#!/usr/bin/perl

my $err = 0;

foreach my $fn (@ARGV) {
    open my $fh, "<", $fn or die "$!: $fn";
    my $noblank = 1;
    my $imports = undef;
    while(defined ($_ = <$fh>)) {
        /\s+\n$/ and $err++, print "$fn:$.: Trailing whitespace\n";
        $err++, print "$fn:$.: Extra blank line\n" if !/\S/ && $noblank;
        $noblank = scalar !/\S/;
        if (defined $imports) {
            if (!/^import /) {
                 $err++, print "$fn:$.: nonsorted imports\n" if  join('', sort @$imports) ne join('', @$imports);
                 $imports = undef;
            }
        }
        push @$imports, $_ if /^import /;
    }
    $err++, print "$fn:$. Extra blank line\n" if $noblank;
    close $fh;
}


exit 1 if $err;