gecko-dev/editor/libeditor/WSRunObject.h

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/* -*- 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 WSRunObject_h
#define WSRunObject_h
#include "mozilla/dom/Text.h"
#include "mozilla/EditorBase.h"
#include "mozilla/EditorDOMPoint.h" // for EditorDOMPoint
namespace mozilla {
class HTMLEditor;
class HTMLEditRules;
// class WSRunObject represents the entire whitespace situation
// around a given point. It collects up a list of nodes that contain
// whitespace and categorizes in up to 3 different WSFragments (detailed
// below). Each WSFragment is a collection of whitespace that is
// either all insignificant, or that is significant. A WSFragment could
// consist of insignificant whitespace because it is after a block
// boundary or after a break. Or it could be insignificant because it
// is before a block. Or it could be significant because it is
// surrounded by text, or starts and ends with nbsps, etc.
// Throughout I refer to LeadingWS, NormalWS, TrailingWS. LeadingWS & TrailingWS
// are runs of ascii ws that are insignificant (do not render) because they
// are adjacent to block boundaries, or after a break. NormalWS is ws that
// does cause soem rendering. Note that not all the ws in a NormalWS run need
// render. For example, two ascii spaces surrounded by text on both sides
// will only render as one space (in non-preformatted stlye html), yet both
// spaces count as NormalWS. Together, they render as the one visible space.
/**
* A type-safe bitfield indicating various types of whitespace or other things.
* Used as a member variable in WSRunObject and WSFragment.
*
* XXX: If this idea is useful in other places, we should generalize it using a
* template.
*/
class WSType
{
public:
enum Enum
{
none = 0,
leadingWS = 1, // leading insignificant ws, ie, after block or br
trailingWS = 1 << 1, // trailing insignificant ws, ie, before block
normalWS = 1 << 2, // normal significant ws, ie, after text, image, ...
text = 1 << 3, // indicates regular (non-ws) text
special = 1 << 4, // indicates an inline non-container, like image
br = 1 << 5, // indicates a br node
otherBlock = 1 << 6, // indicates a block other than one ws run is in
thisBlock = 1 << 7, // indicates the block ws run is in
block = otherBlock | thisBlock // block found
};
/**
* Implicit constructor, because the enums are logically just WSTypes
* themselves, and are only a separate type because there's no other obvious
* way to name specific WSType values.
*/
MOZ_IMPLICIT WSType(const Enum& aEnum = none)
: mEnum(aEnum)
{}
// operator==, &, and | need to access mEnum
friend bool operator==(const WSType& aLeft, const WSType& aRight);
friend const WSType operator&(const WSType& aLeft, const WSType& aRight);
friend const WSType operator|(const WSType& aLeft, const WSType& aRight);
WSType& operator=(const WSType& aOther)
{
// This handles self-assignment fine
mEnum = aOther.mEnum;
return *this;
}
WSType& operator&=(const WSType& aOther)
{
mEnum &= aOther.mEnum;
return *this;
}
WSType& operator|=(const WSType& aOther)
{
mEnum |= aOther.mEnum;
return *this;
}
private:
uint16_t mEnum;
void bool_conversion_helper() {}
public:
// Allow boolean conversion with no numeric conversion
typedef void (WSType::*bool_type)();
operator bool_type() const
{
return mEnum ? &WSType::bool_conversion_helper : nullptr;
}
};
/**
* These are declared as global functions so "WSType::Enum == WSType" et al.
* will work using the implicit constructor.
