✨ feat : 책 상세 정보 반환

src/main/java/com/hansung/leafly/domain/book/exception/BookErrorCode.java

@@ -0,0 +1,16 @@
+package com.hansung.leafly.domain.book.exception;
+
+import com.hansung.leafly.global.response.code.BaseResponseCode;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@AllArgsConstructor
+public enum BookErrorCode implements BaseResponseCode{
+    BOOK_NOT_FOUND("BOOK_404_1", 404, "해당 ISBN으로 검색된 책이 없습니다.");
+
+    private final String code;
+    private final int httpStatus;
+    private final String message;
+}

src/main/java/com/hansung/leafly/domain/book/exception/BookNotFoundException.java

@@ -0,0 +1,9 @@
+package com.hansung.leafly.domain.book.exception;
+
+import com.hansung.leafly.global.exception.BaseException;
+
+public class BookNotFoundException extends BaseException {
+    public BookNotFoundException() {
+        super(BookErrorCode.BOOK_NOT_FOUND);
+    }
+}

src/main/java/com/hansung/leafly/domain/book/service/BookService.java

@@ -1,10 +1,13 @@
 package com.hansung.leafly.domain.book.service;
 
 import com.hansung.leafly.domain.book.web.dto.BookFilterReq;
+import com.hansung.leafly.domain.book.web.dto.BookInfoRes;
 import com.hansung.leafly.domain.book.web.dto.SearchRes;
 
 import java.util.List;
 
 public interface BookService {
     List<SearchRes> search(String keyword, BookFilterReq req);
+
+    BookInfoRes details(Long isbn);
 }

src/main/java/com/hansung/leafly/domain/book/service/BookServiceImpl.java

@@ -1,25 +1,29 @@
 package com.hansung.leafly.domain.book.service;
 
 import com.hansung.leafly.domain.book.entity.enums.BookGenre;
+import com.hansung.leafly.domain.book.exception.BookNotFoundException;
 import com.hansung.leafly.domain.book.web.dto.*;
 import com.hansung.leafly.infra.aladin.AladinClient;
+import com.hansung.leafly.infra.aladin.dto.BookRes;
+import com.hansung.leafly.infra.openai.OpenAiClient;
+import com.hansung.leafly.infra.openai.dto.BookSummaryAiRes;
+import com.hansung.leafly.infra.openai.prompt.RecommendationPrompt;
 import lombok.RequiredArgsConstructor;
-import org.springframework.beans.factory.annotation.Value;
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
-import org.springframework.web.client.RestTemplate;
-import org.springframework.web.util.UriComponentsBuilder;
 
 import java.util.List;
 
 @Service
 @RequiredArgsConstructor
 public class BookServiceImpl implements BookService {
     private final AladinClient aladinClient;
+    private final OpenAiClient openAiClient;
 
     // 검색
     @Override
     public List<SearchRes> search(String keyword, BookFilterReq req) {
-        AladinSearchResponse response = aladinClient.search(keyword);
+        AladinSearchRes response = aladinClient.search(keyword);
 
         if (response == null || response.item() == null) {
             return List.of();
@@ -39,6 +43,39 @@ public List<SearchRes> search(String keyword, BookFilterReq req) {
                 .toList();
     }
 
+    @Override
+    public BookInfoRes details(Long isbn) {
+        // ISBN 기반 상세 정보 조회
+        BookRes bookRes = aladinClient.fetchBookByIsbn(String.valueOf(isbn));
+        if (bookRes == null ||
+                bookRes.getItems() == null ||
+                bookRes.getItems().isEmpty() ||
+                bookRes.getItems().get(0) == null) {
+            throw new BookNotFoundException();
+        }
+
+        BookDetailRes detail = BookDetailRes.from(bookRes);
+
+        // BookSummaryPrompt 생성 → AI 요약 + 태그 생성
+        String prompt = RecommendationPrompt.build(detail);
+        BookSummaryAiRes summaryAi = openAiClient.summarizeBook(prompt);
+
+        // 해당 카테고리 기반 추천 목록 검색
+        String categoryId = String.valueOf(bookRes.getItems().get(0).getCategoryId());
+        AladinSearchRes categorySearchRes = aladinClient.searchByCategory(categoryId);
+        List<RecommendRes> recommendations = toRecommendationList(categorySearchRes);
+
+        //boolean liked = likeService.isBookLiked(memberId, isbn13);
+
+        return BookInfoRes.of(
+                detail,
+                summaryAi.summary(),
+                summaryAi.tags(),
+                recommendations,
+                false
+        );
+    }
+
     //카테고리 필터링
     private boolean matchesGenre(AladinBookItem item, List<BookGenre> targetGenres) {
         String middle = extractMiddleCategory(item.categoryName());
@@ -57,4 +94,15 @@ private String extractMiddleCategory(String categoryName) {
         String[] tokens = categoryName.split(">");
         return tokens.length >= 2 ? tokens[1].trim() : "";
     }
+
+    private List<RecommendRes> toRecommendationList(AladinSearchRes res) {
+        return res.item().stream()
+                .map(item -> new RecommendRes(
+                        item.isbn13(),
+                        item.title(),
+                        item.author(),
+                        item.cover()
+                ))
+                .toList();
+    }
 }

