using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Microsoft.EntityFrameworkCore;
using SharedKernel.Results;

namespace Application.Features.Api.Stocks.GetDetail;

internal sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Result<Response>>
{
    private const int RecentPriceCount = 30;

    public async Task<Result<Response>> Handle(Query request, CancellationToken ct)
    {
        var stock = await db.Stock.AsNoTracking().FirstOrDefaultAsync(c => c.Code == request.Code, ct);
        if (stock is null)
        {
            return Result.Failure<Response>(Error.NotFound("Stock.NotFound", "종목을 찾을 수 없습니다."));
        }

        var prices = await db.StockDailyPrice.AsNoTracking()
            .Where(c => c.StockID == stock.ID)
            .OrderByDescending(c => c.TradingDate)
            .Take(RecentPriceCount)
            .Select(c => new Response.PriceRow
            {
                TradingDate = c.TradingDate,
                Open = c.Open,
                High = c.High,
                Low = c.Low,
                Close = c.Close,
                Volume = c.Volume,
                TradingValue = c.TradingValue,
                ChangeAmount = c.ChangeAmount,
                ChangeRate = c.ChangeRate
            })
            .ToListAsync(ct);

        return new Response
        {
            Code = stock.Code,
            ISIN = stock.ISIN,
            Name = stock.Name,
            EnglishName = stock.EnglishName,
            Market = stock.Market.ToString(),
            TradingStatus = stock.TradingStatus.ToString(),
            SectorName = stock.SectorName,
            IsActive = stock.IsActive,
            ListedDate = stock.ListedDate,
            DelistedDate = stock.DelistedDate,
            LastTradingDate = stock.LastTradingDate,
            ClosePrice = stock.LastClosePrice,
            ChangeRate = stock.LastChangeRate,
            MarketCap = stock.MarketCap,
            RecentPrices = prices
        };
    }
}