// Scintilla source code edit control
/** @file Document.h
 ** Text document that handles notifications, DBCS, styling, words and end of line.
 **/
// Copyright 1998-2011 by Neil Hodgson <neilh@scintilla.org>
// The License.txt file describes the conditions under which this software may be distributed.

#ifndef DOCUMENT_H
#define DOCUMENT_H

#ifdef SCI_NAMESPACE
namespace Scintilla {
#endif

/**
 * A Position is a position within a document between two characters or at the beginning or end.
 * Sometimes used as a character index where it identifies the character after the position.
 */
typedef int Position;
const Position invalidPosition = -1;

enum EncodingFamily { efEightBit, efUnicode, efDBCS };

/**
 * The range class represents a range of text in a document.
 * The two values are not sorted as one end may be more significant than the other
 * as is the case for the selection where the end position is the position of the caret.
 * If either position is invalidPosition then the range is invalid and most operations will fail.
 */
class Range {
public:
	Position start;
	Position end;

	explicit Range(Position pos=0) :
		start(pos), end(pos) {
	}
	Range(Position start_, Position end_) :
		start(start_), end(end_) {
	}

	bool operator==(const Range &other) const {
		return (start == other.start) && (end == other.end);
	}

	bool Valid() const {
		return (start != invalidPosition) && (end != invalidPosition);
	}

	Position First() const {
		return (start <= end) ? start : end;
	}

	Position Last() const {
		return (start > end) ? start : end;
	}

	// Is the position within the range?
	bool Contains(Position pos) const {
		if (start < end) {
			return (pos >= start && pos <= end);
		} else {
			return (pos <= start && pos >= end);
		}
	}

	// Is the character after pos within the range?
	bool ContainsCharacter(Position pos) const {
		if (start < end) {
			return (pos >= start && pos < end);
		} else {
			return (pos < start && pos >= end);
		}
	}

	bool Contains(Range other) const {
		return Contains(other.start) && Contains(other.end);
	}

	bool Overlaps(Range other) const {
		return
		Contains(other.start) ||
		Contains(other.end) ||
		other.Contains(start) ||
		other.Contains(end);
	}
};

class DocWatcher;
class DocModification;
class Document;

/**
 * Interface class for regular expression searching
 */
class RegexSearchBase {
public:
	virtual ~RegexSearchBase() {}

	virtual long FindText(Document *doc, int minPos, int maxPos, const char *s,
                        bool caseSensitive, bool word, bool wordStart, int flags, int *length) = 0;

	///@return String with the substitutions, must remain valid until the next call or destruction
	virtual const char *SubstituteByPosition(Document *doc, const char *text, int *length) = 0;
};

/// Factory function for RegexSearchBase
extern RegexSearchBase *CreateRegexSearch(CharClassify *charClassTable);

struct StyledText {
	size_t length;
	const char *text;
	bool multipleStyles;
	size_t style;
	const unsigned char *styles;
	StyledText(size_t length_, const char *text_, bool multipleStyles_, int style_, const unsigned char *styles_) :
		length(length_), text(text_), multipleStyles(multipleStyles_), style(style_), styles(styles_) {
	}
	// Return number of bytes from start to before '\n' or end of text.
	// Return 1 when start is outside text
	size_t LineLength(size_t start) const {
		size_t cur = start;
		while ((cur < length) && (text[cur] != '\n'))
			cur++;
		return cur-start;
	}
	size_t StyleAt(size_t i) const {
		return multipleStyles ? styles[i] : style;
	}
};

class HighlightDelimiter {
public:
	HighlightDelimiter() : isEnabled(false) {
		Clear();
	}

	void Clear() {
		beginFoldBlock = -1;
		endFoldBlock = -1;
		firstChangeableLineBefore = -1;
		firstChangeableLineAfter = -1;
	}

	bool NeedsDrawing(int line) const {
		return isEnabled && (line <= firstChangeableLineBefore || line >= firstChangeableLineAfter);
	}

	bool IsFoldBlockHighlighted(int line) const {
		return isEnabled && beginFoldBlock != -1 && beginFoldBlock <= line && line <= endFoldBlock;
	}

	bool IsHeadOfFoldBlock(int line) const {
		return beginFoldBlock == line && line < endFoldBlock;
	}

	bool IsBodyOfFoldBlock(int line) const {
		return beginFoldBlock != -1 && beginFoldBlock < line && line < endFoldBlock;
	}

	bool IsTailOfFoldBlock(int line) const {
		return beginFoldBlock != -1 && beginFoldBlock < line && line == endFoldBlock;
	}

