[Refactor]면접 예약 날짜 변경 기능 추가

src/main/java/dmu/dasom/api/domain/applicant/repository/ApplicantRepository.java

@@ -25,4 +25,5 @@ public interface ApplicantRepository extends JpaRepository<Applicant, Long> {
     Optional<Applicant> findByStudentNoAndContactEndsWith(@Param("studentNo") String studentNo,
                                                           @Param("contactLastDigits") String contactLastDigits);
 
+    Optional<Applicant> findByStudentNoAndEmail(String studentNo, String email);
 }

src/main/java/dmu/dasom/api/domain/common/exception/ErrorCode.java

@@ -34,9 +34,11 @@ public enum ErrorCode {
     SLOT_FULL(400, "C025", "해당 슬롯이 가득 찼습니다."),
     RESERVATION_NOT_FOUND(400, "C026", "예약을 찾을 수 없습니다."),
     SLOT_NOT_ACTIVE(400, "C027", "해당 슬롯이 비활성화 되었습니다."),
-    FILE_ENCODE_FAIL(400, "C028", "파일 인코딩에 실패하였습니다."),
-    RECRUITMENT_NOT_ACTIVE(400, "C029", "모집 기간이 아닙니다."),
-    NOT_FOUND_PARTICIPANT(400, "C030", "참가자를 찾을 수 없습니다.")
+    SLOT_UNAVAILABLE(400, "C028", "해당 슬롯을 예약할 수 없습니다."),
+    FILE_ENCODE_FAIL(400, "C029", "파일 인코딩에 실패하였습니다."),
+    RECRUITMENT_NOT_ACTIVE(400, "C030", "모집 기간이 아닙니다."),
+    NOT_FOUND_PARTICIPANT(400, "C031", "참가자를 찾을 수 없습니다."),
+    VERIFICATION_CODE_NOT_VALID(400, "C032", "인증 코드가 유효하지 않습니다.")
     ;
 
     private final int status;

