#!/usr/bin/perl
#
# Bulk of the load credited to tybalt89 on irc.perl.org
#
use strict;
use Getopt::Std;


my @words;
my $given;
my @matches;
my %sizes;
my %opt;
my $wordlist = "/usr/share/dict/words";

getopts('c:s:e:w:a:', \%opt);

if (!$opt{'c'}) {
  print "Usage: $0 -c <chars> [-s <start chars>] [-e <end chars>] [-w <path to wordlist>] [-a <anywhere chars>]\n";
  exit;
}
if ($opt{'w'}) {
  $wordlist = $opt{'w'};
}

open(my $WL_FP, $wordlist) || die "Could not open wordlist \"$wordlist\": $!\n";
@words = <$WL_FP>;
close($WL_FP);
map (s/[\r\n]$//, @words);

$given = $opt{'c'};
if ($opt{'s'}) { $given .= $opt{'s'}; }
if ($opt{'e'}) { $given .= $opt{'e'}; }
if ($opt{'a'}) { $given .= $opt{'a'}; }

$given = join '', sort split //, $given;

foreach my $word (@words) {
  if ($opt{'a'} && $word !~ /$opt{'a'}/) { next; }
  if ($opt{'s'} && $word !~ /^$opt{'s'}/) { next; }
  if ($opt{'e'} && $word !~ /$opt{'e'}$/) { next; }

  my $pat = join '.*', sort split //, $word;

  if ($given =~ $pat) {
    my $word_len = length($word);
    if ($word_len < 2) { next; }
    if (!defined $sizes{$word_len}) {
      my @tmp;
      $sizes{$word_len} = \@tmp;
    }
    push @{$sizes{$word_len}}, $word;
  }
}

foreach my $size (sort keys %sizes) {
  print "$size: " . join(', ',@{$sizes{$size}}) . "\n" ;
}