// Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

//

#include "cstoreutilities.h"

#include <miuthdr.h>

#include <barsread.h>

// The maximum number of octets to be uuencoded on each line is 45

const TInt KUuDecodedLineLength = 45;	

// Initial size of buffer in which the "Real name <user@host>" strings

// are built before they're put into the CImHeader and the size by

// which to increment the buffer when necessary

const TInt KImapAddressSizeInc=256;

const TInt KKiloByteSize = 1024;

const TInt KBufferExtension = 4;

/**

Constructor.

*/

CStoreUtilities::CStoreUtilities(TImEncodingType aEncodingType,TUint aCharsetId,RFs& aFs)

	:iEncodingType(aEncodingType),iCharsetId(aCharsetId),iFs(aFs)

	{

	}

/**

Factory constructors.

Ownership aHeader is taken.

*/	

CStoreUtilities* CStoreUtilities::NewL(TImEncodingType aEncodingType,TUint aCharsetId,RFs& aFs)

	{

	CStoreUtilities* self=new(ELeave) CStoreUtilities(aEncodingType,aCharsetId,aFs);

	CleanupStack::PushL(self);

	self->ConstructL();

	CleanupStack::Pop();

	return self;

	}

void CStoreUtilities::ConstructL()

	{

	// Create converter objects

	iCharacterConverter=CCnvCharacterSetConverter::NewL();

	iCharConv=CImConvertCharconv::NewL(*iCharacterConverter, iFs);	

	}

/**

Destructor.

*/	

CStoreUtilities::~CStoreUtilities()

	{

	delete iCharConv;

	delete iCharacterConverter;

	delete iFooterString;

	delete iPartialLine;

	}

/**

Checks if the descriptor contains the UUE begin header

Extracts the file name if it is

*/	

TBool CStoreUtilities::CheckUUEStartL(const TDesC8& aSourceLine)

	{

	TInt sourceLength = aSourceLine.Length();

	if(sourceLength < KImcvUueStart().Length()+3) // can't be "begin ###", it's not long enough; 3=length of ###

		return EFalse;

	if(!aSourceLine.Left(KImcvUueStart().Length()).CompareF(KImcvUueStart)) // start of line might be UUE boundary

		{

		// we also need to check that the next three chars are numbers - Unix file access code

		const TUint8* sourceLinePtr = aSourceLine.Ptr();

		TInt length=KImcvUueStart().Length();// this defines length as 6 ie. "b e g i n  " 

		if( TChar(sourceLinePtr[length]).IsDigit() && 

			TChar(sourceLinePtr[length+1]).IsDigit() && 

			TChar(sourceLinePtr[length+2]).IsDigit() )

			{

			// Found 'begin ###' at the start of a line - assume this is a UUencode header

			// The attachment name in this header is ignored. We use the value from the MIME header

			return ETrue;

			}

		}

	return EFalse;

	}

/**

Appends data to partial line object extening the destination buffer as appropirate 

@param aBufferPtr the destination bufer

@param aText the data to be appended

*/	

void CStoreUtilities::AppendExtendL(HBufC8** aBufferPtr, const TDesC8& aText)

	{

	HBufC8 *buffer = *aBufferPtr;

	TInt32 space = buffer->Des().MaxLength() - (buffer->Des().Length() + aText.Length());

	if (space < 0)

		{

		TInt32 inc = (-space) + KImapAddressSizeInc - ((-space) % KImapAddressSizeInc);

		TInt32 newSize = buffer->Des().MaxLength() + inc;

		HBufC8 *newBuf = buffer->ReAllocL(newSize);

		*aBufferPtr = buffer = newBuf;

		}

	buffer->Des().Append(aText);

	}

void CStoreUtilities::AttachFooterInfoL(TInt32 aBodyPartRemainingSize,CImapSettings& aImapSettings,HBufC8*& aDecodedData)

	{

	const HBufC8* buf= aImapSettings.DefaultPartialMessageFooter();

	_LIT(KIntegerDirective,"%d");

	const TInt KNoOfDigitsInMailSize = 10; // maximum length for no of digits for remaining body parts size

	TResourceReader reader;

	reader.SetBuffer(buf);