src/main/java/dmu/dasom/api/domain/email/service/EmailService.java

@@ -0,0 +1,96 @@
+package dmu.dasom.api.domain.email.service;
+
+import dmu.dasom.api.domain.common.exception.CustomException;
+import dmu.dasom.api.domain.common.exception.ErrorCode;
+import dmu.dasom.api.domain.google.enums.MailType;
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.MimeMessage;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.stereotype.Service;
+import org.thymeleaf.TemplateEngine;
+import org.thymeleaf.context.Context;
+
+@RequiredArgsConstructor
+@Service
+public class EmailService {
+
+    private final TemplateEngine templateEngine;
+    private final JavaMailSender javaMailSender;
+
+    @Value("${spring.mail.username}")
+    private String from;
+
+    public void sendVerificationEmail(String to, String name, String code) throws MessagingException {
+        String subject = "DASOM 면접 시간 변경을 위한 이메일 인증 코드 안내";
+        String emailContent = "요청하신 인증 코드는 다음과 같습니다.<br>" +
+            "인증 코드: <strong>" + code + "</strong><br>" +
+            "해당 코드를 3분 내에 입력하여 인증을 완료해주세요.";
+
+        Context context = new Context();
+        context.setVariable("name", name);
+        context.setVariable("emailContent", emailContent);
+        context.setVariable("buttonUrl", "https://dmu-dasom.or.kr"); // Or some other relevant link
+        context.setVariable("buttonText", "다솜 홈페이지로 이동");
+
+        String htmlBody = templateEngine.process("email-template", context);
+        send(to, subject, htmlBody);
+    }
+
+    public void sendEmail(String to, String name, MailType mailType) throws MessagingException {
+        if (mailType == null){
+            throw new CustomException(ErrorCode.MAIL_TYPE_NOT_VALID);
+        }
+
+        // 메일 제목 및 템플릿 설정
+        String subject;
+        String emailContent;
+        String buttonUrl = "https://dmu-dasom.or.kr/recruit/result";
+        String buttonText;
+
+        switch (mailType) {
+            case DOCUMENT_RESULT -> {
+                subject = "동양미래대학교 컴퓨터소프트웨어공학과 전공 동아리 DASOM 서류 결과 안내";
+                emailContent = "먼저 다솜 34기에 많은 관심을 두고 지원해 주셔서 감사드리며,<br>" +
+                        "내부 서류 평가 결과 및 추후 일정에 관해 안내해드리고자 이메일을 발송하게 되었습니다.<br>" +
+                        "서류 전형 결과는 아래 버튼 혹은 홈페이지를 통해 확인이 가능합니다.";
+                buttonText = "서류 결과 확인하기";
+            }
+            case FINAL_RESULT -> {
+                subject = "동양미래대학교 컴퓨터소프트웨어공학과 전공 동아리 DASOM 최종 면접 결과 안내";
+                emailContent = "먼저 다솜 34기에 많은 관심을 두고 지원해 주셔서 감사드리며,<br>" +
+                        "최종 면접 결과 및 추후 일정에 관해 안내해드리고자 이메일을 발송하게 되었습니다.<br>" +
+                        "최종 면접 결과는 아래 버튼 혹은 홈페이지를 통해 확인이 가능합니다.";
+                buttonText = "최종 결과 확인하기";
+            }
+            default -> throw new IllegalStateException("Unexpected value: " + mailType);
+        }
+
+        // HTML 템플릿에 전달할 데이터 설정
+        Context context = new Context();
+        context.setVariable("name", name); // 지원자 이름 전달
+        context.setVariable("emailContent", emailContent); // 이메일 내용 전달
+        context.setVariable("buttonUrl", buttonUrl); // 버튼 링크 전달
+        context.setVariable("buttonText", buttonText);
+
+        // HTML 템플릿 처리
+        String htmlBody = templateEngine.process("email-template", context);
+        send(to, subject, htmlBody);
+    }
+
+    private void send(String to, String subject, String htmlBody) throws MessagingException {
+        MimeMessage message = javaMailSender.createMimeMessage();
+        MimeMessageHelper helper = new MimeMessageHelper(message, true, "UTF-8");
+
+        helper.setTo(to);
+        helper.setSubject(subject);
+        helper.setText(htmlBody, true);
+        helper.setFrom((from != null && !from.isEmpty()) ? from : "[email protected]");
+
+        message.setContent(htmlBody, "text/html; charset=utf-8");
+
+        javaMailSender.send(message);
+    }
+}

src/main/java/dmu/dasom/api/domain/google/enums/MailType.java

@@ -2,5 +2,6 @@
 
 public enum MailType {
     DOCUMENT_RESULT, // 서류 합격
-    FINAL_RESULT // 최종 합격
+    FINAL_RESULT, // 최종 합격
+    VERIFICATION // 이메일 인증
 }

