gecko/editor/libeditor/html/nsWSRunObject.h
2012-12-09 22:53:19 +05:30

415 lines
18 KiB
C++

/* -*- 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 "nsCOMArray.h"
#include "nsCOMPtr.h"
#include "nsIContent.h"
#include "nsIDOMNode.h"
#include "nsIEditor.h"
#include "nsINode.h"
#include "nscore.h"
class nsHTMLEditor;
class nsIDOMDocument;
class nsIDOMNode;
struct DOMPoint;
// class nsWSRunObject 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 nsWSRunObject 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.
*/
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 NS_STACK_CLASS nsWSRunObject
{
public:
// public enums ---------------------------------------------------------
enum BlockBoundary
{
kBeforeBlock,
kBlockStart,
kBlockEnd,
kAfterBlock
};
enum {eBefore = 1};
enum {eAfter = 1 << 1};
enum {eBoth = eBefore | eAfter};
// constructor / destructor -----------------------------------------------
nsWSRunObject(nsHTMLEditor *aEd, nsIDOMNode *aNode, int32_t aOffset);
~nsWSRunObject();
// public methods ---------------------------------------------------------
// ScrubBlockBoundary removes any non-visible whitespace at the specified
// location relative to a block node.
static nsresult ScrubBlockBoundary(nsHTMLEditor *aHTMLEd,
nsCOMPtr<nsIDOMNode> *aBlock,
BlockBoundary aBoundary,
int32_t *aOffset = 0);
// PrepareToJoinBlocks fixes up ws at the end of aLeftParent and the
// beginning of aRightParent in preperation for them to be joined.
// example of fixup: trailingws in aLeftParent needs to be removed.
static nsresult PrepareToJoinBlocks(nsHTMLEditor *aEd,
nsIDOMNode *aLeftParent,
nsIDOMNode *aRightParent);
// 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(nsHTMLEditor *aHTMLEd,
nsCOMPtr<nsIDOMNode> *aStartNode,
int32_t *aStartOffset,
nsCOMPtr<nsIDOMNode> *aEndNode,
int32_t *aEndOffset);
// PrepareToDeleteNode fixes up ws before and after aNode in preperation
// for aNode to be deleted.
// example of fixup: trailingws before aNode needs to be removed.
static nsresult PrepareToDeleteNode(nsHTMLEditor *aHTMLEd,
nsIDOMNode *aNode);
// PrepareToSplitAcrossBlocks fixes up ws before and after
// {aSplitNode,aSplitOffset} in preperation 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(nsHTMLEditor *aHTMLEd,
nsCOMPtr<nsIDOMNode> *aSplitNode,
int32_t *aSplitOffset);
// InsertBreak inserts a br node at {aInOutParent,aInOutOffset}
// and makes any needed adjustments to ws around that point.
// example of fixup: normalws after {aInOutParent,aInOutOffset}
// needs to begin with nbsp.
nsresult InsertBreak(nsCOMPtr<nsIDOMNode> *aInOutParent,
int32_t *aInOutOffset,
nsCOMPtr<nsIDOMNode> *outBRNode,
nsIEditor::EDirection aSelect);
// InsertText inserts a string at {aInOutParent,aInOutOffset}
// and makes any needed adjustments to ws around that point.
// example of fixup: trailingws before {aInOutParent,aInOutOffset}
// needs to be removed.
nsresult InsertText(const nsAString& aStringToInsert,
nsCOMPtr<nsIDOMNode> *aInOutNode,
int32_t *aInOutOffset,
nsIDOMDocument *aDoc);
// 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 {aNode,aOffset}. If there is no visible ws qualifying
// it returns what is before the ws run. Note that
// {outVisNode,outVisOffset} is set to just AFTER the visible
// object.
void PriorVisibleNode(nsIDOMNode *aNode,
int32_t aOffset,
nsCOMPtr<nsIDOMNode> *outVisNode,
int32_t *outVisOffset,
WSType *outType);
// NextVisibleNode returns the first piece of visible thing
// after {aNode,aOffset}. If there is no visible ws qualifying
// it returns what is after the ws run. Note that
// {outVisNode,outVisOffset} is set to just BEFORE the visible
// object.
void NextVisibleNode(nsIDOMNode *aNode,
int32_t aOffset,
nsCOMPtr<nsIDOMNode> *outVisNode,
int32_t *outVisOffset,
WSType *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 struct ---------------------------------------------------------
// 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
{
nsCOMPtr<nsIDOMNode> mStartNode; // node where ws run starts
nsCOMPtr<nsIDOMNode> 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() : mStartNode(0), mEndNode(0),
mStartOffset(0), mEndOffset(0),
mType(), mLeftType(), mRightType(),
mLeft(0), mRight(0)
{
}
};
// WSPoint struct ------------------------------------------------------------
// 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 NS_STACK_CLASS WSPoint
{
nsCOMPtr<nsIContent> mTextNode;
uint32_t mOffset;
PRUnichar mChar;
WSPoint() : mTextNode(0),mOffset(0),mChar(0) {}
WSPoint(nsIDOMNode *aNode, int32_t aOffset, PRUnichar aChar) :
mTextNode(do_QueryInterface(aNode)),mOffset(aOffset),mChar(aChar)
{
if (!mTextNode->IsNodeOfType(nsINode::eDATA_NODE)) {
// Not sure if this is needed, but it'll maintain the same
// functionality
mTextNode = nullptr;
}
}
WSPoint(nsIContent *aTextNode, int32_t aOffset, PRUnichar aChar) :
mTextNode(aTextNode),mOffset(aOffset),mChar(aChar) {}
};
enum AreaRestriction
{
eAnywhere, eOutsideUserSelectAll
};
// protected methods ---------------------------------------------------------
// tons of utility methods.
