// fzipup.cpp

// 

// Copyright (c) 2008 - 2010 Accenture. All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the "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:

// Accenture - Initial contribution

//

#include <ezstream.h>

#include <ezcompressor.h>

#include <ezdecompressor.h>

#include <ezfilebuffer.h>

#include <f32file.h>

#include "fzipup.h"

const TInt KDefaultDiskNumber = 0;

const TInt CZipEntry::iOffset = _FOFF(CZipEntry, iLink);

const TUint16 KFZipVersion = 0x0014;

TInt KWindowBits = -CEZCompressor::EMaxWBits; // negative value is an undocumented feature of our zlib implementation, ensuring we do not include the zlib header in the compressed data (which we must do for zip-file format support)

const TInt KCompressedSizeRelativePosition = 18; // iCompressedSize is 18 bytes in from the current entry's LFH

//

// CBufferManager

//

CBufferManager *CBufferManager::NewLC(RFileReadStream& aInput, RFileWriteStream& aOutput, TInt aInputStreamBytes, TInt aBufferSize)

	{

	CBufferManager *bm = new (ELeave) CBufferManager(aInput, aOutput, aInputStreamBytes, aBufferSize);

	CleanupStack::PushL(bm);

	bm->ConstructL();

	return bm;

	}

CBufferManager::CBufferManager(RFileReadStream& aInput, RFileWriteStream& aOutput, TInt aInputStreamBytes, TInt aBufferSize)

:iInput(aInput), iOutput(aOutput), iInputStreamBytes(aInputStreamBytes), iBufferSize(aBufferSize), iInputDescriptor(NULL,0), iOutputDescriptor(NULL,0)

	{

	}

CBufferManager::~CBufferManager()

	{

	delete[] iInputBuffer;

	delete[] iOutputBuffer;

	}

void CBufferManager::ConstructL()

	{

	if (iInputStreamBytes < iBufferSize)

		iBufferSize = iInputStreamBytes;

	if (iBufferSize <=0)

		{

		User::Leave(KErrUnderflow);

		}

	iInputBuffer = new (ELeave) TUint8[iBufferSize];

	iOutputBuffer = new (ELeave) TUint8[iBufferSize];

	iInputDescriptor.Set(iInputBuffer,0,iBufferSize);

	iOutputDescriptor.Set(iOutputBuffer,0,iBufferSize);

	iReadLength = iBufferSize;

	}

void CBufferManager::InitializeL(CEZZStream &aZStream)

	{

	ReadInputL();

	aZStream.SetInput(iInputDescriptor);

	aZStream.SetOutput(iOutputDescriptor);

	}

void CBufferManager::NeedInputL(CEZZStream &aZStream)

	{

	ReadInputL();

	aZStream.SetInput(iInputDescriptor);

	}

void CBufferManager::NeedOutputL(CEZZStream &aZStream)

	{

	WriteOutputL(aZStream);

	aZStream.SetOutput(iOutputDescriptor);

	}

void CBufferManager::FinalizeL(CEZZStream &aZStream)

	{

	WriteOutputL(aZStream);

	}

void CBufferManager::ReadInputL()

	{

	iInput.ReadL(iInputDescriptor, iReadLength);

	iInputStreamBytes -= iReadLength;

	if (iInputStreamBytes < iBufferSize)

		{

		iReadLength = iInputStreamBytes;

		}

	if (iReadLength < 0)

		{

		User::Leave(KErrOverflow);

		}

	}

void CBufferManager::WriteOutputL(CEZZStream& aZStream)

	{

	TPtrC8 od = aZStream.OutputDescriptor();

	iOutput.WriteL(od);

	iBytesWritten += od.Size();

	}

//

// CZipEntry

// 

CZipEntry* CZipEntry::NewLC(RFs& aFs, const TDesC& aFilename, const TInt aUid)

	{

	CZipEntry* self = new (ELeave) CZipEntry(aFs, aUid);

	CleanupStack::PushL(self);

	self->ConstructL(aFilename);

	return self;

