RAPI2: The Friend You Never Knew You Had

#pragma once
#include <iomanip>
#include <ctime>
#include <locale>

#define EPOCH_DIFF 0x019DB1DED53E8000LL /* 116444736000000000 nsecs */
#define RATE_DIFF 10000000 /* 100 nsecs */

/// convert from FILETIME to time_t 
time_t FileTimeToUnixTime( const FILETIME& ftime ) 
{
    LARGE_INTEGER ll = { ftime.dwLowDateTime, ftime.dwHighDateTime };
    return ( ll.QuadPart - EPOCH_DIFF ) / RATE_DIFF;
}

/// Get the 64-bit size of the file.
__int64 FileSize( const CE_FIND_DATA& i )
{
    return ( static_cast< __int64 >( i.nFileSizeHigh ) << 32 ) + i.nFileSizeLow;
}

/// ostream iterator formatting for CE_FIND_DATA
template< class _CharT = wchar_t, class _Traits = std::char_traits< _CharT > >
struct WinCeFindData
{
    typedef typename std::basic_ostream< _CharT, _Traits > stream_type;
    typedef WinCeFindData< _CharT, _Traits > _Self;

    WinCeFindData( const CE_FIND_DATA& data ) : data_( data ) {};

    friend stream_type& operator<<( stream_type& os, const _Self& item )
    {
        stream_type::sentry os_lock( os );
        if( !os_lock )
            return os;
        
        // print the creation date/time
        _CharT pattern[] = L"%m/%d/%Y  %I:%M %p  ";
        time_t universal_time = FileTimeToUnixTime( item.data_.ftCreationTime );
        tm local_time = { 0 };
        if( localtime_s( &local_time, &universal_time ) == 0 )
        {
            std::time_put< _CharT > const& time_facet = 
                std::use_facet< std::time_put< _CharT > >( os.getloc() );
            time_facet.put( os, 
                            os, 
                            L' ', 
                            &local_time, 
                            pattern, 
                            pattern + wcslen( pattern ) );
        }
        else
        {
            os << L"00/00/0000  00:00 AM  ";
        }

        os << std::setfill( L' ' );

        // print the file size or <DIR> for directories
        if( item.data_.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
            os << std::left 
               << std::setw( 14 ) 
               << L"<DIR>";
        else
            os << std::right 
               << std::setw( 14 ) 
               << FileSize( item.data_ );

        // print the file name
        os << L" " << item.data_.cFileName;
        return os;
    };

private:
    // local reference to the data being printed
    const CE_FIND_DATA& data_;
    // no assignment
    const _Self& operator=( const _Self& );
}; // struct WinCeFindData

/// determine if a particular item is a directory or not.
bool is_directory( const CE_FIND_DATA& data )
{
    return ( data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY ) != 0;
}

/// return true if i < j
bool descending( const CE_FIND_DATA& i, const CE_FIND_DATA& j )
{
    // we sort directories first, then by filename
    if( is_directory( i ) != is_directory( j ) )
        return is_directory( i );
    return _wcsicmp( i.cFileName, j.cFileName ) < 0;
}

/// add the file size of a CE_FIND_DATA
__int64 operator+( __int64 i, const CE_FIND_DATA& j )
{
    if( !is_directory( j ) )
        i += FileSize( j );
    return i;
}