odjave.pl

#!/usr/bin/perl
use warnings;
use strict;
use utf8;
use File::Basename;

my $filename = $ARGV[0];
open(my $odjave, '< :encoding(UTF-8)', $filename) or die $!;
local $/ = undef;
my $whole_odjave = <$odjave>;
(my $file, my $dir, my $ext) = fileparse($filename, qr/\.[^.]*/);

my @text = split(/Importance*.*/, $whole_odjave); # split into header chunks
my %ODJAVE = ();
foreach (@text) {
    next unless length;
    my $header = $_;
    my $subject;
    my $sender;
    if ($_ =~ m/Subject*.*/) {
        $subject = substr($&, 9);
        $subject =~ s/\+/ /g;
    }
    if ($_ =~ m/SentRepresentingEmailAddress*.*/) {
        $sender = substr($&, 30);
    }
    if ($subject && $sender) {
        if (exists $ODJAVE{$subject}) {
            push($ODJAVE{$subject}, $sender);
        }
        else {
            $ODJAVE{$subject} = [$sender];
        }
    }
}

foreach my $key (keys %ODJAVE) {
    my $out_string = '';
    foreach (@{$ODJAVE{$key}}) {
        $out_string .= "'$_',";
    }
    chop($out_string); # remove last comma
    open(my $out, '>', "$file - $key$ext") or die $!;
    print $out $out_string;
    close($out);
}


close($odjave);
exit();