	}

CZipEntry::CZipEntry(RFs& aFs, const TInt aUid):

iFs(aFs), iUid(aUid)

	{

	iLFH.iCRC32 = crc32(iLFH.iCRC32, NULL, 0);

	}

CZipEntry::~CZipEntry()

	{

	if (iFileData)

		delete iFileData;

	if (iInput.SubSessionHandle() > 0)

		iInput.Close();

	}

void CZipEntry::ConstructL(const TDesC& aFilename)

	{

	User::LeaveIfError(iInput.Open(iFs, aFilename, EFileRead | EFileShareReadersOnly));

	// ensure aFileName is stored in accordance with zip file-format specification

	TFileName2 file(aFilename);

	if (file.HasDriveLetter())

		{

		file.Delete(0, 3); // remove '<drive>:\'

		}

	if (file.HasLeadingSlash())

		{

		file.Delete(0, 1); // remove '\'

		}

	iAsciiName.Copy(file);

	TUint8* ptr = const_cast<TUint8*> (iAsciiName.Ptr());

	TInt count = 0;

	do

		{

		if (*ptr == '\\')

			{

			*ptr = '/';

			}

		ptr++;

		} while (count++ < iAsciiName.Length());

	// config. local file header

	iLFH.iSignature = KLocalHeaderSignature;

	iLFH.iVersionNeeded = KFZipVersion;

	iLFH.iFlags = 0x0002; // best (-exx/-ex) compression was used

	iLFH.iCompressionMethod = EDeflated;

	TTime time;

	User::LeaveIfError(iInput.Modified(time));

	TDateTime td = time.DateTime();

	TUint16 param1 = td.Year() - 1980;

	TUint16 param2 = td.Month() + 1;

	TUint16 param3 = td.Day() + 1;

	iLFH.iLastModifiedFileDate = (param1 << 9) | (param2 << 5) | param3;

	param1 = td.Hour() + 1;

	param2 = td.Minute() + 1;

	param3 = td.Second() + 1;

	iLFH.iLastModifiedFileTime = (param1 << 11) | (param2 << 5) | (param3 >> 1);

	TInt uSize = 0;

	User::LeaveIfError(iInput.Size(uSize));

	if (uSize <= 0)

		{

		User::Leave(KErrAbort);

		}

	iLFH.iUncompressedSize = uSize;

	iLFH.iCompressedSize = uSize; // note: to be adjusted later once the compression is performed

	CalcCRCL();

	iLFH.iFileNameLength = iAsciiName.Size();

	iLFH.iExtraFieldLength = 0;

	// config. file header

	iFH.iSignature = KCentralDirectoryHeaderSignature;

	iFH.iMadeBy = KFZipVersion;

	iFH.iRequired = KFZipVersion;

	iFH.iFlags = iLFH.iFlags;

	iFH.iCompressionMethod = iLFH.iCompressionMethod;

	iFH.iLastModifiedFileTime = iLFH.iLastModifiedFileTime;

	iFH.iLastModifiedFileDate = iLFH.iLastModifiedFileDate;

	iFH.iCRC32 = iLFH.iCRC32;

	iFH.iCompressedSize = iLFH.iCompressedSize;	// note: to be adjusted later once the compression is performed

	iFH.iUncompressedSize = iLFH.iUncompressedSize;

	iFH.iFileNameLength = iLFH.iFileNameLength;

	iFH.iExtraFieldLength = iLFH.iExtraFieldLength;

	iFH.iFileCommentLength = 0x0000;

	iFH.iDiskNumberStart = KDefaultDiskNumber;

	iFH.iInternalFileAttributes = 0x0001;

	iFH.iExternalFileAttributes = 0x00000020;	// hardcoded to 'Archive'

	iFH.iLocalHeaderOffset = 0x00000000; // to be adjusted later (if necessary)

	}

void CZipEntry::SetOffset(TUint32 aOffset)

	{

	iFH.iLocalHeaderOffset = aOffset;

	}

TUint32 CZipEntry::ReturnOffset()

