# hl7_conv

use strict;
use warnings;

my $input = q(AB\T\F\S\CD\E\E\E\R\R\R);
my $gen_out = '';
my $exp_out = q(AB&F^CD\\E\\R~R);

my %convs = (
    E   => '\\',
    F   => '|',
    R   => '~',
    S   => '^',
    T   => '&',
);

$gen_out = hl7_replace($input);

print "INPUT:   $input\n";
print "GEN_OUT: $gen_out\n";
print "EXP_OUT: $exp_out\n";

print $0, ': ', $gen_out eq $exp_out ? 'SUCCESS!' : '  Z z . c8o,  ', "\n";

exit 0;

sub hl7_replace
{
    my $in = shift;

    my @input = split //, $in;
    my @output = ();

    for (my $i = 0; $i <= $#input; ++$i)
    {
        if ($input[$i] eq "\\" && ($i + 2) <= $#input 
            && $convs{$input[$i + 1]} && $input[$i + 2] eq "\\")
        {
            push @output, $convs{$input[$i + 1]};
            $i += 2;
        }
        else
        {
            push @output, $input[$i];
        }
    }

    return join '', @output;
}