[FEATURE] 결제 취소 기능 및 결제 내역 조회 기능 구현

src/main/java/com/sudo/railo/booking/application/ReservationApplicationService.java

@@ -67,7 +67,6 @@ public ReservationCreateResponse createReservation(ReservationCreateRequest requ
 
 	@Transactional
 	public void cancelReservation(Reservation reservation) {
-		reservation.cancel();
 		Long reservationId = reservation.getId();
 		seatReservationService.deleteSeatReservationByReservationId(reservationId);
 		ticketService.deleteTicketByReservationId(reservationId);

src/main/java/com/sudo/railo/payment/application/PaymentService.java

@@ -1,21 +1,27 @@
 package com.sudo.railo.payment.application;
 
 import java.math.BigDecimal;
+import java.util.List;
 
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import com.sudo.railo.booking.application.ReservationApplicationService;
 import com.sudo.railo.booking.application.TicketService;
 import com.sudo.railo.booking.domain.Reservation;
+import com.sudo.railo.booking.exception.BookingError;
 import com.sudo.railo.booking.infrastructure.reservation.ReservationRepository;
 import com.sudo.railo.global.exception.error.BusinessException;
 import com.sudo.railo.member.domain.Member;
 import com.sudo.railo.member.exception.MemberError;
 import com.sudo.railo.member.infrastructure.MemberRepository;
 import com.sudo.railo.payment.application.dto.PaymentInfo;
+import com.sudo.railo.payment.application.dto.projection.PaymentProjection;
 import com.sudo.railo.payment.application.dto.request.PaymentProcessAccountRequest;
 import com.sudo.railo.payment.application.dto.request.PaymentProcessCardRequest;
 import com.sudo.railo.payment.application.dto.request.PaymentProcessRequest;
+import com.sudo.railo.payment.application.dto.response.PaymentCancelResponse;
+import com.sudo.railo.payment.application.dto.response.PaymentHistoryResponse;
 import com.sudo.railo.payment.application.dto.response.PaymentProcessResponse;
 import com.sudo.railo.payment.domain.Payment;
 import com.sudo.railo.payment.domain.status.PaymentStatus;
@@ -37,6 +43,7 @@ public class PaymentService {
 	private final MemberRepository memberRepository;
 	private final PaymentRepository paymentRepository;
 	private final PaymentKeyGenerator paymentKeyGenerator;
+	private final ReservationApplicationService reservationApplicationService;
 	private final TicketService ticketService;
 
 	/**
@@ -146,7 +153,6 @@ private void executePaymentApproval(Payment payment, Reservation reservation) {
 
 	private void markReservationAsPaid(Reservation reservation) {
 		reservation.approve();
-		reservationRepository.save(reservation);
 