src/main/java/com/hansung/leafly/domain/book/web/controller/BookController.java

@@ -2,6 +2,7 @@
 
 import com.hansung.leafly.domain.book.service.BookService;
 import com.hansung.leafly.domain.book.web.dto.BookFilterReq;
+import com.hansung.leafly.domain.book.web.dto.BookInfoRes;
 import com.hansung.leafly.domain.book.web.dto.SearchRes;
 import com.hansung.leafly.global.response.SuccessResponse;
 import jakarta.validation.Valid;
@@ -30,4 +31,13 @@ public ResponseEntity<SuccessResponse<List<SearchRes>>> search(
         List<SearchRes> res = bookService.search(keyword, req);
         return ResponseEntity.status(HttpStatus.OK).body(SuccessResponse.from(res));
     }
+
+    @GetMapping("/{isbn}")
+    public ResponseEntity<SuccessResponse<BookInfoRes>> details(
+        @PathVariable Long isbn
+    ){
+        BookInfoRes res = bookService.details(isbn);
+        return ResponseEntity.status(HttpStatus.OK).body(SuccessResponse.from(res));
+    }
+
 }

src/main/java/com/hansung/leafly/domain/book/web/dto/AladinSearchResponse.java → src/main/java/com/hansung/leafly/domain/book/web/dto/AladinSearchRes.java

@@ -2,7 +2,7 @@
 
 import java.util.List;
 
-public record AladinSearchResponse(
+public record AladinSearchRes(
         List<AladinBookItem> item
 ) {}
 

src/main/java/com/hansung/leafly/domain/book/web/dto/BookDetailRes.java

@@ -0,0 +1,31 @@
+package com.hansung.leafly.domain.book.web.dto;
+
+import com.hansung.leafly.infra.aladin.dto.BookRes;
+
+public record BookDetailRes(
+        String title,       //책 제목
+        String author,      //책 저자
+        String publisher,   //출판사
+        String pubDate,     //출판일
+        String description, //간략 소개
+        String isbn13,      //isbn값
+        String cover,       //책표지
+        int priceStandard,  //원가
+        int priceSales      //할인가
+) {
+    public static BookDetailRes from(BookRes res) {
+        BookRes.Item item = res.getItems().get(0);
+
+        return new BookDetailRes(
+                item.getTitle(),
+                item.getAuthor(),
+                item.getPublisher(),
+                item.getPubDate(),
+                item.getDescription(),
+                item.getIsbn13(),
+                item.getCover(),
+                item.getPriceStandard(),
+                item.getPriceSales()
+        );
+    }
+}

src/main/java/com/hansung/leafly/domain/book/web/dto/BookInfoRes.java

@@ -0,0 +1,26 @@
+package com.hansung.leafly.domain.book.web.dto;
+
+import java.util.List;
+
+public record BookInfoRes(
+        BookDetailRes bookDetail,     // 책 상세 정보
+        String aiSummary,             // AI가 생성한 요약 문장
+        List<String> aiTags,          // AI가 선정한 태그들
+        List<RecommendRes> recommendations, // 추천 책 리스트
+        boolean isLiked
+){
+    public static BookInfoRes of(
+        BookDetailRes bookDetailRes,
+        String aiSummary,
+        List<String> aiTags,
+        List<RecommendRes> recommendations,
+        boolean isLiked
+    ) {
+    return new BookInfoRes(
+            bookDetailRes,
+            aiSummary,
+            aiTags,
+            recommendations,
+            isLiked
+    );
+}}

src/main/java/com/hansung/leafly/domain/book/web/dto/RecommendRes.java

@@ -0,0 +1,8 @@
+package com.hansung.leafly.domain.book.web.dto;
+
+public record RecommendRes (
+        String isbn,
+        String title,
+        String author,
+        String cover
+) {}

src/main/java/com/hansung/leafly/domain/recommend/service/RecommendServiceImpl.java

