using Application.Abstractions.Data;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SharedKernel;

namespace Infrastructure.StockData;

/// <summary>
/// 거시경제지표 수집 (KOSIS 국가통계포털 statisticsData.do) — config Indicators 를 순회하며 각 지표의
/// [today-BackfillYears, today] 시점 범위를 조회해 MacroIndicator upsert (UQ = Code+Period). 기본 07:50 KST 실행.
/// 지표별 tblId/itmId/분류코드는 config(AppSettings.Kosis.Indicators)로 주도 — 코드 변경 없이 교정 가능하다.
/// 콜 수가 적어(지표 6종 × 1회) quota 걱정은 낮지만 지표 사이 DelayMs 간격을 둔다. 빈 응답·err JSON·미고시 시점은
/// 정상(0건)으로 취급해 그 지표만 skip 하고 다음으로 넘어간다. 예외 발생 시 경고 후 false 반환(다음 날/재시도).
/// </summary>
internal sealed class KosisSyncService(
    IServiceScopeFactory scopeFactory,
    IHttpClientFactory httpClientFactory,
    IOptions<AppSettings> settings,
    ILogger<KosisSyncService> logger
) : DailyScheduledService(logger)
{
    protected override string JobName => "KosisSync";

    protected override TimeOnly TargetTime => ParseTime(settings.Value.Kosis.SyncTime, new TimeOnly(7, 50));

    protected override int MaxRetryCount => 2;

    protected override TimeSpan RetryDelay => TimeSpan.FromHours(1);

    protected override async Task<bool> RunOnceAsync(DateOnly todayKst, CancellationToken ct)
    {
        var cfg = settings.Value.Kosis;

        if (string.IsNullOrWhiteSpace(cfg.ApiKey))
        {
            Logger.LogWarning("[{Job}] Kosis:ApiKey 미설정 — 수집 skip", JobName);
            return true;
        }

        if (cfg.Indicators.Count == 0)
        {
            Logger.LogWarning("[{Job}] Kosis:Indicators 비어 있음 — 수집 skip", JobName);
            return true;
        }

        using var scope = scopeFactory.CreateScope();
        var db = scope.ServiceProvider.GetRequiredService<IAppDbContext>();
        var client = httpClientFactory.CreateClient(KosisHttp.ClientName);

        var baseUrl = cfg.BaseUrl.TrimEnd('/');
        var years = cfg.BackfillYears > 0 ? cfg.BackfillYears : 5;
        var startYear = todayKst.AddYears(-years);
        var ok = true;

        foreach (var indicator in cfg.Indicators)
        {
            ct.ThrowIfCancellationRequested();

            if (string.IsNullOrWhiteSpace(indicator.Code) || string.IsNullOrWhiteSpace(indicator.OrgId) || string.IsNullOrWhiteSpace(indicator.TblId))
            {
                Logger.LogWarning("[{Job}] 지표 정의 불완전 (Code/OrgId/TblId) — skip: Code={Code}", JobName, indicator.Code);
                continue;
            }

            try
            {
                var (inserted, updated) = await FetchAndUpsertAsync(db, client, baseUrl, cfg.ApiKey, indicator, startYear, todayKst, ct);
                Logger.LogInformation("[{Job}] {Code}({Tbl}) 완료 — inserted={Ins}, updated={Upd}", JobName, indicator.Code, indicator.TblId, inserted, updated);
            }
            catch (OperationCanceledException)
            {
                throw;
            }
            catch (Exception ex)
            {
                ok = false;
                Logger.LogWarning(ex, "[{Job}] {Code}({Tbl}) 수집 실패 — 다음 지표 계속", JobName, indicator.Code, indicator.TblId);
            }

            if (cfg.DelayMs > 0)
            {
                await Task.Delay(cfg.DelayMs, ct);
            }
        }

        return ok;
    }

    private async Task<(int Inserted, int Updated)> FetchAndUpsertAsync(
        IAppDbContext db,
        HttpClient client,
        string baseUrl,
        string apiKey,
        AppSettings.KosisSection.KosisIndicator indicator,
        DateOnly startDate,
        DateOnly today,
        CancellationToken ct
    ) {
        var cycle = string.IsNullOrWhiteSpace(indicator.Cycle) ? "M" : indicator.Cycle.Trim().ToUpperInvariant();
        var startPrd = FormatPeriod(startDate, cycle);
        var endPrd = FormatPeriod(today, cycle);
        var itmId = string.IsNullOrWhiteSpace(indicator.ItmId) ? "ALL" : indicator.ItmId.Trim();
        var objL1 = string.IsNullOrWhiteSpace(indicator.ObjL1) ? "ALL" : indicator.ObjL1.Trim();

        var url = $"{baseUrl}?method=getList&apiKey={apiKey}&format=json&jsonVD=Y&orgId={indicator.OrgId}&tblId={indicator.TblId}&itmId={itmId}&objL1={objL1}&prdSe={cycle}&startPrdDe={startPrd}&endPrdDe={endPrd}";
        var json = await KosisHttp.GetStringWithRetryAsync(client, url, Logger, ct);
        var parsed = KosisParser.Parse(json);

        Logger.LogInformation("[{Job}] {Code} prdSe={Cycle} [{Start}~{End}] rows={Rows}", JobName, indicator.Code, cycle, startPrd, endPrd, parsed.Count);

        if (parsed.Count == 0)
        {
            return (0, 0);
        }

        return await KosisImport.UpsertAsync(db, indicator, parsed, ct);
    }

    /// <summary>KOSIS prdSe 별 시점 형식 — M=YYYYMM, Q=YYYYQ(분기 1~4), Y=YYYY.</summary>
    private static string FormatPeriod(DateOnly date, string cycle)
    {
        return cycle switch
        {
            "Y" => date.Year.ToString("D4"),
            "Q" => $"{date.Year:D4}{(date.Month - 1) / 3 + 1}",
            _ => $"{date.Year:D4}{date.Month:D2}"
        };
    }
}