ANTOOZA-BACKEND/Application/Features/Api/Stocks/GetWorldIndices/Handler.cs

using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Domain.Entities.Stocks.ValueObject;
using Microsoft.EntityFrameworkCore;

namespace Application.Features.Api.Stocks.GetWorldIndices;

/// <summary>
/// 세계 주요국 증시지수 병합 — 국내(코스피)는 IndexDailyPrice 최신 거래일 실데이터, 해외는 WorldIndexSnapshot(나라당 1개).
/// 국가 코드(ISO2)로 프론트가 세계지도 핀 좌표를 매핑한다. 해외 스냅샷에 KR 이 섞여도 중복 방지로 제외.
/// </summary>
internal sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Response>
{
    public async Task<Response> Handle(Query request, CancellationToken ct)
    {
        var rows = new List<Response.Row>();

        // 국내(코스피) — IndexDailyPrice 최신 거래일. 한국 핀은 KRX 실데이터 사용.
        var latestKr = await db.IndexDailyPrice.AsNoTracking().OrderByDescending(c => c.TradeDate).Select(c => (DateOnly?)c.TradeDate).FirstOrDefaultAsync(ct);

        if (latestKr is not null)
        {
            var kospi = await db.IndexDailyPrice.AsNoTracking()
                .Where(c => c.TradeDate == latestKr.Value && c.Series == MarketIndexSeries.KOSPI && c.IndexName == "코스피")
                .Select(c => new
                {
                    c.Close,
                    c.ChangeVal,
                    c.FlucRateBp,
                    c.TradeDate
                })
                .FirstOrDefaultAsync(ct);

            if (kospi is not null)
            {
                rows.Add(new Response.Row
                {
                    CountryCode = "KR",
                    Name = "코스피",
                    ExchangeName = "KRX",
                    Close = kospi.Close,
                    ChangeVal = kospi.ChangeVal,
                    FlucRateBp = kospi.FlucRateBp,
                    TradeDate = kospi.TradeDate
                });
            }
        }

        // 해외 — WorldIndexSnapshot (config Items 로 나라당 1개). KR 은 위에서 병합했으므로 제외.
        var foreign = await db.WorldIndexSnapshot.AsNoTracking()
            .Where(c => c.CountryCode != "KR")
            .OrderBy(c => c.CountryCode)
            .Select(c => new Response.Row
            {
                CountryCode = c.CountryCode,
                Name = c.Name,
                ExchangeName = c.ExchangeName,
                Close = c.Close,
                ChangeVal = c.ChangeVal,
                FlucRateBp = c.FlucRateBp,
                TradeDate = c.TradeDate
            })
            .ToListAsync(ct);

        rows.AddRange(foreign);

        return new Response
        {
            List = rows
        };
    }
}