@@ -1,6 +1,6 @@
 package com.hansung.leafly.domain.recommend.service;
 
-import com.hansung.leafly.domain.book.web.dto.AladinSearchResponse;
+import com.hansung.leafly.domain.book.web.dto.AladinSearchRes;
 import com.hansung.leafly.domain.book.web.dto.SearchRes;
 import com.hansung.leafly.domain.member.entity.Member;
 import com.hansung.leafly.domain.member.entity.Onboarding;
@@ -41,7 +41,7 @@ public List<RecommendRes> recommendations(Member member) {
 
         //실제 존재하는 책 필터링
         for (var book : aiRes.books()) {
-            AladinSearchResponse searchRes = aladinClient.search(book.title());
+            AladinSearchRes searchRes = aladinClient.search(book.title());
 
             if (searchRes == null || searchRes.item() == null || searchRes.item().isEmpty()) {
                 continue;

src/main/java/com/hansung/leafly/infra/aladin/AladinClient.java

@@ -1,7 +1,8 @@
 package com.hansung.leafly.infra.aladin;
 
-import com.hansung.leafly.domain.book.web.dto.AladinSearchResponse;
-import com.hansung.leafly.domain.book.web.dto.BookRes;
+import com.hansung.leafly.domain.book.web.dto.AladinSearchRes;
+import com.hansung.leafly.domain.book.web.dto.RecommendRes;
+import com.hansung.leafly.infra.aladin.dto.BookRes;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 import org.springframework.web.client.RestTemplate;
@@ -35,7 +36,7 @@ public BookRes fetchBookByIsbn(String isbn) {
         return restTemplate.getForObject(uri, BookRes.class);
     }
 
-    public AladinSearchResponse search(String keyword) {
+    public AladinSearchRes search(String keyword) {
         String uri = UriComponentsBuilder.fromHttpUrl(SEARCH_URL)
                 .queryParam("ttbkey", TTB_KEY)
                 .queryParam("Query", keyword)
@@ -47,7 +48,23 @@ public AladinSearchResponse search(String keyword) {
                 .build()
                 .toUriString();
 
-        return restTemplate.getForObject(uri, AladinSearchResponse.class);
+        return restTemplate.getForObject(uri, AladinSearchRes.class);
+    }
+
+    public AladinSearchRes searchByCategory(String categoryId) {
+        String uri = UriComponentsBuilder.fromHttpUrl(SEARCH_URL)
+                .queryParam("ttbkey", TTB_KEY)
+                .queryParam("Query", "*")   // 전체 검색
+                .queryParam("QueryType", "Keyword")
+                .queryParam("SearchTarget", "Book")
+                .queryParam("CategoryId", categoryId)
+                .queryParam("MaxResults", 6)
+                .queryParam("output", "js")
+                .queryParam("Version", "20131101")
+                .build()
+                .toUriString();
+
+        return restTemplate.getForObject(uri, AladinSearchRes.class);
     }
 }
 

src/main/java/com/hansung/leafly/infra/aladin/dto/BookRes.java

@@ -0,0 +1,40 @@
+package com.hansung.leafly.infra.aladin.dto;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+import java.util.List;
+
+@Getter
+@NoArgsConstructor
+@JsonIgnoreProperties(ignoreUnknown = true)
+public class BookRes {
+
+    @JsonProperty("item")
+    private List<Item> items;
+
+    public List<Item> getItems() {
+        return items;
+    }
+
+    @Getter
+    @NoArgsConstructor
+    @JsonIgnoreProperties(ignoreUnknown = true)
+    public static class Item {
+        private String title;
+        private String author;
+        private String pubDate;
+        private String publisher;
+        private String isbn;
+        private String isbn13;
+        private String description;
+        private String cover;
+        private Integer priceStandard;
+        private Integer priceSales;
+        private Double customerReviewRank;
+        private Integer categoryId;
+        private String categoryName;
+    }
+}