feat: 지원 현황 미리보기 API 추가

src/main/java/com/example/solidconnection/application/controller/ApplicationController.java

@@ -1,5 +1,6 @@
 package com.example.solidconnection.application.controller;
 
+import com.example.solidconnection.application.dto.ApplicationPreviewResponse;
 import com.example.solidconnection.application.dto.ApplicationSubmissionResponse;
 import com.example.solidconnection.application.dto.ApplicationsResponse;
 import com.example.solidconnection.application.dto.ApplyRequest;
@@ -37,6 +38,14 @@ public ResponseEntity<ApplicationSubmissionResponse> apply(
                 .body(applicationSubmissionResponse);
     }
 
+    @GetMapping("/preview")
+    public ResponseEntity<ApplicationPreviewResponse> getApplicationPreview(
+            @AuthorizedUser long siteUserId
+    ) {
+        ApplicationPreviewResponse result = applicationQueryService.getApplicantUniversityPreviews(siteUserId);
+        return ResponseEntity.ok(result);
+    }
+
     // @RequireRoleAccess(roles = {Role.ADMIN}) // todo : 추후 어드민 페이지에서 권한 변경 기능 추가 필요
     @GetMapping
     public ResponseEntity<ApplicationsResponse> getApplicants(

src/main/java/com/example/solidconnection/application/dto/ApplicationPreviewResponse.java

@@ -0,0 +1,8 @@
+package com.example.solidconnection.application.dto;
+
+import java.util.List;
+
+public record ApplicationPreviewResponse(
+        long totalUniversityCount,
+        List<ApplicationUniversityPreviewResponse> universities) {
+}

src/main/java/com/example/solidconnection/application/dto/ApplicationUniversityPreviewResponse.java

@@ -0,0 +1,25 @@
+package com.example.solidconnection.application.dto;
+
+import com.example.solidconnection.university.domain.UnivApplyInfo;
+
+public record ApplicationUniversityPreviewResponse(
+        long id,
+        String koreanName,
+        Integer studentCapacity,
+        String region,
+        String country,
+        String logoImageUrl,
+        String backgroundImageUrl) {
+
+    public static ApplicationUniversityPreviewResponse from(UnivApplyInfo univApplyInfo) {
+        return new ApplicationUniversityPreviewResponse(
+                univApplyInfo.getId(),
+                univApplyInfo.getKoreanName(),
+                univApplyInfo.getStudentCapacity(),
+                univApplyInfo.getUniversity().getRegion().getKoreanName(),
+                univApplyInfo.getUniversity().getCountry().getKoreanName(),
+                univApplyInfo.getUniversity().getLogoImageUrl(),
+                univApplyInfo.getUniversity().getBackgroundImageUrl()
+        );
+    }
+}

src/main/java/com/example/solidconnection/application/repository/ApplicationRepository.java

@@ -3,6 +3,7 @@
 import static com.example.solidconnection.common.exception.ErrorCode.APPLICATION_NOT_FOUND;
 
 import com.example.solidconnection.application.domain.Application;
+import com.example.solidconnection.application.dto.ApplicationUniversityPreviewResponse;
 import com.example.solidconnection.common.VerifyStatus;
 import com.example.solidconnection.common.exception.CustomException;
 import java.util.List;
@@ -29,6 +30,38 @@ List<Application> findAllByUnivApplyInfoIds(
             @Param("status") VerifyStatus status,
             @Param("termId") long termId);
 
