use warnings;
use strict;
use Test;


my ($linecount, $current_col, $tab) = (0, 0, 4);

sub pr {
    for my $string (@_){
        print $string;
        my $lines += () = $string =~ /[\n\r]/g;
        $current_col = 0 if $lines;
        $linecount += $lines;
        $string =~ s/.*[\n\r](.*)$/$1/sg;
        $string =~ s/\t/' ' x $tab/eg;
        my $bs = $string =~ tr/\b//;
        my $bell = $string =~ tr/\a//;
        $current_col += (length $string) - $bs * 2 - $bell;
        $current_col = 0 if $current_col < 0;
        $linecount += int($current_col / 80);
        $current_col %= 80;
    }    
}

BEGIN { plan tests => 24 };

my @tests = (
["1234567890", 0, 10],
["12345\n67890", 1, 5],
["12345\n67890\n12345", 2, 5],
["12345\r67890", 1, 5],
["12345\r67890\r12345", 2, 5],
["12345\t67890", 0, 10 + $tab],
["1234567890\b\b\b\b\b", 0, 5],
[qw/1234567890 1234567890 1234567890 1234567890 1234567890/, 0, 50],
["1234567890" x 10, 1, 20],
["1234567890" x 100, 12, 40],
["1234567890" x 100, "\b" x 50, 12, 0],
["1\b2\b3\b4\b5\b6\b7\b8\b9\b0\b\n12345\t67890\n\t12345\b\b\b\b\b67890\t", 2, 5 + $tab*2],
["1234567890\a\b\a\b\a\b", 0, 7],
);

for my $test (@tests){
    ( $linecount, $current_col ) = ( 0, 0 );
    my @strings = @$test;
    splice @strings, -2, 2, '';
    pr $_ for @strings;
    print "<--\n";
    ok($linecount, $test->[-2], "Linecount incorrect");
    ok($current_col, $test->[-1], "Column count incorrect");
}