using ComplianceDAL.DTO.GSTEWayBill;
using ComplianceDAL.Query.GSTEWayBill;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.QueryExecutor;
using Microsoft.Extensions.Logging;

namespace ComplianceDAL.CustomCode.GSTEWayBill;

// Faithful port of GB4's EWayDAL.EwayBillOffline (header/detail build + mainHsnCode resolution),
// minus the ClearTax-specific branch, per explicit instruction. Independent of the E-Invoice
// canonical builder — CanonicalBuilderDAL/QB are neither referenced nor modified here.
public class EWayBillPayloadBuilderDAL : IEWayBillPayloadBuilderDAL
{
    private readonly IQueryExecutor _queryExecutor;
    private readonly ILogger<EWayBillPayloadBuilderDAL> _logger;

    public EWayBillPayloadBuilderDAL(IQueryExecutor queryExecutor, ILogger<EWayBillPayloadBuilderDAL> logger)
    {
        _queryExecutor = queryExecutor;
        _logger        = logger;
    }

    public async Task<EwayBillOffLineDTO?> BuildEwayBillOffLineAsync(int documentId, LoginDTO login, CancellationToken ct)
    {
        try
        {
            var billList = await _queryExecutor.QuerySingleAsync<EwayBillList>(
                login,
                EWayBillPayloadQB.GET_EWAY_HEADER,
                new { DocumentId = documentId, ClientId = login.ClientId },
                cancellationToken: ct).ConfigureAwait(false);

            if (billList is null) return null;

            billList.actualFromStateCode = billList.fromStateCode;
            billList.actualToStateCode   = billList.toStateCode;
            billList.vehicleType         = "R";

            var itemList = await _queryExecutor.QueryAsync<EwayBillItemList>(
                login,
                EWayBillPayloadQB.GET_EWAY_DETAIL,
                new { DocumentId = documentId },
                cancellationToken: ct).ConfigureAwait(false);

            billList.itemList = itemList.OrderBy(i => i.itemNo).ToList();

            if (billList.itemList.Count > 0)
            {
                if (billList.subSupplyType == 4)
                {
                    await ResolveMainHsnCodeForJobWorkAsync(documentId, billList, login, ct).ConfigureAwait(false);
                }
                else
                {
                    billList.mainHsnCode = billList.itemList[^1].hsnCode;
                }
            }

            return new EwayBillOffLineDTO { billLists = [billList] };
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "E-Way Bill payload DAL: BuildEwayBillOffLineAsync failed for DocumentId {DocumentId}", documentId);
            throw;
        }
    }

    // subSupplyType == 4 (Job Work) resolves mainHsnCode from the linked MDUTYTARIFF process record
    // instead of the last line's HSN — matches GB4's SacResult / GET_BIZ_CLASS_FOR_DOC fallback exactly.
    private async Task ResolveMainHsnCodeForJobWorkAsync(int documentId, EwayBillList billList, LoginDTO login, CancellationToken ct)
    {
        var sacCodes = await _queryExecutor.QueryAsync<string>(
            login,
            EWayBillPayloadQB.GET_EWAY_SAC_CODE,
            new { DocumentId = documentId },
            cancellationToken: ct).ConfigureAwait(false);

        var sacCode = sacCodes.FirstOrDefault();
        if (string.IsNullOrEmpty(sacCode))
        {
            var bizClassCount = await _queryExecutor.ExecuteScalarAsync<int>(
                login,
                EWayBillPayloadQB.GET_BIZ_CLASS_FOR_DOC,
                new { DocumentId = documentId },
                cancellationToken: ct).ConfigureAwait(false);

            if (bizClassCount != 1)
                throw new InvalidOperationException("No MMdetailProcess is linked..");
            // Miscellaneous Delivery Challan — process not needed, mainHsnCode stays 0 (matches GB4).
        }
        else
        {
            if (!int.TryParse(sacCode, out var parsedHsn))
                throw new InvalidOperationException("Pl check HSN code linked to MMdetailProcess ,ProcessId");
            billList.mainHsnCode = parsedHsn;
        }
    }
}