using Application.Abstractions.Data;
using Application.Helpers;
using Domain.Entities.Stocks;
using Domain.Entities.Stocks.ValueObject;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SharedKernel;

namespace Infrastructure.StockData;

/// <summary>
/// 종목 마스터 동기화 — 금융위 KRX 상장종목정보 API 를 일 1회(기본 07:30 KST) 전량 수집하여 Stock upsert.
/// 신규 상장 = insert, 명칭/시장 변경 = update, 스냅샷에서 사라진 종목 = 상폐 soft-off.
/// 단일 엔드포인트 페이징 수집이라 조기 종료/페이지 상한 시 부분 스냅샷이 될 수 있으므로,
/// 상폐 sweep 은 시장별 가드(StockMasterDelist — 0건 또는 활성 대비 80% 미만이면 보류+경고)를 통과한 시장에서만 수행.
/// ServiceKey 미설정 시 로그만 남기고 skip.
/// </summary>
internal sealed class StockMasterSyncService(
    IServiceScopeFactory scopeFactory,
    IHttpClientFactory httpClientFactory,
    IOptions<AppSettings> settings,
    ILogger<StockMasterSyncService> logger
) : DailyScheduledService(logger)
{
    private const string ServicePath = "/1160100/service/GetKrxListedInfoService/getItemInfo";
    private const int MaxPages = 50;
    private const int MaxBaseDateLookback = 7;

    protected override string JobName => "StockMasterSync";

    protected override TimeOnly TargetTime => ParseTime(settings.Value.StockData.MasterSyncTime, new TimeOnly(7, 30));

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

        using var scope = scopeFactory.CreateScope();
        var collectorSettings = scope.ServiceProvider.GetRequiredService<ICollectorSettingsProvider>();
        if (!await collectorSettings.IsEnabledAsync(CollectorFlag.StockDataMaster, ct))
        {
            return true;
        }
        cfg = cfg with { ServiceKey = await collectorSettings.GetKeyAsync(CollectorKey.DataGoKr, ct) ?? cfg.ServiceKey };
        if (string.IsNullOrWhiteSpace(cfg.ServiceKey))
        {
            Logger.LogWarning("[{Job}] StockData:DataGoKr:ServiceKey 미설정 — 수집 skip", JobName);
            return true;
        }
        var db = scope.ServiceProvider.GetRequiredService<IAppDbContext>();
        var client = httpClientFactory.CreateClient(DataGoKrHttp.ClientName);

        // 상장종목정보는 basDt 단위 스냅샷 — 직전 영업일부터 최대 7일 소급하며 데이터가 있는 기준일을 찾는다
        var baseDate = await MarketCalendar.GetPreviousBusinessDayAsync(db, todayKst.AddDays(1), ct);
        List<DataGoKrStockParser.ListedItem>? snapshot = null;

        for (var back = 0; back < MaxBaseDateLookback; back++)
        {
            snapshot = await FetchSnapshotAsync(client, cfg, baseDate, ct);
            if (snapshot.Count > 0)
            {
                break;
            }

            baseDate = await MarketCalendar.GetPreviousBusinessDayAsync(db, baseDate, ct);
        }

        if (snapshot is null || snapshot.Count == 0)
        {
            Logger.LogError("[{Job}] 상장종목 스냅샷 없음 — 최근 {Days}영업일 조회 실패", JobName, MaxBaseDateLookback);
            return true;
        }

