
sub tokenizer_header {
	# prende l'header contenuto in $self->{header} e ne estrae i
	# token fondamentali inserendoli in $self->{tokens}
	my $self 		= shift;
	my $header 	= $self->{header};
  $header 		=~m|<head>(.*?)</head>|smi;
	$header			= $1;
	my $p = HTML::TokeParser->new(\$header);
	$self->{tokens} 	= {};
  while (my $token  = $p->get_tag()) {
  	my $tag  = $token->[0];
    my $type = substr($tag,0,1) eq '/' ? 'E' : 'S';
    my $tag_text;
    if ($type eq 'S') {
    	$tag_text = $token->[3];
      my $text = $p->get_text();
      my $struct = [$tag_text,$text,undef];
      push @{$self->{tokens}->{$tag}},$struct;
    } elsif ($type eq 'E') {
      $tag      = substr($tag,1,length($tag)-1);
      $tag_text = $token->[1];
      my $last_idx = scalar @{$self->{tokens}->{$tag}}-1;
      $self->{tokens}->{$tag}->[$last_idx]->[2] = $tag_text;
    }
  }
}