	{

	TUint32 result = iFH.iLocalHeaderOffset; // start with the offset of the LFH

	result += KLocalHeaderFixedLength; // add the size of the LFH itself

	result += iAsciiName.Size(); // add the size of the filename

	result += iLFH.iCompressedSize; // add any compressed data

	return result;

	}

TUint32 CZipEntry::FileHeaderSize()

	{

	TUint32 result = KCentralDirectoryHeaderFixedLength;

	result += iAsciiName.Size();

	return result;

	}

//

// CZipEntry::CalcCRCL

// mem. efficient means of calculating the crc on uncompressed data

// we require a maximum of KDefaultZipBufferLength heap space regardless size of data

//

void CZipEntry::CalcCRCL()

	{

	ASSERT(iInput.SubSessionHandle() > 0);

	TInt bytesRead = 0;

	TInt length = KDefaultZipBufferLength; // 32Kb

	if (iLFH.iUncompressedSize < KDefaultZipBufferLength)

		{

		length = iLFH.iUncompressedSize;

		}

	iLFH.iCRC32 = crc32(0, NULL, 0);

	HBufC8* crc = HBufC8::NewLC(length);

	TPtr8 crcPtr = crc->Des();

	User::LeaveIfError(iInput.Seek(ESeekStart, bytesRead));

	do

		{

		User::LeaveIfError(iInput.Read(crcPtr, length));

		iLFH.iCRC32 = crc32(iLFH.iCRC32, crcPtr.Ptr(), length);

		bytesRead += length;

		if ((iLFH.iUncompressedSize - bytesRead) < KDefaultZipBufferLength)

			{

			length = iLFH.iUncompressedSize - bytesRead;

			}

		} while (length > 0);

	CleanupStack::PopAndDestroy(1); // crc	

	}

//

// CZipItUp

// 

CZipItUp* CZipItUp::NewLC(RFs& aFs, TDesC& aArchive)

	{

	CZipItUp* self = new (ELeave) CZipItUp(aFs, aArchive);

	CleanupStack::PushL(self);

	self->ConstructL();

	return self;

	}		

CZipItUp::CZipItUp(RFs& aFs, TDesC& aArchive):

iFs(aFs), iFileName(aArchive), iZipMemberLinkedList(CZipEntry::iOffset), iZipMemberLinkedListIter(iZipMemberLinkedList)

	{

	}

CZipItUp::~CZipItUp()

	{

	if (iFile.SubSessionHandle() > 0)

		{

		iFile.Close();

		}

	while (!iZipMemberLinkedList.IsEmpty())

		{

		CZipEntry* entry = iZipMemberLinkedList.First();

		iZipMemberLinkedList.Remove(*entry);

		delete entry;	

		}

	iZipMemberLinkedList.Reset();

	}

void CZipItUp::ConstructL()

	{

	User::LeaveIfError(iFile.Create(iFs, iFileName, EFileStream | EFileShareExclusive));

	}

//

// CZipItUp::AddFileL

//

void CZipItUp::AddFileL(const TDesC& aFile)

	{

	if (!DuplicateEntryL(aFile))

		{

		// spawn a new zip entry, compress the file, add it to the list of zip file contained in the archive

		CZipEntry* zipEntry = CZipEntry::NewLC(iFs, aFile, ++iEntryUid);

		AddEntryL(*zipEntry);

		CleanupStack::Pop(zipEntry);

		}

	}

//

// CZipItUp::DuplicateEntryL

// run a check against the zip archive's current entries (if any!) for duplicate files

// return ETrue if a duplicate is found

//

TBool CZipItUp::DuplicateEntryL(const TDesC& aFile)

	{

	if (iZipMemberLinkedList.IsEmpty())

		{

		return EFalse;

		}

	// turn aFile into a zip-file format filename

	TFileName2 file(aFile);

	if (file.HasDriveLetter())

		{

		file.Delete(0, 3); // remove '<drive>:\'

		}

	if (file.HasLeadingSlash())

		{

		file.Delete(0, 1); // remove '\'

		}

	TBuf8<KMaxFileName> ascii;

	ascii.Copy(file);

