williamr@2: // Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@4: // under the terms of "Eclipse Public License v1.0"
williamr@2: // which accompanies this distribution, and is available
williamr@4: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: //
williamr@2: 
williamr@2: #ifndef LINEBREAK_H_
williamr@2: #define LINEBREAK_H_
williamr@2: 
williamr@2: #include <e32def.h>
williamr@2: class MContingentLineBreaker;
williamr@2: class MContingentLineBreakerL;
williamr@2: class TDesC16;
williamr@2: class TUid;
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2:  This enumeration holds the possible panic codes that may be raised
williamr@2:  by the LineBreak API on detecting an unrecoverable error.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: enum TLineBreakPanic
williamr@2: 	{
williamr@2: 	/** Not used */
williamr@2: 	ELineBreakPanic_Unknown				= 0,
williamr@2: 	/** Internal error, error found in data table */
williamr@2: 	ELineBreakPanic_BadTable			= 1,
williamr@2: 	/** One or more of the input parameters to the interface were invalid */
williamr@2: 	ELineBreakPanic_InvalidInputParam	= 2,
williamr@2: 	/** Raised when an output parameter breaks an API condition */
williamr@2: 	ELineBreakPanic_InvalidOutputParam	= 3,
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: class MLineBreaker
williamr@2: /**
williamr@2: Customizes the Unicode line-breaking algorithm. 
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public:
williamr@2: 	/** The Unicode line breaking classes; see Unicode Technical Report 14.
williamr@2: 	Not a named enumerated type, so that overriding classes may add new
williamr@2: 	line breaking classes freely.
williamr@2: 	The description of each constant gives the name of the line-breaking
williamr@2: 	class, an example and a brief, imprecise description of the default
williamr@2: 	behaviour of characters of that class.	 */
williamr@2: 	enum
williamr@2: 		{
williamr@2: 		/** Opening Punctuation (e.g. '['). Breaking after prohibited. */
williamr@2: 		EOpLineBreakClass,
williamr@2: 		/** Closing Punctuation (e.g. ']'). Breaking before prohibited. */
williamr@2: 		EClLineBreakClass,
williamr@2: 		/** Ambiguous Quotes (e.g. '"'). Breaking before and after prohibited. */
williamr@2: 		EQuLineBreakClass,
williamr@2: 		/** Glue (e.g. Non-breaking space). Breaking before and after prohibited
williamr@2: 		unless spaces are present. */
williamr@2: 		EGlLineBreakClass,
williamr@2: 		/** Non-Starter (e.g. small Japanese kana). Breaking before prohibited
williamr@2: 		if no spaces present. */
williamr@2: 		ENsLineBreakClass,
williamr@2: 		/** Exclamation or Interrogation (e.g. '?'). Like closing punctuation
williamr@2: 		except before Postfix or Non-starter. */
williamr@2: 		EExLineBreakClass,
williamr@2: 		/** Symbol (e.g. '/'. Like Alphabetic, but allows breaking before
williamr@2: 		Alphabetic. */
williamr@2: 		ESyLineBreakClass,
williamr@2: 		/** Numeric Infix Separator (e.g. ','). Forbids breaking after any and before
williamr@2: 		Numeric. */
williamr@2: 		EIsLineBreakClass,
williamr@2: 		/** Numeric Prefix (e.g. '$'). Forbids breaking before Numeric. */
williamr@2: 		EPrLineBreakClass,
williamr@2: 		/** Numeric Postfix (e.g. '%'). Forbids breaking after Numeric. */
williamr@2: 		EPoLineBreakClass,
williamr@2: 		/** Numeric (e.g. '1'). */
williamr@2: 		ENuLineBreakClass,
williamr@2: 		/** Alphabetic (e.g. 'a'). */
williamr@2: 		EAlLineBreakClass,
williamr@2: 		/** Ideographic (e.g. Japanese Kanji). Generally break before or after */
williamr@2: 		EIdLineBreakClass,
williamr@2: 		/** Inseparable (e.g. ellipsis). Forbid breaks between Inseparables. */
williamr@2: 		EInLineBreakClass,
williamr@2: 		/** Hyphen (e.g. '-'). Allows a break after except before Numeric. */
williamr@2: 		EHyLineBreakClass,
williamr@2: 		/** Break After. Generally allow a break after. Breaking between Break
williamr@2: 		Afters not separated by spaces is prohibited. */
williamr@2: 		EBaLineBreakClass,
williamr@2: 		/** Break Before. Generally allow a break before. Breaking between Break
williamr@2: 		Befores not separated by spaces is prohibited. */
williamr@2: 		EBbLineBreakClass,
williamr@2: 		/** Break Before and After. Generally allow a break before or after.
