsPoint& aPoint);

  /**
   * Modifies the selection.  Note that the parameters are case-insensitive.
   *
   * @param alter can be one of { "move", "extend" }
   *   - "move" collapses the selection to the end of the selection and
   *      applies the movement direction/granularity to the collapsed
   *      selection.
   *   - "extend" leaves the start of the selection unchanged, and applies
   *      movement direction/granularity to the end of the selection.
   * @param direction can be one of { "forward", "backward", "left", "right" }
   * @param granularity can be one of { "character", "word",
   *                                    "line", "lineboundary" }
   *
   * @throws NS_ERROR_NOT_IMPLEMENTED if the granularity is "sentence",
   * "sentenceboundary", "paragraph", "paragraphboundary", or
   * "documentboundary".  Throws NS_ERROR_INVALID_ARG if alter, direction,
   * or granularity has an unrecognized value.
   */
  void Modify(const nsAString& aAlter, const nsAString& aDirection,
              const nsAString& aGranularity, mozilla::ErrorResult& aRv);

  void SetBaseAndExtentJS(nsINode& aAnchorNode, uint32_t aAnchorOffset,
                          nsINode& aFocusNode, uint32_t aFocusOffset,
                          mozilla::ErrorResult& aRv);

  bool GetInterlinePosition(mozilla::ErrorResult& aRv);
  void SetInterlinePosition(bool aValue, mozilla::ErrorResult& aRv);

  Nullable<int16_t> GetCaretBidiLevel(mozilla::ErrorResult& aRv) const;
  void SetCaretBidiLevel(const Nullable<int16_t>& aCaretBidiLevel, mozilla::ErrorResult& aRv);

  void ToStringWithFormat(const nsAString& aFormatType,
                          uint32_t aFlags,
                          int32_t aWrapColumn,
                          nsAString& aReturn,
                          mozilla::ErrorResult& aRv);
  void AddSelectionListener(nsISelectionListener* aListener);
  void RemoveSelectionListener(nsISelectionListener* aListener);

  RawSelectionType RawType() const
  {
    return ToRawSelectionType(mSelectionType);
  }
  SelectionType Type() const { return mSelectionType; }

  void GetRangesForInterval(nsINode& aBeginNode, int32_t aBeginOffset,
                            nsINode& aEndNode, int32_t aEndOffset,
                            bool aAllowAdjacent,
                            nsTArray<RefPtr<nsRange>>& aReturn,
                            mozilla::ErrorResult& aRv);

  void ScrollIntoView(int16_t aRegion, bool aIsSynchronous,
                      int16_t aVPercent, int16_t aHPercent,
                      mozilla::ErrorResult& aRv);

  void SetColors(const nsAString& aForeColor, const nsAString& aBackColor,
                 const nsAString& aAltForeColor, const nsAString& aAltBackColor,
                 mozilla::ErrorResult& aRv);

  void ResetColors(mozilla::ErrorResult& aRv);

  /**
   * Non-JS callers should use the following
   * collapse/collapseToStart/extend/etc methods, instead of the *JS
   * versions that bindings call.
   */

  /**
   * Collapses the selection to a single point, at the specified offset
   * in the given node. When the selection is collapsed, and the content
   * is focused and editable, the caret will blink there.
   * @param aContainer The given node where the selection will be set
   * @param offset      Where in given dom node to place the selection (the offset into the given node)
   */
  void Collapse(nsINode& aContainer, uint32_t aOffset, ErrorResult& aRv)
  {
    Collapse(RawRangeBoundary(&aContainer, aOffset), aRv);
  }

  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void Collapse(const RawRangeBoundary& aPoint, ErrorResult& aRv);

  /**
   * Collapses the whole selection to a single point at the start
   * of the current selection (irrespective of direction).  If content
   * is focused and editable, the caret will blink there.
   */
  void CollapseToStart(mozilla::ErrorResult& aRv);