	int beginFoldBlock;	// Begin of current fold block
	int endFoldBlock;	// End of current fold block
	int firstChangeableLineBefore;	// First line that triggers repaint before starting line that determined current fold block
	int firstChangeableLineAfter;	// First line that triggers repaint after starting line that determined current fold block
	bool isEnabled;
};

class Document;

class LexInterface {
protected:
	Document *pdoc;
	ILexer *instance;
	bool performingStyle;	///< Prevent reentrance
public:
	explicit LexInterface(Document *pdoc_) : pdoc(pdoc_), instance(0), performingStyle(false) {
	}
	virtual ~LexInterface() {
	}
	void Colourise(int start, int end);
	int LineEndTypesSupported();
	bool UseContainerLexing() const {
		return instance == 0;
	}
};

struct RegexError : public std::runtime_error {
	RegexError() : std::runtime_error("regex failure") {}
};

/**
 */
class Document : PerLine, public IDocumentWithLineEnd, public ILoader {

public:
	/** Used to pair watcher pointer with user data. */
	struct WatcherWithUserData {
		DocWatcher *watcher;
		void *userData;
		WatcherWithUserData(DocWatcher *watcher_=0, void *userData_=0) :
			watcher(watcher_), userData(userData_) {
		}
		bool operator==(const WatcherWithUserData &other) const {
			return (watcher == other.watcher) && (userData == other.userData);
		}
	};

private:
	int refCount;
	CellBuffer cb;
	CharClassify charClass;
	CaseFolder *pcf;
	int endStyled;
	int styleClock;
	int enteredModification;
	int enteredStyling;
	int enteredReadOnlyCount;

	bool insertionSet;
	std::string insertion;

	std::vector<WatcherWithUserData> watchers;

	// ldSize is not real data - it is for dimensions and loops
	enum lineData { ldMarkers, ldLevels, ldState, ldMargin, ldAnnotation, ldSize };
	PerLine *perLineData[ldSize];

	bool matchesValid;
	RegexSearchBase *regex;

public:

	LexInterface *pli;

	int eolMode;
	/// Can also be SC_CP_UTF8 to enable UTF-8 mode
	int dbcsCodePage;
	int lineEndBitSet;
	int tabInChars;
	int indentInChars;
	int actualIndentInChars;
	bool useTabs;
	bool tabIndents;
	bool backspaceUnindents;

	DecorationList decorations;

	Document();
	virtual ~Document();

	int AddRef();
	int SCI_METHOD Release();

	virtual void Init();
	int LineEndTypesSupported() const;
	bool SetDBCSCodePage(int dbcsCodePage_);
	int GetLineEndTypesAllowed() const { return cb.GetLineEndTypes(); }
	bool SetLineEndTypesAllowed(int lineEndBitSet_);
	int GetLineEndTypesActive() const { return cb.GetLineEndTypes(); }
	virtual void InsertLine(int line);
	virtual void RemoveLine(int line);

	int SCI_METHOD Version() const {
		return dvLineEnd;
	}

	void SCI_METHOD SetErrorStatus(int status);

	int SCI_METHOD LineFromPosition(int pos) const;
	int ClampPositionIntoDocument(int pos) const;
	bool IsCrLf(int pos) const;
	int LenChar(int pos);
	bool InGoodUTF8(int pos, int &start, int &end) const;
	int MovePositionOutsideChar(int pos, int moveDir, bool checkLineEnd=true) const;
	int NextPosition(int pos, int moveDir) const;
	bool NextCharacter(int &pos, int moveDir) const;	// Returns true if pos changed
	int SCI_METHOD GetRelativePosition(int positionStart, int characterOffset) const;
	int GetRelativePositionUTF16(int positionStart, int characterOffset) const;
	int SCI_METHOD GetCharacterAndWidth(int position, int *pWidth) const;
	int SCI_METHOD CodePage() const;
	bool SCI_METHOD IsDBCSLeadByte(char ch) const;
	int SafeSegment(const char *text, int length, int lengthSegment) const;
	EncodingFamily CodePageFamily() const;

	// Gateways to modifying document
	void ModifiedAt(int pos);
	void CheckReadOnly();
	bool DeleteChars(int pos, int len);
	int InsertString(int position, const char *s, int insertLength);
	void ChangeInsertion(const char *s, int length);
	int SCI_METHOD AddData(char *data, int length);
	void * SCI_METHOD ConvertToDocument();
	int Undo();
	int Redo();
	bool CanUndo() const { return cb.CanUndo(); }
	bool CanRedo() const { return cb.CanRedo(); }
	void DeleteUndoHistory() { cb.DeleteUndoHistory(); }
	bool SetUndoCollection(bool collectUndo) {
		return cb.SetUndoCollection(collectUndo);
	}
	bool IsCollectingUndo() const { return cb.IsCollectingUndo(); }
	void BeginUndoAction() { cb.BeginUndoAction(); }
	void EndUndoAction() { cb.EndUndoAction(); }
	void AddUndoAction(int token, bool mayCoalesce) { cb.AddUndoAction(token, mayCoalesce); }
	void SetSavePoint();
	bool IsSavePoint() const { return cb.IsSavePoint(); }

