sl@0: // Copyright (c) 2003-2009 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 __TBIDI_H__
sl@0: #define __TBIDI_H__
sl@0: 
sl@0: #include "TGraphicsHarness.h"
sl@0: 
sl@0: 
sl@0: inline TBool IsSupplementary(TUint aChar)
sl@0: /**
sl@0: @param aChar The 32-bit code point value of a Unicode character.
sl@0: 
sl@0: @return True, if aChar is supplementary character; false, otherwise.
sl@0: */
sl@0: 	{
sl@0: 	return (aChar > 0xFFFF);
sl@0: 	}
sl@0: 
sl@0: inline TBool IsHighSurrogate(TText16 aInt16)
sl@0: /**
sl@0: @return True, if aText16 is high surrogate; false, otherwise.
sl@0: */
sl@0: 	{
sl@0: 	return (aInt16 & 0xFC00) == 0xD800;
sl@0: 	}
sl@0: 
sl@0: inline TBool IsLowSurrogate(TText16 aInt16)
sl@0: /**
sl@0: @return True, if aText16 is low surrogate; false, otherwise.
sl@0: */
sl@0: 	{
sl@0: 	return (aInt16 & 0xFC00) == 0xDC00;
sl@0: 	}
sl@0: 
sl@0: inline TUint JoinSurrogate(TText16 aHighSurrogate, TText16 aLowSurrogate)
sl@0: /**
sl@0: Combine a high surrogate and a low surrogate into a supplementary character.
sl@0: 
sl@0: @return The 32-bit code point value of the generated Unicode supplementary
sl@0:         character.
sl@0: */
sl@0: 	{
sl@0: 	return ((aHighSurrogate - 0xD7F7) << 10) + aLowSurrogate;
sl@0: 	}
sl@0: 
sl@0: inline TText16 GetHighSurrogate(TUint aChar)
sl@0: /**
sl@0: Retrieve the high surrogate of a supplementary character.
sl@0: 
sl@0: @param aChar The 32-bit code point value of a Unicode character.
sl@0: 
sl@0: @return High surrogate of aChar, if aChar is a supplementary character; 
sl@0:         aChar itself, if aChar is not a supplementary character.
sl@0: */
sl@0: 	{
sl@0: 	return STATIC_CAST(TText16, 0xD7C0 + (aChar >> 10));
sl@0: 	}
sl@0: 
sl@0: inline TText16 GetLowSurrogate(TUint aChar)
sl@0: /**
sl@0: Retrieve the low surrogate of a supplementary character.
sl@0: 
sl@0: @param aChar The 32-bit code point value of a Unicode character.
sl@0: 
sl@0: @return Low surrogate of aChar, if aChar is a supplementary character; 
sl@0:         zero, if aChar is not a supplementary character.
sl@0: */
sl@0: 	{
sl@0: 	return STATIC_CAST(TText16, 0xDC00 | (aChar & 0x3FF));
sl@0: 	}
sl@0: 
sl@0: void AppendCharacter(HBufC *aDes, TUint aChar);
sl@0: void AppendCharacter(TBuf<24> *aDes, TUint aChar);
sl@0: 
sl@0: 
sl@0: // Class to implement a wrapping iterator meant for extracting 16 bit characters
sl@0: // from a block of text
sl@0: // This class can handle surrogate pairs correctly.
sl@0: class TextIterator
sl@0: 	{
sl@0: public:
sl@0: 	TextIterator(const TText16* aData, const TInt aLength) : 
sl@0: 	  iData(aData), iLength(aLength), iIndex(0), iWrapped(EFalse), iCombineSurrogatePairs(ETrue)
sl@0: 		{
sl@0: 		}	
sl@0: 	TextIterator(const TText16* aData, const TInt aLength, const TInt aIndex) : 
sl@0: 		iData(aData), iLength(aLength), iIndex(aIndex), iWrapped(EFalse), iCombineSurrogatePairs(ETrue)
sl@0: 		{
sl@0: 		}
sl@0: 	TextIterator(const TText16* aData, const TInt aLength, const TInt aIndex, TBool aCombineSurrogatePairs) : 
sl@0: 		iData(aData), iLength(aLength), iIndex(aIndex), iWrapped(EFalse), iCombineSurrogatePairs(aCombineSurrogatePairs)
sl@0: 		{
sl@0: 		}
sl@0: 	// Next character from data - wrap pointer to keep within data.