*/
inline bool operator==(const WSType& aLeft, const WSType& aRight)
{
return aLeft.mEnum == aRight.mEnum;
}
inline bool operator!=(const WSType& aLeft, const WSType& aRight)
{
return !(aLeft == aRight);
}
inline const WSType operator&(const WSType& aLeft, const WSType& aRight)
{
WSType ret;
ret.mEnum = aLeft.mEnum & aRight.mEnum;
return ret;
}
inline const WSType operator|(const WSType& aLeft, const WSType& aRight)
{
WSType ret;
ret.mEnum = aLeft.mEnum | aRight.mEnum;
return ret;
}
/**
* Make sure that & and | of WSType::Enum creates a WSType instead of an int,
* because operators between WSType and int shouldn't work
*/
inline const WSType operator&(const WSType::Enum& aLeft,
const WSType::Enum& aRight)
{
return WSType(aLeft) & WSType(aRight);
}
inline const WSType operator|(const WSType::Enum& aLeft,
const WSType::Enum& aRight)
{
return WSType(aLeft) | WSType(aRight);
}
class MOZ_STACK_CLASS WSRunObject final
{
protected:
typedef EditorBase::AutoTransactionsConserveSelection
AutoTransactionsConserveSelection;
public:
enum BlockBoundary
{
kBeforeBlock,
kBlockStart,
kBlockEnd,
kAfterBlock
};
enum {eBefore = 1};
enum {eAfter = 1 << 1};
enum {eBoth = eBefore | eAfter};
template<typename PT, typename CT>
WSRunObject(HTMLEditor* aHTMLEditor,
const EditorDOMPointBase<PT, CT>& aPoint);
WSRunObject(HTMLEditor* aHTMLEditor, nsINode* aNode, int32_t aOffset);
~WSRunObject();
// ScrubBlockBoundary removes any non-visible whitespace at the specified
// location relative to a block node.
static nsresult ScrubBlockBoundary(HTMLEditor* aHTMLEditor,
BlockBoundary aBoundary,
nsINode* aBlock,
int32_t aOffset = -1);
// PrepareToJoinBlocks fixes up ws at the end of aLeftBlock and the
// beginning of aRightBlock in preperation for them to be joined. Example
// of fixup: trailingws in aLeftBlock needs to be removed.
static nsresult PrepareToJoinBlocks(HTMLEditor* aHTMLEditor,
dom::Element* aLeftBlock,
dom::Element* aRightBlock);
// PrepareToDeleteRange fixes up ws before {aStartNode,aStartOffset}
// and after {aEndNode,aEndOffset} in preperation for content
// in that range to be deleted. Note that the nodes and offsets
// are adjusted in response to any dom changes we make while
// adjusting ws.
// example of fixup: trailingws before {aStartNode,aStartOffset}
// needs to be removed.
static nsresult PrepareToDeleteRange(HTMLEditor* aHTMLEditor,
nsCOMPtr<nsINode>* aStartNode,
int32_t* aStartOffset,
nsCOMPtr<nsINode>* aEndNode,
int32_t* aEndOffset);
// PrepareToDeleteNode fixes up ws before and after aContent in preparation
// for aContent to be deleted. Example of fixup: trailingws before
// aContent needs to be removed.
static nsresult PrepareToDeleteNode(HTMLEditor* aHTMLEditor,
nsIContent* aContent);
// PrepareToSplitAcrossBlocks fixes up ws before and after
// {aSplitNode,aSplitOffset} in preparation for a block parent to be split.
// Note that the aSplitNode and aSplitOffset are adjusted in response to
// any DOM changes we make while adjusting ws. Example of fixup: normalws
// before {aSplitNode,aSplitOffset} needs to end with nbsp.
static nsresult PrepareToSplitAcrossBlocks(HTMLEditor* aHTMLEditor,
nsCOMPtr<nsINode>* aSplitNode,
int32_t* aSplitOffset);
/**
* InsertBreak() inserts a <br> node at (before) aPointToInsert and delete
* unnecessary whitespaces around there and/or replaces whitespaces with
* non-breaking spaces. Note that if the point is in a text node, the
* text node will be split and insert new <br> node between the left node
* and the right node.
*
* @param aSelection The selection for the editor.
* @param aPointToInsert The point to insert new <br> element. Note that
* it'll be inserted before this point. I.e., the
* point will be the point of new <br>.
* @param aSelect If eNone, this won't change selection.
* If eNext, selection will be collapsed after the
* <br> element.
* If ePrevious, selection will be collapsed at the
* <br> element.
* @return The new <br> node. If failed to create new <br>
* node, returns nullptr.
*/
template<typename PT, typename CT>
already_AddRefed<dom::Element>
InsertBreak(Selection& aSelection,
const EditorDOMPointBase<PT, CT>& aPointToInsert,
nsIEditor::EDirection aSelect);
/**
* InsertText() inserts aStringToInsert to aPointToInsert and makes any
* needed adjustments to white spaces around that point. E.g., trailing white
* spaces before aPointToInsert needs to be removed.
* This calls EditorBase::InsertTextWithTransaction() after adjusting white
* spaces. So, please refer the method's explanation to know what this
* method exactly does.
