add_action( 'woocommerce_product_options_lottery', 'custom_woocommerce_product_options_lottery', 20);

function custom_woocommerce_product_options_lottery(){
	woocommerce_wp_textarea_input(
					array(
						'id'                => '_lottery_custom_ticket_names',
						'wrapper_class'     => '',
						'description'       => __( 'Enter ticket names separated with ","', 'wc-lottery-pn' ),
						'label'             => __( 'Ticket names', 'wc_lottery' ),
						'desc_tip'          => 'false',
					)
				);
}

add_action( 'lottery_product_save_data' , 'custom_lottery_product_save_data' , 10, 2 );
function custom_lottery_product_save_data( $post_id, $post  ){

	if ( isset( $_POST['_lottery_custom_ticket_names'] ) && ! empty( $_POST['_lottery_custom_ticket_names'] ) ) {
		update_post_meta( $post_id, '_lottery_custom_ticket_names', $_POST['_lottery_custom_ticket_names'] );
	} else {
		delete_post_meta( $post_id, '_lottery_custom_ticket_names' );
	}
}


add_filter( 'change_ticket_numbers_to_alphabet', 'custom_ticket_number_display_html', 1, 3);

function custom_ticket_number_display_html( $ticket_number, $_ticket_number, $product ){
	$lottery_custom_ticket_names = get_post_meta( $product->get_id(), '_lottery_custom_ticket_names', true );
	$names_array  = explode(',', $lottery_custom_ticket_names);
	if ( isset( $names_array[ intval($_ticket_number ) -1 ] ) ){
		return trim( $names_array[ intval($_ticket_number ) -1 ] );
	}
	return $ticket_number;
}