feat: QuestionsScoreCalculator 구현

backend/bang-ggood/src/main/java/com/bang_ggood/question/domain/QuestionsScoreCalculator.java

@@ -0,0 +1,29 @@
+package com.bang_ggood.question.domain;
+
+import java.util.List;
+
+public class QuestionsScoreCalculator {
+
+    private static final int NO_QUESTIONS_ANSWERED = 0;
+    private static final int PERCENT = 100;
+
+    private final ChecklistQuestions allAnsweredQuestions;
+    private final ChecklistQuestions goodAnsweredQuestions;
+
+    public QuestionsScoreCalculator(List<ChecklistQuestion> questions) {
+        this.allAnsweredQuestions = new ChecklistQuestions(questions);
+        this.goodAnsweredQuestions = new ChecklistQuestions(allAnsweredQuestions.filterByAnswer(Answer.GOOD));
+    }
+
+    public Integer calculateScore() {
+        int allAnsweredQuestionCount = allAnsweredQuestions.size();
+        int goodAnsweredQuestionCount = goodAnsweredQuestions.size();
+
+        if (allAnsweredQuestionCount == NO_QUESTIONS_ANSWERED) {
+            return null;
+        }
+
+        double score = ((double) goodAnsweredQuestionCount / allAnsweredQuestionCount) * PERCENT;
+        return (int) Math.round(score);
+    }
+}

backend/bang-ggood/src/test/java/com/bang_ggood/question/domain/QuestionsScoreCalculatorTest.java

@@ -0,0 +1,103 @@
+package com.bang_ggood.question.domain;
+
+import com.bang_ggood.IntegrationTestSupport;
+import com.bang_ggood.checklist.ChecklistFixture;
+import com.bang_ggood.checklist.domain.Checklist;
+import com.bang_ggood.checklist.repository.ChecklistRepository;
+import com.bang_ggood.question.ChecklistQuestionFixture;
+import com.bang_ggood.question.QuestionFixture;
+import com.bang_ggood.room.RoomFixture;
+import com.bang_ggood.room.domain.Room;
+import com.bang_ggood.room.repository.RoomRepository;
+import com.bang_ggood.user.UserFixture;
+import com.bang_ggood.user.domain.User;
+import com.bang_ggood.user.repository.UserRepository;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class QuestionsScoreCalculatorTest extends IntegrationTestSupport {
+
+    @Autowired
+    private ChecklistRepository checklistRepository;
+
+    @Autowired
+    private RoomRepository roomRepository;
+
+    @Autowired
+    private UserRepository userRepository;
+
+    private Checklist checklist;
+
+    @BeforeEach
+    void beforeEach() {
+        User user = userRepository.save(UserFixture.USER1());
+        Room room = roomRepository.save(RoomFixture.ROOM_1());
+        checklist = checklistRepository.save(ChecklistFixture.CHECKLIST1_USER1(room, user));
+    }
+
+    @DisplayName("점수 계산 성공 : 모두 GOOD일 경우")
+    @Test
+    void calculateCategoryScore() {
+        // given
+        List<ChecklistQuestion> checklistQuestions = List.of(
+                ChecklistQuestionFixture.CHECKLIST1_QUESTION2_GOOD(checklist, QuestionFixture.QUESTION1_CATEGORY1)
+        );
+
+        // when
+        QuestionsScoreCalculator calculator = new QuestionsScoreCalculator(checklistQuestions);
+
+        // then
+        assertThat(calculator.calculateScore()).isEqualTo(100);
+    }
+
+    @DisplayName("점수 계산 성공 : 일부 답변만 GOOD인 경우")
+    @Test
+    void calculateCategoryScore_partialGoodAnswers() {
+        // given
+        List<ChecklistQuestion> checklistQuestions = List.of(
+                ChecklistQuestionFixture.CHECKLIST1_QUESTION1_BAD(checklist, QuestionFixture.QUESTION1_CATEGORY1),
+                ChecklistQuestionFixture.CHECKLIST1_QUESTION2_GOOD(checklist, QuestionFixture.QUESTION2_CATEGORY1)
+        );
+
+        // when
+        QuestionsScoreCalculator calculator = new QuestionsScoreCalculator(checklistQuestions);
+
+        // then
+        assertThat(calculator.calculateScore()).isEqualTo(50);
+    }
+
+    @DisplayName("점수 계산 성공 : 모든 답변이 BAD인 경우")
+    @Test
+    void calculateCategoryScore_allBadAnswers() {
+        // given
+        List<ChecklistQuestion> checklistQuestions = List.of(
+                ChecklistQuestionFixture.CHECKLIST1_QUESTION1_BAD(checklist, QuestionFixture.QUESTION1_CATEGORY1)
+        );
+
+        // when
+        QuestionsScoreCalculator calculator = new QuestionsScoreCalculator(checklistQuestions);
+
+        // then
+        assertThat(calculator.calculateScore()).isEqualTo(0);
+    }
+
+    @DisplayName("점수 계산 성공 : 답변이 없는 경우")
+    @Test
+    void calculateCategoryScore_noAnswers() {
+        // given & when
+        List<ChecklistQuestion> checklistQuestions = new ArrayList<>();
+
+        // when
+        QuestionsScoreCalculator calculator = new QuestionsScoreCalculator(checklistQuestions);
+
+        // then
+        assertThat(calculator.calculateScore()).isEqualTo(null);
+    }
+
+}