dev -> prd

layer-admin/src/main/java/org/layer/admin/retrospect/controller/AdminRetrospectController.java

@@ -6,6 +6,7 @@
 import org.layer.admin.retrospect.controller.dto.CumulativeRetrospectCountResponse;
 import org.layer.admin.retrospect.controller.dto.MeaningfulRetrospectMemberResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectCompletionRateResponse;
+import org.layer.admin.retrospect.controller.dto.RetrospectOverviewResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectRetentionResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectStayTimeResponse;
 import org.layer.admin.retrospect.service.AdminRetrospectService;
@@ -23,6 +24,15 @@ public class AdminRetrospectController {
 
 	private final AdminRetrospectService adminRetrospectService;
 
+	@GetMapping("/admin/retrospect/overview")
+	public ResponseEntity<RetrospectOverviewResponse> getRetrospectOverview(
+		@RequestParam(name = "startDate") LocalDateTime startDate,
+		@RequestParam(name = "endDate") LocalDateTime endDate) {
+
+		RetrospectOverviewResponse response = adminRetrospectService.getRetrospectOverview(startDate, endDate);
+		return ResponseEntity.ok().body(response);
+	}
+
 	@GetMapping("/admin/retrospect/stay-time")
 	public ResponseEntity<List<RetrospectStayTimeResponse>> getAllRetrospectStayTime(
 		@RequestParam(name = "startDate") LocalDateTime startDate,

layer-admin/src/main/java/org/layer/admin/retrospect/controller/dto/RetrospectOverviewResponse.java

@@ -0,0 +1,9 @@
+package org.layer.admin.retrospect.controller.dto;
+
+public record RetrospectOverviewResponse(
+	long createdRetrospectCount,
+	long completedRetrospectCount,
+	double averageCompletionRate,
+	double averageRetrospectLength
+) {
+}

layer-admin/src/main/java/org/layer/admin/retrospect/repository/AdminRetrospectAnswerRepository.java

@@ -44,6 +44,17 @@ List<RetrospectAnswerCompletionDto> findRetrospectAnswerCompletionStatsBetween(
 		@Param("start") LocalDateTime startTime,
 		@Param("end") LocalDateTime endTime);
 
+	@Query("""
+		SELECT COALESCE(AVG(LENGTH(a.answerContent)), 0)
+		FROM AdminRetrospectAnswerHistory a
+		WHERE a.answerEndTime IS NOT NULL
+		  AND a.answerEndTime BETWEEN :startTime AND :endTime
+	""")
+	double findAverageRetrospectLengthBetween(
+		@Param("startTime") LocalDateTime startTime,
+		@Param("endTime") LocalDateTime endTime
+	);
+
 	// 엣지 케이스로 답변 종료시간이 없는 경우도 있을 수 있기에 필터링한다.
 	List<AdminRetrospectAnswerHistory> findAllByEventTimeBetweenAndAnswerEndTimeIsNotNull(
 		LocalDateTime startTime, LocalDateTime endTime);

layer-admin/src/main/java/org/layer/admin/retrospect/repository/AdminRetrospectRepository.java

@@ -20,4 +20,17 @@ List<Long> findProceedingSpacesByMember(
 		@Param("startDate") LocalDateTime startDate,
 		@Param("endDate") LocalDateTime endDate
 	);
+
+	Long countAllByCreatedAtBetween(LocalDateTime startDate, LocalDateTime endDate);
+
+	@Query("""
+		SELECT COUNT(r)
+		FROM AdminRetrospect r
+		WHERE r.retrospectStatus = 'DONE'
+		  AND r.updatedAt BETWEEN :startDate AND :endDate
+	""")
+	Long countCompletedRetrospectBetween(
+		@Param("startDate") LocalDateTime startDate,
+		@Param("endDate") LocalDateTime endDate
+	);
 }

layer-admin/src/main/java/org/layer/admin/retrospect/service/AdminRetrospectService.java

@@ -20,6 +20,7 @@
 import org.layer.admin.retrospect.controller.dto.MeaningfulRetrospectMemberResponse;
 import org.layer.admin.retrospect.controller.dto.ProceedingRetrospectCTRAverageResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectCompletionRateResponse;
+import org.layer.admin.retrospect.controller.dto.RetrospectOverviewResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectRetentionResponse;
 import org.layer.admin.retrospect.controller.dto.RetrospectStayTimeResponse;
 import org.layer.admin.retrospect.entity.AdminRetrospect;
@@ -65,6 +66,25 @@ public class AdminRetrospectService {
 	private final AdminRetrospectRepository retrospectRepository;
 	private final AdminMemberSpaceRelationRepository memberSpaceRelationRepository;
 
+	public RetrospectOverviewResponse getRetrospectOverview(LocalDateTime startDate, LocalDateTime endDate) {
+		long createdRetrospectCount = retrospectRepository.countAllByCreatedAtBetween(startDate, endDate);
+		long completedRetrospectCount = retrospectRepository.countCompletedRetrospectBetween(startDate, endDate);
+
+		double averageCompletionRate = createdRetrospectCount == 0
+			? 0.0
+			: (completedRetrospectCount / (double)createdRetrospectCount) * 100.0;
+
+		double averageRetrospectLength = adminRetrospectAnswerRepository.findAverageRetrospectLengthBetween(
+			startDate, endDate);
+
+		return new RetrospectOverviewResponse(
+			createdRetrospectCount,
+			completedRetrospectCount,
+			averageCompletionRate,
+			averageRetrospectLength
+		);
+	}
+
 	public MeaningfulRetrospectMemberResponse getAllMeaningfulRetrospect(
 		LocalDateTime startTime, LocalDateTime endTime, int retrospectLength, int retrospectCount) {
 		List<Long> meaningfulMemberIds = adminRetrospectAnswerRepository.findMeaningfulMemberIds(