advent day 4b solution

$input = file_get_contents("4.txt");
$passports = explode("\n\n", $input);
$valid = 0;

$sections = [
    'byr' => function($data){ return strlen($data) == 4 && $data >= 1920 && $data <= 2002; },
    'iyr' => function($data){ return strlen($data) == 4 && $data >= 2010 && $data <= 2020; },
    'eyr' => function($data){ return strlen($data) == 4 && $data >= 2020 && $data <= 2030; },
    'hgt' => function($data){ $unit = substr($data,strlen($data)-2,2); return ($unit == "in" && intval($data) >= 59 && intval($data) <= 76) || ($unit == "cm" && intval($data) >= 150 && intval($data) <= 193); },
    'hcl' => function($data){ return preg_match("/^#[0-9a-f]{6}$/", $data); },
    'ecl' => function($data){ return in_array($data, ['amb','blu','brn','gry','grn','hzl','oth']); },
    'pid' => function($data){ return preg_match("/^[0-9]{9}$/", $data); },
];

foreach ($passports as $passport) {
    // sneaky dirty PHP way of doing it - convert "byr:1980 hgt:160cm" to "byr=1980&hgt=160cm, then parse it into an array
    $line = str_replace([" ", "\n",":"], ["&","&","="], $passport);
    parse_str($line, $attrs);

    // normal way of doing it
    //$line = str_replace("\n", " ", $passport);
    //$attrs = explode(" ", $line);

    $valid++;
    foreach ($sections as $section => $validatefunc) {
        if ($attrs[$section] == null || !$validatefunc($attrs[$section])) {
            $valid--;
            break;
        }
    }
}

echo $valid;