#!/usr/bin/env perl

use strict;
use warnings;

use Text::CSV;

my @transform = (
    sub { $_[0] },
    sub { "layernumber $_[0]" },
    sub { 'datatype ' . join ' datatype ', split /,/, $_[0] },
    sub { length $_[0] ? "text $_[0]" : "\b" },
);

my $csv = Text::CSV::->new;

while (my $row = $csv->getline(\*DATA)) {
    $row->[$_] = $transform[$_]->($row->[$_]) for 0 .. $#$row;
    local $\ = eof ? ";\n" : ",\n";
    print "@$row";
}

__DATA__
NPLUS,32,0,
NW,41,0,1
NWER,51,"0,1,2",12

##</code><code>##

$ pm_1175217_csv_transform.pl
NPLUS layernumber 32 datatype 0,
NW layernumber 41 datatype 0 text 1,
NWER layernumber 51 datatype 0 datatype 1 datatype 2 text 12;
$