AyeCode / invoicing

function wpinv_update_item( $args = array(), $wp_error = false ) {

    $item = !empty( $args['ID'] ) ? new WPInv_Item( $args['ID'] ) : NULL;

    if ( empty( $item ) || !( !empty( $item->post_type ) && $item->post_type == 'wpi_item' ) ) {

        if ( $wp_error ) {

            return new WP_Error( 'wpinv_invalid_item', __( 'Invalid item.', 'invoicing' ) );

        }

        return 0;

    }

    if ( !empty( $args['custom_id'] ) ) {

        $item_exists = wpinv_get_item_by( 'custom_id', $args['custom_id'], ( !empty( $args['type'] ) ? $args['type'] : $item->type ) );

    if ( !empty( $args['custom_id'] ) ) {

        $item_exists = wpinv_get_item_by( 'custom_id', $args['custom_id'], ( !empty( $args['type'] ) ? $args['type'] : $item->type ) );

        if ( !empty( $item_exists ) && $item_exists->ID != $args['ID'] ) {

            if ( $wp_error ) {

                return new WP_Error( 'wpinv_invalid_custom_id', __( 'Item with custom id already exists.', 'invoicing' ) );

            }

            return 0;

        }

    }

    $meta_fields = array( 'type', 'custom_id', 'custom_singular_name', 'custom_name', 'price', 'editable', 'vat_rule', 'vat_class', 'is_recurring', 'recurring_period', 'recurring_interval', 'recurring_limit', 'free_trial', 'trial_period', 'trial_interval' );