#!/usr/bin/perl

use strict;
use warnings;

# Data
my $p_expected_output = [
    '0601|3|NORM|2|ALLO|XLF753|U|0045|0050|',
    '0603|5|NORM|2|ALLO|ADR2CG||0430|0438|',
    '0604|6|NORM|2|ALLO|AF681VC|i U|0500|0510|',
    '0605|7|NORM|2|ALLO|AF651PQ|i|0515|0523|',
    '0606|8|NORM|2|ALLO|AF713BR|i|0445|0453|',
    '0607|9|NORM|2|ALLO|AFR100M|i|0520|0533|',
    '0609|11|NORM|2|ALLO|GJT775|i E|2300|2315|',
    '0610|12|NORM|2|ALLO|AF661WN|i|0450|0500|0500|',
];


my $p_input = [
    '0601 3      NORM 2  ALLO XLF753         U 0045 0050 ',
    '0603 5      NORM 2  ALLO ADR2CG           0430 0438 ',
    '0604 6      NORM 2  ALLO AF681VC  i     U 0500 0510 ',
    '0605 7      NORM 2  ALLO AF651PQ  i       0515 0523 ',
    '0606 8      NORM 2  ALLO AF713BR  i       0445 0453 ',
    '0607 9      NORM 2  ALLO AFR100M  i       0520 0533 ',
    '0609 11     NORM 2  ALLO GJT775   i E     2300 2315 ',
    '0610 12     NORM 2  ALLO AF661WN  i       0450 0500 0500 ',
];


# Main program
my $p_output = generate_output($p_input);

if (arrays_match($p_output, $p_expected_output)) {
    print "Success!\n";
} else {
    print "Generated output does NOT match expected output :-(\n";
}

##</code><code>##

# Subroutines
sub arrays_match {
    my ($p1, $p2) = @_;
    if (@$p1 != @$p2) {
        return 0;        # Lengths don't match
    }
    for (my $i = 0; $i < @$p1; $i++) {
        if ($p1->[$i] ne $p2->[$i]) {
            # Elements don't match
            printf "Mismatch at line %d:\n", $i + 1;
            printf "  Array1:  '%s'\n", $p1->[$i];
            printf "  Array2:  '%s'\n", $p2->[$i];
            return 0;
        }
    }
    return 1;    # Arrays match
}


sub generate_output {
    my ($parray) = @_;
    my @output = ( );
    foreach my $line (@$parray) {
        push @output, transform_line($line);
    }
    return [ @output ];
}    


sub transform_line {
    my $line = shift;
    $line =~ s/\s+$//;    # Trim trailing whitespace

    # Assume the line is 6 words, followed (optionally) by any
    # combination of { i, E, U } (with optional space around them),
    # followed (optionally) by more words.
    #
    if ($line !~ s/^(\S+)\s+(\S+)\s+(\S+)\s+(\S+)\s+(\S+)\s+(\S+)\s+//) {
        die "Didn't get expected 6 words in line:\n$line\n";
    }
    my $output = join('|', $1, $2, $3, $4, $5, $6);
    if ($line =~ s/((i\s*)?(E\s*)?(U\s*)?)//) {
        # Split on whitespace, and then put the optional { i, E, U }
        # back together, with a single space between each.
        my $optarg = join(' ', split(/\s+/, $1));
        $output .= "|$optarg";
    }
    while ($line =~ s/^\s*(\S+)//) {
        my $word = $1;
        $output .= "|$1";
    }
    $output .= "|";

    return $output;
}