	void TentativeStart() { cb.TentativeStart(); }
	void TentativeCommit() { cb.TentativeCommit(); }
	void TentativeUndo();
	bool TentativeActive() const { return cb.TentativeActive(); }

	const char * SCI_METHOD BufferPointer() { return cb.BufferPointer(); }
	const char *RangePointer(int position, int rangeLength) { return cb.RangePointer(position, rangeLength); }
	int GapPosition() const { return cb.GapPosition(); }

	int SCI_METHOD GetLineIndentation(int line);
	int SetLineIndentation(int line, int indent);
	int GetLineIndentPosition(int line) const;
	int GetColumn(int position);
	int CountCharacters(int startPos, int endPos) const;
	int CountUTF16(int startPos, int endPos) const;
	int FindColumn(int line, int column);
	void Indent(bool forwards, int lineBottom, int lineTop);
	static std::string TransformLineEnds(const char *s, size_t len, int eolModeWanted);
	void ConvertLineEnds(int eolModeSet);
	void SetReadOnly(bool set) { cb.SetReadOnly(set); }
	bool IsReadOnly() const { return cb.IsReadOnly(); }

	void DelChar(int pos);
	void DelCharBack(int pos);

	char CharAt(int position) const { return cb.CharAt(position); }
	void SCI_METHOD GetCharRange(char *buffer, int position, int lengthRetrieve) const {
		cb.GetCharRange(buffer, position, lengthRetrieve);
	}
	char SCI_METHOD StyleAt(int position) const { return cb.StyleAt(position); }
	void GetStyleRange(unsigned char *buffer, int position, int lengthRetrieve) const {
		cb.GetStyleRange(buffer, position, lengthRetrieve);
	}
	int GetMark(int line);
	int MarkerNext(int lineStart, int mask) const;
	int AddMark(int line, int markerNum);
	void AddMarkSet(int line, int valueSet);
	void DeleteMark(int line, int markerNum);
	void DeleteMarkFromHandle(int markerHandle);
	void DeleteAllMarks(int markerNum);
	int LineFromHandle(int markerHandle);
	int SCI_METHOD LineStart(int line) const;
	bool IsLineStartPosition(int position) const;
	int SCI_METHOD LineEnd(int line) const;
	int LineEndPosition(int position) const;
	bool IsLineEndPosition(int position) const;
	bool IsPositionInLineEnd(int position) const;
	int VCHomePosition(int position) const;

	int SCI_METHOD SetLevel(int line, int level);
	int SCI_METHOD GetLevel(int line) const;
	void ClearLevels();
	int GetLastChild(int lineParent, int level=-1, int lastLine=-1);
	int GetFoldParent(int line) const;
	void GetHighlightDelimiters(HighlightDelimiter &hDelimiter, int line, int lastLine);

	void Indent(bool forwards);
	int ExtendWordSelect(int pos, int delta, bool onlyWordCharacters=false);
	int NextWordStart(int pos, int delta);
	int NextWordEnd(int pos, int delta);
	int SCI_METHOD Length() const { return cb.Length(); }
	void Allocate(int newSize) { cb.Allocate(newSize); }

	struct CharacterExtracted {
		unsigned int character;
		unsigned int widthBytes;
		CharacterExtracted(unsigned int character_, unsigned int widthBytes_) : 
			character(character_), widthBytes(widthBytes_) {
		}
	};
	CharacterExtracted ExtractCharacter(int position) const;

	bool MatchesWordOptions(bool word, bool wordStart, int pos, int length) const;
	bool HasCaseFolder(void) const;
	void SetCaseFolder(CaseFolder *pcf_);
	long FindText(int minPos, int maxPos, const char *search, bool caseSensitive, bool word,
		bool wordStart, bool regExp, int flags, int *length);
	const char *SubstituteByPosition(const char *text, int *length);
	int LinesTotal() const;

	void SetDefaultCharClasses(bool includeWordClass);
	void SetCharClasses(const unsigned char *chars, CharClassify::cc newCharClass);
	int GetCharsOfClass(CharClassify::cc characterClass, unsigned char *buffer);
	void SCI_METHOD StartStyling(int position, char mask);
	bool SCI_METHOD SetStyleFor(int length, char style);
	bool SCI_METHOD SetStyles(int length, const char *styles);
	int GetEndStyled() const { return endStyled; }
	void EnsureStyledTo(int pos);
	void LexerChanged();
	int GetStyleClock() const { return styleClock; }
	void IncrementStyleClock();
	void SCI_METHOD DecorationSetCurrentIndicator(int indicator) {
		decorations.SetCurrentIndicator(indicator);
	}
	void SCI_METHOD DecorationFillRange(int position, int value, int fillLength);

	int SCI_METHOD SetLineState(int line, int state);
	int SCI_METHOD GetLineState(int line) const;
	int GetMaxLineState();
	void SCI_METHOD ChangeLexerState(int start, int end);

