int
OggSoundFile::cb_seek(void* source, ogg_int64_t offset, int whence)
{
  PHYSFS_file* file = reinterpret_cast<PHYSFS_file*> (source);

  switch(whence) {
    case SEEK_SET:
      if(PHYSFS_seek(file, static_cast<PHYSFS_uint64> (offset)) == 0)
        return -1;
      break;
    case SEEK_CUR:
      if(PHYSFS_seek(file, PHYSFS_tell(file) + offset) == 0)
        return -1;
      break;
    case SEEK_END:
      if(PHYSFS_seek(file, PHYSFS_fileLength(file) + offset) == 0)
        return -1;
      break;
    default:
#ifdef DEBUG
      assert(false);
#else
      return -1;
#endif
  }
  return 0;
}

int OSBasics::seek(OSFILE * stream, long int offset, int origin ) {
	switch(stream->fileType) {
		case OSFILE::TYPE_FILE:
			return fseek(stream->file, offset, origin);
			break;
		case OSFILE::TYPE_ARCHIVE_FILE:
			switch(origin) {
				case SEEK_SET:
					return PHYSFS_seek(stream->physFSFile, offset);
				break;
				case SEEK_CUR: {
					PHYSFS_sint64 curoffset = PHYSFS_tell(stream->physFSFile);					
					return PHYSFS_seek(stream->physFSFile, curoffset+offset);				
				}
				break;
				case SEEK_END: {
					PHYSFS_sint64 fileLength =  PHYSFS_fileLength(stream->physFSFile);
					return PHYSFS_seek(stream->physFSFile, fileLength-offset);
				}
				break;
			}
			break;			
	}
	return 0;	
}

        bool FileReadObject::seek(long finalPos, bool relativeMovement)
        {
            if (relativeMovement)
                finalPos += PHYSFS_tell(mFileHandle);

            return PHYSFS_seek(mFileHandle, finalPos);
        }

	int File::tell()
	{
		if(file == 0)
			return -1;

		return (int)PHYSFS_tell(file);
	}

uint FileStream::tell()
{
    if(!m_caching)
        return PHYSFS_tell(m_fileHandle);
    else
        return m_pos;
}

size_t
WavSoundFile::read(void* buffer, size_t buffer_size)
{
  PHYSFS_sint64 end = datastart + size;
  PHYSFS_sint64 cur = PHYSFS_tell(file);
  if(cur >= end)
    return 0;

  size_t readsize = std::min(static_cast<size_t> (end - cur), buffer_size);
  if(PHYSFS_read(file, buffer, readsize, 1) != 1)
    throw SoundError("read error while reading samples");

#ifdef WORDS_BIGENDIAN
  if (bits_per_sample != 16)
    return readsize;
  char *tmp = (char*)buffer;

  size_t i;
  char c;
  for (i = 0; i < readsize / 2; i++)
  {
    c          = tmp[2*i];
    tmp[2*i]   = tmp[2*i+1];
    tmp[2*i+1] = c;
  }

  buffer = tmp;
#endif

  return readsize;
}

bool physfsFile::prepareRead() {
	PHYSFS_uint64 pos = PHYSFS_tell(fhandle);
	PHYSFS_close(fhandle);
	fhandle = PHYSFS_openRead(pname);
	PHYSFS_seek(fhandle, pos);
	//LOG_MSG("Goto read (%s at %i)",pname,PHYSFS_tell(fhandle));
    return true;
}

int PHYSFS_fixedEof(PHYSFS_File *handle) {
    if((PHYSFS_eof(handle)) ||
       (PHYSFS_fileLength(handle) == PHYSFS_tell(handle))) {
        return 1;
    }

    return 0;
}

static int wz_oggVorbis_seek(void *datasource, ogg_int64_t offset, int whence)
{
	PHYSFS_file* fileHandle;
	BOOL allowSeeking;
	int newPos;

