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

namespace Application.Features.Api.Stocks.GetElsRiskBoard;

internal sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Result<Response>>
{
    public async Task<Result<Response>> Handle(Query request, CancellationToken ct)
    {
        var query = db.ElsUnredeemedScale.AsNoTracking();

        var bassetCd = request.BassetCd?.Trim();
        if (!string.IsNullOrEmpty(bassetCd))
        {
            query = query.Where(c => c.StndBassetCd == bassetCd);
        }

        var secnTpcd = request.SecnTpcd?.Trim();
        if (!string.IsNullOrEmpty(secnTpcd))
        {
            query = query.Where(c => c.SecnTpcd == secnTpcd);
        }

        if (request.From.HasValue)
        {
            query = query.Where(c => c.StdDt >= request.From.Value);
        }

        if (request.To.HasValue)
        {
            query = query.Where(c => c.StdDt <= request.To.Value);
        }

        // 기초자산코드 × 종목구분별로 그룹화하고, 각 그룹 안에서 기준일 오름차순 시계열을 만든다.
        var rows = await query
            .OrderBy(c => c.StndBassetCd).ThenBy(c => c.SecnTpcd).ThenBy(c => c.StdDt)
            .Select(c => new
            {
                c.StndBassetCd,
                c.SecnTpcd,
                c.BassetContent,
                c.StdDt,
                c.UnredSecncnt,
                c.UnredRema
            })
            .ToListAsync(ct);

        var series = rows
            .GroupBy(c => new { c.StndBassetCd, c.SecnTpcd })
            .Select(g => new Response.Series
            {
                BassetCd = g.Key.StndBassetCd,
                SecnTpcd = g.Key.SecnTpcd,
                BassetContent = g.Select(c => c.BassetContent).FirstOrDefault(c => c != null),
                Points = g.Select(c => new Response.Point
                {
                    StdDt = c.StdDt,
                    UnredeemedCount = c.UnredSecncnt,
                    UnredeemedRemaining = c.UnredRema
                }).ToList()
            })
            .ToList();

        return new Response { Assets = series };
    }
}