        // 동일 코드 중복 행은 마지막 행 우선. 상폐 sweep 가드용으로 시장별 건수도 함께 집계 (0건 시장 포함)
        var byCode = new Dictionary<string, DataGoKrStockParser.ListedItem>();
        var snapshotCountByMarket = new Dictionary<StockMarket, int> { [StockMarket.KOSPI] = 0, [StockMarket.KOSDAQ] = 0, [StockMarket.KONEX] = 0 };
        foreach (var item in snapshot)
        {
            var market = MapMarket(item.MarketName);
            if (market is null)
            {
                continue;
            }

            if (!byCode.ContainsKey(item.Code))
            {
                snapshotCountByMarket[market.Value]++;
            }

            byCode[item.Code] = item;
        }

        var stocks = await db.Stock.ToListAsync(ct);
        var stockByCode = stocks.ToDictionary(c => c.Code);
        var inserted = 0;
        var updated = 0;
        var delisted = 0;

        foreach (var (code, item) in byCode)
        {
            var market = MapMarket(item.MarketName)!.Value;

            if (stockByCode.TryGetValue(code, out var stock))
            {
                var wasUpdated = stock.UpdatedAt;
                stock.UpdateMaster(item.Name, market, item.Isin);
                if (stock.UpdatedAt != wasUpdated)
                {
                    updated++;
                }
            }
            else
            {
                await db.Stock.AddAsync(Stock.Create(code, item.Name, market, item.BaseDate, item.Isin), ct);
                inserted++;
            }
        }

        // 스냅샷에서 사라진 활성 종목 = 상폐 soft-off — 단, 시장별 가드(빈 응답/활성 대비 80% 미만)를 통과한 시장만
        var activeCountByMarket = stocks.Where(c => c.IsActive).GroupBy(c => c.Market).ToDictionary(c => c.Key, c => c.Count());
        var delistableMarkets = StockMasterDelist.GetDelistableMarkets(snapshotCountByMarket, activeCountByMarket).ToHashSet();

        foreach (var (market, snapshotCount) in snapshotCountByMarket.Where(c => !delistableMarkets.Contains(c.Key)))
        {
            Logger.LogWarning("[{Job}] {Market} 상폐 sweep 보류 — snapshot={Snapshot}, active={Active} (빈/부분 응답 방어)",
                JobName, market, snapshotCount, activeCountByMarket.TryGetValue(market, out var active) ? active : 0);
        }

        foreach (var stock in stocks.Where(c => c.IsActive && delistableMarkets.Contains(c.Market) && !byCode.ContainsKey(c.Code)))
        {
            stock.MarkDelisted(baseDate);
            delisted++;
        }

        await db.SaveChangesAsync(ct);

        Logger.LogInformation("[{Job}] 완료 — basDt={BaseDate}, snapshot={Snapshot}, inserted={Inserted}, updated={Updated}, delisted={Delisted}",
            JobName, baseDate, byCode.Count, inserted, updated, delisted);

        return true;
    }

    private async Task<List<DataGoKrStockParser.ListedItem>> FetchSnapshotAsync(HttpClient client, AppSettings.StockDataSection.DataGoKrSection cfg, DateOnly baseDate, CancellationToken ct)
    {
        var all = new List<DataGoKrStockParser.ListedItem>();
        var totalCount = int.MaxValue;

        for (var pageNo = 1; pageNo <= MaxPages && all.Count < totalCount; pageNo++)
        {
            var url = $"{cfg.BaseUrl.TrimEnd('/')}{ServicePath}?serviceKey={Uri.EscapeDataString(cfg.ServiceKey)}&resultType=json&numOfRows={cfg.PageSize}&pageNo={pageNo}&basDt={baseDate:yyyyMMdd}";
            var json = await DataGoKrHttp.GetStringWithRetryAsync(client, url, Logger, ct);
            var (items, total) = DataGoKrStockParser.ParseListedItems(json);

            totalCount = total;
            if (items.Count == 0)
            {
                break;
            }

            all.AddRange(items);
        }

        return all;
    }

    private static StockMarket? MapMarket(string marketName)
    {
        if (marketName.Contains("KOSPI", StringComparison.OrdinalIgnoreCase))
        {
            return StockMarket.KOSPI;
        }

        if (marketName.Contains("KOSDAQ", StringComparison.OrdinalIgnoreCase))
        {
            return StockMarket.KOSDAQ;
        }

        if (marketName.Contains("KONEX", StringComparison.OrdinalIgnoreCase))
        {
            return StockMarket.KONEX;
        }

        return null;
    }
}