/*

* Copyright (c) 2008 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:      Utility for string operations in UpnpXmlParser component

*

*/

// INCLUDE FILES

#include <e32base.h>

#include "upnpxmlstringutility.h"

_LIT( KComponentLogfile, "upnpxmlstringutility.txt" );

#include "upnplog.h"

// CONSTANTS

/**

 * Range of control characters taken from http:

 * //www.w3.org/International/questions/qa-controls. 

 * Remove characters that belong to "C0" range U+0000-U+001F 

 * (0-31) and also DEL (Delete) U+007F (127). C1 range U+0080-U+009F 

 * (128-159) is ignored for now because it seems to contain ok 

 * characters like € (euro sign).

 * */

const TInt KC0RangeStart = 0;

const TInt KC0RangeEnd = 31;

const TInt KDeleteChar = 127;

// All control characters start with &#

_LIT8( KXmlControlCharStart, "&#" );

// All xml entities end with ; because they are of for &entityname;

_LIT8( KXmlEntityEnd, ";" );

// ============================ LOCAL FUNCTIONS =============================

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

// UpnpXmlStringUtility::RemoveXmlControlCharactersL

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

EXPORT_C HBufC8* UpnpXmlStringUtility::RemoveXmlControlCharactersL(

    const TDesC8& aXmlData )

    {

    __LOG( "UpnpXmlStringUtility::RemoveXmlControlCharactersL Begin" );

    HBufC8* filtrateBuf = NULL;

    //if no data

    if ( aXmlData.Length() != 0 )

        {

        //The offset of the KXmlControlCharStart from the beginning of \

          this descriptor's data

        TInt controlCharStartOffset = aXmlData.Find( KXmlControlCharStart );

        // to make sure the data contain control character.

        if ( controlCharStartOffset != KErrNotFound )

            {

            filtrateBuf = aXmlData.AllocL();

            CleanupStack::PushL( filtrateBuf );    

            //The offset of the KXmlEntityEnd from the beginning of this \

              descriptor's data

            TInt controlCharEndOffset = 0;

            //The offset of the buffer who not be checked

            TInt partofBufferOffset = 0;

            //circle find control character.

            while( controlCharStartOffset != KErrNotFound )

                {

                controlCharStartOffset += partofBufferOffset;

                partofBufferOffset = controlCharStartOffset;

                controlCharEndOffset = ( filtrateBuf->Des().

                    Mid( controlCharStartOffset ).Find( KXmlEntityEnd ) );

                if ( controlCharEndOffset != KErrNotFound )

                    {

                    TLex8 tempLex( filtrateBuf->Des().Mid( partofBufferOffset

                      + KXmlControlCharStart().Length() ,controlCharEndOffset

                      - KXmlControlCharStart().Length() ) );

                    //Parses the string to extract a signed 8-bit integer.

                    TInt tempNum;

                    User::LeaveIfError( tempLex.Val( tempNum ) );

                    if( ( tempNum >= KC0RangeStart && tempNum <= KC0RangeEnd )

                         || ( tempNum == KDeleteChar ) )

                        {

                        __LOG( "UpnpXmlStringUtility::\

RemoveXmlControlCharactersL delete control character" );

                        TPtrC8 tmpBuf = filtrateBuf->Des().Mid( 

                            partofBufferOffset, controlCharEndOffset + 

                            KXmlEntityEnd().Length() );

                        __LOG8( tmpBuf);

                        filtrateBuf->Des().Delete( partofBufferOffset, 

                        controlCharEndOffset + KXmlEntityEnd().Length() );

                        }

                    else 

                        {

                        __LOG1( "UpnpXmlStringUtility::\

RemoveXmlControlCharactersL between &# and; the Number is %d",tempNum );

                        }

                    controlCharStartOffset = partofBufferOffset;

                    controlCharStartOffset = ( filtrateBuf->Des().

                                        Mid( controlCharStartOffset ).

                                        Find( KXmlControlCharStart ) );

                    }

                else 

                    {

                    __LOG( "UpnpXmlStringUtility::RemoveXmlControlCharactersL\

 Can not find EntityEnd" );

                    User::Leave( KErrArgument );

                    }

                }

            CleanupStack::Pop( filtrateBuf );

            }

        else

            {

            // not contains control character.

            __LOG( "UpnpXmlStringUtility::RemoveXmlControlCharactersL Can \

                   not find control character!" );

            }

        }

    else

        {

        //xml data is NULL

        __LOG( "UpnpXmlStringUtility::RemoveXmlControlCharactersL the \

                            xml data is NULL" );

        }

    __LOG( "UpnpXmlStringUtility::RemoveXmlControlCharactersL End" );

    return filtrateBuf;

    }