*
* @param aDocument The document of this editor.
* @param aStringToInsert The string to insert.
* @param aPointToInser The point to insert aStringToInsert.
* Must be valid DOM point.
* @param aPointAfterInsertedString
* The point after inserted aStringToInsert.
* So, when this method actually inserts string,
* this is set to a point in the text node.
* Otherwise, this may be set to aPointToInsert.
* @return When this succeeds to insert the string or
* does nothing during composition, returns NS_OK.
* Otherwise, an error code.
*/
template<typename PT, typename CT>
nsresult InsertText(nsIDocument& aDocument,
const nsAString& aStringToInsert,
const EditorDOMPointBase<PT, CT>& aPointToInsert,
EditorRawDOMPoint* aPointAfterInsertedString = nullptr);
// DeleteWSBackward deletes a single visible piece of ws before the ws
// point (the point to create the wsRunObject, passed to its constructor).
// It makes any needed conversion to adjacent ws to retain its
// significance.
nsresult DeleteWSBackward();
// DeleteWSForward deletes a single visible piece of ws after the ws point
// (the point to create the wsRunObject, passed to its constructor). It
// makes any needed conversion to adjacent ws to retain its significance.
nsresult DeleteWSForward();
// PriorVisibleNode() returns the first piece of visible thing before aPoint.
// If there is no visible ws qualifying it returns what is before the ws run.
// If outVisNode and/or outvisOffset is unused, callers can use nullptr.
// Note that {outVisNode,outVisOffset} is set to just AFTER the visible
// object. Also outVisOffset might be invalid offset unless outVisNode is
// start reason node.
template<typename PT, typename CT>
void PriorVisibleNode(const EditorDOMPointBase<PT, CT>& aPoint,
nsCOMPtr<nsINode>* outVisNode,
int32_t* outVisOffset,
WSType* outType) const;
template<typename PT, typename CT>
void PriorVisibleNode(const EditorDOMPointBase<PT, CT>& aPoint,
WSType* outType) const
{
PriorVisibleNode(aPoint, nullptr, nullptr, outType);
}
// NextVisibleNode() returns the first piece of visible thing after aPoint.
// If there is no visible ws qualifying it returns what is after the ws run.
// If outVisNode and/or outvisOffset is unused, callers can use nullptr.
// Note that {outVisNode,outVisOffset} is set to just BEFORE the visible
// object. Also outVisOffset might be invalid offset unless outVisNode is
// end reason node.
template<typename PT, typename CT>
void NextVisibleNode(const EditorDOMPointBase<PT, CT>& aPoint,
nsCOMPtr<nsINode>* outVisNode,
int32_t* outVisOffset,
WSType* outType) const;
template<typename PT, typename CT>
void NextVisibleNode(const EditorDOMPointBase<PT, CT>& aPoint,
WSType* outType) const
{
NextVisibleNode(aPoint, nullptr, nullptr, outType);
}
// AdjustWhitespace examines the ws object for nbsp's that can
// be safely converted to regular ascii space and converts them.
nsresult AdjustWhitespace();
protected:
// WSFragment represents a single run of ws (all leadingws, or all normalws,
// or all trailingws, or all leading+trailingws). Note that this single run
// may still span multiple nodes.
struct WSFragment final
{
nsCOMPtr<nsINode> mStartNode; // node where ws run starts
nsCOMPtr<nsINode> mEndNode; // node where ws run ends
int32_t mStartOffset; // offset where ws run starts
int32_t mEndOffset; // offset where ws run ends
// type of ws, and what is to left and right of it
WSType mType, mLeftType, mRightType;
// other ws runs to left or right. may be null.
WSFragment *mLeft, *mRight;
WSFragment()
: mStartOffset(0)
, mEndOffset(0)
, mLeft(nullptr)
, mRight(nullptr)
{}
EditorRawDOMPoint StartPoint() const
{
return EditorRawDOMPoint(mStartNode, mStartOffset);
}
EditorRawDOMPoint EndPoint() const
{
return EditorRawDOMPoint(mEndNode, mEndOffset);
}
};
// A WSPoint struct represents a unique location within the ws run. It is
// always within a textnode that is one of the nodes stored in the list
// in the wsRunObject. For convenience, the character at that point is also
// stored in the struct.
struct MOZ_STACK_CLASS WSPoint final
{
RefPtr<dom::Text> mTextNode;
uint32_t mOffset;
char16_t mChar;
WSPoint()
: mTextNode(nullptr)
, mOffset(0)
, mChar(0)
{}
WSPoint(dom::Text* aTextNode, int32_t aOffset, char16_t aChar)
: mTextNode(aTextNode)
, mOffset(aOffset)
, mChar(aChar)
{}
};
/**
* Return the node which we will handle white-space under. This is the
* closest block within the DOM subtree we're editing, or if none is
* found, the (inline) root of the editable subtree.
