Add unit tests for exam scoring service

src/main/java/com/example/questionbank/repository/ExamAttemptRepository.java

@@ -2,6 +2,7 @@ package com.example.questionbank.repository;
 
 import com.example.questionbank.domain.ExamAttempt;
 import java.util.List;
+import java.util.List;
 import java.util.Optional;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
@@ -14,6 +15,8 @@ import org.springframework.stereotype.Repository;
  */
 @Repository
 public interface ExamAttemptRepository extends JpaRepository<ExamAttempt, Long> {
+    List<ExamAttempt> findAllByUserLogin(String login);
+
     @Query("select examAttempt from ExamAttempt examAttempt where examAttempt.user.login = ?#{authentication.name}")
     List<ExamAttempt> findByUserIsCurrentUser();
 

src/main/java/com/example/questionbank/repository/QuestionRepository.java

@@ -2,6 +2,7 @@ package com.example.questionbank.repository;
 
 import com.example.questionbank.domain.Question;
 import java.util.List;
+import java.util.List;
 import java.util.Optional;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
@@ -14,6 +15,8 @@ import org.springframework.stereotype.Repository;
  */
 @Repository
 public interface QuestionRepository extends JpaRepository<Question, Long> {
+    List<Question> findAllBySubjectIdAndActiveTrue(Long subjectId);
+
     default Optional<Question> findOneWithEagerRelationships(Long id) {
         return this.findOneWithToOneRelationships(id);
     }

src/main/java/com/example/questionbank/service/quiz/ExamScoringService.java

@@ -0,0 +1,15 @@
+package com.example.questionbank.service.quiz;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+import org.springframework.stereotype.Service;
+
+@Service
+public class ExamScoringService {
+
+    public ScoringResult score(OptionKey correctOption, OptionKey selectedOption) {
+        boolean correct = selectedOption != null && selectedOption == correctOption;
+        return new ScoringResult(correct, correct ? 1 : 0);
+    }
+
+    public record ScoringResult(boolean correct, int awardedPoints) {}
+}

src/main/java/com/example/questionbank/web/rest/dto/AnswerResult.java

@@ -0,0 +1,13 @@
+package com.example.questionbank.web.rest.dto;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+
+public record AnswerResult(
+    Long questionId,
+    String questionText,
+    OptionKey selectedOption,
+    String selectedContent,
+    boolean correct,
+    int awardedPoints,
+    String explanation
+) {}

src/main/java/com/example/questionbank/web/rest/dto/ChoiceView.java

@@ -0,0 +1,5 @@
+package com.example.questionbank.web.rest.dto;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+
+public record ChoiceView(OptionKey optionKey, String content, Integer displayOrder) {}

src/main/java/com/example/questionbank/web/rest/dto/ExamAttemptStartResult.java

@@ -0,0 +1,5 @@
+package com.example.questionbank.web.rest.dto;
+
+import java.time.Instant;
+
+public record ExamAttemptStartResult(Long attemptId, Instant startedAt) {}

src/main/java/com/example/questionbank/web/rest/dto/ExamAttemptSummary.java

@@ -0,0 +1,14 @@
+package com.example.questionbank.web.rest.dto;
+
+import com.example.questionbank.domain.enumeration.AttemptStatus;
+import java.time.Instant;
+
+public record ExamAttemptSummary(
+    Long attemptId,
+    Long subjectId,
+    String subjectName,
+    Instant startedAt,
+    Instant submittedAt,
+    AttemptStatus status,
+    Integer score
+) {}

src/main/java/com/example/questionbank/web/rest/dto/ExamQuestionView.java

@@ -0,0 +1,5 @@
+package com.example.questionbank.web.rest.dto;
+
+import java.util.List;
+
+public record ExamQuestionView(Long questionId, String prompt, List<ChoiceView> choices) {}

src/main/java/com/example/questionbank/web/rest/dto/ExamResult.java

@@ -0,0 +1,6 @@
+package com.example.questionbank.web.rest.dto;
+
+import java.time.Instant;
+import java.util.List;
+
+public record ExamResult(Long attemptId, int totalScore, Instant submittedAt, List<AnswerResult> answers) {}

src/main/java/com/example/questionbank/web/rest/dto/StartExamRequest.java

@@ -0,0 +1,5 @@
+package com.example.questionbank.web.rest.dto;
+
+import jakarta.validation.constraints.NotNull;
+
+public record StartExamRequest(@NotNull Long subjectId) {}

src/main/java/com/example/questionbank/web/rest/dto/SubmitAnswerRequest.java

@@ -0,0 +1,6 @@
+package com.example.questionbank.web.rest.dto;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+import jakarta.validation.constraints.NotNull;
+
+public record SubmitAnswerRequest(@NotNull Long questionId, OptionKey selectedOption) {}

src/main/java/com/example/questionbank/web/rest/dto/SubmitExamRequest.java

@@ -0,0 +1,7 @@
+package com.example.questionbank.web.rest.dto;
+
+import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotEmpty;
+import java.util.List;
+
+public record SubmitExamRequest(@NotEmpty List<@Valid SubmitAnswerRequest> answers) {}

src/test/java/com/example/questionbank/service/quiz/ExamScoringServiceTest.java

@@ -0,0 +1,37 @@
+package com.example.questionbank.service.quiz;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import com.example.questionbank.domain.enumeration.OptionKey;
+import org.junit.jupiter.api.Test;
+
+class ExamScoringServiceTest {
+
+    private final ExamScoringService service = new ExamScoringService();
+
+    @Test
+    void correctAnswerGetsOnePoint() {
+        var result = service.score(OptionKey.A, OptionKey.A);
+
+        assertTrue(result.correct());
+        assertEquals(1, result.awardedPoints());
+    }
+
+    @Test
+    void wrongAnswerGetsZeroPoints() {
+        var result = service.score(OptionKey.A, OptionKey.D);
+
+        assertFalse(result.correct());
+        assertEquals(0, result.awardedPoints());
+    }
+
+    @Test
+    void unansweredQuestionGetsZeroPoints() {
+        var result = service.score(OptionKey.A, null);
+
+        assertFalse(result.correct());
+        assertEquals(0, result.awardedPoints());
+    }
+}