src/main/java/dmu/dasom/api/domain/interview/controller/InterviewController.java

@@ -0,0 +1,59 @@
+package dmu.dasom.api.domain.interview.controller;
+
+import dmu.dasom.api.domain.applicant.entity.Applicant;
+import dmu.dasom.api.domain.applicant.repository.ApplicantRepository;
+import dmu.dasom.api.domain.common.exception.CustomException;
+import dmu.dasom.api.domain.common.exception.ErrorCode;
+import dmu.dasom.api.domain.email.service.EmailService;
+import dmu.dasom.api.domain.interview.dto.InterviewReservationModifyRequestDto;
+import dmu.dasom.api.domain.interview.dto.VerificationCodeRequestDto;
+import dmu.dasom.api.domain.interview.service.InterviewService;
+import dmu.dasom.api.global.util.VerificationCodeManager;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import jakarta.mail.MessagingException;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import dmu.dasom.api.domain.interview.dto.InterviewReservationApplicantResponseDto;
+
+@Tag(name = "Interview", description = "면접 관련 API")
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/api/interview")
+public class InterviewController {
+
+    private final InterviewService interviewService;
+    private final ApplicantRepository applicantRepository;
+    private final VerificationCodeManager verificationCodeManager;
+    private final EmailService emailService;
+
+    @Operation(summary = "면접 예약 수정을 위한 인증 코드 발송", description = "지원자의 학번을 받아 이메일로 인증 코드를 발송합니다.")
+    @PostMapping("/send-verification")
+    public ResponseEntity<Void> sendVerificationCode(@Valid @RequestBody VerificationCodeRequestDto request) throws MessagingException {
+        Applicant applicant = applicantRepository.findByStudentNo(request.getStudentNo())
+                .orElseThrow(() -> new CustomException(ErrorCode.APPLICANT_NOT_FOUND));
+
+        String code = verificationCodeManager.generateAndStoreCode(applicant.getStudentNo());
+        emailService.sendVerificationEmail(applicant.getEmail(), applicant.getName(), code);
+
+        return ResponseEntity.ok().build();
+    }
+
+    @Operation(summary = "면접 예약 수정", description = "이메일로 발송된 인증 코드를 통해 인증 후, 면접 날짜 및 시간을 수정합니다.")
+    @PutMapping("/reservation/modify")
+    public ResponseEntity<Void> modifyInterviewReservation(@Valid @RequestBody InterviewReservationModifyRequestDto request) {
+        interviewService.modifyInterviewReservation(request);
+        return ResponseEntity.ok().build();
+    }
+
+    @Operation(summary = "모든 면접 지원자 목록 조회", description = "모든 면접 지원자의 상세 정보와 예약 정보를 조회합니다.")
+    @GetMapping("/applicants")
+    public ResponseEntity<List<InterviewReservationApplicantResponseDto>> getAllInterviewApplicants() {
+        List<InterviewReservationApplicantResponseDto> applicants = interviewService.getAllInterviewApplicants();
+        return ResponseEntity.ok(applicants);
+    }
+}

src/main/java/dmu/dasom/api/domain/interview/dto/InterviewReservationModifyRequestDto.java

@@ -0,0 +1,37 @@
+package dmu.dasom.api.domain.interview.dto;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+import jakarta.validation.constraints.Email;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Pattern;
+import jakarta.validation.constraints.Size;
+import lombok.*;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+@Builder
+@Schema(name = "InterviewReservationModifyRequestDto", description = "면접 예약 수정 요청 DTO")
+public class InterviewReservationModifyRequestDto {
+
+    @NotNull(message = "학번은 필수 값입니다.")
+    @Pattern(regexp = "^[0-9]{8}$", message = "학번은 8자리 숫자로 구성되어야 합니다.")
+    @Size(min = 8, max = 8)
+    @Schema(description = "지원자 학번", example = "20250001")
+    private String studentNo;
+
+    @NotNull(message = "이메일은 필수 값입니다.")
+    @Email(message = "유효한 이메일 주소를 입력해주세요.")
+    @Size(max = 64)
+    @Schema(description = "지원자 이메일", example = "[email protected]")
+    private String email;
+
+    @NotNull(message = "새로운 슬롯 ID는 필수 값입니다.")
+    @Schema(description = "새롭게 예약할 면접 슬롯의 ID", example = "2")
+    private Long newSlotId;
+
+    @NotNull(message = "인증 코드는 필수 값입니다.")
+    @Schema(description = "이메일로 발송된 6자리 인증 코드", example = "123456")
+    private String verificationCode;
+}

src/main/java/dmu/dasom/api/domain/interview/dto/VerificationCodeRequestDto.java

@@ -0,0 +1,17 @@
+package dmu.dasom.api.domain.interview.dto;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Pattern;
+import jakarta.validation.constraints.Size;
+import lombok.Getter;
+
+@Getter
+public class VerificationCodeRequestDto {
+
+    @NotNull(message = "학번은 필수 값입니다.")
+    @Pattern(regexp = "^[0-9]{8}$", message = "학번은 8자리 숫자로 구성되어야 합니다.")
+    @Size(min = 8, max = 8)
+    @Schema(description = "지원자 학번", example = "20250001")
+    private String studentNo;
+}

src/main/java/dmu/dasom/api/domain/interview/entity/InterviewReservation.java

@@ -36,4 +36,8 @@ public class InterviewReservation {
     @CreatedDate
     @Column(name = "created_at", nullable = false, updatable = false)
     private LocalDateTime createdAt; // 생성
+
+    public void setSlot(InterviewSlot slot) {
+        this.slot = slot;
+    }
 }

src/main/java/dmu/dasom/api/domain/interview/repository/InterviewReservationRepository.java

