/*************************************************************************
 *
 *  $RCSfile: XUnbufferedStream.cxx,v $
 *
 *  $Revision: 1.5 $
 *
 *  last change: $Author: hr $ $Date: 2003-03-26 14:13:45 $
 *
 *  The Contents of this file are made available subject to the terms of
 *  either of the following licenses
 *
 *         - GNU Lesser General Public License Version 2.1
 *         - Sun Industry Standards Source License Version 1.1
 *
 *  Sun Microsystems Inc., October, 2000
 *
 *  GNU Lesser General Public License Version 2.1
 *  =============================================
 *  Copyright 2000 by Sun Microsystems, Inc.
 *  901 San Antonio Road, Palo Alto, CA 94303, USA
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License version 2.1, as published by the Free Software Foundation.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *  MA  02111-1307  USA
 *
 *
 *  Sun Industry Standards Source License Version 1.1
 *  =================================================
 *  The contents of this file are subject to the Sun Industry Standards
 *  Source License Version 1.1 (the "License"); You may not use this file
 *  except in compliance with the License. You may obtain a copy of the
 *  License at http://www.openoffice.org/license.html.
 *
 *  Software provided under this License is provided on an "AS IS" basis,
 *  WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 *  WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
 *  MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
 *  See the License for the specific provisions governing your rights and
 *  obligations concerning the Software.
 *
 *  The Initial Developer of the Original Code is: Sun Microsystems, Inc.
 *
 *  Copyright: 2000 by Sun Microsystems, Inc.
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): Martin Gallwey (gallwey@sun.com)
 *
 *
 ************************************************************************/
#ifndef _XUNBUFFERED_STREAM_HXX
#include <XUnbufferedStream.hxx>
#endif
#ifndef _ENCRYPTION_DATA_HXX_
#include <EncryptionData.hxx>
#endif
#ifndef _COM_SUN_STAR_PACKAGES_ZIP_ZIPCONSTANTS_HPP_
#include <com/sun/star/packages/zip/ZipConstants.hpp>
#endif
#ifndef _COM_SUN_STAR_PACKAGES_ZIP_ZIPIOEXCEPTION_HPP_
#include <com/sun/star/packages/zip/ZipIOException.hpp>
#endif
#ifndef _PACKAGE_CONSTANTS_HXX_
#include <PackageConstants.hxx>
#endif
#ifndef _RTL_CIPHER_H_
#include <rtl/cipher.h>
#endif
#ifndef _ZIP_FILE_HXX
#include <ZipFile.hxx>
#endif
#ifndef _ENCRYPTED_DATA_HEADER_HXX_
#include <EncryptedDataHeader.hxx>
#endif
#include <algorithm>

using namespace com::sun::star::packages::zip::ZipConstants;
using namespace com::sun::star::io;
using namespace com::sun::star::uno;
using com::sun::star::lang::IllegalArgumentException;
using com::sun::star::packages::zip::ZipIOException;
using ::rtl::OUString;

XUnbufferedStream::XUnbufferedStream( ZipEntry & rEntry,
                           com::sun::star::uno::Reference < com::sun::star::io::XInputStream > xNewZipStream,
                           const vos::ORef < EncryptionData > &rData,
                           sal_Bool bNewRawStream,
                           sal_Bool bIsEncrypted )
: maEntry ( rEntry )
, mxData ( rData )
, mbRawStream ( bNewRawStream )
, mbFinished ( sal_False )
, mxZipStream ( xNewZipStream )
, mxZipSeek ( xNewZipStream, UNO_QUERY )
, maInflater ( sal_True )
, maCipher ( NULL )
, mnMyCurrent ( 0 )
, mnZipEnd ( 0 )
, mnZipSize ( 0 )
, mnZipCurrent ( 0 )
, mnHeaderToRead ( 0 )
{
    mnZipCurrent = maEntry.nOffset;
    if ( mbRawStream )
    {
        mnZipSize = maEntry.nMethod == DEFLATED ? maEntry.nCompressedSize : maEntry.nSize;
        mnZipEnd = maEntry.nOffset + mnZipSize;
    }
    else
    {
        mnZipSize = maEntry.nSize;
        mnZipEnd = maEntry.nMethod == DEFLATED ? maEntry.nOffset + maEntry.nCompressedSize : maEntry.nOffset + maEntry.nSize;
    }
    sal_Bool bHaveEncryptData = ( !rData.isEmpty() && rData->aSalt.getLength() && rData->aInitVector.getLength() && rData->nIterationCount != 0 ) ? sal_True : sal_False;
    sal_Bool bMustDecrypt = ( !bNewRawStream && bHaveEncryptData && bIsEncrypted ) ? sal_True : sal_False;

