Merge pull request #707 from bounswe/fix/backend/related-questions

[Backend] Fix related questions

Author: mmtftr

backend/src/main/java/com/group1/programminglanguagesforum/Repositories/QuestionRepository.java

@@ -1,45 +1,47 @@
 package com.group1.programminglanguagesforum.Repositories;
 
-import com.group1.programminglanguagesforum.Entities.DifficultyLevel;
-import com.group1.programminglanguagesforum.Entities.Question;
-import com.group1.programminglanguagesforum.Entities.User;
+import java.util.List;
+import java.util.Optional;
+
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
-import java.util.List;
-import java.util.Optional;
+import com.group1.programminglanguagesforum.Entities.DifficultyLevel;
+import com.group1.programminglanguagesforum.Entities.Question;
+import com.group1.programminglanguagesforum.Entities.User;
 
 @Repository
 public interface QuestionRepository extends JpaRepository<Question, Long> {
+
     @Query("SELECT q FROM Question q JOIN q.tags t WHERE t.id = :tagId order by q.likeCount desc ")
     List<Question> findQuestionsByTagId(@Param("tagId") Long tagId);
 
-    @Query("SELECT DISTINCT q FROM Question q " +
-            "LEFT JOIN q.tags t " +
-            "WHERE (:query IS NULL OR " +
-            "      LOWER(q.title) LIKE LOWER(CONCAT('%', :query, '%')) OR " +
-            "      LOWER(q.questionBody) LIKE LOWER(CONCAT('%', :query, '%'))) " +
-            "AND (:tagIds IS NULL OR t.id IN :tagIds) " +
-            "AND (:difficulty IS NULL OR q.difficulty = :difficulty)")
+    @Query("SELECT DISTINCT q FROM Question q "
+            + "LEFT JOIN q.tags t "
+            + "WHERE (:query IS NULL OR "
+            + "      LOWER(q.title) LIKE LOWER(CONCAT('%', :query, '%')) OR "
+            + "      LOWER(q.questionBody) LIKE LOWER(CONCAT('%', :query, '%'))) "
+            + "AND (:tagIds IS NULL OR t.id IN :tagIds) "
+            + "AND (:difficulty IS NULL OR q.difficulty = :difficulty)")
     Page<Question> searchQuestions(
             @Param("query") String query,
             @Param("tagIds") List<Long> tagIds,
             @Param("difficulty") DifficultyLevel difficulty,
             Pageable pageable);
 
-    @Query("SELECT DISTINCT q FROM Question q " +
-           "LEFT JOIN q.tags t " +
-           "WHERE (:query IS NULL OR " +
-           "      LOWER(q.title) LIKE LOWER(CONCAT('%', :query, '%')) OR " +
-           "      LOWER(q.questionBody) LIKE LOWER(CONCAT('%', :query, '%'))) " +
-           "AND (:tagIds IS NULL OR t.id IN :tagIds) " +
-           "AND (:difficulty IS NULL OR q.difficulty = :difficulty) " +
-           "ORDER BY " +
-           "    CASE WHEN :authorIds IS NOT NULL AND q.askedBy.id IN :authorIds THEN 1 ELSE 0 END DESC")
+    @Query("SELECT DISTINCT q FROM Question q "
+            + "LEFT JOIN q.tags t "
+            + "WHERE (:query IS NULL OR "
+            + "      LOWER(q.title) LIKE LOWER(CONCAT('%', :query, '%')) OR "
+            + "      LOWER(q.questionBody) LIKE LOWER(CONCAT('%', :query, '%'))) "
+            + "AND (:tagIds IS NULL OR t.id IN :tagIds) "
+            + "AND (:difficulty IS NULL OR q.difficulty = :difficulty) "
+            + "ORDER BY "
+            + "    CASE WHEN :authorIds IS NOT NULL AND q.askedBy.id IN :authorIds THEN 1 ELSE 0 END DESC")
     Page<Question> searchQuestionsByRecommended(
             @Param("query") String query,
             @Param("authorIds") List<Long> authorIds,
@@ -52,5 +54,7 @@ Page<Question> searchQuestionsByRecommended(
 