@@ -1,10 +1,15 @@
 package dmu.dasom.api.domain.interview.repository;
 
 import dmu.dasom.api.domain.interview.entity.InterviewReservation;
+import dmu.dasom.api.domain.applicant.entity.Applicant;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
 
+import java.util.Optional;
+
 @Repository
 public interface InterviewReservationRepository extends JpaRepository<InterviewReservation, Long> {
     boolean existsByReservationCode(String reservationCode);
+    Optional<InterviewReservation> findByReservationCode(String reservationCode);
+    Optional<InterviewReservation> findByApplicant(Applicant applicant);
 }

src/main/java/dmu/dasom/api/domain/interview/repository/InterviewSlotRepository.java

@@ -18,7 +18,7 @@ public interface InterviewSlotRepository extends JpaRepository<InterviewSlot, Lo
 
     // 상태에 따른 슬롯 조회
     @Query("SELECT s FROM InterviewSlot s WHERE s.interviewStatus = :status AND s.currentCandidates < s.maxCandidates")
-    List<InterviewSlot> findAllByStatusAndCurrentCandidatesLessThanMaxCandidates(InterviewStatus interviewStatus);
+        List<InterviewSlot> findAllByStatusAndCurrentCandidatesLessThanMaxCandidates(@org.springframework.data.repository.query.Param("status") InterviewStatus interviewStatus);
 
     // 슬롯이 하나라도 존재하는지 확인
     @Query("SELECT COUNT(s) > 0 FROM InterviewSlot s")

src/main/java/dmu/dasom/api/domain/interview/service/InterviewService.java

@@ -2,6 +2,7 @@
 
 import dmu.dasom.api.domain.interview.dto.InterviewReservationApplicantResponseDto;
 import dmu.dasom.api.domain.interview.dto.InterviewReservationRequestDto;
+import dmu.dasom.api.domain.interview.dto.InterviewReservationModifyRequestDto;
 import dmu.dasom.api.domain.interview.dto.InterviewSlotResponseDto;
 
 import java.time.LocalDate;
@@ -27,4 +28,7 @@ public interface InterviewService {
 
     List<InterviewReservationApplicantResponseDto> getAllInterviewApplicants();
 
+    // 면접 예약 수정
+    void modifyInterviewReservation(InterviewReservationModifyRequestDto request);
+
 }

src/main/java/dmu/dasom/api/domain/interview/service/InterviewServiceImpl.java

@@ -6,13 +6,15 @@
 import dmu.dasom.api.domain.common.exception.ErrorCode;
 import dmu.dasom.api.domain.interview.dto.InterviewReservationApplicantResponseDto;
 import dmu.dasom.api.domain.interview.dto.InterviewReservationRequestDto;
+import dmu.dasom.api.domain.interview.dto.InterviewReservationModifyRequestDto;
 import dmu.dasom.api.domain.interview.dto.InterviewSlotResponseDto;
 import dmu.dasom.api.domain.interview.entity.InterviewReservation;
 import dmu.dasom.api.domain.interview.entity.InterviewSlot;
 import dmu.dasom.api.domain.interview.enums.InterviewStatus;
 import dmu.dasom.api.domain.interview.repository.InterviewReservationRepository;
 import dmu.dasom.api.domain.interview.repository.InterviewSlotRepository;
 import dmu.dasom.api.domain.recruit.service.RecruitServiceImpl;
+import dmu.dasom.api.global.util.VerificationCodeManager;
 import jakarta.persistence.EntityListeners;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.jpa.domain.support.AuditingEntityListener;
@@ -35,6 +37,7 @@ public class InterviewServiceImpl implements InterviewService{
     private final InterviewReservationRepository interviewReservationRepository;
     private final ApplicantRepository applicantRepository;
     private final RecruitServiceImpl recruitService;
+    private final VerificationCodeManager verificationCodeManager;
 
