package io.hhplus.concert.application.usecase.payment;

@Service
@RequiredArgsConstructor
public class PaymentUsecase {
 @Transactional
 public PaymentResult.PayAndConfirm payAndConfirm(PaymentCriteria.PayAndConfirm criteria) {
    // 유저포인트 조회
    UserInfo.GetUserPoint userPointInfo = userService.getUserPoint(UserPointCommand.GetUserPoint.of(criteria.userId()));
    UserPoint userPoint = userPointInfo.userPoint();

    // 예약데이터 조회
    ReservationInfo.Get reservationInfo = reservationService.get(ReservationCommand.Get.of(criteria.reservationId()));

    Reservation reservation = reservationInfo.reservation();
    long concertSeatPrice = reservation.getConcertSeat().getPrice();
    long concertId = reservation.getConcert().getId();
    long concertDateId = reservation.getConcertDate().getId();

    // 임시예약상태일 경우에 결제 가능
    if(reservation.isTemporary()) {
        // 포인트 사용
        userService.usePoint(UserPointCommand.UsePoint.of(criteria.userId(), concertSeatPrice));

        // 예약 확정 변경
        reservation.confirm();

        // 결제처리 및 결제정보 반환
        PaymentInfo.CreatePayment paymentInfo = paymentService.create(
            PaymentCommand.CreatePayment.of(reservation)
        );

        // 매진 확인 및 매진처리
        // 전체 좌석의 개수를 구한다
        long totalSeats = concertService.countTotalSeats(ConcertCommand.CountTotalSeats.of(concertId, concertDateId));

        // 확정상태의 예약 개수를 구한다
        long confirmedSeatsCount = reservationService.countConfirmedSeats(ReservationCommand.CountConfirmedSeats.of(concertId, concertDateId));

        // 전좌석이 모두 예약확정 상태라면
        if( totalSeats == confirmedSeatsCount) {

            // 전좌석 예약확정이므로 해당콘서트일정은 매진상태이므로 예약불가능한 상태로 변경한다.
            ConcertDate soldOutConcertDate = concertService.soldOut(concertDateId);

            // 매진됐다면, 매진시점에 일간 인기콘서트 에 넣는다.
            concertRankingRepository.recordDailyFamousConcertRanking(String.valueOf(concertId), soldOutConcertDate.getProgressDate().toString());
        }
        return PaymentResult.PayAndConfirm.of(paymentInfo);
    }

    throw new BusinessException(NOT_VALID_STATUS_FOR_PAYMENT);
 }
}

package io.hhplus.concert.application.usecase.payment;

@Service
@RequiredArgsConstructor
public class PaymentUsecase {

 @Transactional
 public PaymentResult.PayAndConfirm payAndConfirm(PaymentCriteria.PayAndConfirm criteria) {

    // 유저포인트 조회
    UserInfo.GetUserPoint userPointInfo = userService.getUserPoint(UserPointCommand.GetUserPoint.of(criteria.userId()));
    UserPoint userPoint = userPointInfo.userPoint();

    // 예약데이터 조회
    ReservationInfo.Get reservationInfo = reservationService.get(ReservationCommand.Get.of(criteria.reservationId()));

    Reservation reservation = reservationInfo.reservation();
    long concertSeatPrice = reservation.getConcertSeat().getPrice();
    long concertId = reservation.getConcert().getId();
    long concertDateId = reservation.getConcertDate().getId();

    // 임시예약상태일 경우에 결제 가능
    if(reservation.isTemporary()) {
        // 포인트 사용
        userService.usePoint(
            UserPointCommand.UsePoint.of(criteria.userId(), concertSeatPrice)
        );

        // 예약 확정 변경
        reservation.confirm();

        // 결제처리 및 결제정보 반환
        PaymentInfo.CreatePayment paymentInfo = paymentService.create(PaymentCommand.CreatePayment.of(reservation));

        // ✨ 결제성공 이벤트 발행
        paymentSuccessEventPublisher.publishEvent(reservation.getId(),  concertId,concertDateId);

        return PaymentResult.PayAndConfirm.of(paymentInfo);
    }

    throw new BusinessException(NOT_VALID_STATUS_FOR_PAYMENT);
 }
}

package io.hhplus.concert.domain.payment;

public record PaymentSuccessEvent(
    Long reservationId,
    Long concertId,
    Long concertDateId
) { }

package io.hhplus.concert.domain.payment;

public interface PaymentSuccessEventPublisher {
 void publishEvent(long reservationId, long concertId, long concertDateId);
}

package io.hhplus.concert.infrastructure.events;