	// Check if %d is not found in the resource string (To avoid problems due to localisation)

	if(buf->Find((TDesC8&)KIntegerDirective) == KErrNotFound)

		{

		iFooterString = (reader.ReadTPtrC()).AllocL();

		}

	else

		{

		HBufC* resourceBuf = (reader.ReadTPtrC()).AllocL();

		CleanupStack::PushL(resourceBuf);

		iFooterString = HBufC::NewL(resourceBuf->Length()+KNoOfDigitsInMailSize);

		iFooterString->Des().Format(*resourceBuf,(aBodyPartRemainingSize / KKiloByteSize));

		CleanupStack::PopAndDestroy(resourceBuf);

		}	

	//caller will have left aDecodedData on the cleanupstack

	CleanupStack::Pop(aDecodedData); 

	TInt newSize = aDecodedData->Size() + iFooterString->Size();

	aDecodedData = aDecodedData->ReAlloc(newSize);

	CleanupStack::PushL(aDecodedData);

	aDecodedData->Des().Append(*iFooterString);

	delete iFooterString;

	iFooterString = NULL;

	}

// convert text from its charset and write to richtext store. aText

// can span multiple and partial lines

void CStoreUtilities::WriteToBodyL(const TDesC8& aText,CRichText* aMessageBody)

	{

	TInt pos = aMessageBody->DocumentLength();

	// Add bits of body text, converting along the way, till no characters left

	// .. to convert.

	// Convert text before writing to body.

	TInt rem = 0;

	// there will be a max of one output char per input byte

	HBufC16* text16=HBufC16::NewLC(aText.Length());

	TPtr16 ptr16=text16->Des();

	TBool preparedToConvert = iCharConv->PrepareToConvertToFromOurCharsetL(iCharsetId);

	if (!preparedToConvert)

		{

		ptr16.Copy(aText);

		aMessageBody->InsertL(pos, ptr16);

		}

	else

		{

		TInt unconvertedChars, firstPos; // not used 

		rem = iCharConv->ConvertToOurCharsetL(aText, ptr16, 

											  unconvertedChars, firstPos);

		if (rem < 0) // error

			{

			// Copy unconverted characters.

			ptr16.Copy(aText);

			aMessageBody->InsertL(pos, ptr16);

			}

		else if (rem && rem < iLeftOver.MaxLength())

			{

			iLeftOver.Copy(aText.Right(rem));	

			}

		// convert CRLF to ELineBreak

		TInt start = 0;

		TInt length = ptr16.Length();

		if (length>0)

			{

			TInt i;

			for (i=1; i<length; i++)

				{

				if (ptr16[i-1] == KImcvCR && ptr16[i] == KImcvLF)

					{

					ptr16[i-1] = CEditableText::ELineBreak;

					// write this line to body

					TPtrC ptr = ptr16.Mid(start, i-start);

					aMessageBody->InsertL(pos, ptr);

					pos += ptr.Length();

					start = i+1;

					}

				}

			if (start != i)

				{

				TPtrC ptr = ptr16.Mid(start, i-start);

				aMessageBody->InsertL(pos, ptr);

				}

			}

		}

	CleanupStack::PopAndDestroy(text16);

	}

// Decode and store received data

HBufC8* CStoreUtilities::DecodeL(const TPtrC8& aBodyData, const TBool aEndOfStream)

	{

	// Somewhere to store decoded data, at least as long as source (plus anything we have left

	// in the partial line buffer which may now get consumed)

	TInt outputbuffersize=aBodyData.Length()+KBufferExtension;

	if (iPartialLine)

		outputbuffersize+=iPartialLine->Des().Length();

	HBufC8* decoded=HBufC8::NewL(outputbuffersize);

	TPtr8 decoded_ptr=decoded->Des();

	// Which decoder are we using?

	switch(iEncodingType)

		{

		case EEncodingTypeNone:

		case EEncodingType7Bit:

		case EEncodingType8Bit:

		case EEncodingTypeBinary:

		case EEncodingTypeUnknown:

			// Nothing to do, just copy data

			decoded->Des().Append(aBodyData);

			break;

		case EEncodingTypeBASE64:

