refactor: 인터뷰 기능 개선

backend/src/main/java/wooteco/prolog/interview/application/InterviewService.java

@@ -1,6 +1,7 @@
 package wooteco.prolog.interview.application;
 
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 import wooteco.prolog.common.exception.BadRequestException;
 import wooteco.prolog.interview.domain.InterviewSession;
 import wooteco.prolog.interview.domain.Interviewer;
@@ -33,6 +34,7 @@ public class InterviewService {
         this.interviewSessionMapper = interviewSessionMapper;
     }
 
+    @Transactional
     public InterviewSessionResponse createSession(
         final Long memberId,
         final InterviewSessionRequest request

backend/src/main/java/wooteco/prolog/interview/application/InterviewSessionMapper.java

@@ -24,7 +24,8 @@ public InterviewSessionResponse mapToResponse(final InterviewSession interviewSe
             interviewSession.getId(),
             interviewSession.getMemberId(),
             interviewSession.isFinished(),
-            mapToResponse(interviewSession.getMessages())
+            mapToResponse(interviewSession.getMessages()),
+            interviewSession.getRound()
         );
     }
 

backend/src/main/java/wooteco/prolog/interview/application/InterviewSessionResponse.java

@@ -1,12 +1,21 @@
 package wooteco.prolog.interview.application;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import java.util.List;
 
 public record InterviewSessionResponse(
     Long id,
     Long memberId,
     boolean finished,
-    List<InterviewMessageResponse> messages
+    List<InterviewMessageResponse> messages,
+    int currentRound
 ) {
+    private static final int START_ROUND = 1;
+    private static final int MAX_ROUND = 10;
 
+    @JsonProperty("remainRound")
+    public int remainRound() {
+        return MAX_ROUND + START_ROUND - currentRound;
+    }
 }

backend/src/main/java/wooteco/prolog/interview/domain/InterviewMessage.java

@@ -141,6 +141,10 @@ public boolean isIntervieweeFollowUp() {
         return sender == Sender.INTERVIEWEE && type == Type.FOLLOW_UP;
     }
 
+    public String getOriginalContent() {
+        return originalContent;
+    }
+
     @Override
     public String toString() {
         return "InterviewMessage{" +

backend/src/main/java/wooteco/prolog/interview/domain/InterviewMessages.java

@@ -16,6 +16,7 @@
 @Embeddable
 public class InterviewMessages {
 
+    private static final int START_ROUND = 1;
     private static final int MAX_ROUND = 10;
 
     @ElementCollection
@@ -39,7 +40,11 @@ public InterviewMessages with(final InterviewMessage message) {
         return new InterviewMessages(newValues);
     }
 
-    public int getRound() {
+    public int getCurrentRound() {
+        return getIntervieweeMessageCount() + START_ROUND;
+    }
+
+    public int getIntervieweeMessageCount() {
         return (int) values.stream()
             .filter(InterviewMessage::isByInterviewee)
             .count();
@@ -50,7 +55,12 @@ public List<InterviewMessage> values() {
     }
 
     public boolean canFinish() {
-        return getRound() >= MAX_ROUND && !hasInterviewerClosingSummary();
+        if (values.isEmpty()) {
+            return false;
+        }
+        return getCurrentRound() > MAX_ROUND &&
+            lastMessage().isByInterviewer() &&
+            !hasInterviewerClosingSummary();
     }
 
     private boolean hasInterviewerClosingSummary() {
@@ -76,6 +86,10 @@ public InterviewMessage lastMessage() {
         return values.getLast();
     }
 
+    List<InterviewMessage> getMessages() {
+        return Collections.unmodifiableList(values);
+    }
+
     @Override
     public String toString() {
         return "InterviewMessages{" +

backend/src/main/java/wooteco/prolog/interview/domain/InterviewSession.java

@@ -49,22 +49,23 @@ public void start(
     public void answer(
         final Interviewer interviewer,
         final Long memberId,
-        final String message
+        final String intervieweeAnswerContent
     ) {
         if (!this.memberId.equals(memberId)) {
             throw new BadRequestException(BadRequestCode.MEMBER_NOT_ALLOWED);
         }
-        if (finished) {
+        if (this.finished) {
             throw new BadRequestException(BadRequestCode.INTERVIEW_SESSION_FINISHED);
         }
-        if (interviewMessages.lastMessage().isByInterviewee()) {
+        if (interviewMessages.isEmpty() || interviewMessages.lastMessage().isByInterviewee()) {
             throw new BadRequestException(BadRequestCode.INTERVIEW_SESSION_NOT_YOUR_TURN);
         }
 