 		log.info("예약 결제 완료 처리: reservationId={}", reservation.getId());
 	}
@@ -164,4 +170,102 @@ private void generateTicket(Reservation reservation) {
 			.forEach(seatInfoProjection -> ticketService.createTicket(
 				reservation, seatInfoProjection.getSeat(), seatInfoProjection.getPassengerType()));
 	}
+
+	@Transactional
+	public PaymentCancelResponse cancelPayment(String memberNo, String paymentKey) {
+		Payment payment = findPayment(memberNo, paymentKey);
+
+		// 결제 취소 처리
+		payment.cancel("사용자 요청에 의한 취소");
+
+		markReservationAsCancelled(payment.getReservation());
+
+		log.info("결제 취소 완료: paymentKey={}, reservationId={}", paymentKey, payment.getReservation().getId());
+
+		// 즉각 환불 처리 (임시)
+		refundPayment(payment, payment.getReservation());
+
+		return PaymentCancelResponse.from(payment);
+	}
+
+	private Payment findPayment(String memberNo, String paymentKey) {
+		Member member = memberRepository.findByMemberNo(memberNo)
+			.orElseThrow(() -> new BusinessException(MemberError.USER_NOT_FOUND));
+
+		Payment payment = paymentRepository.findByPaymentKey(paymentKey)
+			.orElseThrow(() -> new BusinessException(PaymentError.PAYMENT_NOT_FOUND));
+
+		validatePaymentCancellableCondition(member, payment);
+
+		return payment;
+	}
+
+	private void validatePaymentCancellableCondition(Member member, Payment payment) {
+		// 결제 소유자 확인
+		if (!payment.getMember().getId().equals(member.getId())) {
+			throw new BusinessException(PaymentError.PAYMENT_ACCESS_DENIED);
+		}
+
+		// 결제 취소 가능 여부 확인
+		if (!payment.canBeCancelled()) {
+			throw new BusinessException(PaymentError.PAYMENT_NOT_CANCELLABLE);
+		}
+
+		// 예약 취소 가능 여부 확인
+		if (!payment.getReservation().canBeCancelled()) {
+			throw new BusinessException(BookingError.RESERVATION_DELETE_FAILED);
+		}
+	}
+
+	private void markReservationAsCancelled(Reservation reservation) {
+		reservation.cancel();
+		reservationApplicationService.cancelReservation(reservation);
+
+		log.info("예약 취소 처리: reservationId={}", reservation.getId());
+	}
+
+	/**
+	 * 환불 처리
+	 * @param payment {@link Payment} 객체
+	 */
+	public void refundPayment(Payment payment, Reservation reservation) {
+		// 해당 로직은 외부 엔드포인트가 존재하지 않고 추후 엔드포인트가 생긴다고 하더라도
+		// 신뢰할 수 있는 PG사에서 환불 완료된 결제에 대해서만 호출할 예정이기 때문에 검증 과정이 필요 없습니다.
+
+		// 즉각 환불 처리 로직 (임시)
+		if (payment.canBeRefunded()) {
+			payment.refund();
+		}
+
+		markReservationAsRefunded(reservation);
+
+		log.info("환불 처리 완료: paymentKey={}", payment.getPaymentKey());
+	}
+
+	private void markReservationAsRefunded(Reservation reservation) {
+		reservation.refund();
+
+		log.info("예약 환불 처리: reservationId={}", reservation.getId());
+	}
+
+	/**
+	 * 결제 내역 조회
+	 * @param memberNo 회원번호
+	 * @return {@code List<PaymentHistoryResponse>}
+	 */
+	@Transactional(readOnly = true)
+	public List<PaymentHistoryResponse> getPaymentHistory(String memberNo) {
+		Member member = memberRepository.findByMemberNo(memberNo)
+			.orElseThrow(() -> new BusinessException(MemberError.USER_NOT_FOUND));
+
+		List<PaymentProjection> paymentProjections = paymentRepository.findPaymentHistoryByMemberId(member.getId());
+
+		return paymentProjections.stream()
+			.map(paymentProjection -> new PaymentHistoryResponse(
+				paymentProjection.getPaymentId(), paymentProjection.getPaymentKey(),
+				paymentProjection.getReservationCode(), paymentProjection.getAmount(),
+				paymentProjection.getPaymentMethod(), paymentProjection.getPaymentStatus(),
+				paymentProjection.getPaidAt(), paymentProjection.getCancelledAt(), paymentProjection.getRefundedAt()))
+			.toList();
+	}
 }

src/main/java/com/sudo/railo/payment/application/dto/projection/PaymentProjection.java

@@ -0,0 +1,39 @@
+package com.sudo.railo.payment.application.dto.projection;
+
+import java.math.BigDecimal;
+import java.time.LocalDateTime;
+
+import com.querydsl.core.annotations.QueryProjection;
+import com.sudo.railo.payment.domain.status.PaymentStatus;
+import com.sudo.railo.payment.domain.type.PaymentMethod;
+
+import lombok.Getter;
+
+@Getter
+public class PaymentProjection {
+
+	private final Long paymentId;
+	private final String paymentKey;
+	private final String reservationCode;
+	private final BigDecimal amount;
+	private final PaymentMethod paymentMethod;
+	private final PaymentStatus paymentStatus;
+	private final LocalDateTime paidAt;
+	private final LocalDateTime cancelledAt;
+	private final LocalDateTime refundedAt;
+
+	@QueryProjection
+	public PaymentProjection(Long paymentId, String paymentKey, String reservationCode,
+		BigDecimal amount, PaymentMethod paymentMethod, PaymentStatus paymentStatus,
+		LocalDateTime paidAt, LocalDateTime cancelledAt, LocalDateTime refundedAt) {
+		this.paymentId = paymentId;
+		this.paymentKey = paymentKey;
+		this.reservationCode = reservationCode;
+		this.amount = amount;
+		this.paymentMethod = paymentMethod;
+		this.paymentStatus = paymentStatus;
+		this.paidAt = paidAt;
+		this.cancelledAt = cancelledAt;
+		this.refundedAt = refundedAt;
+	}
+}

src/main/java/com/sudo/railo/payment/infrastructure/PaymentRepository.java

@@ -10,7 +10,7 @@
 import com.sudo.railo.payment.domain.status.PaymentStatus;
 
 @Repository
-public interface PaymentRepository extends JpaRepository<Payment, Long> {
+public interface PaymentRepository extends JpaRepository<Payment, Long>, PaymentRepositoryCustom {
 
