Custom login doesn’t work properly

Here is my working solution:

function custom_login() {
    if(!empty($_POST['user_login']) && !empty($_POST['user_pass'])){
        $login_data = array();
        $login_data['user_login'] = sanitize_user($_POST['user_login']);
        $login_data['user_password'] = esc_attr($_POST['user_pass']);
        $login_data['rememberme'] = true;
        $nonce = $_REQUEST['_wpnonce'];

        $user = wp_signon( $login_data, false );

        global $user_ID;
        // Check whether the user is already logged in and the nonce is verified
        if ( !$user_ID && !wp_verify_nonce( $nonce, 'wp_login' ) ) {
            exit;
        } else {
            if ( is_wp_error($user) ) {
                echo $user->get_error_message();
            } else {
                wp_clear_auth_cookie();
                do_action('wp_login', $user->ID);
                wp_set_current_user($user->ID);
                wp_set_auth_cookie($user->ID, true);
                wp_safe_redirect(home_url());
                exit;
            }
        }
    }
}