sl@0: // Copyright (c) 2002-2009 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: #include "BidiVisual.h"
sl@0: #include "BidiCopy.h"
sl@0: #include "BidiTextImp.h"
sl@0: #include "BidiCompact.h"
sl@0: 
sl@0: extern void BidiPanic(TInt aError);
sl@0: 
sl@0: /** Construct the class with a full paragraph of text and the run array to be used 
sl@0: to hold all the runs. 
sl@0: 
sl@0: @param aText The text to be analyzed. This must not be de-allocated until 
sl@0: all operations on it through this class have been completed.
sl@0: @param aRightToLeft Paragraph directionality.
sl@0: @param aRunInfoArray The array to be used to hold the run information. This 
sl@0: must not be de-allocated until all operations on it through this class have 
sl@0: been completed. Ownership is not passed.
sl@0: @param aRunInfoLength The number of TRunInfo<\code> objects in aRunInfoArray. */
sl@0: EXPORT_C TBidiLogicalToVisual::TBidiLogicalToVisual(
sl@0: 	const TDesC& aText,
sl@0: 	TBool aRightToLeft,
sl@0: 	TBidirectionalState::TRunInfo* aRunInfoArray,
sl@0: 	TInt aRunInfoLength)
sl@0: 	: iText(aText), iRightToLeft(aRightToLeft),
sl@0: 	iRunInfoArray(aRunInfoArray), iRunInfoArrayLength(aRunInfoLength), iRuns(aRunInfoLength)
sl@0: 	{
sl@0: 	}
sl@0: 
sl@0: /** Construct the class with a full paragraph of text and the run array to be used 
sl@0: to hold all the runs. Directionality is taken as the implicit directionality 
sl@0: of the text passed. 
sl@0: 
sl@0: @param aText The text to be analyzed. This must not be de-allocated until 
sl@0: all operations on it through this class have been completed.
sl@0: @param aRunInfoArray The array to be used to hold the run information. This 
sl@0: must not be de-allocated until all operations on it through this class have 
sl@0: been completed. Ownership is not passed.
sl@0: @param aRunInfoLength The number of TRunInfo objects in aRunInfoArray. */
sl@0: EXPORT_C TBidiLogicalToVisual::TBidiLogicalToVisual(
sl@0: 	const TDesC& aText,
sl@0: 	TBidirectionalState::TRunInfo* aRunInfoArray,
sl@0: 	TInt aRunInfoLength)
sl@0: 	: iText(aText),
sl@0: 	iRunInfoArray(aRunInfoArray), iRunInfoArrayLength(aRunInfoLength), iRuns(aRunInfoLength)
sl@0: 	{
sl@0: 	iRightToLeft = BidiCopy::ImplicitDirectionalityIsRightToLeft(
sl@0: 		aText.Ptr(), aText.Length(), 0);
sl@0: 	}
sl@0: 
sl@0: /** Process the text. This must be called before any call to GetVisualLine. 
sl@0: 
sl@0: @return The number of runs that were or would be required to reorder the complete 
sl@0: line. If this is less than the value passed into the constructor as aRunInfoLength, 
sl@0: the full text will not be able to be Reordered. */
sl@0: EXPORT_C TInt TBidiLogicalToVisual::Reorder()
sl@0: 	{
sl@0: 	TInt required = TBidirectionalState::GenerateBdRunArray(
sl@0: 		iText.Ptr(), iText.Length(), iRunInfoArray, iRunInfoArrayLength);
sl@0: 	iRuns = Min(required, iRunInfoArrayLength);
sl@0: 	TBidirectionalState state;
sl@0: 	state.ReorderLine(iRunInfoArray, iRuns, ETrue, ETrue, iRightToLeft,
sl@0: 		TChar::EOtherNeutral, TChar::EOtherNeutral);
sl@0: 	return required;
sl@0: 	}
sl@0: 
sl@0: /** Get a line of visually ordered text. 
sl@0: 
sl@0: @param aLine Line of text in visual order. There must be aEnd - aStart + 4 
sl@0: characters available in the buffer. Only characters within the range aStart 
sl@0: to aEnd, plus perhaps a truncation character and up to two zero-width joiners 
sl@0: will be present in the string at the end.
sl@0: @param aStart The first character in the text that is to be on the line.
sl@0: @param aEnd One plus the last character in the test that is to be on the line.
sl@0: @param aTruncationChar The character to mark the end of the text, if appropriate, 
sl@0: or 0xFFFF if no truncation character is to be used. */ 
sl@0: EXPORT_C void TBidiLogicalToVisual::GetVisualLine(TDes& aLine,
sl@0: 	TInt aStart, TInt aEnd, TChar aTruncationChar)
sl@0: 	{
sl@0: 	__ASSERT_ALWAYS(aEnd - aStart + KMinCharAvailable <= aLine.MaxLength(), BidiPanic(KErrArgument));
sl@0: 
sl@0: 	if(iText.Length() == 0)
sl@0: 		{
sl@0: 		aLine.Zero();
sl@0: 		return;//We can't do anything with iText, if its length is 0.
sl@0: 		}
sl@0: 
sl@0: 	TRunInfoCompact::TReorderingContext context;
sl@0: 
sl@0: 	const TText* input = &iText[0];
sl@0: 	context.iStart = aStart;
sl@0: 	context.iEnd = aEnd;
sl@0: 	context.iTruncation = aTruncationChar;
sl@0: 	context.iSource = input;
sl@0: 	context.iJoinsAtStart = TRunInfoCompact::JoinBefore(input, aStart);
sl@0: 	context.iJoinsAtEnd = aEnd < iText.Length() ? TRunInfoCompact::JoinBefore(input, aEnd) : EFalse;
sl@0: 
sl@0: 	aLine.FillZ(1);
sl@0: 	TText* output = &aLine[0];
sl@0: 	TText* outputStart = output;
sl@0: 	TBidirectionalState::TRunInfo* endInfo = iRunInfoArray + iRuns;
sl@0: 	for (TBidirectionalState::TRunInfo* currentInfo = iRunInfoArray;
sl@0: 		currentInfo != endInfo; ++currentInfo)
sl@0: 		{
sl@0: 		TRunInfoCompact info(currentInfo->iStart,
sl@0: 			currentInfo->iLength, currentInfo->iDirection);
sl@0: 		output = info.Reorder(output, context);
sl@0: 		}
sl@0: 	aLine.SetLength(output - outputStart);
sl@0: 	}