 	/**
 	 * 결제 키로 결제 정보 조회

src/main/java/com/sudo/railo/payment/infrastructure/PaymentRepositoryCustom.java

@@ -0,0 +1,16 @@
+package com.sudo.railo.payment.infrastructure;
+
+import java.util.List;
+
+import com.sudo.railo.payment.application.dto.projection.PaymentProjection;
+
+public interface PaymentRepositoryCustom {
+
+	/**
+	 * 회원의 결제 히스토리를 프로젝션으로 조회 (가장 효율적)
+	 *
+	 * @param memberId 회원 ID
+	 * @return PaymentHistoryResponse 리스트 (필요한 필드만 조회)
+	 */
+	List<PaymentProjection> findPaymentHistoryByMemberId(Long memberId);
+}

src/main/java/com/sudo/railo/payment/infrastructure/PaymentRepositoryCustomImpl.java

@@ -0,0 +1,42 @@
+package com.sudo.railo.payment.infrastructure;
+
+import static com.sudo.railo.booking.domain.QReservation.*;
+import static com.sudo.railo.member.domain.QMember.*;
+import static com.sudo.railo.payment.domain.QPayment.*;
+
+import java.util.List;
+
+import org.springframework.stereotype.Repository;
+
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import com.sudo.railo.payment.application.dto.projection.PaymentProjection;
+import com.sudo.railo.payment.application.dto.projection.QPaymentProjection;
+
+import lombok.RequiredArgsConstructor;
+
+@Repository
+@RequiredArgsConstructor
+public class PaymentRepositoryCustomImpl implements PaymentRepositoryCustom {
+
+	private final JPAQueryFactory queryFactory;
+
+	@Override
+	public List<PaymentProjection> findPaymentHistoryByMemberId(Long memberId) {
+		return queryFactory
+			.select(new QPaymentProjection(
+				payment.id,
+				payment.paymentKey,
+				reservation.reservationCode,
+				payment.amount,
+				payment.paymentMethod,
+				payment.paymentStatus,
+				payment.paidAt,
+				payment.cancelledAt,
+				payment.refundedAt))
+			.from(payment)
+			.join(payment.member, member)
+			.join(payment.reservation, reservation)
+			.where(payment.member.id.eq(memberId))
+			.orderBy(payment.paidAt.desc()).fetch();
+	}
+}

src/main/java/com/sudo/railo/payment/presentation/PaymentController.java

@@ -1,7 +1,11 @@
 package com.sudo.railo.payment.presentation;
 
+import java.util.List;
+
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
 import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -11,6 +15,8 @@
 import com.sudo.railo.payment.application.PaymentService;
 import com.sudo.railo.payment.application.dto.request.PaymentProcessAccountRequest;
 import com.sudo.railo.payment.application.dto.request.PaymentProcessCardRequest;
+import com.sudo.railo.payment.application.dto.response.PaymentCancelResponse;
+import com.sudo.railo.payment.application.dto.response.PaymentHistoryResponse;
 import com.sudo.railo.payment.application.dto.response.PaymentProcessResponse;
 import com.sudo.railo.payment.success.PaymentSuccess;
 
@@ -51,4 +57,25 @@ public SuccessResponse<PaymentProcessResponse> processPaymentViaBankAccount(
 
 		return SuccessResponse.of(PaymentSuccess.PAYMENT_PROCESS_SUCCESS, response);
 	}
+
+	@Operation(summary = "결제 취소", description = "완료된 결제를 취소 및 환불처리 합니다.")
+	@PostMapping("/{paymentKey}/cancel")
+	public SuccessResponse<PaymentCancelResponse> cancelPayment(@PathVariable String paymentKey,
+		@AuthenticationPrincipal UserDetails userDetails) {
+		String memberNo = userDetails.getUsername();
+		PaymentCancelResponse response = paymentService.cancelPayment(memberNo, paymentKey);
+
+		return SuccessResponse.of(PaymentSuccess.PAYMENT_CANCEL_SUCCESS, response);
+	}
+
+	@Operation(summary = "결제 내역 조회", description = "사용자의 결제 내역을 조회합니다.")
+	@GetMapping
+	public SuccessResponse<List<PaymentHistoryResponse>> getPaymentHistory(
+		@AuthenticationPrincipal UserDetails userDetails) {
+
+		String memberNo = userDetails.getUsername();
+		List<PaymentHistoryResponse> response = paymentService.getPaymentHistory(memberNo);
+
+		return SuccessResponse.of(PaymentSuccess.PAYMENT_HISTORY_SUCCESS, response);
+	}
 }