	ASSERT(datasource != NULL, "NULL decoder passed!");

	fileHandle = ((struct OggVorbisDecoderState*)datasource)->fileHandle;
	ASSERT(fileHandle != NULL, "Bad PhysicsFS file handle passed in");

	allowSeeking = ((struct OggVorbisDecoderState*)datasource)->allowSeeking;

	if (!allowSeeking)
		return -1;

	switch (whence)
	{
		// Seek to absolute position
		case SEEK_SET:
			newPos = offset;
			break;

		// Seek `offset` ahead
		case SEEK_CUR:
		{
			int curPos = PHYSFS_tell(fileHandle);
			if (curPos == -1)
				return -1;

			newPos = curPos + offset;
			break;
		}

		// Seek backwards from the end of the file
		case SEEK_END:
		{
			int fileSize = PHYSFS_fileLength(fileHandle);
			if (fileSize == -1)
				return -1;

			newPos = fileSize - 1 - offset;
			break;
		}

		// unrecognized seek instruction
		default:
			// indicate failure
			return -1;
	}

	// PHYSFS_seek return value of non-zero means success
	if (PHYSFS_seek(fileHandle, newPos) != 0)
		return newPos;   // success
	else
		return -1;  // failure
}

	pos_type seekpos(pos_type pos, std::ios_base::openmode mode) {
		PHYSFS_seek(file, pos);
		if (mode & std::ios_base::in) {
			setg(egptr(), egptr(), egptr());
		}
		if (mode & std::ios_base::out) {
			setp(buffer, buffer);
		}
		return PHYSFS_tell(file);
	}

uint32_t File::tell() const
{
	check_file_open();

	PHYSFS_sint64 tp = PHYSFS_tell( reinterpret_cast<PHYSFS_file*> (mHandle) );

	if(tp == -1)
		BOOST_THROW_EXCEPTION( PhysfsFileException(mFileName) );

	return tp;
}

long OSBasics::tell(OSFILE * stream) {
	switch(stream->fileType) {
		case OSFILE::TYPE_FILE:
			return ftell(stream->file);
			break;
		case OSFILE::TYPE_ARCHIVE_FILE:
			return PHYSFS_tell(stream->physFSFile);
			break;			
	}
	return 0;
}

static long wz_oggVorbis_tell(void *datasource)
{
	PHYSFS_file* fileHandle;

	ASSERT(datasource != NULL, "NULL decoder passed!");

	fileHandle = ((struct OggVorbisDecoderState*)datasource)->fileHandle;
	ASSERT(fileHandle != NULL, "Bad PhysicsFS file handle passed in");

	return PHYSFS_tell(fileHandle);
}

std::size_t File::CurrentPosition() const
{
   PHYSFS_sint64 position = PHYSFS_tell(impl->physfsFileHandle);

   if (position == -1)
   {
      throw Exception(std::string("Could not obtain current position of file ") + mountedFilePath.path + "\n" + PHYSFS_getLastError());
   }

   return LossyCast<std::size_t, PHYSFS_sint64>(position);
}

	pos_type seekoff(off_type pos, ios_base::seekdir dir, ios_base::openmode mode) {
		switch (dir) {
		case std::ios_base::beg:
			PHYSFS_seek(file, pos);
			break;
		case std::ios_base::cur:
			// subtract characters currently in buffer from seek position
			PHYSFS_seek(file, (PHYSFS_tell(file) + pos) - (egptr() - gptr()));
			break;
		case std::ios_base::end:
			PHYSFS_seek(file, PHYSFS_fileLength(file) + pos);
			break;
		}
		if (mode & std::ios_base::in) {
			setg(egptr(), egptr(), egptr());
		}
		if (mode & std::ios_base::out) {
			setp(buffer, buffer);
		}
		return PHYSFS_tell(file);
	}

bool physfsFile::Seek(Bit32u * pos,Bit32u type) {
	PHYSFS_sint64 mypos = (Bit32s)*pos;
	switch (type) {
	case DOS_SEEK_SET:break;
	case DOS_SEEK_CUR:mypos += PHYSFS_tell(fhandle); break;
	case DOS_SEEK_END:mypos += PHYSFS_fileLength(fhandle); break;
	default:
	//TODO Give some doserrorcode;
		return false;//ERROR
	}

