Import user memberships

/**
 * This is a code snippet to import user membership data for both expirable and non-expiring
 * memberships for use with the "Import and export users and customers" plugin.
 * @link https://wordpress.org/plugins/import-users-from-csv-with-meta/
 *
 * In your CSV import file, add a column for each membership as follows:
 * "_wpmem_products_" + "membership-slug". 
 * (Get the slug from Memberships > All memberships)
 *
 * Example: if the membership slug is "my-simple-membership", then the column heading is:
 * "_wpmem_products_my-simple-membership".
 *
 * If the membership is a non-expiration membership, values are 1 for enabled, 0 for disabled
 * If the membership is an expiration membership, the expiration date MUST be YYYY-MM-DD. Any
 * other date format will not be read correctly and will cause an error.
 *
 * The script will adjust dates to the proper timestamp format and update the user's
 * membership array.
 */
 add_action( 'post_acui_import_single_user', function( $headers, $data, $user_id ) {

    $memberships = wpmem_get_memberships();

    foreach ( $headers as $i => $header ) {
        $membership_meta = substr( $header, 16 );
        if ( array_key_exists( $membership_meta, $memberships ) ) {
            if ( 0 != $data[ $i ] ) {
                $expiration_period = ( isset( $memberships[ $membership_meta ]['expires'] ) ) ? $memberships[ $membership_meta ]['expires'] : false;
                $date = ( $expiration_period ) ? $data[ $i ] : false;
                wpmem_set_user_product( $membership_meta, $user_id, $date );
            } else {
                wpmem_remove_user_product( $membership_meta, $user_id );
            }
        }
    }
    
}, 10, 3);