#!/data/data/com.termux/files/usr/bin/perl
use strict;
use warnings;
use File::Spec;
use File::Path qw(make_path);
use Digest::MD5;
use File::Copy qw(move);
use feature 'say';
use File::Basename;

my $src = shift @ARGV or die "Usage: $0 dir\n";
die "'$src' is not readable" unless -d $src and -r $src;
my $dup_dir = File::Spec->catdir($src, "copies");
make_path($dup_dir) unless -d $dup_dir;
opendir(my $d, $src) or die $!;
my @unsorted_stuff = grep { -f File::Spec->catfile($src, $_) } readdir($d);
closedir($d);

my %fried;
map {
    my $file = $_;
    my $path = File::Spec->catfile($src, $file);
    open(my $potato, '<', $path) or warn "I couldn't open '$file'\n";
    binmode($potato);
    my $hash = Digest::MD5->new->addfile($potato)->hexdigest;
    close($potato);
    if ($fried{$hash}) {
        my $dest = File::Spec->catfile($dup_dir, $file);
        my $i = 1;
        my ($name,$dir,$ext) = fileparse($file, qr/\.[^.]*/);
        $dest = File::Spec->catfile($dup_dir, "${name}_$i$ext") while -e $dest and $i++;
        move($path, $dest) or warn $!;
        say "Duplicate $file is moved to $dest";
    } else {
        $fried{$hash} = 1;
    }
} @unsorted_stuff;
say "All copies in $src have been moved to $dup_dir!";