@Component
@RequiredArgsConstructor
public class PaymentSuccessEventPublisherImpl implements PaymentSuccessEventPublisher {
 private final ApplicationEventPublisher eventPublisher;

 @Override
 public void publishEvent(long reservationId, long concertId, long concertDateId) {
  // Spring이 제공하는 내장 이벤트 퍼블리셔를 사용하여 이벤트 발행
  eventPublisher.publishEvent(new PaymentSuccessEvent(reservationId, concertId, concertDateId));
 }
}

package io.hhplus.concert.interfaces.events;

@Component
@RequiredArgsConstructor
public class PaymentSuccessEventListener {

 // 결제 성공후 매진확인 및 콘서트날짜 매진 처리 로직
 @Async
 @TransactionalEventListener(phase = TransactionPhase.AFTER_COMMIT)
 public void handleSoldOutConcertDate(PaymentSuccessEvent event) {
    long reservationId = event.reservationId();
    long concertId = event.concertId();
    long concertDateId = event.concertDateId();

    log.info("[PaymentSuccessEventListener] 예약 ID: {} 결제완료", reservationId);
    try {
        // 전체 좌석의 개수를 구한다
        long totalSeats = concertService.countTotalSeats(
                ConcertCommand.CountTotalSeats.of(concertId, concertDateId)
            );

        // 확정상태의 예약 개수를 구한다
        long confirmedSeatsCount = reservationService.countConfirmedSeats(
            ReservationCommand.CountConfirmedSeats.of(concertId, concertDateId));

        // 전좌석이 모두 예약확정 상태라면
        if( totalSeats == confirmedSeatsCount) {
            // 전좌석 예약확정이므로 해당콘서트일정은 매진상태이므로 예약불가능한 상태로 변경한다.
            ConcertDate soldOutConcertDate = concertService.soldOut(concertDateId);

            // 매진됐다면, 매진시점에 일간 인기콘서트에 추가한다
            concertRankingRepository.recordDailyFamousConcertRanking(
                String.valueOf(concertId),
                soldOutConcertDate.getProgressDate().toString()
            );
        }

    } catch(BusinessException e) {
        log.error("[매진 처리 실패] concertId={}, concertDateId={}, reason: {}", concertId, concertDateId, e.getMessage(), e);

        // ✏️ 예상가능한 예외가 발생시 해당예외 리포트
        soldOutConcertDateFailEventPublisher.publishEvent(concertId, concertDateId, e.getMessage(), e);

    } catch(Exception e) {
        log.error("[예상치 못한 매진 처리 실패] concertId={}, concertDateId={}", concertId, concertDateId, e);

        // ✏️ 정의되지않은 예외가 발생시 해당예외 리포트
        soldOutConcertDateFailEventPublisher.publishEvent(concertId, concertDateId, "Unexpected", e);
    }
 }
}

package io.hhplus.concert.domain.payment;

public record SoldOutConcertDateFailEvent(
    long concertId,
    long concertDateId,
    String reason,
    Throwable cause
) { }

package io.hhplus.concert.domain.payment;

public interface SoldOutConcertDateFailEventPublisher {
 void publishEvent(long concertId, long concertDateId, String reason, Throwable cause);
}

package io.hhplus.concert.infrastructure.events;

@Component
@RequiredArgsConstructor
public class SoldOutConcertDateFailEventPublisherImpl implements SoldOutConcertDateFailEventPublisher {
 private final ApplicationEventPublisher eventPublisher;

 @Override
 public void publishEvent(long concertId, long concertDateId, String reason, Throwable cause) {
  // Spring이 제공하는 내장 이벤트 퍼블리셔를 사용하여 이벤트를 발행한다
  eventPublisher.publishEvent(new SoldOutConcertDateFailEvent(concertId, concertDateId, reason, cause));
 }
}

package io.hhplus.concert.interfaces.events;

@Component
@RequiredArgsConstructor
public class SoldOutConcertDateFailEventListener {
 private static final Logger log = LoggerFactory.getLogger(SoldOutConcertDateFailEventListener.class);

 @Async
 @EventListener
 public void handleReportSlackOfSoldOutConcertDateFailEvent(SoldOutConcertDateFailEvent event) {
  log.error("[슬랙 리포팅 대상] 매진처리 실패: concertId={}, concertDateId={}, reason={}",
    event.concertId(),
    event.concertDateId(),
    event.reason(),
    event.cause()
  );
 }
}