+    @Query("""
+           SELECT new com.example.solidconnection.application.dto.ApplicationUniversityPreviewResponse(
+               uai.id,
+               uai.koreanName,
+               uai.studentCapacity,
+               region.koreanName,
+               country.koreanName,
+               university.logoImageUrl,
+               university.backgroundImageUrl
+           )
+           FROM UnivApplyInfo uai
+           JOIN uai.university university
+           JOIN university.region region
+           JOIN university.country country
+           WHERE uai.termId = :termId
+               AND uai.homeUniversity.id = :homeUniversityId
+               AND EXISTS (
+                   SELECT application.id
+                   FROM Application application
+                   JOIN application.choices choice
+                   WHERE choice.univApplyInfoId = uai.id
+                       AND application.verifyStatus = :status
+                       AND application.termId = :termId
+                       AND application.isDelete = false
+               )
+           ORDER BY uai.koreanName
+           """)
+    List<ApplicationUniversityPreviewResponse> findApplicantUniversityPreviews(
+            @Param("status") VerifyStatus status,
+            @Param("termId") long termId,
+            @Param("homeUniversityId") long homeUniversityId);
+
     Optional<Application> findTopBySiteUserIdAndTermIdAndIsDeleteFalseOrderByIdDesc(long siteUserId, long termId);
 
     default Application getApplicationBySiteUserIdAndTermId(long siteUserId, long termId) {

src/main/java/com/example/solidconnection/application/service/ApplicationQueryService.java

@@ -2,11 +2,13 @@
 
 import static com.example.solidconnection.common.exception.ErrorCode.APPLICATION_NOT_APPROVED;
 import static com.example.solidconnection.common.exception.ErrorCode.CURRENT_TERM_NOT_FOUND;
+import static com.example.solidconnection.common.exception.ErrorCode.SCHOOL_EMAIL_NOT_VERIFIED;
 import static com.example.solidconnection.common.exception.ErrorCode.USER_NOT_FOUND;
 
 import com.example.solidconnection.application.domain.Application;
 import com.example.solidconnection.application.domain.ApplicationChoice;
 import com.example.solidconnection.application.dto.ApplicantsResponse;
+import com.example.solidconnection.application.dto.ApplicationPreviewResponse;
 import com.example.solidconnection.application.dto.ApplicationsResponse;
 import com.example.solidconnection.application.repository.ApplicationRepository;
 import com.example.solidconnection.common.VerifyStatus;
@@ -41,6 +43,27 @@ public class ApplicationQueryService {
     private final TermRepository termRepository;
     private final HomeUniversityRepository homeUniversityRepository;
 
+    @Transactional(readOnly = true)
+    public ApplicationPreviewResponse getApplicantUniversityPreviews(long siteUserId) {
+        SiteUser siteUser = siteUserRepository.findById(siteUserId)
+                .orElseThrow(() -> new CustomException(USER_NOT_FOUND));
+
+        if (siteUser.getHomeUniversityId() == null) {
+            throw new CustomException(SCHOOL_EMAIL_NOT_VERIFIED);
+        }
+
+        Term term = termRepository.findByIsCurrentTrue()
+                .orElseThrow(() -> new CustomException(CURRENT_TERM_NOT_FOUND));
+
+        return new ApplicationPreviewResponse(
+                univApplyInfoRepository.countByTermIdAndHomeUniversityId(term.getId(), siteUser.getHomeUniversityId()),
+                applicationRepository.findApplicantUniversityPreviews(
+                        VerifyStatus.APPROVED,
+                        term.getId(),
+                        siteUser.getHomeUniversityId())
+        );
+    }
+
     @Transactional(readOnly = true)
     public ApplicationsResponse getApplicants(long siteUserId, String regionCode, String keyword) {
         SiteUser siteUser = siteUserRepository.findById(siteUserId)

src/main/java/com/example/solidconnection/university/repository/UnivApplyInfoRepository.java

@@ -71,6 +71,8 @@ default UnivApplyInfo getUnivApplyInfoById(Long id) {
 
     boolean existsByHomeUniversityId(Long homeUniversityId);
 
+    long countByTermIdAndHomeUniversityId(long termId, long homeUniversityId);
+
     @Query("""
            SELECT uai.id
            FROM UnivApplyInfo uai

src/test/java/com/example/solidconnection/application/service/ApplicationQueryServiceTest.java

