Develop

src/main/java/com/example/rels/domain/lecture/controller/LectureController.java

@@ -137,7 +137,7 @@ public EnrollmentResponse decideWaitingEnrollment(
 			@AuthenticationPrincipal AuthenticatedUser currentUser,
 			@Valid @RequestBody EnrollmentDecisionRequest request) {
 		AuthenticatedUser authenticatedUser = requireUser(currentUser);
-		return lectureService.decideWaitingEnrollment(lectureId, userId, authenticatedUser.userId(), authenticatedUser.role(), request);
+		return lectureService.decideWaitingEnrollment(lectureId, userId, authenticatedUser.role(), request);
 	}
 
 	@GetMapping("/enrollments/me")

src/main/java/com/example/rels/domain/lecture/dto/response/LectureSummaryResponse.java

@@ -20,6 +20,7 @@ public record LectureSummaryResponse(
 		String rejectionReason,
 		long enrolledCount,
 		long waitingCount,
+		String myEnrollmentStatus,
 		String lectureLocation,
 		LocalDate lectureDate,
 		LocalTime lectureTime,

src/main/java/com/example/rels/domain/lecture/repository/LectureEnrollmentRepository.java

@@ -32,6 +32,8 @@ Optional<LectureEnrollmentEntity> findFirstByLectureIdAndStatusOrderByRequestedA
 
 	List<LectureEnrollmentEntity> findAllByLectureId(Long lectureId);
 
+	List<LectureEnrollmentEntity> findAllByUserIdAndLectureIdIn(Long userId, Collection<Long> lectureIds);
+
 	@Modifying
 	@Transactional
 	void deleteByLectureId(Long lectureId);

src/main/java/com/example/rels/domain/lecture/service/LectureLifecycleHandler.java

@@ -68,28 +68,6 @@ public void promoteFirstWaitingUser(LectureEntity lecture, LocalDateTime now) {
         }
     }
 
-    public void promoteWaitingAfterDeadline(LectureEntity lecture, LocalDateTime now) {
-        if (lecture.getId() == null || lecture.getStatus() == LectureStatus.CLOSE) return;
-        if (!isAfterApplicationDeadline(lecture, now)) return;
-
-        int capacity = resolveTotalCapacity(lecture);
-        if (capacity <= 0) return;
-
-        List<LectureEnrollmentEntity> enrollments = lectureEnrollmentRepository.findAllByLectureId(lecture.getId());
-        long enrolledCount = enrollments.stream().filter(e -> e.getStatus() == EnrollmentStatus.ENROLLED).count();
-        if (enrolledCount >= capacity) return;
-
-        List<LectureEnrollmentEntity> waiting = sortByRequestedOrder(enrollments.stream()
-                .filter(e -> e.getStatus() == EnrollmentStatus.WAITING)
-                .toList());
-
-        for (LectureEnrollmentEntity enrollment : waiting) {
-            if (enrolledCount >= capacity) break;
-            enrollment.promoteToEnrolled();
-            enrolledCount++;
-        }
-    }
-
     public void refreshLectureLifecycle(LectureEntity lecture, LocalDateTime now) {
         if (lecture.getId() == null) {
             LocalDateTime lectureEndDateTime = lecture.getLectureEndDateTime();

src/main/java/com/example/rels/domain/lecture/service/LectureService.java

@@ -93,8 +93,9 @@ public Page<LectureSummaryResponse> getLectures(Pageable pageable, Long viewerId
 				? lectureRepository.findAllByApprovalStatusOrderByCreatedAtDesc(ApprovalStatus.APPROVED, pageable)
 				: lectureRepository.findVisibleToUser(ApprovalStatus.APPROVED, viewerId, pageable);
 		Map<Long, Map<EnrollmentStatus, Long>> enrollmentCountsByLectureId = getEnrollmentCountsByLectureIds(lectures.getContent());
+		Map<Long, String> myEnrollmentStatusByLectureId = getMyEnrollmentStatusByLectureIds(lectures.getContent(), viewerId);
 
-		return lectures.map(lecture -> toLectureSummary(lecture, enrollmentCountsByLectureId, viewerId));
+		return lectures.map(lecture -> toLectureSummary(lecture, enrollmentCountsByLectureId, myEnrollmentStatusByLectureId, viewerId));
 	}
 
