#!/usr/bin/perl
use strict;
use warnings;
use Storable;
use Text::LevenshteinXS 'distance';

my @word;
open(my $fh, '<', 'four_dict.txt') or die $!;
while (<$fh>) {
    tr/\r\n//d;
    push @word, $_;
}

my %dict;

for my $i (0 .. $#word - 1) {
    my $i_score = score($word[$i]);
    for my $j ($i + 1 .. $#word) {
        if (distance($word[$i], $word[$j]) == 1) {
            my $j_score = score($word[$i]);
            $_ = $word[$i] ^ $word[$j];
            /[^\0]/;
            my $pos = $-[0];
            my $i_let = substr($word[$i], $pos, 1);
            my $j_let = substr($word[$j], $pos, 1);
            push @{$dict{$word[$i]}}, {word => $word[$j], score => $j_score, letter => $j_let, position => $pos};
            push @{$dict{$word[$j]}}, {word => $word[$i], score => $i_score, letter => $i_let, position => $pos};
        }
    }
}
store \%dict, 'word_list.db';
sub score {
    my ($word) = @_;
    my %point = (
        A => 10, B => 40, C => 40, D => 30,  E => 10, F => 50, G => 40, H => 40, I => 20, J => 80, K => 40, L => 20, M => 30,
        N => 20, O => 10, P => 30, Q => 100, R => 20, S => 10, T => 20, U => 20, V => 60, W => 80, X => 90, Y => 40, Z => 80
    );
    my $score = 0;
    for (split //, $word) {
        $_ = uc($_);
        $score += $point{$_};
    }
    return $score;
}