     @Query("SELECT q.askedBy FROM Question q WHERE q.id = :id")
     Optional<User> findQuestionOwner(@Param("id") Long questionId);
-}
 
+    @Query("SELECT q FROM Question q JOIN q.tags t WHERE t.id = :tagId AND q.difficulty = :difficulty order by q.likeCount desc limit 3")
+    List<Question> findQuestionsByDifficultyAndTagId(@Param("difficulty") DifficultyLevel difficulty, @Param("tagId") Long tagId);
+}

backend/src/main/java/com/group1/programminglanguagesforum/Services/TagService.java

@@ -17,6 +17,7 @@
 import com.group1.programminglanguagesforum.DTOs.Responses.SelfProfileResponseDto;
 import com.group1.programminglanguagesforum.DTOs.Responses.TagDto;
 import com.group1.programminglanguagesforum.Entities.ComputerScienceTermTag;
+import com.group1.programminglanguagesforum.Entities.DifficultyLevel;
 import com.group1.programminglanguagesforum.Entities.ProgrammingLanguagesTag;
 import com.group1.programminglanguagesforum.Entities.ProgrammingParadigmTag;
 import com.group1.programminglanguagesforum.Entities.Question;
@@ -35,6 +36,7 @@
 @Service
 @RequiredArgsConstructor
 public class TagService {
+
     private final TagRepository tagRepository;
     private final ModelMapper modelMapper;
     private final QuestionRepository questionRepository;
@@ -85,7 +87,7 @@ public GetTagDetailsResponseDto getTagDetails(Long tagId) {
         }
         Tag tagEntity = tag.get();
         TagType tagType = getTagType(tagEntity);
-        List<Question> questions = questionRepository.findQuestionsByTagId(tagId);
+        List<Question> questions = questionRepository.findQuestionsByDifficultyAndTagId(DifficultyLevel.EASY, tagId);
         List<QuestionSummaryDto> relatedQuestions = questions.stream()
                 .map(QuestionService::mapToQuestionSummary)
                 .toList();
@@ -141,11 +143,11 @@ public GetTagDetailsResponseDto getTagDetails(Long tagId) {
     public List<SelfProfileResponseDto.FollowedTags> getFollowedTags(Long userId) {
         return tagRepository.findTagByFollowers(userId).stream()
                 .map(tag -> SelfProfileResponseDto.FollowedTags.builder()
-                        .id(tag.getId())
-                        .name(tag.getTagName())
-                        .tagType(getTagType(tag))
-                        .description(tag.getTagDescription())
-                        .build())
+                .id(tag.getId())
+                .name(tag.getTagName())
+                .tagType(getTagType(tag))
+                .description(tag.getTagDescription())
+                .build())
                 .toList();
     }
 

backend/src/test/java/com/group1/programminglanguagesforum/Services/TagServiceTests.java

@@ -142,6 +142,7 @@ void testGetTagDetails_Success() {
 
         when(tagRepository.findById(tagId)).thenReturn(Optional.of(mockTag));
         when(questionRepository.findQuestionsByTagId(tagId)).thenReturn(mockQuestions);
+        when(questionRepository.findQuestionsByDifficultyAndTagId(DifficultyLevel.EASY, tagId)).thenReturn(mockQuestions);
 
         // Mocking modelMapper behavior
         when(modelMapper.map(any(Question.class), eq(GetQuestionWithTagDto.class)))
@@ -161,7 +162,7 @@ void testGetTagDetails_Success() {
         assertEquals("Description1", response.getDescription());
         assertEquals(2, response.getRelatedQuestions().size());
         verify(tagRepository, times(1)).findById(tagId);
-        verify(questionRepository, times(1)).findQuestionsByTagId(tagId);
+        verify(questionRepository, times(1)).findQuestionsByDifficultyAndTagId(DifficultyLevel.EASY, tagId);
     }
 
     @Test