using System;
using System.Threading;
using System.Threading.Tasks;
using FastEndpoints;
using Dapper;
using Npgsql;
using Microsoft.Extensions.Configuration;

namespace QuantEngine.Web.Endpoints;

public record UpdateThresholdRequest(string FactorId, string CalibrationState, string ThresholdParamsJson);
public record UpdateThresholdResponse(bool Success, string Message);

/// <summary>
/// BFF FastEndpoints for updating factor threshold parameter logic.
/// SOLID: Single Responsibility for updating factor settings.
/// </summary>
public class UpdateFactorThresholdEndpoint : Endpoint<UpdateThresholdRequest, UpdateThresholdResponse>
{
    private readonly string _connectionString;

    public UpdateFactorThresholdEndpoint(IConfiguration config)
    {
        _connectionString = config.GetConnectionString("DefaultConnection") 
            ?? throw new ArgumentNullException("ConnectionStrings__DefaultConnection");
    }

    public override void Configure()
    {
        Post("/api/admin/factors/update-threshold");
        AllowAnonymous();
    }

    public override async Task HandleAsync(UpdateThresholdRequest req, CancellationToken ct)
    {
        using var conn = new NpgsqlConnection(_connectionString);
        await conn.OpenAsync(ct);

        const string sql = @"
            UPDATE quantengine.factor_version_history 
            SET calibration_state = @CalibrationState, 
                threshold_params = @ThresholdParams::jsonb,
                updated_at = NOW()
            WHERE factor_id = @FactorId;";

        int affectedRows = await conn.ExecuteAsync(sql, new {
            req.FactorId,
            req.CalibrationState,
            ThresholdParams = req.ThresholdParamsJson
        });

        if (affectedRows > 0)
        {
            await SendAsync(new UpdateThresholdResponse(true, "성공적으로 반영되었습니다."), cancellation: ct);
        }
        else
        {
            await SendAsync(new UpdateThresholdResponse(false, "해당 Factor ID를 찾을 수 없습니다."), statusCode: 404, cancellation: ct);
        }
    }
}