*/
nsINode* GetWSBoundingParent();
nsresult GetWSNodes();
void GetRuns();
void ClearRuns();
void MakeSingleWSRun(WSType aType);
nsIContent* GetPreviousWSNodeInner(nsINode* aStartNode,
nsINode* aBlockParent);
nsIContent* GetPreviousWSNode(const EditorDOMPoint& aPoint,
nsINode* aBlockParent);
nsIContent* GetNextWSNodeInner(nsINode* aStartNode, nsINode* aBlockParent);
nsIContent* GetNextWSNode(const EditorDOMPoint& aPoint,
nsINode* aBlockParent);
nsresult PrepareToDeleteRangePriv(WSRunObject* aEndObject);
nsresult PrepareToSplitAcrossBlocksPriv();
/**
* DeleteRange() removes the range between aStartPoint and aEndPoint.
* When aStartPoint and aEndPoint are same point, does nothing.
* When aStartPoint and aEndPoint are in same text node, removes characters
* between them.
* When aStartPoint is in a text node, removes the text data after the point.
* When aEndPoint is in a text node, removes the text data before the point.
* Removes any nodes between them.
*/
template<typename PT1, typename CT1, typename PT2, typename CT2>
nsresult DeleteRange(const EditorDOMPointBase<PT1, CT1>& aStartPoint,
const EditorDOMPointBase<PT2, CT2>& aEndPoint);
/**
* GetNextCharPoint() returns next character's point of aPoint. If there is
* no character after aPoint, mTextNode is set to nullptr.
*/
template<typename PT, typename CT>
WSPoint GetNextCharPoint(const EditorDOMPointBase<PT, CT>& aPoint) const;
WSPoint GetNextCharPoint(const WSPoint& aPoint) const;
/**
* GetPreviousCharPoint() returns previous character's point of of aPoint.
* If there is no character before aPoint, mTextNode is set to nullptr.
*/
template<typename PT, typename CT>
WSPoint GetPreviousCharPoint(const EditorDOMPointBase<PT, CT>& aPoint) const;
WSPoint GetPreviousCharPoint(const WSPoint& aPoint) const;
/**
* GetNextCharPointInternal() and GetPreviousCharPointInternal() are
* helper methods of GetNextCharPoint(const EditorRawDOMPoint&) and
* GetPreviousCharPoint(const EditorRawDOMPoint&). When the container
* isn't in mNodeArray, they call one of these methods. Then, these
* methods look for nearest text node in mNodeArray from aPoint.
* Then, will call GetNextCharPoint(const WSPoint&) or
* GetPreviousCharPoint(const WSPoint&) and returns its result.
*/
template<typename PT, typename CT>
WSPoint
GetNextCharPointInternal(const EditorDOMPointBase<PT, CT>& aPoint) const;
template<typename PT, typename CT>
WSPoint
GetPreviousCharPointInternal(const EditorDOMPointBase<PT, CT>& aPoint) const;
/**
* InsertNBSPAndRemoveFollowingASCIIWhitespaces() inserts an NBSP first.
* Then, if following characters are ASCII whitespaces, will remove them.
*/
nsresult InsertNBSPAndRemoveFollowingASCIIWhitespaces(WSPoint aPoint);
/**
* GetASCIIWhitespacesBounds() retrieves whitespaces before and/or after the
* point specified by aNode and aOffset.
*
* @param aDir Specify eBefore if you want to scan text backward.
* Specify eAfter if you want to scan text forward.
* Specify eBoth if you want to scan text to both
* direction.
* @param aNode The container node where you want to start to scan
* whitespaces from.
* @param aOffset The offset in aNode where you want to start to scan
* whitespaces from.
* @param outStartNode [out] The container of first ASCII whitespace.
* If there is no whitespaces, returns nullptr.