  /**
   * Collapses the whole selection to a single point at the end
   * of the current selection (irrespective of direction).  If content
   * is focused and editable, the caret will blink there.
   */
  void CollapseToEnd(mozilla::ErrorResult& aRv);

  /**
   * Extends the selection by moving the selection end to the specified node and
   * offset, preserving the selection begin position. The new selection end
   * result will always be from the anchorNode to the new focusNode, regardless
   * of direction.
   *
   * @param aContainer The node where the selection will be extended to
   * @param aOffset    Where in aContainer to place the offset of the new selection end.
   */
  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void Extend(nsINode& aContainer, uint32_t aOffset, ErrorResult& aRv);

  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void AddRange(nsRange& aRange, mozilla::ErrorResult& aRv);

  /**
   * Adds all children of the specified node to the selection.
   * @param aNode the parent of the children to be added to the selection.
   */
  MOZ_CAN_RUN_SCRIPT_BOUNDARY
  void SelectAllChildren(nsINode& aNode, mozilla::ErrorResult& aRv);

  void SetBaseAndExtent(nsINode& aAnchorNode, uint32_t aAnchorOffset,
                        nsINode& aFocusNode, uint32_t aFocusOffset,
                        mozilla::ErrorResult& aRv);

  void AddSelectionChangeBlocker();
  void RemoveSelectionChangeBlocker();
  bool IsBlockingSelectionChangeEvents() const;

  // Whether this selection is focused in an editable element.
  bool IsEditorSelection() const;

  /**
   * Set the painting style for the range. The range must be a range in
   * the selection. The textRangeStyle will be used by text frame
   * when it is painting the selection.
   */
  nsresult SetTextRangeStyle(nsRange* aRange,
                             const TextRangeStyle& aTextRangeStyle);

  // Methods to manipulate our mFrameSelection's ancestor limiter.
  nsIContent* GetAncestorLimiter() const;
  void SetAncestorLimiter(nsIContent* aLimiter);

  /*
   * Frame Offset cache can be used just during calling nsEditor::EndPlaceHolderTransaction.
   * EndPlaceHolderTransaction will give rise to reflow/refreshing view/scroll, and call times
   * of nsTextFrame::GetPointFromOffset whose return value is to be cached.
   * see bugs 35296 and 199412
   */
  void SetCanCacheFrameOffset(bool aCanCacheFrameOffset);

  // Selection::GetRangesForIntervalArray
  //
  //    Fills a nsTArray with the ranges overlapping the range specified by
  //    the given endpoints. Ranges in the selection exactly adjacent to the
  //    input range are not returned unless aAllowAdjacent is set.
  //
  //    For example, if the following ranges were in the selection
  //    (assume everything is within the same node)
  //
  //    Start Offset: 0 2 7 9
  //      End Offset: 2 5 9 10
  //
  //    and passed aBeginOffset of 2 and aEndOffset of 9, then with
  //    aAllowAdjacent set, all the ranges should be returned. If
  //    aAllowAdjacent was false, the ranges [2, 5] and [7, 9] only
  //    should be returned
  //
  //    Now that overlapping ranges are disallowed, there can be a maximum of
  //    2 adjacent ranges
  nsresult
  GetRangesForIntervalArray(nsINode* aBeginNode, int32_t aBeginOffset,
                            nsINode* aEndNode, int32_t aEndOffset,
                            bool aAllowAdjacent,
                            nsTArray<nsRange*>* aRanges);

  /**
   * Modifies the cursor Bidi level after a change in keyboard direction
   * @param langRTL is true if the new language is right-to-left or
   *                false if the new language is left-to-right.
   */
  nsresult SelectionLanguageChange(bool aLangRTL);

private:
  friend class ::nsAutoScrollTimer;

  // Note: DoAutoScroll might destroy arbitrary frames etc.
  nsresult DoAutoScroll(nsIFrame* aFrame, nsPoint aPoint);

  // We are not allowed to be in nodes whose root is not our document
  bool HasSameRoot(nsINode& aNode);