	if (!PHYSFS_seek(fhandle,mypos)) {
		// Out of file range, pretend everythings ok 
		// and move file pointer top end of file... ?! (Black Thorne)
		PHYSFS_seek(fhandle,PHYSFS_fileLength(fhandle));
	};
	//LOG_MSG("Seek to %i (%i at %x) of %s (%s)",(int)mypos,(int)*pos,type,name,PHYSFS_getLastError());

	*pos=(Bit32u)PHYSFS_tell(fhandle);
	return true;
}

static int64_t file_phys_ftell(ALLEGRO_FILE *f)
{
   ALLEGRO_FILE_PHYSFS *fp = cast_stream(f);
   PHYSFS_sint64 n;

   n = PHYSFS_tell(fp->phys);
   if (n < 0) {
      phys_set_errno(fp);
      return -1;
   }

   return n;
}

bool physfsFile::Write(Bit8u * data,Bit16u * size) {
	if ((this->flags & 0xf) == OPEN_READ) { // check if file opened in read-only mode
		DOS_SetError(DOSERR_ACCESS_DENIED);
		return false;
	}
	if (last_action==READ) prepareWrite();
	last_action=WRITE;
	if (*size==0) {
		if (PHYSFS_tell(fhandle) == 0) {
			PHYSFS_close(PHYSFS_openWrite(pname));
            return false;
			//LOG_MSG("Truncate %s (%s)",name,PHYSFS_getLastError());
		} else {
			LOG_MSG("PHYSFS TODO: truncate not yet implemented (%s at %lld)",pname,PHYSFS_tell(fhandle));
			return false;
		}
	} else {
		PHYSFS_sint64 mysize = PHYSFS_write(fhandle,data,1,(PHYSFS_uint32)*size);
		//LOG_MSG("Wrote %i bytes (wanted %i) at %i of %s (%s)",(int)mysize,(int)*size,(int)PHYSFS_tell(fhandle),name,PHYSFS_getLastError());
		*size = (Bit16u)mysize;
		return true;
	}
}

static Sint64 physfsrwops_seek(SDL_RWops *rw, Sint64 offset, int whence)
{
    PHYSFS_file *handle = (PHYSFS_file *) rw->hidden.unknown.data1;
    int pos = 0;

    if (whence == SEEK_SET)
    {
        pos = offset;
    }
    else if (whence == SEEK_CUR)
    {
        int current = PHYSFS_tell(handle);
        if (current == -1)
        {
            SDL_SetError("Can't find position in file: %s",
                          PHYSFS_getLastError());
            return(-1);
        }

        if (offset == 0)  // this is a "tell" call. We're done.
            return( current );

        pos = current + offset;
    }
    else if (whence == SEEK_END)
    {
        int len = PHYSFS_fileLength(handle);
        if (len == -1)
        {
            SDL_SetError("Can't find end of file: %s", PHYSFS_getLastError());
            return(-1);
        }

        pos = len + offset;
    }
    else
    {
        SDL_SetError("Invalid 'whence' parameter.");
        return(-1);
    }

    if (!PHYSFS_seek(handle, pos))
    {
        SDL_SetError("PhysicsFS error: %s", PHYSFS_getLastError());
        return(-1);
    }

    return(pos);
}

/**Gets the current offset from the beginning of the file.
 * \return Offset in bytes from the beginning of the file.*/
long File::Tell( void ){
	long offset;
	offset = static_cast<long>(
#ifdef USE_PHYSICSFS
		PHYSFS_tell( fp )
#else
		ftell(fp)
#endif
		);
	if ( offset == -1 ){
		LogMsg(ERR,"%s: Error using file tell. %s",
			validName.c_str(), PHYSFS_getLastError());
	}
	return offset;
}