Duetro's submission - Skript Challenge (Deobfuskator 1.0))

function script_looksvalid($code) {
    $code = str_replace("\t", ' ', $code);
    $keywords = [' set ', ' add ', 'command ', ' trigger:', ' else', ' if ', ' send ', ' message ', 'every ', 'loop ', ' player ', ' to ', 'on '];

    foreach ($keywords as $word) {
        if (stripos($code, $word) !== false) {
            return true;
        }
    }
    return false;
}

function deobfuscate($code) {
    $read = false;
    $options = null;
    $code = str_replace("\r", null, $code);

    foreach (explode(PHP_EOL, $code) as $line) {
        if (($line == 'options:') && ($read == false)) {
            $read = true;
            $code = str_replace($line, null, $code);

        } else if ($read == true) {
            if ((strpos($line, ' ') === 0) || (strpos($line, "\t") === 0)) {
                $option = explode(': ', trim($line), 2);
                $options['{@' . $option[0] . '}'] = $option[1];
                $code = str_replace($line.PHP_EOL, '', $code);

            } else {
                $read = false;

            }
        }
    }
    if (is_array($options)) {
        $temp_keys = array_map('strlen', array_keys($options));
        array_multisort($temp_keys, SORT_DESC, $options);
        $code = str_replace(array_keys($options), array_values($options), $code);

        if (!script_looksvalid($code)) {
            $notice['warning'] = 'This code doesn\'t look like valid script code. Are you sure this is a script that has been obfuscated using <b>Deobfuskator</b>?';
        }
    } else {
        $notice['error'] = 'Oops! Something went wrong while reading the file. Are you sure that this is a script that has been obfuscated using <b>Deobfuskator</b>? (ERR1)';
    }
}