 	@Transactional(readOnly = true)
@@ -103,7 +104,7 @@ public Page<LectureSummaryResponse> getPendingLectures(Role currentUserRole, Pag
 		Page<LectureEntity> lectures = lectureRepository.findAllByApprovalStatusOrderByCreatedAtDesc(ApprovalStatus.PENDING, pageable);
 		Map<Long, Map<EnrollmentStatus, Long>> enrollmentCountsByLectureId = getEnrollmentCountsByLectureIds(lectures.getContent());
 
-		return lectures.map(lecture -> toLectureSummary(lecture, enrollmentCountsByLectureId, null));
+		return lectures.map(lecture -> toLectureSummary(lecture, enrollmentCountsByLectureId, Map.of(), null));
 	}
 
 	@Transactional
@@ -171,7 +172,7 @@ public EnrollmentResponse enroll(Long lectureId, Long userId) {
 		// approvedAt·createdAt은 서버가 UTC로 찍은 값이라 한국 시간 벽시계로 옮겨야 16:20이 맞는다.
 		LocalDateTime applicationOpenReference = toSchoolTime(
 				lecture.getApprovedAt() != null ? lecture.getApprovedAt() : lecture.getCreatedAt());
-		timeValidator.validateApplicationTime(applicationOpenReference, lecture.getApplicationDeadline(), now);
+		timeValidator.validateApplicationTime(applicationOpenReference, now);
 		boolean isAfterApplicationDeadline = isAfterApplicationDeadline(lecture, now);
 
 		lifecycleHandler.refreshLectureLifecycle(lecture, now);
@@ -259,6 +260,13 @@ public EnrollmentResponse cancelEnrollment(Long lectureId, Long userId) {
 		}
 
 		lectureEnrollmentRepository.delete(enrollment);
+		lectureEnrollmentRepository.flush();
+
+		// 마감 전에 신청자 자리가 비면 대기 1번이 학년 규칙에 맞게 올라간다.
+		// 마감 뒤에는 자동 승급이 없고 학생회가 직접 수락·거절한다.
+		if (canceledStatus == EnrollmentStatus.ENROLLED && !isAfterApplicationDeadline(lecture, now)) {
+			lifecycleHandler.promoteFirstWaitingUser(lecture, now);
+		}
 
 		long enrolledCount = lectureEnrollmentRepository.countByLectureIdAndStatus(lectureId, EnrollmentStatus.ENROLLED);
 		long waitingCount = lectureEnrollmentRepository.countByLectureIdAndStatus(lectureId, EnrollmentStatus.WAITING);
@@ -314,6 +322,7 @@ private long countEnrolledInGrade(Long lectureId, Integer grade) {
 
 	private LectureSummaryResponse toLectureSummary(LectureEntity lecture,
 													Map<Long, Map<EnrollmentStatus, Long>> enrollmentCountsByLectureId,
+													Map<Long, String> myEnrollmentStatusByLectureId,
 													Long viewerId) {
 		if (lecture.getCreator() == null) {
 			throw new ResponseStatusException(HttpStatus.INTERNAL_SERVER_ERROR, "강의 생성자 정보가 없습니다.");
@@ -335,6 +344,7 @@ private LectureSummaryResponse toLectureSummary(LectureEntity lecture,
 				resolveRejectionReason(lecture, viewerId),
 				enrolledCount,
 				waitingCount,
+				myEnrollmentStatusByLectureId.get(lecture.getId()),
 				lecture.getLectureLocation(),
 				lecture.getLectureDate(),
 				lecture.getLectureTime(),
@@ -346,6 +356,21 @@ private LectureSummaryResponse toLectureSummary(LectureEntity lecture,
 		);
 	}
 
