sl@0: // Copyright (c) 2002-2010 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: //
sl@0: 
sl@0: #ifndef LINEBREAK_H_
sl@0: #define LINEBREAK_H_
sl@0: 
sl@0: #include <e32def.h>
sl@0: class MContingentLineBreaker;
sl@0: class MContingentLineBreakerL;
sl@0: class TDesC16;
sl@0: class TUid;
sl@0: 
sl@0: 
sl@0: /**
sl@0:  This enumeration holds the possible panic codes that may be raised
sl@0:  by the LineBreak API on detecting an unrecoverable error.
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: enum TLineBreakPanic
sl@0: 	{
sl@0: 	/** Not used */
sl@0: 	ELineBreakPanic_Unknown				= 0,
sl@0: 	/** Internal error, error found in data table */
sl@0: 	ELineBreakPanic_BadTable			= 1,
sl@0: 	/** One or more of the input parameters to the interface were invalid */
sl@0: 	ELineBreakPanic_InvalidInputParam	= 2,
sl@0: 	/** Raised when an output parameter breaks an API condition */
sl@0: 	ELineBreakPanic_InvalidOutputParam	= 3,
sl@0: 	};
sl@0: 
sl@0: 
sl@0: 
sl@0: class MLineBreaker
sl@0: /**
sl@0: Customizes the Unicode line-breaking algorithm. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: 	{
sl@0: public:
sl@0: 	/** The Unicode line breaking classes; see Unicode Technical Report 14.
sl@0: 	Not a named enumerated type, so that overriding classes may add new
sl@0: 	line breaking classes freely.
sl@0: 	The description of each constant gives the name of the line-breaking
sl@0: 	class, an example and a brief, imprecise description of the default
sl@0: 	behaviour of characters of that class.	 */
sl@0: 	enum
sl@0: 		{
sl@0: 		/** Opening Punctuation (e.g. '['). Breaking after prohibited. */
sl@0: 		EOpLineBreakClass,
sl@0: 		/** Closing Punctuation (e.g. ']'). Breaking before prohibited. */
sl@0: 		EClLineBreakClass,
sl@0: 		/** Ambiguous Quotes (e.g. '"'). Breaking before and after prohibited. */
sl@0: 		EQuLineBreakClass,
sl@0: 		/** Glue (e.g. Non-breaking space). Breaking before and after prohibited
sl@0: 		unless spaces are present. */
sl@0: 		EGlLineBreakClass,
sl@0: 		/** Non-Starter (e.g. small Japanese kana). Breaking before prohibited
sl@0: 		if no spaces present. */
sl@0: 		ENsLineBreakClass,
sl@0: 		/** Exclamation or Interrogation (e.g. '?'). Like closing punctuation
sl@0: 		except before Postfix or Non-starter. */
sl@0: 		EExLineBreakClass,
sl@0: 		/** Symbol (e.g. '/'. Like Alphabetic, but allows breaking before
sl@0: 		Alphabetic. */
sl@0: 		ESyLineBreakClass,
sl@0: 		/** Numeric Infix Separator (e.g. ','). Forbids breaking after any and before
sl@0: 		Numeric. */
sl@0: 		EIsLineBreakClass,
sl@0: 		/** Numeric Prefix (e.g. '$'). Forbids breaking before Numeric. */
sl@0: 		EPrLineBreakClass,
sl@0: 		/** Numeric Postfix (e.g. '%'). Forbids breaking after Numeric. */
sl@0: 		EPoLineBreakClass,
sl@0: 		/** Numeric (e.g. '1'). */
sl@0: 		ENuLineBreakClass,
sl@0: 		/** Alphabetic (e.g. 'a'). */
sl@0: 		EAlLineBreakClass,
sl@0: 		/** Ideographic (e.g. Japanese Kanji). Generally break before or after */
sl@0: 		EIdLineBreakClass,
sl@0: 		/** Inseparable (e.g. ellipsis). Forbid breaks between Inseparables. */
sl@0: 		EInLineBreakClass,
sl@0: 		/** Hyphen (e.g. '-'). Allows a break after except before Numeric. */
sl@0: 		EHyLineBreakClass,
sl@0: 		/** Break After. Generally allow a break after. Breaking between Break
sl@0: 		Afters not separated by spaces is prohibited. */
sl@0: 		EBaLineBreakClass,
sl@0: 		/** Break Before. Generally allow a break before. Breaking between Break
sl@0: 		Befores not separated by spaces is prohibited. */
sl@0: 		EBbLineBreakClass,
sl@0: 		/** Break Before and After. Generally allow a break before or after.
