using System.Data;
using System.Threading;
using System.Threading.Tasks;

namespace GB5Shared.FileImport
{
    public interface IFileToDataTableService
    {
        // Reads an Excel or CSV file from disk and returns its content as a DataTable.
        // All columns are string. DATE columns are converted to "dd-MMM-yyyy".
        Task<DataTable> ReadAsync(
            string filePath,
            ImportFileTypeEnum fileType,
            CancellationToken ct = default);

        // Reads an Excel or CSV file from raw bytes (decoded from Base64 by the caller).
        // Use this instead of ReadAsync when the file content arrives over the wire.
        Task<DataTable> ReadFromBytesAsync(
            byte[] bytes,
            ImportFileTypeEnum fileType,
            CancellationToken ct = default);
    }
}