Refractor reviews

src/main/java/ru/yandex/practicum/filmorate/controller/ReviewController.java

@@ -10,6 +10,7 @@
 import ru.yandex.practicum.filmorate.dto.review.NewReviewRequest;
 import ru.yandex.practicum.filmorate.dto.review.ReviewDto;
 import ru.yandex.practicum.filmorate.dto.review.UpdateReviewRequest;
+import ru.yandex.practicum.filmorate.model.Reaction;
 import ru.yandex.practicum.filmorate.service.review.ReviewService;
 
 import java.util.Collection;
@@ -72,13 +73,13 @@ public void setDislike(@PathVariable @Positive long id,
     public void removeLike(@PathVariable @Positive long id,
                            @PathVariable @Positive long userId) {
         log.trace("Remove review like by reviewId: {}, from userId: {}", id, userId);
-        reviewService.removeLike(id, userId);
+        reviewService.removeReaction(id, userId, Reaction.LIKE);
     }
 
     @DeleteMapping("/{id}/dislike/{userId}")
     public void removeDislike(@PathVariable @Positive long id,
                               @PathVariable @Positive long userId) {
         log.trace("Remove review dislike by reviewId: {}, from userId: {}", id, userId);
-        reviewService.removeDislike(id, userId);
+        reviewService.removeReaction(id, userId, Reaction.DISLIKE);
     }
-}
+}

src/main/java/ru/yandex/practicum/filmorate/model/Reaction.java

@@ -0,0 +1,5 @@
+package ru.yandex.practicum.filmorate.model;
+
+public enum Reaction {
+    LIKE, DISLIKE
+}

src/main/java/ru/yandex/practicum/filmorate/repository/review/JdbcReviewRepository.java

@@ -6,6 +6,7 @@
 import org.springframework.jdbc.core.namedparam.NamedParameterJdbcOperations;
 import org.springframework.jdbc.support.GeneratedKeyHolder;
 import org.springframework.stereotype.Repository;
+import ru.yandex.practicum.filmorate.model.Reaction;
 import ru.yandex.practicum.filmorate.model.Review;
 
 import java.util.Collection;
@@ -25,10 +26,6 @@ public class JdbcReviewRepository implements ReviewRepository {
             FROM reviews r
             JOIN film_reviews fr ON r.review_id = fr.review_id
             """;
-    private static final int UP_UR = 1;
-    private static final int DOUBLE_UP_UR = 2;
-    private static final int DROP_UR = -1;
-    private static final int DOUBLE_DROP_UR = -2;
     private final NamedParameterJdbcOperations jdbc;
     private final RowMapper<Review> mapper;
 
@@ -95,59 +92,30 @@ public Collection<Review> findAllByFilm(Long filmId, long count) {
     }
 
     @Override
-    public void setLike(long id, long userId) {
+    public void setReaction(long id, long userId, Reaction reaction) {
         MapSqlParameterSource params = new MapSqlParameterSource("review_id", id)
                 .addValue("user_id", userId);
-        Boolean isPositiveYet = isPositive(params);
-        jdbc.update("""
-                MERGE INTO review_likes (review_id, user_id, is_positive)
-                KEY (review_id, user_id)
-                VALUES (:review_id, :user_id, TRUE)
-                """, params);
-        if (isPositiveYet == null) {
-            changeUsefulRating(params, UP_UR);
-        } else if (isPositiveYet) {
-            changeUsefulRating(params, DOUBLE_UP_UR);
+        switch (reaction) {
+            case LIKE -> params.addValue("is_positive", true);
+            case DISLIKE -> params.addValue("is_positive", false);
         }
-    }
-
-    @Override
-    public void setDislike(long id, long userId) {
-        MapSqlParameterSource params = new MapSqlParameterSource("review_id", id)
-                .addValue("user_id", userId);
-        Boolean isPositiveYet = isPositive(params);
         jdbc.update("""
                 MERGE INTO review_likes (review_id, user_id, is_positive)
                 KEY (review_id, user_id)
-                VALUES (:review_id, :user_id, FALSE)
-                """, params);
-        if (isPositiveYet == null) {
-            changeUsefulRating(params, DROP_UR);
-        } else if (isPositiveYet) {
-            changeUsefulRating(params, DOUBLE_DROP_UR);
-        }
-    }
-
-    @Override
-    public void removeLike(long id, long userId) {
-        MapSqlParameterSource params = new MapSqlParameterSource("review_id", id)
-                .addValue("user_id", userId);
-        jdbc.update("""
-                DELETE FROM review_likes
-                WHERE review_id = :review_id AND user_id = :user_id
+                VALUES (:review_id, :user_id, :is_positive)
                 """, params);
-        changeUsefulRating(params, DROP_UR);
+        updateUsefulRating(params);
     }
 
     @Override
-    public void removeDislike(long id, long userId) {
+    public void removeReaction(long id, long userId) {
         MapSqlParameterSource params = new MapSqlParameterSource("review_id", id)
                 .addValue("user_id", userId);
         jdbc.update("""
                 DELETE FROM review_likes
                 WHERE review_id = :review_id AND user_id = :user_id
                 """, params);
-        changeUsefulRating(params, UP_UR);
+        updateUsefulRating(params);
     }
 
     private MapSqlParameterSource getBaseParams(Review review) {
@@ -156,21 +124,15 @@ private MapSqlParameterSource getBaseParams(Review review) {
                 .addValue("is_Positive", review.getIsPositive());
     }
 
