Display total sales on frontend

I’ve added this snippet which works. What would be the easiest way to add a category filter to it?

// function that runs when shortcode is called
function report_total_sales() {
global $wpdb;
    $order_totals = apply_filters( 'woocommerce_reports_sales_overview_order_totals', $wpdb->get_row( "
    SELECT SUM(meta.meta_value) AS total_sales, COUNT(posts.ID) AS total_orders FROM {$wpdb->posts} AS posts
    LEFT JOIN {$wpdb->postmeta} AS meta ON posts.ID = meta.post_id
    WHERE meta.meta_key = '_order_total'
    AND posts.post_type = 'shop_order'
    AND posts.post_status IN ( '" . implode( "','", array( 'wc-completed', 'wc-processing', 'wc-on-hold' ) ) . "' )
    " ) );
    return absint( $order_totals->total_sales);
} 
// register shortcode
add_shortcode('total_sales', 'report_total_sales');