			// Decode Base64 data: just filter it through decoder, it

			// ignores line breaks anyway.

			iB64Decoder.Decode(aBodyData,decoded_ptr);

			break;

		case EEncodingTypeUU:

			{

			TPtrC8 bodydata=aBodyData;

			// Got a partial buffer?

			if (!iPartialLine)

				{

				// Allocate buffer

				iPartialLine=HBufC8::NewL(KUuDecodedLineLength);

				iUUDecoding = EFalse;

				}

			// Decode UUEncoded data: line by line

			TBool decodeEnded = EFalse;

			TInt position=0;

			while ( bodydata.Length() && !decodeEnded )

				{

				// Find() returns the start of "\r\n". The decoding algorithm

				// requires that the encoded line contains the "\r\n".

				TInt lineEnd = bodydata.Find( _L8("\r\n") );

				if (lineEnd != KErrNotFound)

					{

					lineEnd = lineEnd + 2;

					AppendExtendL( &iPartialLine, bodydata.Left( lineEnd ));

					bodydata.Set( bodydata.Mid( lineEnd ) );

					// Check for a well-formated  begin-tag

					if ( CheckUUEStartL( iPartialLine->Des() ) )

						{

						iUUDecoding = ETrue;

						}

					else if ( iPartialLine->Compare( KImcvUueEnd ) != 0 && iUUDecoding )

						{

						// Every malformatted string is decoded as an empty string 

						// with length 0. Appending such a string is harmless.

						TPtr8 destination((unsigned char*)decoded_ptr.Ptr()+position,0,outputbuffersize-position);

						iUUDecoder.Decode(*iPartialLine,destination);

						position+=destination.Length();			

						}

					else if ( iUUDecoding )

						{

						decodeEnded = ETrue;

						iUUDecoding = EFalse;	

						}

					iPartialLine->Des().Zero();

					}

				else

					{

					AppendExtendL( &iPartialLine, bodydata);

					// advance to end of bodydata

  					bodydata.Set(bodydata.Ptr()+bodydata.Length(), 0);

					}

				}

			decoded->Des().SetLength(position);	

			break;

			}

		case EEncodingTypeQP:

			{

			TPtrC8 bodydata=aBodyData;

			// Got a partial buffer?

			if (!iPartialLine)

				{

				// Allocate buffer

				iPartialLine=HBufC8::NewL(256);

				}

			// Build buffer to decode: basically, QP decoder wants CRLF terminated

			// lines, so we build them in the iPartialLine buffer. There may be

			// stuff already there from previous data packet - so we just append.

			TInt position=0;

			while(bodydata.Length())

				{

				// Find a line break

				TInt lineend=bodydata.Find(_L8("\r\n"));

				// No break?

				if (lineend==KErrNotFound && !aEndOfStream)

					{

					// Stick it all in the partialline buffer, we should get a CRLF

					// soon...

					AppendExtendL( &iPartialLine,bodydata);

					break;

					}

				else

					{

					if (lineend==KErrNotFound)

						{

						// Append whole thing left to buffer

						AppendExtendL( &iPartialLine,bodydata);

						// advance to end of bodydata

						bodydata.Set(bodydata.Ptr()+bodydata.Length(), 0);

						}

					else

						{

						// Append to buffer up to that point (including the \r\n)

						AppendExtendL( &iPartialLine,bodydata.Left(lineend+2));

						// Remove from the buffer we're working on (including the \r\n)

						bodydata.Set(bodydata.Ptr()+lineend+2,bodydata.Length()-lineend-2);

						}

					// Decode & skip on in buffer

					TPtr8 destination((unsigned char*)decoded_ptr.Ptr()+position,0,outputbuffersize-position);

					iQPDecoder.Decode(*iPartialLine,destination);

					position+=destination.Length();

					iPartialLine->Des().Zero();

					}

				}

			// Update decoded

			decoded->Des().SetLength(position);

			break;

			}

		}

	// put back any partially converted data

	if (iLeftOver.Length())

		{

		decoded->Des().Insert(0, iLeftOver);

		iLeftOver.SetLength(0);

		}

	return decoded;

	}