Txn ID,  Name ,  Type , Product ID, Qty, Gross
010   ,  Moe  ,  Cart ,           ,  1 ,   15
010   ,  Moe  ,  Item ,  widget-1 ,  1 ,   15
020   ,  Larry,  Cart ,           ,  3 ,   35
020   ,  Larry,  Item ,  widget-1 ,  1 ,   15
020   ,  Larry,  Item ,  widget-2 ,  2 ,   20

##</code><code>##

Txn ID,  Name ,  Qty, Gross, widget-1 Qty, widget-1 Gross, widget-2 Qty, widget-2 Gross
010   ,  Moe  ,  1  , 20   ,   1         , 15            ,             , 
020   ,  Larry,  3  , 35   ,   1         , 15            , 2           ,  20

##</code><code>##

#!/usr/bin/perl
use strict;

use Text::CSV;
use Data::Dumper;

my $report_file = '/files/report.csv';

my $csv_file = '/files/custom.csv';

my $csv = Text::CSV->new ( { allow_whitespace => 1, binary => 1, sep_char => ',' } )
	or die "Cannot use CSV: ".Text::CSV->error_diag ();

my $csv_fh;
open ($csv_fh, "<:encoding(utf8)", $csv_file) or die "$csv_file : $!";
# declare column names for getline_hr
$csv->column_names($csv->getline($csv_fh)) or die "$csv_file : $!";

my @records = ();
my @temp = ();
my %column_order = ();
my $ci= 0;
while (my $row = $csv->getline_hr($csv_fh)) {
	my $key;
	my $value;
	if (${$row}{'Type'} eq 'Shopping Cart Payment Received') {			
	  # push (@records, \@temp) if @temp; EDITED: THIS LINE RESULTED IN OVERWRITTEN DATA
            push (@records, [@temp]) if @temp; # THIS SEEMS TO WORK, SEE MY COMMENT BELOW
		@temp = ();	
		while (($key, $value) = each %{$row}) { 
			${%column_order}{$key} = $ci++ unless (defined ${%column_order}{$key});  
			$temp["${%column_order}{$key}"] = $value;																	
		}
	} elsif (${$row}{'Type'} eq 'Shopping Cart Item') {
		# more code to add append to first row
	)
}

my $report_fh;
open ($report_fh, ">:encoding(utf8)", $report_file) or die "$report_file : $!";

for my $key (sort {$column_order{$a}<=>$column_order{$b}} keys %column_order) {
 print $report_fh "$key" , ", ";
 }
 print $report_fh "\n";
 
for my $record (@records) {
print $report_fh join(", ",@$record), "\n";
 }
 print $report_fh "\n";