use 5.38.0;

package Part2;

use Part1;

use List::AllUtils qw/all first_index none min max /;

sub get_cycle( $current, $directions, $nodes ) {

    my @tracks;
    my $next_index = 0;

    while() {
    use DDP; #p @tracks;
        my $t = join '-',  $current,$next_index;
        my $i = first_index { $_ eq $t } @tracks;
        if( $i > -1 ) {
            my $c = 0;
            #   p @tracks;
            # warn $i, " ",$t;
            return $i, map {
                $c++;
                if(/Z-/) {
                    my $x = $c; $c = 0; $x;
                }else {
                    ()
                }
            } splice @tracks, $i;
        }
        push @tracks, $t;
        $current = $nodes->{$current}[ $directions->[ $next_index ] ];
        $next_index = ( $next_index+1)% @$directions;
    }


}

sub find_z($current,$next_index,$directions,$nodes) {

    my $visited    = 0;

    while ( ) {
        $visited++;

        $current =
          $nodes->{$current}[ $directions->[ $next_index++ % @$directions ] ];

        last if $current =~ /Z$/ 
    }

    return $visited, $current, $next_index;
}
sub speedrun($current,$next_index,$directions,$nodes,$n) {

        $current =
          $nodes->{$current}[ $directions->[ $next_index++ % @$directions ] ]
            for 1..$n;

    return $current;
}

sub solution_2 ($input) {
    my $p          = Part1::parse_input($input);
    my @directions = $p->{directions}->@*;
    my %nodes      = $p->{nodes}->%*;

    my $steps = 0;
    my @paths = grep { /A$/ } keys %nodes;
    my $next_index = 0;

    until( all {/Z$/ } @paths ) {
        my($incr,$current,$new_index) = find_z($paths[0],$next_index,\@directions,\%nodes);
        $paths[0] = $current;
        @paths = ( $current, map {
                speedrun($paths[$_],$next_index,\@directions,\%nodes,$incr)
            } 1..$#paths );
        $next_index = $new_index;
        $steps += $incr;
    }


    return $steps;


}

1;