@@ -1,14 +1,19 @@
 package com.example.solidconnection.application.service;
 
+import static com.example.solidconnection.common.exception.ErrorCode.SCHOOL_EMAIL_NOT_VERIFIED;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 import com.example.solidconnection.application.domain.Application;
 import com.example.solidconnection.application.dto.ApplicantResponse;
 import com.example.solidconnection.application.dto.ApplicantsResponse;
+import com.example.solidconnection.application.dto.ApplicationPreviewResponse;
+import com.example.solidconnection.application.dto.ApplicationUniversityPreviewResponse;
 import com.example.solidconnection.application.dto.ApplicationsResponse;
 import com.example.solidconnection.application.fixture.ApplicationFixture;
 import com.example.solidconnection.application.repository.ApplicationRepository;
 import com.example.solidconnection.common.VerifyStatus;
+import com.example.solidconnection.common.exception.CustomException;
 import com.example.solidconnection.location.region.fixture.RegionFixture;
 import com.example.solidconnection.score.domain.GpaScore;
 import com.example.solidconnection.score.domain.LanguageTestScore;
@@ -20,7 +25,9 @@
 import com.example.solidconnection.term.domain.Term;
 import com.example.solidconnection.term.fixture.TermFixture;
 import com.example.solidconnection.university.domain.UnivApplyInfo;
+import com.example.solidconnection.university.fixture.HomeUniversityFixture;
 import com.example.solidconnection.university.fixture.UnivApplyInfoFixture;
+import com.example.solidconnection.university.fixture.UnivApplyInfoFixtureBuilder;
 import java.util.List;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
@@ -47,6 +54,12 @@ class ApplicationQueryServiceTest {
     @Autowired
     private UnivApplyInfoFixture univApplyInfoFixture;
 
+    @Autowired
+    private UnivApplyInfoFixtureBuilder univApplyInfoFixtureBuilder;
+
+    @Autowired
+    private HomeUniversityFixture homeUniversityFixture;
+
     @Autowired
     private GpaScoreFixture gpaScoreFixture;
 
@@ -98,6 +111,114 @@ void setUp() {
         서던덴마크대학교_지원_정보 = univApplyInfoFixture.서던덴마크대학교_지원_정보(term.getId());
     }
 