	TUint8* ptr = const_cast<TUint8*> (ascii.Ptr());

	TInt count = 0;

	do

		{

		if (*ptr == '\\')

			{

			*ptr = '/';

			}

		ptr++;

		} while (count++ < ascii.Length());

	// iterate through zip archive entries looking for a duplicate 

	iZipMemberLinkedListIter.SetToFirst();

	CZipEntry* entry = iZipMemberLinkedListIter++;

	while (entry != NULL)

		{

		if (entry->iAsciiName == ascii)

			{

			return ETrue;

			}

		entry = iZipMemberLinkedListIter++;

		}

	return EFalse;

	}

//

// CZipItUp::AddEntryL

// Add an entry to the zip archive.

//

void CZipItUp::AddEntryL(CZipEntry& aEntry)

	{

	// append the new entry to the queue

	if (!iZipMemberLinkedList.IsEmpty())

		{

		// prior entries in the list therefore need to adjust this entry's local file header offset

		CZipEntry* lastEntry = iZipMemberLinkedList.Last();

		User::LeaveIfNull(lastEntry);

		}

	iZipMemberLinkedList.AddLast(aEntry);

	}

//

// CZipItUp::CreateZipL

// Creates the actual file, including all the previously compressed zip files in the archive

//

void CZipItUp::CreateZipL()

	{

	ASSERT(iFile.SubSessionHandle() > 0);

	if (iZipMemberLinkedList.IsEmpty())

		{

		User::Leave(KErrGeneral);

		}

	RFileWriteStream stream(iFile);

	stream.PushL();

	// initialise central directory header

	iCDT.iSignature = CZipArchive::KCentralDirectorySignature;

	iCDT.iDiskNumber = KDefaultDiskNumber;

	iCDT.iStartDiskNumber = KDefaultDiskNumber;

	iCDT.iLocalEntryCount = 0;

	iCDT.iTotalEntryCount = 0;

	iCDT.iSize = 0;

	iCDT.iCommentLength = 0;

	// iterate through each zip entry, appending local file header (LFH), file data (FD) to file

	iZipMemberLinkedListIter.SetToFirst();

	CZipEntry* entry = iZipMemberLinkedListIter++;

	CZipEntry* prior = NULL;

	User::LeaveIfNull(entry);

	do

		{

		if (prior)

			{

			// adjust file header local offset if necessary

			entry->SetOffset(prior->ReturnOffset());

			}

		// insert entry's Local File Header

		AppendLocalFileHeaderL(stream, *entry);

		// insert entry's File Data

		AppendCompressedDataL(stream, *entry);

		// adjust cdt parameters

		iCDT.iLocalEntryCount++;

		iCDT.iTotalEntryCount++;

		iCDT.iSize += entry->FileHeaderSize();

		// move onto the next entry

		prior = entry;

		entry = iZipMemberLinkedListIter++;

		} while (entry != NULL);

	// adjust cdt offset parameter

	iCDT.iOffset = iZipMemberLinkedList.Last()->ReturnOffset();

	// iterate through each zip entry, appending the central directory File Headers to file (these must go after LFH, FD entries)

	iZipMemberLinkedListIter.SetToFirst();

	entry = iZipMemberLinkedListIter++;

	do

		{

		// central directory File Header

		AppendCentralDirectoryFileHeaderL(stream, *entry);

		// move onto the next entry

		entry = iZipMemberLinkedListIter++;

		} while (entry != NULL);

	// append the central directory trailer

	AppendCentralDirectoryTrailerL(stream);	

	// commit the transaction

	stream.CommitL();

	stream.Pop();

	stream.Close();

	// go back through & adjust compressed size values for each zip entry post-mortem

	ASSERT(iFile.SubSessionHandle() == 0);

	User::LeaveIfError(iFile.Open(iFs, iFileName, EFileWrite | EFileShareExclusive));

	TInt pos = 0;

	const TInt remainder = 8; // CZipArchive::KLocalHeaderFixedLength - KCompressedSizeRelativePosition