/**
* 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.
*/
already_AddRefed<nsIDOMNode> GetWSBoundingParent();
nsresult GetWSNodes();
void GetRuns();
void ClearRuns();
void MakeSingleWSRun(WSType aType);
nsresult PrependNodeToList(nsIDOMNode *aNode);
nsresult AppendNodeToList(nsIDOMNode *aNode);
nsresult GetPreviousWSNode(nsIDOMNode *aStartNode,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aPriorNode);
nsresult GetPreviousWSNode(nsIDOMNode *aStartNode,
int32_t aOffset,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aPriorNode);
nsresult GetPreviousWSNode(DOMPoint aPoint,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aPriorNode);
nsresult GetNextWSNode(nsIDOMNode *aStartNode,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aNextNode);
nsresult GetNextWSNode(nsIDOMNode *aStartNode,
int32_t aOffset,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aNextNode);
nsresult GetNextWSNode(DOMPoint aPoint,
nsIDOMNode *aBlockParent,
nsCOMPtr<nsIDOMNode> *aNextNode);
nsresult PrepareToDeleteRangePriv(nsWSRunObject* aEndObject);
nsresult PrepareToSplitAcrossBlocksPriv();
nsresult DeleteChars(nsIDOMNode *aStartNode, int32_t aStartOffset,
nsIDOMNode *aEndNode, int32_t aEndOffset,
AreaRestriction aAR = eAnywhere);
WSPoint GetCharAfter(nsIDOMNode *aNode, int32_t aOffset);
WSPoint GetCharBefore(nsIDOMNode *aNode, int32_t aOffset);
WSPoint GetCharAfter(const WSPoint &aPoint);
WSPoint GetCharBefore(const WSPoint &aPoint);
nsresult ConvertToNBSP(WSPoint aPoint,
AreaRestriction aAR = eAnywhere);
void GetAsciiWSBounds(int16_t aDir, nsIDOMNode *aNode, int32_t aOffset,
nsCOMPtr<nsIDOMNode> *outStartNode, int32_t *outStartOffset,
nsCOMPtr<nsIDOMNode> *outEndNode, int32_t *outEndOffset);
void FindRun(nsIDOMNode *aNode, int32_t aOffset, WSFragment **outRun, bool after);
PRUnichar GetCharAt(nsIContent *aTextNode, int32_t aOffset);
WSPoint GetWSPointAfter(nsIDOMNode *aNode, int32_t aOffset);
WSPoint GetWSPointBefore(nsIDOMNode *aNode, int32_t aOffset);
nsresult CheckTrailingNBSPOfRun(WSFragment *aRun);
nsresult CheckTrailingNBSP(WSFragment *aRun, nsIDOMNode *aNode, int32_t aOffset);
nsresult CheckLeadingNBSP(WSFragment *aRun, nsIDOMNode *aNode, int32_t aOffset);
static nsresult ScrubBlockBoundaryInner(nsHTMLEditor *aHTMLEd,
nsCOMPtr<nsIDOMNode> *aBlock,
BlockBoundary aBoundary);
nsresult Scrub();
// member variables ---------------------------------------------------------
nsCOMPtr<nsIDOMNode> mNode; // the node passed to our constructor
int32_t mOffset; // the offset passed to our contructor
// together, the above represent the point at which we are building up ws info.
bool mPRE; // true if we are in preformatted whitespace context
nsCOMPtr<nsIDOMNode> mStartNode; // node/offset where ws starts
int32_t mStartOffset; // ...
WSType mStartReason; // reason why ws starts (eText, eOtherBlock, etc)
nsCOMPtr<nsIDOMNode> mStartReasonNode;// the node that implicated by start reason
nsCOMPtr<nsIDOMNode> mEndNode; // node/offset where ws ends
int32_t mEndOffset; // ...
WSType mEndReason; // reason why ws ends (eText, eOtherBlock, etc)
nsCOMPtr<nsIDOMNode> mEndReasonNode; // the node that implicated by end reason
nsCOMPtr<nsIDOMNode> mFirstNBSPNode; // location of first nbsp in ws run, if any
int32_t mFirstNBSPOffset; // ...
nsCOMPtr<nsIDOMNode> mLastNBSPNode; // location of last nbsp in ws run, if any
int32_t mLastNBSPOffset; // ...
nsCOMArray<nsIDOMNode> mNodeArray;//the list of nodes containing ws in this run
WSFragment *mStartRun; // the first WSFragment in the run
WSFragment *mEndRun; // the last WSFragment in the run, may be same as first
nsHTMLEditor *mHTMLEditor; // non-owning.
friend class nsHTMLEditRules; // opening this class up for pillaging
friend class nsHTMLEditor; // opening this class up for more pillaging
};
#endif