sl@0: 	// Get current char, then move the internal pointer forward to next char.
sl@0: 	TUint NextChar()
sl@0: 		{
sl@0: 		TUint ch = Char();
sl@0: 		if (iCombineSurrogatePairs && IsSupplementary(ch))
sl@0: 			iIndex += 2;
sl@0: 		else
sl@0: 			iIndex += 1;
sl@0: 		// wrap
sl@0: 		if (iIndex >= iLength)
sl@0: 			{
sl@0: 			iIndex = 0;
sl@0: 			iWrapped = ETrue;
sl@0: 			}
sl@0: 		return ch;
sl@0: 		}
sl@0: 	// Move the internal pointer backward, then return the char pointed by internal char.
sl@0: 	// Panic if iIndex already = 0.
sl@0: 	TUint PreviousChar()
sl@0: 		{
sl@0: 		ASSERT(iIndex > 0);
sl@0: 		iIndex--;
sl@0: 		if (iCombineSurrogatePairs && IsLowSurrogate(iData[iIndex]))
sl@0: 			{
sl@0: 			ASSERT(iIndex > 0);
sl@0: 			iIndex--;
sl@0: 			ASSERT(IsHighSurrogate(iData[iIndex]));
sl@0: 			}
sl@0: 		else if (iCombineSurrogatePairs && IsHighSurrogate(iData[iIndex]))
sl@0: 			{
sl@0: 			ASSERT(EFalse);
sl@0: 			}
sl@0: 		else
sl@0: 			{
sl@0: 			// do nothing
sl@0: 			}
sl@0: 		return Char();
sl@0: 		}
sl@0: 	//Reset the iterator to the original values
sl@0: 	void Reset()
sl@0: 		{
sl@0: 		iIndex = 0;
sl@0: 		iWrapped = EFalse;
sl@0: 		}
sl@0: 	void SetIndex(const TInt aIndex)
sl@0: 		{
sl@0: 		iIndex = aIndex;
sl@0: 		iWrapped = EFalse;
sl@0: 		}
sl@0: 	//Has the iterator wrapped back to the start of the buffer at least once?
sl@0: 	TBool Wrapped() const
sl@0: 		{
sl@0: 		return iWrapped;
sl@0: 		}
sl@0: 	//Where is the current buffer index?
sl@0: 	TInt Index() const
sl@0: 		{
sl@0: 		return iIndex;
sl@0: 		}
sl@0: 	//Return pointer to data
sl@0: 	const TText16* Ptr() const
sl@0: 		{
sl@0: 		return iData;
sl@0: 		}
sl@0: 	//Get length of data
sl@0: 	TInt Length() const
sl@0: 		{
sl@0: 		return iLength;
sl@0: 		}
sl@0: 	//Get character at current index
sl@0: 	TUint Char() const
sl@0: 		{
sl@0: 		TUint ch = 0xFFFF;
sl@0: 		TText16 i16 = iData[iIndex];
sl@0: 		if (iCombineSurrogatePairs && IsHighSurrogate(i16))
sl@0: 			{
sl@0: 			ASSERT(iIndex+1 < iLength);
sl@0: 			TText16 low = iData[iIndex+1];
sl@0: 			ch = JoinSurrogate(i16, low);
sl@0: 			}
sl@0: 		else if (iCombineSurrogatePairs && IsLowSurrogate(i16))
sl@0: 			{
sl@0: 			ASSERT(EFalse);
sl@0: 			}
sl@0: 		else
sl@0: 			{
sl@0: 			ch = i16;
sl@0: 			}
sl@0: 		return ch;
sl@0: 		}
sl@0: 	// Fill aBuffer with a char, fill at aIndex, guarded by aMaxIndex (excluded).