sl@0: 		Breaking between Break Before and Afters is prohibited, even if spaces
sl@0: 		are present. */
sl@0: 		EB2LineBreakClass,
sl@0: 		/** Zero-Width Space. Allow a break. */
sl@0: 		EZwLineBreakClass,
sl@0: 		/** Combining Mark. Takes on the class of its base class. */
sl@0: 		ECmLineBreakClass,
sl@0: 		/** Mandatory Break. */
sl@0: 		EBkLineBreakClass,
sl@0: 		/** Carriage Return. Break after unless part of a CRLF pair. */
sl@0: 		ECrLineBreakClass,
sl@0: 		/** Line Feed. Break after. */
sl@0: 		ELfLineBreakClass,
sl@0: 		/** Surrogate. Half of a surrogate pair. */
sl@0: 		ESgLineBreakClass,
sl@0: 		/** Contingent Break (e.g. embedded pictures). Uses external
sl@0: 		information */
sl@0: 		ECbLineBreakClass,
sl@0: 
sl@0: 		/** Space. Intervening characters of class Space are indicated by
sl@0: 		aHaveSpaces in LineBreakPossible. */
sl@0: 		ESpLineBreakClass, 
sl@0: 
sl@0: 		/** Complex Context (e.g. Thai). Runs of Complex Context are passed to
sl@0: 		GetLineBreakInContext. */
sl@0: 		ESaLineBreakClass,
sl@0: 
sl@0: 		/** Ambiguous. Characters of ambiguous East Asian width are treated
sl@0: 		as Alphabetic, unless they are resolved as being "Wide", in which case
sl@0: 		they are treated as Ideographic. */
sl@0: 		EAiLineBreakClass,
sl@0: 
sl@0: 		/** The Xx class is used when the class is unknown; e.g.; outside the provided context. */
sl@0: 		EXxLineBreakClass,
sl@0: 
sl@0: 		/** The number of Unicode line break classes. */
sl@0: 		ELineBreakClasses
sl@0: 		};
sl@0: 
sl@0: 	IMPORT_C virtual TUint LineBreakClass(TUint aCode,
sl@0: 		TUint& aRangeStart, TUint& aRangeEnd) const;
sl@0: 	IMPORT_C virtual TBool LineBreakPossible(TUint aPrevClass, TUint aNextClass,
sl@0: 		TBool aHaveSpaces) const;
sl@0: 	IMPORT_C virtual TBool GetLineBreakInContext(const TDesC16& aText,
sl@0: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
sl@0: 		TInt& aBreakPos) const;
sl@0: 	IMPORT_C virtual TBool IsHangingCharacter(TUint aChar) const;
sl@0: 	IMPORT_C TBool GetLineBreak(const TDesC16& aText,
sl@0: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
sl@0: 		MContingentLineBreaker* aCbDelegate,
sl@0: 		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
sl@0: 	IMPORT_C TBool GetLineBreakL(const TDesC16& aText,
sl@0: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
sl@0: 		MContingentLineBreakerL* aCbDelegate,
sl@0: 		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
sl@0: 	IMPORT_C virtual void* ExtendedInterface(TUid& aUid) const;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: class MContingentLineBreaker
sl@0: /**
sl@0: Used to determine the line breaks around pictures and other characters with 
sl@0: the CB (contingent line break) class in situations where this operation cannot 
sl@0: leave. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: 	{
sl@0: public:
sl@0: 	/** Determines if a break is legal before the picture at aTextPosition. 
sl@0: 	
sl@0: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
sl@0: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
sl@0: 	a picture.
sl@0: 	@param aPrecedingClass The class of the character preceding aTextPosition.
sl@0: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
sl@0: 	@return ETrue if a line break is legal here. */
sl@0: 	virtual TBool IsLegalBreakBefore(TInt aTextPosition, TInt aPrecedingClass,
sl@0: 		TBool aHasSpaces) = 0;
sl@0: 	/** Determines if a break is legal after the picture at aTextPosition. 
sl@0: 	
sl@0: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
sl@0: 	in the text as supplied to MLineBreaker::GetLineBreak, which may refer to 
sl@0: 	a picture.
sl@0: 	@param aFollowingClass The class of the character immediately following aTextPosition.
sl@0: 	@param aHasSpaces ETrue if spaces separate the following class from this.
sl@0: 	@return ETrue if a line break is legal here. */
sl@0: 	virtual TBool IsLegalBreakAfter(TInt aTextPosition, TInt aFollowingClass,
sl@0: 		TBool aHasSpaces) = 0;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: 
sl@0: class MContingentLineBreakerL
sl@0: /**
sl@0: Used to determine the line breaks around pictures and other characters with 
sl@0: the CB (contingent line break) class in situations where this operation may 
sl@0: leave. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: 	{
sl@0: public:
sl@0: 	/** Determines if a break is legal before the picture at aTextPosition. 
sl@0: 	
sl@0: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
sl@0: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
sl@0: 	a picture.
sl@0: 	@param aPrecedingClass The class of the character preceding aTextPosition.
sl@0: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
sl@0: 	@return ETrue if a line break is legal here. */
sl@0: 	virtual TBool IsLegalBreakBeforeL(TInt aTextPosition, TInt aPrecedingClass,
sl@0: 		TBool aHasSpaces) = 0;
sl@0: 	/** Determines if a break is legal after the picture at aTextPosition. 
sl@0: 	
sl@0: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
sl@0: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
sl@0: 	a picture.
sl@0: 	@param aFollowingClass The class of the character immediately following aTextPosition.
sl@0: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
sl@0: 	@return ETrue if a line break is legal here. */
sl@0: 	virtual TBool IsLegalBreakAfterL(TInt aTextPosition, TInt aFollowingClass,
sl@0: 		TBool aHasSpaces) = 0;
sl@0: 	};
sl@0: 
sl@0: #endif