feat: #119-헬퍼 매칭글 리스트 필터 및 페이지네이션 Repository 구현

back/src/main/java/com/example/capstone/domain/help/repository/HelpRepositoryImpl.java

@@ -0,0 +1,75 @@
+package com.example.capstone.domain.help.repository;
+
+import com.example.capstone.domain.help.dto.HelpListResponse;
+import com.example.capstone.domain.help.dto.HelpSliceResponse;
+import com.example.capstone.domain.help.entity.QHelp;
+import com.querydsl.core.types.Projections;
+import com.querydsl.core.types.dsl.BooleanExpression;
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import lombok.RequiredArgsConstructor;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Slice;
+import org.springframework.data.domain.SliceImpl;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+@RequiredArgsConstructor
+public class HelpRepositoryImpl implements HelpListRepository {
+
+    private final JPAQueryFactory jpaQueryFactory;
+    private QHelp help = QHelp.help;
+
+    @Override
+    public HelpSliceResponse getHelpListByPaging(Long cursorId, Pageable page, Boolean isDone, Boolean isHelper, UUID isMine) {
+        List<HelpListResponse> helpList = jpaQueryFactory
+                .select(
+                        Projections.constructor(
+                                HelpListResponse.class,
+                                help.id, help.title,
+                                help.author, help.country,
+                                help.createdDate, help.isDone, help.isHelper
+                        )
+                )
+                .from(help)
+                .where(cursorId(cursorId),
+                        doneEq(isDone),
+                        helperEq(isHelper),
+                        mineEq(isMine))
+                .orderBy(help.createdDate.desc())
+                .limit(page.getPageSize() + 1)
+                .fetch();
+
+        boolean hasNext = false;
+        if(helpList.size() > page.getPageSize()) {
+            helpList.remove(page.getPageSize());
+            hasNext = true;
+        }
+
+        Long lastCursorId = null;
+
+        if(hasNext && helpList.size() != 0) {
+            lastCursorId = helpList.get(helpList.size() - 1).id();
+        }
+
+        return new HelpSliceResponse(lastCursorId, hasNext, helpList);
+    }
+
+    private BooleanExpression cursorId(Long cursorId) {
+        return cursorId == null ? null : help.id.gt(cursorId);
+    }
+
+    private  BooleanExpression doneEq(Boolean isDone) {
+        return isDone == null ? null : help.isDone.eq(isDone);
+    }
+
+    private  BooleanExpression helperEq(Boolean isHelper) {
+        return isHelper == null ? null : help.isHelper.eq(isHelper);
+    }
+
+    private  BooleanExpression mineEq(UUID isMine) {
+        return isMine == null ? null : help.uuid.eq(isMine);
+    }
+}