williamr@2: 		Breaking between Break Before and Afters is prohibited, even if spaces
williamr@2: 		are present. */
williamr@2: 		EB2LineBreakClass,
williamr@2: 		/** Zero-Width Space. Allow a break. */
williamr@2: 		EZwLineBreakClass,
williamr@2: 		/** Combining Mark. Takes on the class of its base class. */
williamr@2: 		ECmLineBreakClass,
williamr@2: 		/** Mandatory Break. */
williamr@2: 		EBkLineBreakClass,
williamr@2: 		/** Carriage Return. Break after unless part of a CRLF pair. */
williamr@2: 		ECrLineBreakClass,
williamr@2: 		/** Line Feed. Break after. */
williamr@2: 		ELfLineBreakClass,
williamr@2: 		/** Surrogate. Half of a surrogate pair. */
williamr@2: 		ESgLineBreakClass,
williamr@2: 		/** Contingent Break (e.g. embedded pictures). Uses external
williamr@2: 		information */
williamr@2: 		ECbLineBreakClass,
williamr@2: 
williamr@2: 		/** Space. Intervening characters of class Space are indicated by
williamr@2: 		aHaveSpaces in LineBreakPossible. */
williamr@2: 		ESpLineBreakClass, 
williamr@2: 
williamr@2: 		/** Complex Context (e.g. Thai). Runs of Complex Context are passed to
williamr@2: 		GetLineBreakInContext. */
williamr@2: 		ESaLineBreakClass,
williamr@2: 
williamr@2: 		/** Ambiguous. Characters of ambiguous East Asian width are treated
williamr@2: 		as Alphabetic, unless they are resolved as being "Wide", in which case
williamr@2: 		they are treated as Ideographic. */
williamr@2: 		EAiLineBreakClass,
williamr@2: 
williamr@2: 		/** The Xx class is used when the class is unknown; e.g.; outside the provided context. */
williamr@2: 		EXxLineBreakClass,
williamr@2: 
williamr@2: 		/** The number of Unicode line break classes. */
williamr@2: 		ELineBreakClasses
williamr@2: 		};
williamr@2: 
williamr@2: 	IMPORT_C virtual TUint LineBreakClass(TUint aCode,
williamr@2: 		TUint& aRangeStart, TUint& aRangeEnd) const;
williamr@2: 	IMPORT_C virtual TBool LineBreakPossible(TUint aPrevClass, TUint aNextClass,
williamr@2: 		TBool aHaveSpaces) const;
williamr@2: 	IMPORT_C virtual TBool GetLineBreakInContext(const TDesC16& aText,
williamr@2: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
williamr@2: 		TInt& aBreakPos) const;
williamr@2: 	IMPORT_C virtual TBool IsHangingCharacter(TUint aChar) const;
williamr@2: 	IMPORT_C TBool GetLineBreak(const TDesC16& aText,
williamr@2: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
williamr@2: 		MContingentLineBreaker* aCbDelegate,
williamr@2: 		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
williamr@2: 	IMPORT_C TBool GetLineBreakL(const TDesC16& aText,
williamr@2: 		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
williamr@2: 		MContingentLineBreakerL* aCbDelegate,
williamr@2: 		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
williamr@2: 	IMPORT_C virtual void* ExtendedInterface(TUid& aUid) const;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: class MContingentLineBreaker
williamr@2: /**
williamr@2: Used to determine the line breaks around pictures and other characters with 
williamr@2: the CB (contingent line break) class in situations where this operation cannot 
williamr@2: leave. 
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public:
williamr@2: 	/** Determines if a break is legal before the picture at aTextPosition. 
williamr@2: 	
williamr@2: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
williamr@2: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
williamr@2: 	a picture.
williamr@2: 	@param aPrecedingClass The class of the character preceding aTextPosition.
williamr@2: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
williamr@2: 	@return ETrue if a line break is legal here. */
williamr@2: 	virtual TBool IsLegalBreakBefore(TInt aTextPosition, TInt aPrecedingClass,
williamr@2: 		TBool aHasSpaces) = 0;
williamr@2: 	/** Determines if a break is legal after the picture at aTextPosition. 
williamr@2: 	
williamr@2: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
williamr@2: 	in the text as supplied to MLineBreaker::GetLineBreak, which may refer to 
williamr@2: 	a picture.
williamr@2: 	@param aFollowingClass The class of the character immediately following aTextPosition.
williamr@2: 	@param aHasSpaces ETrue if spaces separate the following class from this.
williamr@2: 	@return ETrue if a line break is legal here. */
williamr@2: 	virtual TBool IsLegalBreakAfter(TInt aTextPosition, TInt aFollowingClass,
williamr@2: 		TBool aHasSpaces) = 0;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: class MContingentLineBreakerL
williamr@2: /**
williamr@2: Used to determine the line breaks around pictures and other characters with 
williamr@2: the CB (contingent line break) class in situations where this operation may 
williamr@2: leave. 
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public:
williamr@2: 	/** Determines if a break is legal before the picture at aTextPosition. 
williamr@2: 	
williamr@2: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
williamr@2: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
williamr@2: 	a picture.
williamr@2: 	@param aPrecedingClass The class of the character preceding aTextPosition.
williamr@2: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
williamr@2: 	@return ETrue if a line break is legal here. */
williamr@2: 	virtual TBool IsLegalBreakBeforeL(TInt aTextPosition, TInt aPrecedingClass,
williamr@2: 		TBool aHasSpaces) = 0;
williamr@2: 	/** Determines if a break is legal after the picture at aTextPosition. 
williamr@2: 	
williamr@2: 	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
williamr@2: 	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
williamr@2: 	a picture.
williamr@2: 	@param aFollowingClass The class of the character immediately following aTextPosition.
williamr@2: 	@param aHasSpaces ETrue if spaces separate the preceding class from this.
williamr@2: 	@return ETrue if a line break is legal here. */
williamr@2: 	virtual TBool IsLegalBreakAfterL(TInt aTextPosition, TInt aFollowingClass,
williamr@2: 		TBool aHasSpaces) = 0;
williamr@2: 	};
williamr@2: 
williamr@2: #endif