	User::LeaveIfError(iFile.Seek(ESeekStart, pos));

	iZipMemberLinkedListIter.SetToFirst();

	entry = iZipMemberLinkedListIter++;

	do

		{

		pos += KCompressedSizeRelativePosition; // step to iCompressedSize location in the current entry's LFH

		TUint32 cs = entry->iLFH.iCompressedSize;

		TUint32 KMyByte = 0x000000FF;

		TInt bytecount = 0;

		TBuf8<8> compSize;

		do

			{

			TUint32 csChar((cs & KMyByte));

			compSize.Append(csChar);

			cs >>= 8;

			} while (++bytecount < 4); // zip-file format allows us 4 bytes only for the compressed size value

		User::LeaveIfError(iFile.Write(pos, compSize));

		pos += bytecount; // the 4 bytes we just wrote

		// step over remaing bytes to the beginning of the next entry's LFH

		pos += remainder; 

		pos += entry->iAsciiName.Size();

		pos += entry->iLFH.iCompressedSize;

		// we're now positioned at the next entry's LFH

		entry = iZipMemberLinkedListIter++;

		} while (entry != NULL);

	}

void CZipItUp::AppendLocalFileHeaderL(RFileWriteStream& aStream, CZipEntry& aZipEntry)

	{

	aStream.WriteUint32L(aZipEntry.iLFH.iSignature);

	aStream.WriteUint16L(aZipEntry.iLFH.iVersionNeeded);

	aStream.WriteUint16L(aZipEntry.iLFH.iFlags);

	aStream.WriteUint16L(aZipEntry.iLFH.iCompressionMethod);

	aStream.WriteUint16L(aZipEntry.iLFH.iLastModifiedFileTime);

	aStream.WriteUint16L(aZipEntry.iLFH.iLastModifiedFileDate);

	aStream.WriteUint32L(aZipEntry.iLFH.iCRC32);

	aStream.WriteUint32L(aZipEntry.iLFH.iCompressedSize);

	aStream.WriteUint32L(aZipEntry.iLFH.iUncompressedSize);

	aStream.WriteUint16L(aZipEntry.iLFH.iFileNameLength);

	aStream.WriteUint16L(aZipEntry.iLFH.iExtraFieldLength);

	aStream.WriteL(aZipEntry.iAsciiName);

	}

void CZipItUp::AppendCompressedDataL(RFileWriteStream& aStream, CZipEntry& aZipEntry)

	{

	// compress data & stream it to the zip archive (aStream)

	RFileReadStream inStream;

	inStream.Attach(aZipEntry.iInput); // note takes ownership of iInput subsession handle

	CBufferManager* fb = CBufferManager::NewLC(inStream, aStream, aZipEntry.iLFH.iUncompressedSize, KDefaultZipBufferLength);

	CEZCompressor* compressor = CEZCompressor::NewLC(*fb, CEZCompressor::EBestCompression, KWindowBits, CEZCompressor::EDefMemLevel, CEZCompressor::EDefaultStrategy);

	while (compressor->DeflateL()){/* do nothing */}

	// update the entry's LocalFileHeader and FileHeader

	aZipEntry.iLFH.iCompressedSize = fb->TotalBytesOut();

	aZipEntry.iFH.iCompressedSize = aZipEntry.iLFH.iCompressedSize;

	// cleanup

	CleanupStack::PopAndDestroy(2, fb); // compressor, fb

	inStream.Close();

	}

void CZipItUp::AppendCentralDirectoryFileHeaderL(RFileWriteStream& aStream, CZipEntry& aEntry)

	{

	aStream.WriteUint32L(aEntry.iFH.iSignature);

	aStream.WriteUint16L(aEntry.iFH.iMadeBy);

	aStream.WriteUint16L(aEntry.iFH.iRequired);

	aStream.WriteUint16L(aEntry.iFH.iFlags);

	aStream.WriteUint16L(aEntry.iFH.iCompressionMethod);

	aStream.WriteUint16L(aEntry.iFH.iLastModifiedFileTime);