feat: 신규 사용자 abvDegree 점수 계산 로직 개선

Author: MEOHIN

src/main/java/com/back/domain/user/service/AbvScoreService.java

@@ -0,0 +1,77 @@
+package com.back.domain.user.service;
+
+import com.back.domain.user.entity.User;
+import com.back.domain.user.repository.UserRepository;
+import com.back.global.exception.ServiceException;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@RequiredArgsConstructor
+public class AbvScoreService {
+
+    private final UserRepository userRepository;
+
+    private static final double POST_SCORE = 0.5;
+    private static final double COMMENT_SCORE = 0.2;
+    private static final double LIKE_SCORE = 0.1;
+    private static final double KEEP_SCORE = 0.1;
+
+    @Transactional
+    public void awardForPost(Long userId) {
+        addScore(userId, POST_SCORE);
+    }
+
+    @Transactional
+    public void revokeForPost(Long userId) {
+        addScore(userId, -POST_SCORE);
+    }
+
+    @Transactional
+    public void awardForComment(Long userId) {
+        addScore(userId, COMMENT_SCORE);
+    }
+
+    @Transactional
+    public void revokeForComment(Long userId) {
+        addScore(userId, -COMMENT_SCORE);
+    }
+
+    @Transactional
+    public void awardForLike(Long userId) {
+        addScore(userId, LIKE_SCORE);
+    }
+
+    @Transactional
+    public void revokeForLike(Long userId) {
+        addScore(userId, -LIKE_SCORE);
+    }
+
+    @Transactional
+    public void awardForKeep(Long userId) {
+        addScore(userId, KEEP_SCORE);
+    }
+
+    @Transactional
+    public void revokeForKeep(Long userId) {
+        addScore(userId, -KEEP_SCORE);
+    }
+
+    private void addScore(Long userId, double delta) {
+        User user = userRepository.findById(userId)
+                .orElseThrow(() -> new ServiceException(404, "사용자를 찾을 수 없습니다."));
+
+        Double current = user.getAbvDegree();
+        if (current == null) current = 5.0; // 신규 사용자는 5%부터 시작
+
+        double next = clamp(current + delta, 0.0, 100.0);
+        user.setAbvDegree(next);
+
+        userRepository.save(user);
+    }
+
+    private static double clamp(double v, double min, double max) {
+        return Math.max(min, Math.min(max, v));
+    }
+}