# From: x920031@rubb.rz.ruhr-uni-bochum.de (Jost Krieger)
#
# Now here is my file cyber.pl, accessed via external_mapping=cyber.pl.
# Problems are: I get "malformed cmd-links" for each access to the file.
#For the first access I get one malformed cmd-link for the tempname kludge
#(well deserved), and for any further access in the same run, I get one
#malformed ... for each subroutine. It works, though.
#
#Remark: this is for a filesystems where filenames are restricted to
#31 chars *after* some funny remapping.
#
#=========================================================================

#override filename (very unclean)

sub filename_to_tempname
{
	local( $dir, $file ) = @_;

	# dir 
	return "$dir.$file.";
}

package extmap;

# constant for cyber file name length
$cyber_length_max = 29;		# leave room for temp name letters ...


sub map {
	local($dest_path) = @_;
	local($dest_file,@new_path);
	local(@old_path)=split("/",$dest_path);
	for $dest_file (@old_path) {
	   if(&cyber_length($dest_file)>$cyber_length_max) {
	       $dest_file = &cyber_length_trim($dest_file,$cyber_length_max);
	   }
           push(@new_path, $dest_file);
	}
        $dest_path=join("/",@new_path);
	return $dest_path;
}


# cut name length for cyber
sub cyber_length_trim {
    local ($unix_name, $max_name) = @_;
    local ($postfix); 
    local($toomuch)=&cyber_length($unix_name)-$max_name; 

    $unix_name = reverse($unix_name);
#	print $unix_name,$toomuch,"\n";

    if( $unix_name =~ s/^(..?.?\.)//) {
        $postfix = $1;
    }

    if ($toomuch>0) {
        $unix_name =~ tr/A-Z/a-z/;
        $toomuch = &cyber_length(reverse($postfix . $unix_name))-$max_name; 
    }
#	print $unix_name,$toomuch,"\n";

    while($toomuch>0) {
        last unless ($unix_name =~ s/[aeiou]// > 0);
        $toomuch -= 1;
    }
#	print $unix_name,$toomuch,"\n";

    if ($toomuch > 0) {
        $unix_name = substr($unix_name, $toomuch);
    }
#	print $unix_name,$toomuch,"\n";

    $unix_name = reverse($postfix . $unix_name);
}

# file name length on cyber
sub cyber_length {
    local ($unix_name) = @_;
    local ($length) = 0;
    
    $length +=1 if $unix_name =~ /^[0-9]/;
#	print $unix_name,$length,"\n";
    $length -=1 if $unix_name =~ /[A-Z]$/;
#	print $unix_name,$length,"\n";
    $length += 3* ($unix_name =~ tr/A-Za-z0-9$._][-//cd);
#	print $unix_name,$length,"\n";
    $length += 2* ($unix_name =~ tr/-][//d);
#	print $unix_name,$length,"\n";
    $length += ($unix_name =~ tr/0-9$._//d);
#	print $unix_name,$length,"\n";
    $length += ($unix_name =~ tr/A-Z/A/s);
#	print $unix_name,$length,"\n";
    $length += 2*($unix_name =~ tr/A-Z//d);
#	print $unix_name,$length,"\n";
    $length += length($unix_name);
#	print $unix_name,$length,"\n";
    $length;
}

#=========================================================================
#
#--
#Jost Krieger, Rechenzentrum der Ruhr-Universitaet Bochum
#x920031@rubb.rz.ruhr-uni-bochum.de
#g=Jost;s=Krieger;ou=ruba;ou=rz;pd=ruhr-uni-bochum;ad=dbp;c=de