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

namespace PayRollBLL.SAP.Client
{
    public interface ISapApiClient
    {
        /// <summary>
        /// Fetches a fresh SAP CSRF token, then POSTs <paramref name="jsonPayload"/>
        /// to <paramref name="endpointPath"/>.
        ///
        /// Before the HTTP call, the host reachability is verified (TCP connection test).
        /// The SAP response is parsed for business-level messages; only SAP's own message
        /// text is surfaced — this method never invents its own business error text.
        ///
        /// Never throws on HTTP/network failures — all outcomes are captured in the returned DTO.
        /// </summary>
        /// <param name="endpointPath">
        /// OData entity-set path, e.g.
        /// "/sap/opu/odata/sap/ZPY_ITDEC_PREVIOUS_SRV/ITDecPreviousHeaderSet".
        /// </param>
        /// <param name="msgNavProperty">
        /// Navigation property name that carries SAP messages in the response body,
        /// e.g. "NAV2ITDECPREVMSG". Pass empty string if unknown (skips message parsing).
        /// </param>
        /// <param name="jsonPayload">Serialized SAP payload to POST.</param>
        Task<SapApiResultDTO> PostAsync(
            string endpointPath,
            string msgNavProperty,
            string jsonPayload,
            CancellationToken ct);
    }

    /// <param name="IsSuccess">True when SAP confirmed the data was posted without business errors.</param>
    /// <param name="StatusCode">HTTP status code returned by SAP (0 = network failure before HTTP).</param>
    /// <param name="ResponseBody">Raw response body from SAP, empty on network failure.</param>
    /// <param name="Message">
    /// User-facing message.
    /// On success: "IT Declaration data posted to SAP successfully."
    /// On SAP business error: SAP's exact error text.
    /// On network/config error: descriptive reason (DNS, port, TLS, timeout).
    /// </param>
    public record SapApiResultDTO(
        bool   IsSuccess,
        int    StatusCode,
        string ResponseBody,
        string Message);
}