  // XXX Please don't add additional uses of this method, it's only for
  // XXX supporting broken code (bug 1245883) in the following classes:
  friend class ::nsCopySupport;
  friend class ::nsHTMLCopyEncoder;
  MOZ_CAN_RUN_SCRIPT
  void AddRangeInternal(nsRange& aRange, nsIDocument* aDocument, ErrorResult&);

  // This is helper method for GetPrimaryFrameForFocusNode.
  // If aVisual is true, this returns caret frame.
  // If false, this returns primary frame.
  nsresult GetPrimaryOrCaretFrameForNodeOffset(nsIContent* aContent,
                                               uint32_t aOffset,
                                               nsIFrame** aReturnFrame,
                                               int32_t* aOffsetUsed,
                                               bool aVisual) const;

  // Get the cached value for nsTextFrame::GetPointFromOffset.
  nsresult GetCachedFrameOffset(nsIFrame* aFrame, int32_t inOffset,
                                nsPoint& aPoint);

public:
  SelectionType GetType() const { return mSelectionType; }
  void SetType(SelectionType aSelectionType)
  {
    mSelectionType = aSelectionType;
  }

  SelectionCustomColors* GetCustomColors() const { return mCustomColors.get(); }

  MOZ_CAN_RUN_SCRIPT nsresult NotifySelectionListeners(bool aCalledByJS);
  MOZ_CAN_RUN_SCRIPT nsresult NotifySelectionListeners();

  friend struct AutoUserInitiated;
  struct MOZ_RAII AutoUserInitiated
  {
    explicit AutoUserInitiated(Selection* aSelection
                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
      : mSavedValue(aSelection->mUserInitiated)
    {
      MOZ_GUARD_OBJECT_NOTIFIER_INIT;
      aSelection->mUserInitiated = true;
    }
    AutoRestore<bool> mSavedValue;
    MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
  };

private:
  friend struct mozilla::AutoPrepareFocusRange;
  class ScrollSelectionIntoViewEvent;
  friend class ScrollSelectionIntoViewEvent;

  class ScrollSelectionIntoViewEvent : public Runnable {
  public:
    NS_DECL_NSIRUNNABLE
    ScrollSelectionIntoViewEvent(Selection* aSelection,
                                 SelectionRegion aRegion,
                                 nsIPresShell::ScrollAxis aVertical,
                                 nsIPresShell::ScrollAxis aHorizontal,
                                 int32_t aFlags)
      : Runnable("dom::Selection::ScrollSelectionIntoViewEvent")
      , mSelection(aSelection)
      , mRegion(aRegion)
      , mVerticalScroll(aVertical)
      , mHorizontalScroll(aHorizontal)
      , mFlags(aFlags)
    {
      NS_ASSERTION(aSelection, "null parameter");
    }
    void Revoke() { mSelection = nullptr; }
  private:
    Selection *mSelection;
    SelectionRegion mRegion;
    nsIPresShell::ScrollAxis mVerticalScroll;
    nsIPresShell::ScrollAxis mHorizontalScroll;
    int32_t mFlags;
  };

  /**
   * Set mAnchorFocusRange to mRanges[aIndex] if aIndex is a valid index.
   * Set mAnchorFocusRange to nullptr if aIndex is negative.
   * Otherwise, i.e., if aIndex is positive but out of bounds of mRanges, do
   * nothing.
   */
  void SetAnchorFocusRange(int32_t aIndex);
  void SelectFramesForContent(nsIContent* aContent, bool aSelected);
  nsresult SelectAllFramesForContent(nsIContentIterator* aInnerIter,
                                     nsIContent *aContent,
                                     bool aSelected);
  nsresult SelectFrames(nsPresContext* aPresContext,
                        nsRange* aRange,
                        bool aSelect);

