Feature/#29 채팅 관련 로직 구현

src/main/java/sumcoda/boardbuddy/dto/ChatRoomResponse.java

@@ -0,0 +1,60 @@
+package sumcoda.boardbuddy.dto;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import sumcoda.boardbuddy.enumerate.MemberChatRoomRole;
+
+import java.time.LocalDateTime;
+
+public class ChatRoomResponse {
+
+    @Getter
+    @NoArgsConstructor
+    public static class InfoDTO {
+
+        private Long id;
+
+        private LocalDateTime joinedAt;
+
+        private MemberChatRoomRole memberChatRoomRole;
+
+        @Builder
+        public InfoDTO(Long id, LocalDateTime joinedAt, MemberChatRoomRole memberChatRoomRole) {
+            this.id = id;
+            this.joinedAt = joinedAt;
+            this.memberChatRoomRole = memberChatRoomRole;
+        }
+    }
+
+    @Getter
+    @NoArgsConstructor
+    public static class ValidateDTO {
+
+        private Long id;
+
+        @Builder
+        public ValidateDTO(Long id) {
+            this.id = id;
+        }
+    }
+
+    @Getter
+    @NoArgsConstructor
+    public static class ChatRoomDetailsDTO {
+
+        private Long chatRoomId;
+
+        private GatherArticleResponse.SimpleInfoDTO gatherArticleSimpleInfo;
+
+        private ChatMessageResponse.LastChatMessageInfoDTO lastChatMessageInfo;
+
+        @Builder
+        public ChatRoomDetailsDTO(Long chatRoomId, GatherArticleResponse.SimpleInfoDTO gatherArticleSimpleInfo, ChatMessageResponse.LastChatMessageInfoDTO lastChatMessageInfo) {
+            this.chatRoomId = chatRoomId;
+            this.gatherArticleSimpleInfo = gatherArticleSimpleInfo;
+            this.lastChatMessageInfo = lastChatMessageInfo;
+        }
+    }
+
+}

src/main/java/sumcoda/boardbuddy/repository/chatRoom/ChatRoomRepository.java

@@ -0,0 +1,14 @@
+package sumcoda.boardbuddy.repository.chatRoom;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import sumcoda.boardbuddy.entity.ChatRoom;
+
+import java.util.Optional;
+
+public interface ChatRoomRepository extends JpaRepository<ChatRoom, Long>, ChatRoomRepositoryCustom {
+    Optional<ChatRoom> findByGatherArticleId(Long gatherArticleId);
+
+    Optional<ChatRoom> findById(Long chatRoomId);
+
+    boolean existsById(Long chatRoomId);
+}

src/main/java/sumcoda/boardbuddy/repository/chatRoom/ChatRoomRepositoryCustom.java

@@ -0,0 +1,15 @@
+package sumcoda.boardbuddy.repository.chatRoom;
+
+import org.springframework.stereotype.Repository;
+import sumcoda.boardbuddy.dto.ChatRoomResponse;
+
+import java.util.List;
+import java.util.Optional;
+
+@Repository
+public interface ChatRoomRepositoryCustom {
+
+    Optional<ChatRoomResponse.ValidateDTO> findValidateDTOByGatherArticleId(Long gatherArticleId);
+
+    List<ChatRoomResponse.ChatRoomDetailsDTO> findChatRoomDetailsListByUsername(String username);
+}

src/main/java/sumcoda/boardbuddy/repository/chatRoom/ChatRoomRepositoryCustomImpl.java

@@ -0,0 +1,79 @@
+package sumcoda.boardbuddy.repository.chatRoom;
+
+import com.querydsl.core.types.Projections;
+import com.querydsl.jpa.JPAExpressions;
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import lombok.RequiredArgsConstructor;
+import sumcoda.boardbuddy.dto.ChatMessageResponse;
+import sumcoda.boardbuddy.dto.ChatRoomResponse;
+import sumcoda.boardbuddy.dto.GatherArticleResponse;
+
+import java.util.List;
+import java.util.Optional;
+
+import static sumcoda.boardbuddy.entity.QChatMessage.chatMessage;
+import static sumcoda.boardbuddy.entity.QChatRoom.*;
+import static sumcoda.boardbuddy.entity.QGatherArticle.gatherArticle;
+import static sumcoda.boardbuddy.entity.QMember.member;
+import static sumcoda.boardbuddy.entity.QMemberChatRoom.memberChatRoom;
+
+@RequiredArgsConstructor
+public class ChatRoomRepositoryCustomImpl implements ChatRoomRepositoryCustom {
+
+    private final JPAQueryFactory jpaQueryFactory;
+
+
+    /**
+     * 특정 모집글 Id로 ChatRoom 검증 정보 조회
+     *
+     * @param gatherArticleId 모집글 Id
+     * @return ChatRoom 검증 정보가 포함된 ValidateDTO 객체
+     **/
+    @Override
+    public Optional<ChatRoomResponse.ValidateDTO> findValidateDTOByGatherArticleId(Long gatherArticleId) {
+        return Optional.ofNullable(jpaQueryFactory.select(Projections.fields(ChatRoomResponse.ValidateDTO.class,
+                        chatRoom.id))
+                .from(chatRoom)
+                .join(chatRoom.gatherArticle, gatherArticle)
+                .where(gatherArticle.id.eq(gatherArticleId))
+                .fetchOne());
+    }
+
+    /**
+     * 특정 사용자 아이디 사용자가 속한 채팅방 상세 정보 목록 조회
+     *
+     * @param username 사용자 아이디
+     * @return 사용자가 속한 채팅방의 상세 정보 목록
+     **/
+    @Override
+    public List<ChatRoomResponse.ChatRoomDetailsDTO> findChatRoomDetailsListByUsername(String username) {
+        return jpaQueryFactory
+                .select(Projections.fields(ChatRoomResponse.ChatRoomDetailsDTO.class,
+                        chatRoom.id,
+                        Projections.constructor(GatherArticleResponse.SimpleInfoDTO.class,
+                                gatherArticle.id,
+                                gatherArticle.title,
+                                gatherArticle.meetingLocation,
+                                gatherArticle.currentParticipants
+                        ).as("gatherArticleSimpleInfo"),
+                        Projections.fields(ChatMessageResponse.LastChatMessageInfoDTO.class,
+                                chatMessage.content,
+                                chatMessage.createdAt.as("sentAt")
+                        )
+                ))
+                .from(chatRoom)
+                .leftJoin(chatRoom.chatMessages, chatMessage)
+                .join(chatRoom.gatherArticle, gatherArticle)
+                .join(chatRoom.memberChatRooms, memberChatRoom)
+                .join(memberChatRoom.member, member)
+                .where(member.username.eq(username)
+                        .and(chatMessage.createdAt.eq(
+                                JPAExpressions
+                                        .select(chatMessage.createdAt.max())
+                                        .from(chatMessage)
+                                        .where(chatMessage.chatRoom.id.eq(chatRoom.id))
+                        ))
+                )
+                .fetch();
+    }
+}