feat(interaction): 新增分集计数统计接口

fruitshorts-app-api/src/main/java/com/fruitshorts/app/controller/AppDramaController.java

@@ -3,7 +3,9 @@
 package com.fruitshorts.app.controller;
 
 import com.fruitshorts.app.service.AppCatalogService;
+import com.fruitshorts.app.service.AppEpisodeStatsService;
 import com.fruitshorts.app.vo.AppDramaDetailVO;
+import com.fruitshorts.app.vo.AppEpisodeStatsVO;
 import com.fruitshorts.common.pojo.Result;
 import com.fruitshorts.content.dal.entity.DramaEpisode;
 import com.fruitshorts.content.service.EpisodeService;
@@ -34,6 +36,7 @@ public class AppDramaController {
     private final PlaybackService playbackService;
     private final EpisodeService episodeService;
     private final CommentService commentService;
+    private final AppEpisodeStatsService appEpisodeStatsService;
 
     /** 详情：包含剧集列表，客户端进详情页一次请求即可渲染 */
     @Operation(summary = "短剧详情（含剧集列表，进详情页一次请求即可渲染）")
@@ -59,4 +62,11 @@ public class AppDramaController {
         vo.setCommentCount(commentService.countByEpisodes(List.of(id)).getOrDefault(id, 0L));
         return Result.ok(vo);
     }
+
+    /** 轻量计数快照：只读互动状态，不签发播放地址、不写票据缓存。 */
+    @Operation(summary = "播放页轻量计数与当前用户互动状态")
+    @GetMapping("/episodes/{id}/stats")
+    public Result<AppEpisodeStatsVO> stats(@PathVariable Long id) {
+        return Result.ok(appEpisodeStatsService.get(id, SecurityUtils.getUserIdOrNull()));
+    }
 }

fruitshorts-app-api/src/main/java/com/fruitshorts/app/service/AppEpisodeStatsService.java

@@ -0,0 +1,82 @@
+// Author: fruit.com.cn
+
+package com.fruitshorts.app.service;
+
+import com.fruitshorts.app.vo.AppEpisodeStatsVO;
+import com.fruitshorts.common.exception.ErrorCode;
+import com.fruitshorts.common.exception.ServiceException;
+import com.fruitshorts.content.dal.entity.Drama;
+import com.fruitshorts.content.dal.entity.DramaEpisode;
+import com.fruitshorts.content.service.DramaService;
+import com.fruitshorts.content.service.EpisodeService;
+import com.fruitshorts.interaction.service.CommentService;
+import com.fruitshorts.interaction.service.LikeService;
+import com.fruitshorts.playback.service.FavoriteService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/** 播放页只读计数快照；固定维度批量查询，不签发播放地址或票据。 */
+@Service
+@RequiredArgsConstructor
+public class AppEpisodeStatsService {
+
+    private final EpisodeService episodeService;
+    private final DramaService dramaService;
+    private final CommentService commentService;
+    private final LikeService likeService;
+    private final FavoriteService favoriteService;
+
+    public AppEpisodeStatsVO get(Long episodeId, Long userId) {
+        Map<Long, AppEpisodeStatsVO> stats = batch(List.of(episodeId), userId);
+        AppEpisodeStatsVO result = stats.get(episodeId);
+        if (result == null) {
+            throw new ServiceException(ErrorCode.DATA_NOT_FOUND, "剧集不存在或未上线");
+        }
+        return result;
+    }
+
+    /** 每类数据只查一次，供后续多集统计复用。 */
+    public Map<Long, AppEpisodeStatsVO> batch(Collection<Long> episodeIds, Long userId) {
+        if (episodeIds == null || episodeIds.isEmpty()) {
+            return Map.of();
+        }
+        List<DramaEpisode> episodes = episodeService.listPublishedByIds(episodeIds);
+        if (episodes.isEmpty()) {
+            return Map.of();
+        }
+        List<Long> normalizedIds = episodes.stream().map(DramaEpisode::getId).toList();
+        List<Long> dramaIds = episodes.stream().map(DramaEpisode::getDramaId).distinct().toList();
+        Map<Long, Long> commentCounts = commentService.countByEpisodes(normalizedIds);
+        Map<Long, Drama> dramas = new HashMap<>();
+        for (Drama drama : dramaService.listPublishedByIds(dramaIds)) {
+            dramas.put(drama.getId(), drama);
+        }
+        Set<Long> likedIds = likeService.likedTargetIds(
+                userId, LikeService.TYPE_EPISODE, normalizedIds);
+        Set<Long> favoriteDramaIds = favoriteService.favoriteDramaIds(userId, dramaIds);
+
+        Map<Long, AppEpisodeStatsVO> result = new HashMap<>();
+        for (DramaEpisode episode : episodes) {
+            Drama drama = dramas.get(episode.getDramaId());
+            if (drama == null) {
+                continue;
+            }
+            AppEpisodeStatsVO vo = new AppEpisodeStatsVO();
+            vo.setEpisodeId(episode.getId());
+            vo.setDramaId(episode.getDramaId());
+            vo.setLikeCount(episode.getLikeCount() == null ? 0L : episode.getLikeCount());
+            vo.setCommentCount(commentCounts.getOrDefault(episode.getId(), 0L));
+            vo.setFavoriteCount(drama.getFavoriteCount() == null ? 0L : drama.getFavoriteCount());
+            vo.setLiked(likedIds.contains(episode.getId()));
+            vo.setFavorited(favoriteDramaIds.contains(episode.getDramaId()));
+            result.put(episode.getId(), vo);
+        }
+        return result;
+    }
+}

fruitshorts-app-api/src/main/java/com/fruitshorts/app/vo/AppEpisodeStatsVO.java

@@ -0,0 +1,18 @@
+// Author: fruit.com.cn
+
+package com.fruitshorts.app.vo;
+
+import lombok.Data;
+
+/** 播放页轻量计数快照，不触发票据签发。 */
+@Data
+public class AppEpisodeStatsVO {
+
+    private Long episodeId;
+    private Long dramaId;
+    private Long likeCount;
+    private Long commentCount;
+    private Long favoriteCount;
+    private Boolean liked;
+    private Boolean favorited;
+}