using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using SharedKernel.Results;
using Domain.Entities.Donations.ValueObject;
using Microsoft.EntityFrameworkCore;

namespace Application.Features.Api.DonationRemote.GetCrewMembers;

internal sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Result<Response>>
{
    public async Task<Result<Response>> Handle(Query request, CancellationToken ct)
    {
        var channel = await db.Channel.AsNoTracking()
            .Where(c => c.WidgetToken == request.WidgetToken && c.IsActive)
            .Select(c => new { c.ID, c.MemberID })
            .FirstOrDefaultAsync(ct);

        if (channel is null)
        {
            return Result.Failure<Response>(Error.NotFound("Channel.NotFound", "채널을 찾을 수 없습니다."));
        }

        if (channel.MemberID != request.RequesterMemberID)
        {
            return Result.Failure<Response>(Error.Forbidden("Remote.Forbidden", "권한이 없습니다."));
        }

        var crew = await db.Crew.AsNoTracking()
            .Where(c => c.ID == request.CrewID && c.ChannelID == channel.ID && c.IsActive)
            .Select(c => new { c.ID, c.Name })
            .FirstOrDefaultAsync(ct);

        if (crew is null)
        {
            return Result.Failure<Response>(Error.NotFound("Crew.NotFound", "크루를 찾을 수 없습니다."));
        }

        var activeSessionID = await db.CrewSession.AsNoTracking()
            .Where(s => s.CrewID == crew.ID && s.Status == CrewSessionStatus.Active)
            .OrderByDescending(s => s.CreatedAt)
            .Select(s => (int?)s.ID)
            .FirstOrDefaultAsync(ct);

        // ID > 0 방어: 시드/수동 SQL로 ID=0 row가 들어간 케이스 차단
        var members = await db.CrewMember.AsNoTracking()
            .Where(m => m.CrewID == crew.ID && m.IsActive && m.ID > 0)
            .OrderBy(m => m.SortOrder).ThenBy(m => m.JoinedAt)
            .Select(m => new CrewMemberItem(
                m.ID,
                m.MemberID,
                m.Nickname,
                m.Role,
                m.SortOrder
            ))
            .ToListAsync(ct);

        return Result.Success(new Response(crew.ID, crew.Name, activeSessionID, members));
    }
}