* @param outStartOffset [out] The offset of first ASCII whitespace in
* outStartNode.
* @param outEndNode [out] The container of last ASCII whitespace.
* If there is no whitespaces, returns nullptr.
* @param outEndOffset [out] The offset of last ASCII whitespace in
* outEndNode.
*/
void GetASCIIWhitespacesBounds(int16_t aDir,
nsINode* aNode,
int32_t aOffset,
dom::Text** outStartNode,
int32_t* outStartOffset,
dom::Text** outEndNode,
int32_t* outEndOffset);
/**
* FindNearestRun() looks for a WSFragment which is closest to specified
* direction from aPoint.
*
* @param aPoint The point to start to look for.
* @param aForward true if caller needs to look for a WSFragment after the
* point in the DOM tree. Otherwise, i.e., before the
* point, false.
* @return Found WSFragment instance.
* If aForward is true and:
* if aPoint is end of a run, returns next run.
* if aPoint is start of a run, returns the run.
* if aPoint is before the first run, returns the first
* run.
* If aPoint is after the last run, returns nullptr.
* If aForward is false and:
* if aPoint is end of a run, returns the run.
* if aPoint is start of a run, returns its next run.
* if aPoint is before the first run, returns nullptr.
* if aPoint is after the last run, returns the last run.
*/
template<typename PT, typename CT>
WSFragment* FindNearestRun(const EditorDOMPointBase<PT, CT>& aPoint,
bool aForward) const;
char16_t GetCharAt(dom::Text* aTextNode, int32_t aOffset) const;
nsresult CheckTrailingNBSPOfRun(WSFragment *aRun);
/**
* ReplacePreviousNBSPIfUnncessary() replaces previous character of aPoint
* if it's a NBSP and it's unnecessary.
*
* @param aRun Current text run. aPoint must be in this run.
* @param aPoint Current insertion point. Its previous character is
* unnecessary NBSP will be checked.
*/
template<typename PT, typename CT>
nsresult
ReplacePreviousNBSPIfUnncessary(WSFragment* aRun,
const EditorDOMPointBase<PT, CT>& aPoint);
nsresult CheckLeadingNBSP(WSFragment* aRun, nsINode* aNode,
int32_t aOffset);
nsresult Scrub();
bool IsBlockNode(nsINode* aNode);
EditorRawDOMPoint Point() const
{
return EditorRawDOMPoint(mNode, mOffset);
}
EditorRawDOMPoint StartPoint() const
{
return EditorRawDOMPoint(mStartNode, mStartOffset);
}
EditorRawDOMPoint EndPoint() const
{
return EditorRawDOMPoint(mEndNode, mEndOffset);
}
// The node passed to our constructor.
nsCOMPtr<nsINode> mNode;
// The offset passed to our contructor.
int32_t mOffset;
// Together, the above represent the point at which we are building up ws info.
// true if we are in preformatted whitespace context.
bool mPRE;
// Node/offset where ws starts.
nsCOMPtr<nsINode> mStartNode;
int32_t mStartOffset;
// Reason why ws starts (eText, eOtherBlock, etc.).
WSType mStartReason;
// The node that implicated by start reason.
nsCOMPtr<nsINode> mStartReasonNode;
// Node/offset where ws ends.
nsCOMPtr<nsINode> mEndNode;
int32_t mEndOffset;
// Reason why ws ends (eText, eOtherBlock, etc.).
WSType mEndReason;
// The node that implicated by end reason.
nsCOMPtr<nsINode> mEndReasonNode;
// Location of first nbsp in ws run, if any.
RefPtr<dom::Text> mFirstNBSPNode;
int32_t mFirstNBSPOffset;
// Location of last nbsp in ws run, if any.
RefPtr<dom::Text> mLastNBSPNode;
int32_t mLastNBSPOffset;
// The list of nodes containing ws in this run.
nsTArray<RefPtr<dom::Text>> mNodeArray;
// The first WSFragment in the run.
WSFragment* mStartRun;
// The last WSFragment in the run, may be same as first.
WSFragment* mEndRun;
// Non-owning.
HTMLEditor* mHTMLEditor;
// Opening this class up for pillaging.
friend class HTMLEditRules;
// Opening this class up for more pillaging.
friend class HTMLEditor;
};
} // namespace mozilla
#endif // #ifndef WSRunObject_h