    if ( bMustDecrypt )
        ZipFile::StaticGetCipher ( rData, maCipher );
    if ( bHaveEncryptData && !bMustDecrypt && bIsEncrypted )
    {
        // if we have the data needed to decrypt it, but didn't want it decrypted (or
        // we couldn't decrypt it due to wrong password), then we prepend this
        // data to the stream

        // Make a buffer big enough to hold both the header and the data itself
        maHeader.realloc  ( n_ConstHeaderSize +
                            rData->aInitVector.getLength() +
                            rData->aSalt.getLength() +
                            rData->aDigest.getLength() );
        sal_Int8 * pHeader = maHeader.getArray();
        ZipFile::StaticFillHeader ( rData, rEntry.nSize, pHeader );
        mnHeaderToRead = static_cast < sal_Int16 > ( maHeader.getLength() );
    }
}

XUnbufferedStream::~XUnbufferedStream()
{
    if ( maCipher )
        rtl_cipher_destroy ( maCipher );
}

sal_Int32 SAL_CALL XUnbufferedStream::readBytes( Sequence< sal_Int8 >& aData, sal_Int32 nBytesToRead )
        throw( NotConnectedException, BufferSizeExceededException, IOException, RuntimeException)
{
    sal_Int32 nRequestedBytes = nBytesToRead;
    if ( mnMyCurrent + nRequestedBytes > mnZipSize )
        nRequestedBytes = static_cast < sal_Int32 > ( mnZipSize - mnMyCurrent );

    sal_Int32 nRead = 0, nLastRead = 0, nTotal = 0;
    aData.realloc ( nRequestedBytes );
    if ( nRequestedBytes )
    {
        if ( mnHeaderToRead )
        {
            sal_Int16 nToRead = static_cast < sal_Int16 > ( nRequestedBytes > mnHeaderToRead ? mnHeaderToRead : nRequestedBytes );
            memcpy ( aData.getArray(), maHeader.getConstArray() + maHeader.getLength() - mnHeaderToRead, nToRead );
            mnHeaderToRead -= nToRead;
            if ( mnHeaderToRead == 0 )
                maHeader.realloc ( 0 );
        }


        if ( !mbRawStream )
        {
            while ( 0 == ( nLastRead = maInflater.doInflateSegment( aData, nRead, aData.getLength() - nRead ) ) ||
                  ( nRead + nLastRead != nRequestedBytes && mnZipCurrent < mnZipEnd ) )
            {
                nRead += nLastRead;

                if ( nRead > nRequestedBytes )
                    throw RuntimeException(
                        OUString( RTL_CONSTASCII_USTRINGPARAM( "Should not be possible to read more then requested!" ) ),
                        Reference< XInterface >() );

                if ( maInflater.finished() )
                    throw ZipIOException( OUString( RTL_CONSTASCII_USTRINGPARAM( "The stream seems to be broken!" ) ),
                                        Reference< XInterface >() );

                if ( maInflater.needsDictionary() )
                    throw ZipIOException( OUString( RTL_CONSTASCII_USTRINGPARAM( "Dictionaries are not supported!" ) ),
                                        Reference< XInterface >() );

