protected DataSet GetData(int sellerId)
        {
            // Harusnya munculin cuma show yang dijual sama si seller
            List <Show> shows   = ShowController.GetShowBySellerId(sellerId);
            DataSet     dataset = new DataSet();

            var dataset_shows = dataset.Show;
            var dataset_transaction_headers = dataset.TransactionHeader;
            var dataset_transaction_details = dataset.TransactionDetail;
            var dataset_users = dataset.User;

            foreach (var show in shows)
            {
                var newShowRow = dataset_shows.NewRow();
                newShowRow["Id"]   = show.Id;
                newShowRow["Name"] = show.Name;
                dataset_shows.Rows.Add(newShowRow);

                List <TransactionHeader> headers = TransactionController.GetAllTransactionHeaderByShowId(show.Id);

                foreach (var header in headers)
                {
                    var newHeaderRow = dataset_transaction_headers.NewRow();
                    newHeaderRow["ShowId"]    = header.ShowId;
                    newHeaderRow["BuyerId"]   = header.BuyerId;
                    newHeaderRow["CreatedAt"] = header.CreatedAt;

                    List <TransactionDetail> details = TransactionController.GetAllTransactionDetailById(header.Id);

                    newHeaderRow["Quantity"] = details.Count;
                    newShowRow["Price"]      = show.Price * details.Count;

                    User user = UserController.GetUserById(header.BuyerId);

                    newHeaderRow["BuyerName"] = user.Name;

                    dataset_transaction_headers.Rows.Add(newHeaderRow);
                }
            }

            return(dataset);
        }