sl@0: 	// After return, aIndex points to the next position, if aUpdate_aIndex=ETrue.
sl@0: 	// aUpdate_aIndex: do you want to update the parameter aIndex?
sl@0: 	// aUpdate_iIndex: do you want to update the member variable iIndex?
sl@0: 	// aChar: [out] current char
sl@0: 	TBool NextCharInto(TDes &aBuffer, TInt &aIndex, TInt aMaxIndex=-1, TBool aUpdate_aIndex=ETrue, TBool aUpdate_iIndex=ETrue, TUint *aChar=NULL)
sl@0: 		{
sl@0: 		if (aMaxIndex < 0)
sl@0: 			aMaxIndex = aBuffer.Length();
sl@0: 		if (aIndex >= aMaxIndex)
sl@0: 			return EFalse;
sl@0: 
sl@0: 		TUint ch = Char();
sl@0: 		if (iCombineSurrogatePairs && IsSupplementary(ch))
sl@0: 			{
sl@0: 			if (aIndex+1 >= aMaxIndex)
sl@0: 				return EFalse;
sl@0: 			aBuffer[aIndex] = GetHighSurrogate(ch);
sl@0: 			aBuffer[aIndex+1] = GetLowSurrogate(ch);
sl@0: 			if (aUpdate_aIndex)
sl@0: 				aIndex += 2;
sl@0: 			}
sl@0: 		else
sl@0: 			{
sl@0: 			aBuffer[aIndex] = (TText16)ch;
sl@0: 			if (aUpdate_aIndex)
sl@0: 				aIndex++;
sl@0: 			}
sl@0: 		if (aChar)
sl@0: 			*aChar = ch;
sl@0: 		if (aUpdate_iIndex)
sl@0: 			{
sl@0: 			if (iCombineSurrogatePairs && IsSupplementary(ch))
sl@0: 				iIndex += 2;
sl@0: 			else
sl@0: 				iIndex += 1;
sl@0: 			if (iIndex >= iLength)
sl@0: 				{
sl@0: 				iIndex = 0;
sl@0: 				iWrapped = ETrue;
sl@0: 				}
sl@0: 			}
sl@0: 		return ETrue;
sl@0: 		}
sl@0: 	// Fill aBuffer from aIndex to aMaxIndex (excluded).
sl@0: 	// aMaxIndex=-1 means fill to index=aBuffer.Length.
sl@0: 	// After return, aIndex points to the next position, if aUpdate_aIndex=ETrue.
sl@0: 	TBool FillInto(TDes &aBuffer, TInt &aIndex, TInt aMaxIndex=-1)
sl@0: 		{
sl@0: 		if (aMaxIndex == -1)
sl@0: 			aMaxIndex = aBuffer.Length();
sl@0: 		while (aIndex < aMaxIndex)
sl@0: 			{
sl@0: 			TBool b = NextCharInto(aBuffer, aIndex, aMaxIndex);
sl@0: 			if (!b)
sl@0: 				{
sl@0: 				return ETrue;
sl@0: 				}
sl@0: 			}
sl@0: 		return ETrue;
sl@0: 		}
sl@0: 
sl@0: private:
sl@0: 	const TText16* iData;
sl@0: 	TInt  iLength;
sl@0: 	TInt  iIndex;
sl@0: 	TBool iWrapped;
sl@0: 	TBool iCombineSurrogatePairs;	// ETrue = combine surrogates; EFalse = take single surrogate as character
sl@0: 	};
sl@0: 
sl@0: class CTBiDiStep : public CTGraphicsStep
sl@0: 	{
sl@0: public:
sl@0: 	CTBiDiStep();
sl@0: protected:	
sl@0: 	//from CTGraphicsStep
sl@0: 	virtual CTGraphicsBase* CreateTestL();
sl@0: 	};
sl@0: 
sl@0: _LIT(KTBiDiStep,"TBiDi");
sl@0: 
sl@0: 
sl@0: #endif