/*

* Copyright (c) 2003-2006 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:  Exif tag wrapper API implementation

*

*/

// INCLUDE FILES

#include "ExifTagImpl.h"

#include "ExifCommon.h"

// ============================ CLASS TExifTagInfo =============================

// ============================ MEMBER FUNCTIONS ===============================

// -----------------------------------------------------------------------------

// TExifTagInfo::TExifTagInfo

// C++ default constructor can NOT contain any code, that

// might leave.

// -----------------------------------------------------------------------------

//

EXPORT_C TExifTagInfo::TExifTagInfo( 

   TUint16 aTagId, 

   CExifTag::TExifTagDataType aDataType, 

   TUint32 aDataCount ):

       iId( aTagId ), 

       iDataType( aDataType ), 

       iDataCount( aDataCount )

    {

    }

// ============================ CLASS CExifTag =================================

// ============================ MEMBER FUNCTIONS ===============================

// Destructor

CExifTag::~CExifTag()

    {

    }

// ============================ CLASS CExifTagImpl =============================

// ============================ MEMBER FUNCTIONS ===============================

// -----------------------------------------------------------------------------

// CExifTagImpl::CExifTagImpl

// C++ default constructor can NOT contain any code, that

// might leave.

// -----------------------------------------------------------------------------

//

CExifTagImpl::CExifTagImpl( TExifTagInfo aTagInfo ): iTagInfo( aTagInfo )

    {

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::ConstructL

// Symbian 2nd phase constructor can leave.

// -----------------------------------------------------------------------------

//

void CExifTagImpl::ConstructL( HBufC8* aDataBuffer, TBool aCheckValidity )

    {

    LOGTEXT2( _L( "ExifLib: CExifTagImpl::ConstructL entering aCheckValidity=%d" ), aCheckValidity);

    if ( !aDataBuffer ) 

        {

        LOGTEXT( _L( "ExifLib: CExifTagImpl::ConstructL leaving KErrGeneral" ) );

        User::Leave( KErrGeneral );

        }

    if ( aCheckValidity && !TExifCommon::IsValidTagId( iTagInfo.iId ) )

        {

        LOGTEXT( _L( "ExifLib: CExifTagImpl::ConstructL leaving KErrNotSupported" ) );

        User::Leave( KErrNotSupported );

        }

    TInt wordLength = 1;

    if ( iTagInfo.iDataType == ETagShort )

        {

        wordLength = 2;

        }

	else if ( ( iTagInfo.iDataType == ETagLong ) || 

        ( iTagInfo.iDataType == ETagSlong ) )

        {

        wordLength = 4;

        }

    else if ( ( iTagInfo.iDataType == ETagRational ) || 

        ( iTagInfo.iDataType == ETagSrational ) )

        {

        wordLength = 8;

        }

    else

        {

        // In practice, it never arrives here.

        }

    LOGTEXT2( _L( "ExifLib: CExifTagImpl::ConstructL wordLength=%d" ), wordLength );

    if ( aDataBuffer->Length() != 

        STATIC_CAST( TInt, wordLength * iTagInfo.iDataCount ) )

        {

        LOGTEXT3( _L( "ExifLib: CExifTagImpl::ConstructL leaving KErrArgument aDataBuffer->Length()=%d, iTagInfo.iDataCount=%d" ), aDataBuffer->Length(), iTagInfo.iDataCount);

        User::Leave( KErrArgument );

        }

    iData = aDataBuffer;

    LOGTEXT2( _L( "ExifLib: CExifTagImpl::ConstructL returning aDataBuffer->Length()=%d" ), aDataBuffer->Length() );

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::NewL

// Two-phased constructor.

// -----------------------------------------------------------------------------

//

CExifTagImpl* CExifTagImpl::NewL( 

    TUint16 aTagId, 

    CExifTag::TExifTagDataType aDataType, 

    TUint32 aDataCount, 

    HBufC8* aDataBuffer,

    TBool aCheckValidity )

    {

    if ( !aDataBuffer->Length() )

        {

        User::Leave( KErrArgument );

        }

    CExifTagImpl* self = new( ELeave ) CExifTagImpl( TExifTagInfo( aTagId, 

        aDataType, aDataCount ) );

    CleanupStack::PushL( self );

    self->ConstructL( aDataBuffer, aCheckValidity );

    CleanupStack::Pop();

    return self;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::NewL

// Two-phased constructor.

// -----------------------------------------------------------------------------

//

CExifTagImpl* CExifTagImpl::NewL( TExifTagInfo aTagInfo, HBufC8* aDataBuffer, TBool aCheckValidity )

    {

    if ( !aDataBuffer )

        {

        User::Leave( KErrGeneral );

        }

    if ( !aDataBuffer->Length() )

        {

        User::Leave( KErrArgument );

        }

    CExifTagImpl* self = new( ELeave ) CExifTagImpl( aTagInfo );

    CleanupStack::PushL( self );

    self->ConstructL( aDataBuffer, aCheckValidity );

    CleanupStack::Pop();

    return self;

    }

// Destructor

CExifTagImpl::~CExifTagImpl()

    {

    if ( iData )

        {

        delete iData;

        }

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::DuplicateL

// Duplicate constructor. Creates an exact copy instance of the tag.

// -----------------------------------------------------------------------------

//

CExifTag* CExifTagImpl::DuplicateL() const

    {

    HBufC8* buffer = iData->AllocL();

    CleanupStack::PushL( buffer );

    CExifTagImpl* tag = CExifTagImpl::NewL( iTagInfo.iId, iTagInfo.iDataType, 

        iTagInfo.iDataCount, buffer, ETrue );

    CleanupStack::Pop( buffer );

    return tag;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::TagInfo

// Returns the informative fields of a tag.

// -----------------------------------------------------------------------------

//

TExifTagInfo CExifTagImpl::TagInfo() const

    {

    return iTagInfo;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::Id

// Returns the ID of the tag.

// -----------------------------------------------------------------------------

//

TUint16 CExifTagImpl::Id() const

    {

    return iTagInfo.iId;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::DataType

// Returns the data type of the tag.

// -----------------------------------------------------------------------------

//

CExifTag::TExifTagDataType CExifTagImpl::DataType() const

    {

    return iTagInfo.iDataType;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::DataCount

// Returns the data count of the tag.

// -----------------------------------------------------------------------------

//

TUint32 CExifTagImpl::DataCount() const

    {

    return iTagInfo.iDataCount;

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::Data

// Returns the data stored in the tag.

// -----------------------------------------------------------------------------

//

TPtrC8 CExifTagImpl::Data() const

    {

    return iData->Des();

    }

// -----------------------------------------------------------------------------

// CExifTagImpl::Size

// Returns the total size of the tag in bytes

// -----------------------------------------------------------------------------

//

TUint CExifTagImpl::Size() const

    {

    // If the real tag data size is smaller than 4 bytes, then total tag size is

    // the default tag size (12). Otherwise, it is:

    // Default tag size  + real tag data size (+ 1 if tag data size is odd).

    if ( iData->Length() < 5 )

         {

         return 12; // The default tag size

         }

     else

         {

         if ( iData->Length() % 2 )

             {

             return ( 12 + iData->Length() + 1 ); // Default tag size  + ...

             }

         else

             {

             return ( 12 + iData->Length() ); // // Default tag size  + ...

             }    

         }

    }