/**
 * Parses shortcodes in email content with the correct user context.
 *
 * @param string $email_content The email content with shortcodes.
 * @param string $user_email    The email address of the user to simulate context.
 * @return string The parsed and sanitized email content.
 */
function parse_email_shortcodes_with_user_context( $email_content, $user_email ) {

    // Look up the user by email.
    $user = get_user_by( 'email', $user_email );

    if ( ! $user ) {
        return $email_content; // No user found, return unparsed.
    }

    // Backup the current user globals.
    $original_user_id = get_current_user_id();
    $original_user    = $GLOBALS['current_user'] ?? null;

    // Override current user globals.
    wp_set_current_user( $user->ID );
    $GLOBALS['current_user'] = $user;

    // Allow shortcodes to reference current user context.
    $content = do_shortcode( $email_content );

    // Restore original current user.
    wp_set_current_user( $original_user_id );
    $GLOBALS['current_user'] = $original_user;

    // Ensure output is safe for email.
    return wp_kses_post( $content );
}

/**
 * Parses shortcodes in all outgoing emails using user context.
 *
 * @param array $args The email parameters.
 * @return array Modified email parameters.
 */
function myplugin_parse_shortcodes_in_emails( $args ) {

    // Bail if no valid recipient.
    if ( empty( $args['to'] ) || ! is_email( $args['to'] ) ) {
        return $args;
    }

    // Allow multiple recipients (take first only, or enhance for looping).
    $recipient_email = is_array( $args['to'] ) ? $args['to'][0] : $args['to'];

    // Parse the message content using the recipient's user context.
    $args['message'] = parse_email_shortcodes_with_user_context( $args['message'], $recipient_email );

    return $args;
}
add_filter( 'wp_mail', 'myplugin_parse_shortcodes_in_emails' );