-        interviewMessages = interviewer.followUp(interviewMessages, message);
-        if (interviewMessages.canFinish()) {
-            finished = true;
-            interviewMessages = interviewer.finish(interviewMessages);
+        this.interviewMessages = interviewer.followUp(this.interviewMessages, intervieweeAnswerContent);
+
+        if (this.interviewMessages.canFinish()) {
+            this.finished = true;
+            this.interviewMessages = interviewer.finish(this.interviewMessages);
         }
     }
 
@@ -83,4 +84,8 @@ public boolean isFinished() {
     public InterviewMessages getMessages() {
         return interviewMessages;
     }
+
+    public int getRound() {
+        return interviewMessages.getCurrentRound();
+    }
 }

backend/src/main/java/wooteco/prolog/interview/infrastructure/AzureOpenAiInterviewer.java

@@ -120,20 +120,19 @@ public InterviewMessages followUp(
         final InterviewMessages interviewMessages,
         final String answer
     ) {
-        if (interviewMessages.getRound() > totalQuestionCount) {
+        if (interviewMessages.getCurrentRound() > totalQuestionCount) {
             throw new IllegalStateException("인터뷰가 종료되었습니다.");
         }
 
         log.debug("Follow up [interviewMessages={}, answer={}]", interviewMessages, answer);
-        final var messages = interviewMessages.with(createUserMessage(interviewMessages.getRound(), answer));
-        if (messages.canFinish()) {
-            return messages;
-        }
 
-        final var rawFollowUpQuestion = askToInterviewer(messages);
-        checkFollowUpQuestion(rawFollowUpQuestion);
+        final var messagesWithUserAnswer = interviewMessages.with(createUserMessage(interviewMessages.getCurrentRound(), answer));
+
+        final var rawFollowUpQuestion = askToInterviewer(messagesWithUserAnswer);
+        checkFollowUpQuestion(rawFollowUpQuestion); // Validates AI response format
 
-        return messages.with(InterviewMessage.ofInterviewer(rawFollowUpQuestion));
+        // Add AI's new message (the follow-up question/statement) to the history.
+        return messagesWithUserAnswer.with(InterviewMessage.ofInterviewer(rawFollowUpQuestion));
     }
 
     private void checkFollowUpQuestion(final String rawFollowUpQuestion) {
@@ -165,7 +164,7 @@ private InterviewMessage createUserMessage(
 
     @Override
     public InterviewMessages finish(final InterviewMessages interviewMessages) {
-        if (interviewMessages.getRound() <= totalQuestionCount) {
+        if (interviewMessages.getCurrentRound() < totalQuestionCount) {
             throw new IllegalStateException("인터뷰가 종료되지 않았습니다.");
         }
 

backend/src/main/resources/prompts/qna-interview-interactive-follow-up.st

@@ -1,5 +1,8 @@
 당신은 인터뷰어입니다. 인터뷰이의 답변을 기반으로 추가 질문을 생성해야 합니다.
 
+다만, 인터뷰의 진행은 **초기 학습 목표와 첫 질문의 주제 흐름을 유지하는 것**을 가장 우선시합니다.
+인터뷰이의 답변이 이 흐름을 벗어나는 경우, 이를 부드럽게 다시 본래의 맥락으로 유도하는 질문을 제시해야 합니다.
+
 다음 형식으로 응답을 작성하세요.
 
 ---
@@ -13,6 +16,7 @@
 
 ## 🔄 **추가 질문 (Follow-up Question)**
 👉 인터뷰이의 답변을 기반으로, 사고를 확장할 수 있도록 추가 질문을 1개 제시하세요.
+❗단, 인터뷰 주제 또는 초기 질문 흐름을 벗어난 경우, 원래 학습 목표를 다시 강조하거나 관련 개념으로 되돌리는 질문을 우선적으로 제시해야 합니다.
 