-    private Boolean isPositive(MapSqlParameterSource params) {
-        List<Boolean> list = jdbc.query("""
-                SELECT is_positive
-                FROM review_likes
-                WHERE review_id = :review_id AND user_id = :user_id
-                """, params, (rs, rowNum) -> rs.getBoolean("is_positive"));
-        return list.isEmpty() ? null : list.getFirst();
-    }
-
-    private void changeUsefulRating(MapSqlParameterSource params, int points) {
-        params.addValue("points", points);
+    private void updateUsefulRating(MapSqlParameterSource params) {
         jdbc.update("""
-                UPDATE reviews
-                SET useful_rating = useful_rating + :points
-                WHERE review_id = :review_id
+                UPDATE reviews r
+                SET useful_rating = COALESCE((
+                        SELECT SUM(CASE WHEN is_positive THEN 1 ELSE -1 END)
+                        FROM review_likes rl
+                        WHERE rl.review_id = r.review_id),
+                    0)
+                WHERE r.review_id = :review_id;
                 """, params);
     }
-}
+}

src/main/java/ru/yandex/practicum/filmorate/repository/review/ReviewRepository.java

@@ -1,5 +1,6 @@
 package ru.yandex.practicum.filmorate.repository.review;
 
+import ru.yandex.practicum.filmorate.model.Reaction;
 import ru.yandex.practicum.filmorate.model.Review;
 
 import java.util.Collection;
@@ -16,11 +17,7 @@ public interface ReviewRepository {
 
     Collection<Review> findAllByFilm(Long filmId, long count);
 
-    void setLike(long id, long userId);
+    void setReaction(long id, long userId, Reaction reaction);
 
-    void setDislike(long id, long userId);
-
-    void removeLike(long id, long userId);
-
-    void removeDislike(long id, long userId);
+    void removeReaction(long id, long userId);
 }

src/main/java/ru/yandex/practicum/filmorate/service/review/ReviewService.java

@@ -3,6 +3,7 @@
 import ru.yandex.practicum.filmorate.dto.review.NewReviewRequest;
 import ru.yandex.practicum.filmorate.dto.review.ReviewDto;
 import ru.yandex.practicum.filmorate.dto.review.UpdateReviewRequest;
+import ru.yandex.practicum.filmorate.model.Reaction;
 
 import java.util.Collection;
 
@@ -22,7 +23,5 @@ public interface ReviewService {
 
     void setDislike(long id, long userId);
 
-    void removeLike(long id, long userId);
-
-    void removeDislike(long id, long userId);
-}
+    void removeReaction(long id, long userId, Reaction reaction);
+}

src/main/java/ru/yandex/practicum/filmorate/service/review/ReviewServiceImpl.java

@@ -3,13 +3,12 @@
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
-import ru.yandex.practicum.filmorate.dto.review.NewReviewRequest;
-import ru.yandex.practicum.filmorate.dto.review.ReviewDto;
-import ru.yandex.practicum.filmorate.dto.review.UpdateReviewRequest;
+import ru.yandex.practicum.filmorate.dto.review.*;
 import ru.yandex.practicum.filmorate.exception.NotFoundException;
 import ru.yandex.practicum.filmorate.mapper.ReviewMapper;
 import ru.yandex.practicum.filmorate.model.EventType;
 import ru.yandex.practicum.filmorate.model.Operation;
+import ru.yandex.practicum.filmorate.model.Reaction;
 import ru.yandex.practicum.filmorate.model.Review;
 import ru.yandex.practicum.filmorate.repository.film.FilmRepository;
 import ru.yandex.practicum.filmorate.repository.review.ReviewRepository;
@@ -77,31 +76,26 @@ public void setLike(long id, long userId) {
         getReviewOrThrow(id);
         throwIfUserNotFound(userId);
         log.info("Like to review {} has been added by user {}", id, userId);
-        reviewRepository.setLike(id, userId);
+        reviewRepository.setReaction(id, userId, Reaction.LIKE);
     }
 
     @Override
     public void setDislike(long id, long userId) {
         getReviewOrThrow(id);
         throwIfUserNotFound(userId);
         log.info("Dislike to review {} has been added by user {}", id, userId);
-        reviewRepository.setDislike(id, userId);
+        reviewRepository.setReaction(id, userId, Reaction.DISLIKE);
     }
 
     @Override
-    public void removeLike(long id, long userId) {
+    public void removeReaction(long id, long userId, Reaction reaction) {
         getReviewOrThrow(id);
         throwIfUserNotFound(userId);
-        log.info("Like to review {} has been removed by user {}", id, userId);
-        reviewRepository.removeLike(id, userId);
-    }
-
-    @Override
-    public void removeDislike(long id, long userId) {
-        getReviewOrThrow(id);
-        throwIfUserNotFound(userId);
-        log.info("Dislike to review {} has been removed by user {}", id, userId);
-        reviewRepository.removeDislike(id, userId);
+        switch (reaction) {
+            case LIKE -> log.info("Like to review {} has been removed by user {}", id, userId);
+            case DISLIKE ->  log.info("Dislike to review {} has been removed by user {}", id, userId);
+        }
+        reviewRepository.removeReaction(id, userId);
     }
 
     private Review getReviewOrThrow(long id) {
@@ -118,4 +112,4 @@ private void throwIfFilmNotFound(long id) {
         filmRepository.findById(id)
                 .orElseThrow(NotFoundException.supplier("Film with filmId %d not found", id));
     }
-}
+}