ANTOOZA-BACKEND/Application/Features/Api/Note/DeleteNote/Handler.cs

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

namespace Application.Features.Api.Note.DeleteNote;

internal sealed class Handler(IAppDbContext db) : ICommandHandler<Command, Result>
{
    public async Task<Result> Handle(Command r, CancellationToken ct)
    {
        // 받은쪽지 또는 보낸쪽지 둘 다 처리 — 본인이 receiver 면 DeleteByReceiver, sender 면 DeleteBySender
        var note = await db.Note
            .Where(n => n.ID == r.NoteID && (
                (n.ReceiverMemberID == r.CurrentMemberID && !n.IsDeletedByReceiver) ||
                (n.SenderMemberID == r.CurrentMemberID && !n.IsDeletedBySender)
            ))
            .FirstOrDefaultAsync(ct);

        if (note is null)
        {
            return Result.Failure(Error.NotFound("Note.NotFound", "쪽지를 찾을 수 없습니다."));
        }

        if (note.ReceiverMemberID == r.CurrentMemberID && !note.IsDeletedByReceiver)
        {
            note.DeleteByReceiver();
        }
        else if (note.SenderMemberID == r.CurrentMemberID && !note.IsDeletedBySender)
        {
            note.DeleteBySender();
        }

        await db.SaveChangesAsync(ct);

        return Result.Success();
    }
}