+	/**
+	 * 목록에 있는 강연들에 대해 보는 사람 본인의 신청 상태를 한 번에 읽는다.
+	 * 첫 화면이 "이미 신청했는지"를 알아야 신청 버튼을 잘못 열지 않는다.
+	 */
+	private Map<Long, String> getMyEnrollmentStatusByLectureIds(List<LectureEntity> lectures, Long viewerId) {
+		if (viewerId == null || lectures.isEmpty()) return Map.of();
+
+		List<Long> lectureIds = lectures.stream().map(LectureEntity::getId).toList();
+
+		return lectureEnrollmentRepository.findAllByUserIdAndLectureIdIn(viewerId, lectureIds).stream()
+				.collect(Collectors.toMap(
+						enrollment -> enrollment.getLecture().getId(),
+						enrollment -> enrollment.getStatus().name()));
+	}
+
 	private Map<Long, Map<EnrollmentStatus, Long>> getEnrollmentCountsByLectureIds(List<LectureEntity> lectures) {
 		if (lectures.isEmpty()) return Map.of();
 
@@ -495,10 +520,11 @@ private List<EnrollmentUserResponse> filterEnrollmentsByStatus(List<LectureEnrol
 	}
 
 	@Transactional
-	public EnrollmentResponse decideWaitingEnrollment(Long lectureId, Long enrollmentUserId, Long currentUserId,
-													  Role currentUserRole, EnrollmentDecisionRequest request) {
+	public EnrollmentResponse decideWaitingEnrollment(Long lectureId, Long enrollmentUserId, Role currentUserRole,
+															  EnrollmentDecisionRequest request) {
 		LectureEntity lecture = requireLecture(lectureId);
-		validateCreatorOrAdmin(lecture, currentUserId, currentUserRole);
+		// 대기자를 신청자로 올리는 판단은 학생회만 한다.
+		validateAdmin(currentUserRole);
 		LectureEnrollmentEntity enrollment = lectureEnrollmentRepository.findByLectureIdAndUserId(lectureId, enrollmentUserId)
 				.orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND, "대기 신청 내역이 없습니다."));
 		if (enrollment.getStatus() != EnrollmentStatus.WAITING) {
@@ -509,6 +535,11 @@ public EnrollmentResponse decideWaitingEnrollment(Long lectureId, Long enrollmen
 		long waitingCount = lectureEnrollmentRepository.countByLectureIdAndStatus(lectureId, EnrollmentStatus.WAITING);
 		if (request.approved()) {
 			enrollment.promoteToEnrolled();
+			// 마감 뒤에는 학생회가 올려 주는 것이 신청자가 느는 유일한 길이라,
+			// 여기서도 확정 기준(10명)을 다시 본다. 그러지 않으면 10명을 넘겨도 '개설 불확정'으로 남는다.
+			if (lecture.getStatus() != LectureStatus.CLOSE && enrolledCount + 1 >= CONFIRM_THRESHOLD) {
+				lecture.confirm();
+			}
 			return new EnrollmentResponse(lectureId, EnrollmentStatus.ENROLLED.name(), enrolledCount + 1, waitingCount - 1, enrollment.getRequestedAt());
 		}
 

src/main/java/com/example/rels/domain/lecture/service/LectureTimeValidator.java

@@ -26,7 +26,13 @@ public void validateApplicationDeadline(LocalDate lectureDate, LocalTime lecture
         }
     }
 
-    public void validateApplicationTime(LocalDateTime approvalTime, LocalDateTime deadline, LocalDateTime now) {
+    /**
+     * 신청이 열리는 시각만 본다. 승인한 날 16:20부터이고, 승인이 이미 16:20을 넘겼으면 다음 날 16:20부터다.
+     *
+     * 마감 시각은 여기서 막지 않는다. 마감 뒤에도 대기 신청은 받기 때문이다.
+     * 마감 뒤에 들어온 신청을 대기로 돌리는 일은 LectureService.enroll이 맡는다.
+     */
+    public void validateApplicationTime(LocalDateTime approvalTime, LocalDateTime now) {
         LocalDateTime openTime = approvalTime.toLocalDate().atTime(16, 20);
         if (approvalTime.isAfter(openTime)) {
             openTime = openTime.plusDays(1);
@@ -38,12 +44,5 @@ public void validateApplicationTime(LocalDateTime approvalTime, LocalDateTime de
                     "수강 신청은 " + openTime.toLocalDate() + " 오후 4시 20분부터 가능합니다."
             );
         }
-
-        if (deadline != null && now.isAfter(deadline)) {
-            throw new ResponseStatusException(
-                    HttpStatus.FORBIDDEN,
-                    "수강 신청 마감 시간이 지났습니다."
-            );
-        }
     }
 }