 예시:
 - "이 개념을 실전에서 적용한 경험이 있나요? 어떤 사례였나요?"
@@ -29,14 +33,14 @@
 크루의 응답을 평가한 결과는 JSON 형식으로 제공됩니다.
 추가적인 설명 없이, **순수한 JSON 데이터만 반환**하세요.
 
-### **❗ 필수 규칙**
+### ❗ **필수 규칙**
 - 인터뷰이의 답변이 부족하더라도 **무조건 JSON 형식으로 피드백을 제공**해야 합니다.
 - **반드시 순수한 JSON 데이터만 출력**하고, 코드 블록을 포함하지 마세요.
 - 추가적인 설명이나 문장은 출력하지 말고, JSON 데이터만 반환하세요.
 - 추가 질문은 한글로 작성합니다.
 
-### **❗ 응답 형식**
+### ❗ **응답 형식**
 {responseFormat}
 
-### **❗ 응답 예시**
+### ❗ **응답 예시**
 {responseExample}

backend/src/test/java/wooteco/prolog/interview/domain/InterviewMessagesTest.java

@@ -5,27 +5,28 @@
 import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertAll;
 
 class InterviewMessagesTest {
 
     @Test
-    void 인터뷰이의_답변_갯수가_라운드다() {
+    void 인터뷰이의_답변_갯수를_조회한다() {
         InterviewMessages interviewMessages = new InterviewMessages(List.of(
             InterviewMessage.ofInterviewee("질문2", "질문2")
         ));
 
-        assertThat(interviewMessages.getRound()).isEqualTo(1);
+        assertThat(interviewMessages.getIntervieweeMessageCount()).isEqualTo(1);
     }
 
     @Test
-    void 인터뷰이의_답변이_3개면_3라운드다() {
+    void 인터뷰이의_답변이_3개다() {
         InterviewMessages interviewMessages = new InterviewMessages(List.of(
             InterviewMessage.ofInterviewee("질문1", "질문1"),
             InterviewMessage.ofInterviewee("질문2", "질문2"),
             InterviewMessage.ofInterviewee("질문3", "질문3")
         ));
 
-        assertThat(interviewMessages.getRound()).isEqualTo(3);
+        assertThat(interviewMessages.getIntervieweeMessageCount()).isEqualTo(3);
     }
 
     @Test
@@ -41,7 +42,62 @@ class InterviewMessagesTest {
             assertThat(interviewMessages.canFinish()).isFalse();
         }
 