	StyledText MarginStyledText(int line) const;
	void MarginSetStyle(int line, int style);
	void MarginSetStyles(int line, const unsigned char *styles);
	void MarginSetText(int line, const char *text);
	void MarginClearAll();

	StyledText AnnotationStyledText(int line) const;
	void AnnotationSetText(int line, const char *text);
	void AnnotationSetStyle(int line, int style);
	void AnnotationSetStyles(int line, const unsigned char *styles);
	int AnnotationLines(int line) const;
	void AnnotationClearAll();
	
	bool AddWatcher(DocWatcher *watcher, void *userData);
	bool RemoveWatcher(DocWatcher *watcher, void *userData);

	CharClassify::cc WordCharClass(unsigned char ch) const;
	bool IsWordPartSeparator(char ch) const;
	int WordPartLeft(int pos);
	int WordPartRight(int pos);
	int ExtendStyleRange(int pos, int delta, bool singleLine = false);
	bool IsWhiteLine(int line) const;
	int ParaUp(int pos) const;
	int ParaDown(int pos) const;
	int IndentSize() const { return actualIndentInChars; }
	int BraceMatch(int position, int maxReStyle);

private:
	bool IsWordStartAt(int pos) const;
	bool IsWordEndAt(int pos) const;
	bool IsWordAt(int start, int end) const;

	void NotifyModifyAttempt();
	void NotifySavePoint(bool atSavePoint);
	void NotifyModified(DocModification mh);
};

class UndoGroup {
	Document *pdoc;
	bool groupNeeded;
public:
	UndoGroup(Document *pdoc_, bool groupNeeded_=true) :
		pdoc(pdoc_), groupNeeded(groupNeeded_) {
		if (groupNeeded) {
			pdoc->BeginUndoAction();
		}
	}
	~UndoGroup() {
		if (groupNeeded) {
			pdoc->EndUndoAction();
		}
	}
	bool Needed() const {
		return groupNeeded;
	}
};


/**
 * To optimise processing of document modifications by DocWatchers, a hint is passed indicating the
 * scope of the change.
 * If the DocWatcher is a document view then this can be used to optimise screen updating.
 */
class DocModification {
public:
	int modificationType;
	int position;
	int length;
	int linesAdded;	/**< Negative if lines deleted. */
	const char *text;	/**< Only valid for changes to text, not for changes to style. */
	int line;
	int foldLevelNow;
	int foldLevelPrev;
	int annotationLinesAdded;
	int token;

	DocModification(int modificationType_, int position_=0, int length_=0,
		int linesAdded_=0, const char *text_=0, int line_=0) :
		modificationType(modificationType_),
		position(position_),
		length(length_),
		linesAdded(linesAdded_),
		text(text_),
		line(line_),
		foldLevelNow(0),
		foldLevelPrev(0),
		annotationLinesAdded(0),
		token(0) {}

	DocModification(int modificationType_, const Action &act, int linesAdded_=0) :
		modificationType(modificationType_),
		position(act.position),
		length(act.lenData),
		linesAdded(linesAdded_),
		text(act.data),
		line(0),
		foldLevelNow(0),
		foldLevelPrev(0),
		annotationLinesAdded(0),
		token(0) {}
};

/**
 * A class that wants to receive notifications from a Document must be derived from DocWatcher
 * and implement the notification methods. It can then be added to the watcher list with AddWatcher.
 */
class DocWatcher {
public:
	virtual ~DocWatcher() {}

	virtual void NotifyModifyAttempt(Document *doc, void *userData) = 0;
	virtual void NotifySavePoint(Document *doc, void *userData, bool atSavePoint) = 0;
	virtual void NotifyModified(Document *doc, DocModification mh, void *userData) = 0;
	virtual void NotifyDeleted(Document *doc, void *userData) = 0;
	virtual void NotifyStyleNeeded(Document *doc, void *userData, int endPos) = 0;
	virtual void NotifyLexerChanged(Document *doc, void *userData) = 0;
	virtual void NotifyErrorOccurred(Document *doc, void *userData, int status) = 0;
};

#ifdef SCI_NAMESPACE
}
#endif

#endif
