Wordpress - redirect in functions.php

[aizu]

add_action('template_redirect', 'redirect_old_domain');

function redirect_old_domain() {
    $old_domain = 'domain.org';
    $new_domain = 'domain.com';

    if ($_SERVER['HTTP_HOST'] == $old_domain && $request_uri == '/') {
        // Redirect to the new domain without any path
        $redirect_url = 'https://' . $new_domain;

        wp_redirect($redirect_url, 302); // 302: Temporary redirect
        exit;
    }

    // Check if the request is for a specific year
    preg_match('/\/(\d{4})\//', $request_uri, $matches);
    $year = isset($matches[1]) ? $matches[1] : '';
    
    if ($year) {
        // Redirect to the same URI on the new domain
        $redirect_url = 'https://' . $new_domain . '/' . $year . $request_uri;
    
        wp_redirect($redirect_url, 302); // 302: Temporary redirect
        exit;
    }
}