-        interviewMessages = interviewMessages.with(InterviewMessage.ofInterviewee("답변입니다", "답변입니다"));
+        interviewMessages = interviewMessages.with(InterviewMessage.ofInterviewee("답변입니다", "답변입니다"))
+            .with(InterviewMessage.ofInterviewer("질문입니다"));
         assertThat(interviewMessages.canFinish()).isTrue();
     }
+
+
+    @Test
+    void 빈_메시지_리스트로_생성시_인터뷰이_답변수는_0이고_종료할수_없다() {
+        InterviewMessages interviewMessages = new InterviewMessages(List.of());
+
+        assertAll(
+            () -> assertThat(interviewMessages.getMessages()).isEmpty(),
+            () -> assertThat(interviewMessages.getIntervieweeMessageCount()).isZero(),
+            () -> assertThat(interviewMessages.canFinish()).isFalse()
+        );
+    }
+
+    @Test
+    void 종료조건_인터뷰이_답변_부족시_종료불가() {
+        InterviewMessages interviewMessages = new InterviewMessages(List.of(
+            InterviewMessage.ofSystemGuide("시스템 가이드라인")
+        ));
+        for (int i = 0; i < 9; i++) { // 9개의 질문-답변 쌍
+            interviewMessages = interviewMessages.with(InterviewMessage.ofInterviewer("질문 " + (i + 1)))
+                .with(InterviewMessage.ofInterviewee("답변 " + (i + 1), "답변 " + (i + 1)));
+            assertThat(interviewMessages.canFinish()).isFalse();
+        }
+        // 마지막 인터뷰어 질문만 추가 (총 9개의 답변, 10개의 질문)
+        interviewMessages = interviewMessages.with(InterviewMessage.ofInterviewer("질문 10"));
+        assertThat(interviewMessages.canFinish()).isFalse();
+        assertThat(interviewMessages.getIntervieweeMessageCount()).isEqualTo(9);
+    }
+
+    @Test
+    void 인터뷰이_답변_개수_정확히_계산_확인() {
+        InterviewMessages interviewMessages = new InterviewMessages(List.of(
+            InterviewMessage.ofSystemGuide("가이드1"),
+            InterviewMessage.ofInterviewer("질문1"),
+            InterviewMessage.ofInterviewee("답변1", "답변1"), // 1
+            InterviewMessage.ofSystemGuide("가이드2"),
+            InterviewMessage.ofInterviewer("질문2"),
+            InterviewMessage.ofInterviewee("답변2", "답변2"), // 2
+            InterviewMessage.ofInterviewer("질문3"),
+            InterviewMessage.ofInterviewee("답변3", "답변3")  // 3
+        ));
+        assertThat(interviewMessages.getIntervieweeMessageCount()).isEqualTo(3);
+    }
+
+    @Test
+    void 인터뷰이_메시지_없을때_답변수_0_반환() {
+        InterviewMessages interviewMessages = new InterviewMessages(List.of(
+            InterviewMessage.ofSystemGuide("가이드1"),
+            InterviewMessage.ofInterviewer("질문1"),
+            InterviewMessage.ofSystemGuide("가이드2"),
+            InterviewMessage.ofInterviewer("질문2")
+        ));
+        assertThat(interviewMessages.getIntervieweeMessageCount()).isZero();
+    }
 }

frontend/src/pages/InterviewPage/InterviewPage.tsx

@@ -1,8 +1,8 @@
 /** @jsxImportSource @emotion/react */
 
-import React, { useState } from 'react';
+import React, {useState} from 'react';
 import styled from '@emotion/styled';
-import { MainContentStyle } from '../../PageRouter';
+import {MainContentStyle} from '../../PageRouter';
 import InterviewSetup from './InterviewSetup';
 import InterviewSession from './InterviewSession';
 
@@ -53,20 +53,41 @@ const SectionTitle = styled.h2`
   margin: 0;
 `;
 
+const RoundInfo = styled.span`
+  font-size: 1rem;
+  font-weight: 400;
+  color: #666;
+  margin-left: 1rem;
+`;
+
 const SectionContent = styled.div`
   flex: 1;
   min-height: 0;
   padding: 2rem;
 `;
 
+interface InterviewSessionData {
+  id: number;
+  memberId: number;
+  finished: boolean;
+  messages: {
+    sender: 'SYSTEM' | 'INTERVIEWER' | 'INTERVIEWEE';
+    content: string;
+    hint: string;
+    createdAt: string;
+  }[];
+  currentRound: number;
+  remainRound: number;
+}
+
 const InterviewPage = () => {
-  const [session, setSession] = useState<any>(null);
+  const [session, setSession] = useState<InterviewSessionData | null>(null);
 
-  const handleSessionStart = (newSession: any) => {
+  const handleSessionStart = (newSession: InterviewSessionData) => {
     setSession(newSession);
   };
 
-  const handleSessionUpdate = (updatedSession: any) => {
+  const handleSessionUpdate = (updatedSession: InterviewSessionData) => {
     setSession(updatedSession);
   };
 
@@ -91,7 +112,14 @@ const InterviewPage = () => {
           </SetupSection>
           <SessionSection>
             <SectionHeader>
-              <SectionTitle>레벨 인터뷰 진행</SectionTitle>
+              <SectionTitle>
+                레벨 인터뷰 진행
+                {session &&
+                    <RoundInfo>
+                        남은 인터뷰: {session.remainRound}회
+                    </RoundInfo>
+                }
+              </SectionTitle>
             </SectionHeader>
             <SectionContent>
               <InterviewSession