  /**
   * Test whether the supplied range points to a single table element.
   * Result is one of the TableSelection constants. "None" means
   * a table element isn't selected.
   */
  nsresult GetTableSelectionType(nsRange* aRange,
                                 TableSelection* aTableSelectionType);
  nsresult GetTableCellLocationFromRange(nsRange* aRange,
                                         TableSelection* aSelectionType,
                                         int32_t* aRow,
                                         int32_t* aCol);
  nsresult AddTableCellRange(nsRange* aRange,
                             bool* aDidAddRange,
                             int32_t* aOutIndex);

  nsresult FindInsertionPoint(
      nsTArray<RangeData>* aElementArray,
      nsINode* aPointNode, int32_t aPointOffset,
      nsresult (*aComparator)(nsINode*,int32_t,nsRange*,int32_t*),
      int32_t* aPoint);
  bool EqualsRangeAtPoint(nsINode* aBeginNode, int32_t aBeginOffset,
                            nsINode* aEndNode, int32_t aEndOffset,
                            int32_t aRangeIndex);
  nsresult GetIndicesForInterval(nsINode* aBeginNode, int32_t aBeginOffset,
                                 nsINode* aEndNode, int32_t aEndOffset,
                                 bool aAllowAdjacent,
                                 int32_t* aStartIndex, int32_t* aEndIndex);
  RangeData* FindRangeData(nsRange* aRange);

  void UserSelectRangesToAdd(nsRange* aItem, nsTArray<RefPtr<nsRange> >& rangesToAdd);

  /**
   * Helper method for AddItem.
   */
  nsresult AddItemInternal(nsRange* aRange, int32_t* aOutIndex);

  nsIDocument* GetDocument() const;
  nsPIDOMWindowOuter* GetWindow() const;
  HTMLEditor* GetHTMLEditor() const;

  /**
   * GetCommonEditingHostForAllRanges() returns common editing host of all
   * ranges if there is. If at least one of the ranges is in non-editable
   * element, returns nullptr.  See following examples for the detail:
   *
   *  <div id="a" contenteditable>
   *    an[cestor
   *    <div id="b" contenteditable="false">
   *      non-editable
   *      <div id="c" contenteditable>
   *        desc]endant
   *  in this case, this returns div#a because div#c is also in div#a.
   *
   *  <div id="a" contenteditable>
   *    an[ce]stor
   *    <div id="b" contenteditable="false">
   *      non-editable
   *      <div id="c" contenteditable>
   *        de[sc]endant
   *  in this case, this returns div#a because second range is also in div#a
   *  and common ancestor of the range (i.e., div#c) is editable.
   *
   *  <div id="a" contenteditable>
   *    an[ce]stor
   *    <div id="b" contenteditable="false">
   *      [non]-editable
   *      <div id="c" contenteditable>
   *        de[sc]endant
   *  in this case, this returns nullptr because the second range is in
   *  non-editable area.
   */
  Element* GetCommonEditingHostForAllRanges();

  // These are the ranges inside this selection. They are kept sorted in order
  // of DOM start position.
  //
  // This data structure is sorted by the range beginnings. As the ranges are
  // disjoint, it is also implicitly sorted by the range endings. This allows
  // us to perform binary searches when searching for existence of a range,
  // giving us O(log n) search time.
  //
  // Inserting a new range requires finding the overlapping interval, requiring
  // two binary searches plus up to an additional 6 DOM comparisons. If this
  // proves to be a performance concern, then an interval tree may be a
  // possible solution, allowing the calculation of the overlap interval in
  // O(log n) time, though this would require rebalancing and other overhead.
  AutoTArray<RangeData, 1> mRanges;