                sal_Int32 nDiff = static_cast < sal_Int32 > ( mnZipEnd - mnZipCurrent );
                if ( nDiff > 0 )
                {
                    mxZipSeek->seek ( mnZipCurrent );
                    sal_Int32 nToRead = std::min ( nDiff, std::max ( nRequestedBytes, 8192L ) );
                    sal_Int32 nZipRead = mxZipStream->readBytes ( maCompBuffer, nToRead );
                    mnZipCurrent += nZipRead;
                    // maCompBuffer now has the uncompressed data, check if we need to decrypt
                    // before passing to the Inflater
                    if ( maCipher )
                    {
                        maCRC.update( maCompBuffer );
                        Sequence < sal_Int8 > aCryptBuffer ( nZipRead );
                        rtlCipherError aResult = rtl_cipher_decode ( maCipher,
                                      maCompBuffer.getConstArray(),
                                      nZipRead,
                                      reinterpret_cast < sal_uInt8 * > (aCryptBuffer.getArray()),
                                      nZipRead);
                        OSL_ASSERT (aResult == rtl_Cipher_E_None);
                        maCompBuffer = aCryptBuffer; // Now it holds the decrypted data

                    }
                    maInflater.setInput ( maCompBuffer );
                }
                else
                {
                    throw ZipIOException( OUString( RTL_CONSTASCII_USTRINGPARAM( "The stream seems to be broken!" ) ),
                                        Reference< XInterface >() );
                }
            }
        }
        else
        {
            sal_Int64 nDiff = mnZipEnd - mnZipCurrent;
            mxZipSeek->seek ( mnZipCurrent );
            nRead = mxZipStream->readBytes (
                                        aData,
                                        static_cast < sal_Int32 > ( nDiff < nRequestedBytes ? nDiff : nRequestedBytes ) );

            mnZipCurrent += nRead;
        }

        mnMyCurrent += nRead + nLastRead;
        nTotal = nRead + nLastRead;
        if ( nTotal < nRequestedBytes)
            aData.realloc ( nTotal );

        if ( !mbRawStream )
        {
            if ( !maCipher )
                maCRC.update( aData );

            if ( mnZipSize == mnMyCurrent && maCRC.getValue() != maEntry.nCrc )
                throw ZipIOException( OUString( RTL_CONSTASCII_USTRINGPARAM( "The stream seems to be broken!" ) ),
                                    Reference< XInterface >() );
        }
    }

    return nTotal;
}

sal_Int32 SAL_CALL XUnbufferedStream::readSomeBytes( Sequence< sal_Int8 >& aData, sal_Int32 nMaxBytesToRead )
        throw( NotConnectedException, BufferSizeExceededException, IOException, RuntimeException)
{
    return readBytes ( aData, nMaxBytesToRead );
}
void SAL_CALL XUnbufferedStream::skipBytes( sal_Int32 nBytesToSkip )
        throw( NotConnectedException, BufferSizeExceededException, IOException, RuntimeException)
{
    if ( nBytesToSkip )
    {
        Sequence < sal_Int8 > aSequence ( nBytesToSkip );
        readBytes ( aSequence, nBytesToSkip );
    }
}

sal_Int32 SAL_CALL XUnbufferedStream::available(  )
        throw( NotConnectedException, IOException, RuntimeException)
{
    return static_cast < sal_Int32 > ( mnZipSize - mnMyCurrent );
}

void SAL_CALL XUnbufferedStream::closeInput(  )
        throw( NotConnectedException, IOException, RuntimeException)
{
}
/*
void SAL_CALL XUnbufferedStream::seek( sal_Int64 location )
        throw( IllegalArgumentException, IOException, RuntimeException)
{
}
sal_Int64 SAL_CALL XUnbufferedStream::getPosition(  )
        throw(IOException, RuntimeException)
{
    return mnMyCurrent;
}
sal_Int64 SAL_CALL XUnbufferedStream::getLength(  )
        throw(IOException, RuntimeException)
{
    return mnZipSize;
}
*/