feat: mock 데이터 lessonParticipant 추가

Author: ense333

src/main/java/com/threestar/trainus/global/config/MockDataInitializer.java

@@ -20,6 +20,8 @@
 import com.threestar.trainus.domain.coupon.user.repository.UserCouponRepository;
 import com.threestar.trainus.domain.lesson.teacher.entity.Category;
 import com.threestar.trainus.domain.lesson.teacher.entity.Lesson;
+import com.threestar.trainus.domain.lesson.teacher.entity.LessonParticipant;
+import com.threestar.trainus.domain.lesson.teacher.repository.LessonParticipantRepository;
 import com.threestar.trainus.domain.lesson.teacher.repository.LessonRepository;
 import com.threestar.trainus.domain.metadata.entity.ProfileMetadata;
 import com.threestar.trainus.domain.metadata.mapper.ProfileMetadataMapper;
@@ -50,6 +52,7 @@ public class MockDataInitializer implements CommandLineRunner {
 	private final PasswordEncoder passwordEncoder;
 	private final CouponRepository couponRepository;
 	private final UserCouponRepository userCouponRepository;
+	private final LessonParticipantRepository lessonParticipantRepository;
 
 	private final Random random = new Random();
 
@@ -81,6 +84,9 @@ public void run(String... args) throws Exception {
 		// 6. 유저쿠폰 생성 (사용자들이 쿠폰 발급받은 데이터)
 		createUserCoupons(students, coupons);
 
+		// 7. 레슨 참여자 생성
+		createLessonParticipants(students, lessons);
+
 		log.info("Mock 데이터 생성 완료!");
 		log.info("생성된 데이터: 강사 {}명, 수강생 {}명, 레슨 {}개",
 			instructors.size(), students.size(), lessons.size());
@@ -364,6 +370,37 @@ private void createUserCoupons(List<User> students, List<Coupon> coupons) {
 		log.info("유저쿠폰 {}개 생성 완료", userCoupons.size());
 	}
 
+	// lessonParticipant 테이블에 데이터 삽입
+	private void createLessonParticipants(List<User> students, List<Lesson> lessons) {
+		List<LessonParticipant> participants = new ArrayList<>();
+		Random rand = new Random();
+		for (User student : students) {
+			// 각 학생당 1~4개의 레슨 참여
+			int joinCount = rand.nextInt(4) + 1;
+
+			Set<Long> joinedLessonIds = new HashSet<>();
+
+			for (int i = 0; i < joinCount; i++) {
+				Lesson lesson = lessons.get(rand.nextInt(lessons.size()));
+
+				// 중복 참여 방지
+				if (joinedLessonIds.contains(lesson.getId()))
+					continue;
+				joinedLessonIds.add(lesson.getId());
+
+				LessonParticipant participant = LessonParticipant.builder()
+					.lesson(lesson)
+					.user(student)
+					.build();
+
+				participants.add(participant);
+			}
+		}
+
+		lessonParticipantRepository.saveAll(participants);
+		log.info("레슨 참여자 {}명 생성 완료", participants.size());
+	}
+
 	// 최소 주문 금액 생성 (10000-50000원, 5000원 단위)
 	private Integer generateMinOrderPrice() {
 		return (random.nextInt(9) + 2) * 5000; // 10000-50000원