  RefPtr<nsRange> mAnchorFocusRange;
  // mCachedRange is set by RemoveAllRangesTemporarily() and used by
  // Collapse() and SetBaseAndExtent().  If there is a range which will be
  // released by Clear(), RemoveAllRangesTemporarily() stores it with this.
  // If Collapse() is called without existing ranges, it'll reuse this range
  // for saving the creation cost.
  // Note that while the range is cached by this, we keep the range being
  // a mutation observer because it is not so cheap to register the range
  // as a mutation observer again.  On the other hand, we make it not
  // positioned because it is not so cheap to keep valid DOM point against
  // mutations.  This does not cause any problems because we will set new
  // DOM point when we treat it as a range of Selection again.
  RefPtr<nsRange> mCachedRange;
  RefPtr<nsFrameSelection> mFrameSelection;
  RefPtr<AccessibleCaretEventHub> mAccessibleCaretEventHub;
  RefPtr<SelectionChangeEventDispatcher> mSelectionChangeEventDispatcher;
  RefPtr<nsAutoScrollTimer> mAutoScrollTimer;
  nsTArray<nsCOMPtr<nsISelectionListener>> mSelectionListeners;
  nsRevocableEventPtr<ScrollSelectionIntoViewEvent> mScrollEvent;
  CachedOffsetForFrame* mCachedOffsetForFrame;
  nsDirection mDirection;
  SelectionType mSelectionType;
  UniquePtr<SelectionCustomColors> mCustomColors;

  // Non-zero if we don't want any changes we make to the selection to be
  // visible to content. If non-zero, content won't be notified about changes.
  uint32_t mSelectionChangeBlockerCount;

  /**
   * True if the current selection operation was initiated by user action.
   * It determines whether we exclude -moz-user-select:none nodes or not,
   * as well as whether selectstart events will be fired.
   */
  bool mUserInitiated;

  /**
   * When the selection change is caused by a call of Selection API,
   * mCalledByJS is true.  Otherwise, false.
   */
  bool mCalledByJS;

  /**
   * true if AutoCopyListner::OnSelectionChange() should be called.
   */
  bool mNotifyAutoCopy;
};

// Stack-class to turn on/off selection batching.
class MOZ_STACK_CLASS SelectionBatcher final
{
private:
  RefPtr<Selection> mSelection;
public:
  explicit SelectionBatcher(Selection* aSelection)
  {
    mSelection = aSelection;
    if (mSelection) {
      mSelection->StartBatchChanges();
    }
  }

  ~SelectionBatcher()
  {
    if (mSelection) {
      mSelection->EndBatchChanges();
    }
  }
};

class MOZ_RAII AutoHideSelectionChanges final
{
private:
  RefPtr<Selection> mSelection;
  MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
public:
  explicit AutoHideSelectionChanges(const nsFrameSelection* aFrame);

  explicit AutoHideSelectionChanges(Selection* aSelection
                                    MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
    : mSelection(aSelection)
  {
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
    mSelection = aSelection;
    if (mSelection) {
      mSelection->AddSelectionChangeBlocker();
    }
  }

  ~AutoHideSelectionChanges()
  {
    if (mSelection) {
      mSelection->RemoveSelectionChangeBlocker();
    }
  }
};

} // namespace dom

inline bool
IsValidRawSelectionType(RawSelectionType aRawSelectionType)
{
  return aRawSelectionType >= nsISelectionController::SELECTION_NONE &&
         aRawSelectionType <= nsISelectionController::SELECTION_URLSTRIKEOUT;
}

inline SelectionType
ToSelectionType(RawSelectionType aRawSelectionType)
{
  if (!IsValidRawSelectionType(aRawSelectionType)) {
    return SelectionType::eInvalid;
  }
  return static_cast<SelectionType>(aRawSelectionType);
}

inline RawSelectionType
ToRawSelectionType(SelectionType aSelectionType)
{
  MOZ_ASSERT(aSelectionType != SelectionType::eInvalid);
  return static_cast<RawSelectionType>(aSelectionType);
}

inline RawSelectionType
ToRawSelectionType(TextRangeType aTextRangeType)
{
  return ToRawSelectionType(ToSelectionType(aTextRangeType));
}

inline SelectionTypeMask
ToSelectionTypeMask(SelectionType aSelectionType)
{
  MOZ_ASSERT(aSelectionType != SelectionType::eInvalid);
  return aSelectionType == SelectionType::eNone ? 0 :
           (1 << (static_cast<uint8_t>(aSelectionType) - 1));
}

} // namespace mozilla

#endif // mozilla_Selection_h__