using System.Text.Json;
using FLSBLL.Session;
using FLSDAL.CustomCode.Survey;
using FLSDAL.DTO.Session;
using FLSDAL.DTO.Survey;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.GenerateAutoNumber;
using GB5Shared.Resource.Response;
using GB5Shared.Telemetry;
using Microsoft.Extensions.Logging;

namespace FLSBLL.Survey;

public class SurveyAnswerBLL : ISurveyAnswerBLL
{
    private readonly ISurveyAnswerDAL   _answerDal;
    private readonly ISurveySummaryDAL  _summaryDal;
    private readonly ISurveySummaryBLL  _summaryBll;
    private readonly IFlsSessionBLL     _sessionBll;
    private readonly AutoNumber         _autoNumber;
    private readonly ILogger<SurveyAnswerBLL> _logger;

    public SurveyAnswerBLL(
        ISurveyAnswerDAL answerDal,
        ISurveySummaryDAL summaryDal,
        ISurveySummaryBLL summaryBll,
        IFlsSessionBLL sessionBll,
        AutoNumber autoNumber,
        ILogger<SurveyAnswerBLL> logger)
    {
        _answerDal  = answerDal;
        _summaryDal = summaryDal;
        _summaryBll = summaryBll;
        _sessionBll = sessionBll;
        _autoNumber = autoNumber;
        _logger     = logger;
    }

    public async Task<string> SaveDraftAnswersAsync(
        SaveSurveyDraftRequest req, FlsSessionContextDto ctx,
        LoginDTO login, CancellationToken ct)
    {
        try
        {
            GB5Trace.Step("save-draft-survey-answers", new { req.FlsSessionId, count = req.Answers.Count });

            var answerIds = await AllocateAnswerIdsAsync(req.Answers.Count, login, ct).ConfigureAwait(false);
            await _answerDal.UpsertAnswersAsync(req.FlsSessionId, req.Answers, answerIds, isDraft: true, login, ct)
                .ConfigureAwait(false);

            return SuccessResponse.UpdateSuccess;
        }
        catch (Exception ex)
        {
            GB5Trace.MarkFailed("save-draft-survey-answers-failed", ex);
            _logger.LogError(ex, "SaveDraftAnswers failed for session {Id}", req.FlsSessionId);
            throw;
        }
    }

    public async Task<string> SubmitAnswersAsync(
        SubmitSurveyRequest req, FlsSessionContextDto ctx,
        LoginDTO login, CancellationToken ct)
    {
        try
        {
            GB5Trace.Step("validate-survey-answers", new { req.FlsSessionId });

            if (ctx.InstrumentConfigId == -1)
                return "No survey instrument linked to this session.";

            var answerIds = await AllocateAnswerIdsAsync(req.Answers.Count, login, ct).ConfigureAwait(false);

            GB5Trace.Step("save-survey-answers", new { req.FlsSessionId, ctx.InstrumentConfigId });
            await _answerDal.UpsertAnswersAsync(req.FlsSessionId, req.Answers, answerIds, isDraft: false, login, ct)
                .ConfigureAwait(false);

            GB5Trace.Step("submit-fls-session-from-survey", new { req.FlsSessionId });
            await _sessionBll.SubmitAsync(req.FlsSessionId, login, ct).ConfigureAwait(false);

            GB5Trace.Step("update-survey-summary-from-submit", new { ctx.InstrumentConfigId, ctx.FlsInstanceId, ctx.GroupId });
            await _summaryBll.UpdateSummaryAsync(ctx.InstrumentConfigId, ctx.FlsInstanceId, ctx.GroupId, login, ct)
                .ConfigureAwait(false);

            return SuccessResponse.UpdateSuccess;
        }
        catch (Exception ex)
        {
            GB5Trace.MarkFailed("submit-survey-answers-failed", ex);
            _logger.LogError(ex, "SubmitAnswers failed for session {Id}", req.FlsSessionId);
            throw;
        }
    }

    private async Task<List<int>> AllocateAnswerIdsAsync(int count, LoginDTO login, CancellationToken ct)
    {
        if (count == 0) return new List<int>();
        var autoNum = await _autoNumber.GetNumberAsync(count, "SURVEYANSWER", login).ConfigureAwait(false);
        return Enumerable.Range(autoNum.StartNumber, count).ToList();
    }

    public async Task<string> GetAnswersAsync(int flsSessionId, LoginDTO login, CancellationToken ct)
    {
        try
        {
            GB5Trace.Step("get-survey-answers", new { flsSessionId });
            var answers = await _answerDal.GetBySessionAsync(flsSessionId, login, ct).ConfigureAwait(false);
            return JsonSerializer.Serialize(answers);
        }
        catch (Exception ex)
        {
            GB5Trace.MarkFailed("get-survey-answers-failed", ex);
            _logger.LogError(ex, "GetAnswers failed for session {Id}", flsSessionId);
            throw;
        }
    }

}