<?php
$input = str_split(file_get_contents('input.txt'));

$x = 100;
$y = 100;

$ymax = $y * 2;

$current = $previous = $x + $y * $ymax;

$dists = array_fill(0, $current * 2, 0);

$pos = array();
$directions = array('N' => -$ymax, 'S' => $ymax, 'W' => -1, 'E' => 1);

array_shift($input); //Remove ^
array_pop($input); //Remove $

foreach ($input as $i) {
    switch ($i) {
        case '|':
            $p = end($pos);
            $current = $p;
            break;
        case '(':
            $pos[] = $current;
            break;
        case ')':
            $p = array_pop($pos);
            $current = $p;
            break;
        default:
            $dir = $directions[$i];
            $current += $dir;

            $dc = $dists[$current];
            $dp = $dists[$previous];

            if ($dc === 0) {
                $dists[$current] = $dp + 1;
            } else {
                $dists[$current] = $dc > $dp ? $dp + 1 : $dc;
            }
    }
    $previous = $current;
}

printf('Part 1: %d', max($dists));
echo PHP_EOL;
printf('Part 2: %d', count(array_filter($dists, function ($n) {
    return $n >= 1000;
})));
echo PHP_EOL;