/*

* Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "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 "filestream_private.h"

#include "logger.h"

#include "stringconv.h"

#include "utils.h"

FileStreamBuf::FileStreamBuf(const std::string &aFileName, bool aWritable, bool aSpecialTextHandling)

	: iWritable(aWritable), iSpecialTextHandling(aSpecialTextHandling)

{

	if(iWritable)

		{

		OpenUtf8FStreamForWrite(iFile, aFileName.c_str());

		}

	else

		{

		OpenUtf8FStreamForRead(iFile, aFileName.c_str());

		}

	if(iFile.fail())

		{

		dbg << Log::Indent() << "Failed to open '" << aFileName << "' for " << ((iWritable)?("output"):("input")) << "!" << Log::Endl();

		FatalError();

		}

}

static const char utf8Header[] = 

	{

		0xef, 0xbb, 0xbf

	};

static const char utf16HeaderBig[] = 

	{

		0xfe, 0xff

	};

static const char utf16HeaderLittle[] = 

	{

		0xff, 0xfe

	};

void FileStreamBuf::StripUtf8HeaderIfPresent()

{

	if(iWritable)

		{

		FatalError(); // Coding error

		}

	std::streampos savedPos = iFile.tellg();

	char header[3];

	iFile.read(header, sizeof(header));

	if(iFile.good() && memcmp(header, utf8Header, sizeof(utf8Header)) == 0)

		{

		// We read a UTF8 file header so simply return (and thereby skip it).

		return;

		}

	if(iFile.good() && memcmp(header, utf16HeaderBig, sizeof(utf16HeaderBig)) == 0)

		{

		dbg << Log::Indent() << "Input file is Big Endian UTF16 - Only UTF-8 and ASCII are supported" << Log::Endl();

		FatalError();

		}

	if(iFile.good() && memcmp(header, utf16HeaderLittle, sizeof(utf16HeaderLittle)) == 0)

		{

		dbg << Log::Indent() << "Input file is Little Endian UTF16 - Only UTF-8 and ASCII are supported" << Log::Endl();

		FatalError();

		}

	iFile.clear();

	iFile.seekg(savedPos);

}

TInt FileStreamBuf::DoReadL(TAny *aPtr,TInt aMaxLength)

{

BULLSEYE_OFF

	if(iFile.fail())

		{

		dbg << Log::Indent() << "Read error" << Log::Endl();

		FatalError(); // Read on broken stream

		}

BULLSEYE_RESTORE

	iFile.read((char *)aPtr, aMaxLength);

	if(iFile.eof())

		{

		dbg << Log::Indent() << "Encountered EOF" << Log::Endl();

		TInt len = iFile.gcount();

		if(iSpecialTextHandling)

			{

			// Add a synthetic NL to the returned data to handle a

			// token immediately before the EOF

			((TUint8 *)aPtr)[len++] = '\n';

			}

		return len;

		}

BULLSEYE_OFF

	if(iFile.fail())

		{

		dbg << Log::Indent() << "Read error" << Log::Endl();

		FatalError(); // error other than EOF

		}

BULLSEYE_RESTORE

	return iFile.gcount();

}

void FileStreamBuf::DoWriteL(const TUint8* aPtr,TInt aLength)

{

	iFile.write((const char *)aPtr, aLength);

BULLSEYE_OFF

	if(iFile.fail())

		{

		FatalError(); // error other than EOF

		}

BULLSEYE_RESTORE

	//#warning "flush all data for debugging"

	//	iFile.flush();

}

TStreamPos FileStreamBuf::DoSeekL(TMark aMark,TStreamLocation aLocation,TInt anOffset)

{

	std::ios_base::seekdir dir;

	switch(aLocation)

		{

		case EStreamBeginning:

			dir = std::ios_base::beg;

			break;

		case EStreamMark:

			dir = std::ios_base::cur;

			break;

		case EStreamEnd:

			dir = std::ios_base::end;

			break;

BULLSEYE_OFF

		default:

			FatalError();

BULLSEYE_RESTORE

		}

	if(aMark == ERead)

		{

		iFile.seekg(anOffset, dir);

BULLSEYE_OFF

		if(iFile.fail()) FatalError(); // error other than EOF

BULLSEYE_RESTORE

		return iFile.tellg();

		}

	if(aMark == EWrite)

		{

		iFile.seekp(anOffset, dir);

BULLSEYE_OFF

		if(iFile.fail()) FatalError(); // error other than EOF

BULLSEYE_RESTORE

		return iFile.tellp();

		}

	FatalError();

	return -1;

}

void FileStreamBuf::DoRelease()

{

	iFile.close();

}

FileWriteStream::FileWriteStream(const std::string &aFileName)

	: RWriteStream()

{

	iSnk = new FileStreamBuf(aFileName, true);

}

FileWriteStream::~FileWriteStream()

{

BULLSEYE_OFF

	if(iSnk)

		{

		dbg << Log::Indent() << "forgot to close FileWriteStream" << Log::Endl();

		FatalError();

		}

BULLSEYE_RESTORE

	iSnk = 0;

}

FileReadStream::FileReadStream(const std::string &aFileName, bool aSpecialTextHandling)

	: RReadStream()

{

	iSrc = new FileStreamBuf(aFileName, false, aSpecialTextHandling);

	if(aSpecialTextHandling)

		{

		static_cast<FileStreamBuf *>(iSrc)->StripUtf8HeaderIfPresent();

		}

}

FileReadStream::~FileReadStream()

{

BULLSEYE_OFF

	if(iSrc)

		{

		dbg << Log::Indent() << "forgot to close FileReadStream" << Log::Endl();

		FatalError();

		}

BULLSEYE_RESTORE

	iSrc = 0;

}

// End of file