     @Override
     @Transactional
@@ -148,7 +151,7 @@ public List<InterviewSlotResponseDto> getAllInterviewSlots() {
                 .toList();
     }
 
-    @Override
+        @Override
     public List<InterviewReservationApplicantResponseDto> getAllInterviewApplicants() {
         List<InterviewReservation> reservations = interviewReservationRepository.findAll();
 
@@ -172,4 +175,47 @@ public List<InterviewReservationApplicantResponseDto> getAllInterviewApplicants(
                 .collect(Collectors.toList());
     }
 
+    @Override
+    @Transactional
+    public void modifyInterviewReservation(InterviewReservationModifyRequestDto request) {
+        // 0. 인증 코드 검증
+        verificationCodeManager.verifyCode(request.getStudentNo(), request.getVerificationCode());
+
+        // 1. 지원자 학번과 이메일로 지원자 조회 및 검증
+        Applicant applicant = applicantRepository.findByStudentNoAndEmail(request.getStudentNo(), request.getEmail())
+                .orElseThrow(() -> new CustomException(ErrorCode.APPLICANT_NOT_FOUND));
+
+        // 2. 해당 지원자의 기존 면접 예약 조회
+        InterviewReservation existingReservation = interviewReservationRepository.findByApplicant(applicant)
+                .orElseThrow(() -> new CustomException(ErrorCode.RESERVATION_NOT_FOUND));
+
+        // 3. 새로운 면접 슬롯 조회 및 검증
+        InterviewSlot newSlot = interviewSlotRepository.findById(request.getNewSlotId())
+                .orElseThrow(() -> new CustomException(ErrorCode.SLOT_NOT_FOUND));
+
+        // 4. 새로운 슬롯이 현재 예약된 슬롯과 동일한지 확인 (불필요한 업데이트 방지)
+        if (existingReservation.getSlot().getId().equals(newSlot.getId())) {
+            return; // 동일한 슬롯으로 변경 요청 시 아무것도 하지 않음
+        }
+
+        // 5. 새로운 슬롯의 가용성 확인
+        if (newSlot.getCurrentCandidates() >= newSlot.getMaxCandidates() || newSlot.getInterviewStatus() != InterviewStatus.ACTIVE) {
+            throw new CustomException(ErrorCode.SLOT_UNAVAILABLE);
+        }
+
+        // 6. 기존 슬롯의 예약 인원 감소
+        InterviewSlot oldSlot = existingReservation.getSlot();
+        oldSlot.decrementCurrentCandidates();
+        interviewSlotRepository.save(oldSlot); // 변경된 oldSlot 저장
+
+        // 7. 예약 정보 업데이트 (새로운 슬롯으로 변경)
+        existingReservation.setSlot(newSlot);
+
+        // 8. 새로운 슬롯의 예약 인원 증가
+        newSlot.incrementCurrentCandidates();
+        interviewSlotRepository.save(newSlot); // 변경된 newSlot 저장
+
+        // 9. 업데이트된 예약 정보 저장
+        interviewReservationRepository.save(existingReservation);
+    }
 }

src/main/java/dmu/dasom/api/domain/recruit/controller/RecruitController.java

@@ -67,6 +67,20 @@ public ResponseEntity<List<RecruitConfigResponseDto>> getRecruitSchedule() {
         return ResponseEntity.ok(recruitService.getRecruitSchedule());
     }
 
+    @Operation(summary = "모집 일정 수정")
+    @PutMapping("/schedule")
+    public ResponseEntity<Void> modifyRecruitSchedule(@RequestBody dmu.dasom.api.domain.recruit.dto.RecruitScheduleModifyRequestDto request) {
+        recruitService.modifyRecruitSchedule(request);
+        return ResponseEntity.ok().build();
+    }
+
+    @Operation(summary = "TEMP: 모집 일정 초기화")
+    @GetMapping("/init-schedule")
+    public ResponseEntity<String> initSchedule() {
+        recruitService.initRecruitSchedule();
+        return ResponseEntity.ok("Recruit schedule initialized successfully.");
+    }
+
     // 합격 결과 확인
     @Operation(summary = "합격 결과 확인")
     @ApiResponses(value = {