+    @Nested
+    @DisplayName("지원 현황 미리보기 조회")
+    class 지원_현황_미리보기_조회_테스트 {
+
+        @Test
+        void 자신의_모교에_속한_지원_대학만_중복_없이_조회한다() {
+            // given
+            SiteUser inhaUniversityUser = siteUserFixture.국내_대학_정보_소지_사용자(
+                    괌대학_A_지원_정보.getHomeUniversity().getId());
+            applicationFixture.지원서(
+                    user1, "nickname1", term.getId(),
+                    gpaScore1.getGpa(), languageTestScore1.getLanguageTest(),
+                    List.of(괌대학_A_지원_정보.getId(), 버지니아공과대학_지원_정보.getId())
+            );
+            applicationFixture.지원서(
+                    user2, "nickname2", term.getId(),
+                    gpaScore2.getGpa(), languageTestScore2.getLanguageTest(),
+                    List.of(괌대학_A_지원_정보.getId())
+            );
+            UnivApplyInfo 인천대학교_전용_지원_정보 = univApplyInfoFixtureBuilder.univApplyInfo()
+                    .termId(term.getId())
+                    .koreanName("인천대학교 전용 교환 대학")
+                    .university(서던덴마크대학교_지원_정보.getUniversity())
+                    .homeUniversity(homeUniversityFixture.인천대학교())
+                    .create();
+            applicationFixture.지원서(
+                    user3, "nickname3", term.getId(),
+                    gpaScore3.getGpa(), languageTestScore3.getLanguageTest(),
+                    List.of(인천대학교_전용_지원_정보.getId())
+            );
+            Application deletedApplication = applicationFixture.지원서(
+                    user3, "nickname3", term.getId(),
+                    gpaScore3.getGpa(), languageTestScore3.getLanguageTest(),
+                    List.of(서던덴마크대학교_지원_정보.getId())
+            );
+            deletedApplication.setIsDeleteTrue();
+            applicationRepository.save(deletedApplication);
+            UnivApplyInfo 승인_대기_지원_정보 = univApplyInfoFixtureBuilder.univApplyInfo()
+                    .termId(term.getId())
+                    .koreanName("승인 대기 교환 대학")
+                    .university(서던덴마크대학교_지원_정보.getUniversity())
+                    .homeUniversity(괌대학_A_지원_정보.getHomeUniversity())
+                    .create();
+            Application pendingApplication = applicationFixture.지원서(
+                    user1, "pending-nickname", term.getId(),
+                    gpaScore1.getGpa(), languageTestScore1.getLanguageTest(),
+                    List.of(승인_대기_지원_정보.getId())
+            );
+            pendingApplication.setVerifyStatus(VerifyStatus.PENDING);
+            applicationRepository.save(pendingApplication);
+            UnivApplyInfo 승인_거절_지원_정보 = univApplyInfoFixtureBuilder.univApplyInfo()
+                    .termId(term.getId())
+                    .koreanName("승인 거절 교환 대학")
+                    .university(서던덴마크대학교_지원_정보.getUniversity())
+                    .homeUniversity(괌대학_A_지원_정보.getHomeUniversity())
+                    .create();
+            Application rejectedApplication = applicationFixture.지원서(
+                    user2, "rejected-nickname", term.getId(),
+                    gpaScore2.getGpa(), languageTestScore2.getLanguageTest(),
+                    List.of(승인_거절_지원_정보.getId())
+            );
+            rejectedApplication.setVerifyStatus(VerifyStatus.REJECTED);
+            applicationRepository.save(rejectedApplication);
+
+            // when
+            ApplicationPreviewResponse response = applicationQueryService.getApplicantUniversityPreviews(
+                    inhaUniversityUser.getId());
+
+            // then
+            assertThat(response.totalUniversityCount()).isEqualTo(5);
+            assertThat(response.universities()).containsExactly(
+                    ApplicationUniversityPreviewResponse.from(괌대학_A_지원_정보),
+                    ApplicationUniversityPreviewResponse.from(버지니아공과대학_지원_정보)
+            );
+        }
+
+        @Test
+        void 성적과_지원서를_제출하지_않은_로그인_사용자도_미리보기를_조회할_수_있다() {
+            // given
+            SiteUser signedInUserWithoutScores = siteUserFixture.국내_대학_정보_소지_사용자(
+                    괌대학_A_지원_정보.getHomeUniversity().getId());
+            applicationFixture.지원서(
+                    user2, "nickname2", term.getId(),
+                    gpaScore2.getGpa(), languageTestScore2.getLanguageTest(),
+                    List.of(괌대학_A_지원_정보.getId())
+            );
+
+            // when
+            ApplicationPreviewResponse response = applicationQueryService.getApplicantUniversityPreviews(
+                    signedInUserWithoutScores.getId());
+
+            // then
+            assertThat(response.totalUniversityCount()).isEqualTo(3);
+            assertThat(response.universities()).containsExactly(
+                    ApplicationUniversityPreviewResponse.from(괌대학_A_지원_정보)
+            );
+        }
+
+        @Test
+        void 모교가_등록되지_않은_사용자는_미리보기를_조회할_수_없다() {
+            // when
+            // then
+            assertThatThrownBy(() -> applicationQueryService.getApplicantUniversityPreviews(user1.getId()))
+                    .isInstanceOf(CustomException.class)
+                    .hasMessage(SCHOOL_EMAIL_NOT_VERIFIED.getMessage());
+        }
+    }
+
     @Nested
     class 지원자_목록_조회_테스트 {