feat(recommendations): 添加推荐条目计数功能

Author: LiggMax

flow-client/src/main/java/com/ligg/flowclient/mapper/BangumiSubjectMapper.java

@@ -28,4 +28,10 @@ List<SubjectRecommendationRow> selectRecommendedSubjects(@Param("subjectId") Int
                                                              @Param("metaTagNames") List<String> metaTagNames,
                                                              @Param("limit") int limit,
                                                              @Param("offset") int offset);
+
+    Integer countRecommendedSubjects(@Param("subjectId") Integer subjectId,
+                                     @Param("type") Integer type,
+                                     @Param("nsfw") Boolean nsfw,
+                                     @Param("tagNames") List<String> tagNames,
+                                     @Param("metaTagNames") List<String> metaTagNames);
 }

flow-client/src/main/java/com/ligg/flowclient/service/impl/BangumiServiceImpl.java

@@ -382,6 +382,12 @@ public SubjectsVo getRecommendedSubjects(Integer subjectId, int limit, int offse
         List<String> tagNames = parseSubjectTagNames(target.getTags());
         List<String> metaTagNames = parseMetaTagNames(target.getMetaTags());
         Integer releaseYear = parseReleaseYear(target.getDate());
+        Integer total = subjectMapper.countRecommendedSubjects(
+                subjectId,
+                target.getType(),
+                target.getNsfw(),
+                tagNames,
+                metaTagNames);
         List<SubjectRecommendationRow> rows = subjectMapper.selectRecommendedSubjects(
                 subjectId,
                 target.getType(),
@@ -394,12 +400,12 @@ public SubjectsVo getRecommendedSubjects(Integer subjectId, int limit, int offse
 
         if (rows == null || rows.isEmpty()) {
             vo.setData(Collections.emptyList());
-            vo.setTotal(0);
+            vo.setTotal(total);
             return vo;
         }
 
         vo.setData(rows.stream().map(this::toRecommendedSubject).toList());
-        vo.setTotal(rows.size());
+        vo.setTotal(total);
         return vo;
     }
 

flow-client/src/main/resources/mapper/BangumiSubjectMapper.xml

@@ -132,4 +132,47 @@
         limit #{limit} offset #{offset}
     </select>
 
+    <select id="countRecommendedSubjects" resultType="java.lang.Integer">
+        select count(*)
+        from (
+            select s.id,
+                   <choose>
+                       <when test="tagNames != null and tagNames.size() > 0">
+                           (
+                               select count(distinct subject_tag.name)
+                               from json_table(coalesce(s.tags, cast('[]' as json)),
+                                               '$[*]' columns (name varchar(128) path '$.name')) subject_tag
+                               where subject_tag.name in
+                               <foreach collection="tagNames" item="tagName" open="(" separator="," close=")">
+                                   #{tagName}
+                               </foreach>
+                           )
+                       </when>
+                       <otherwise>0</otherwise>
+                   </choose> as tag_matches,
+                   <choose>
+                       <when test="metaTagNames != null and metaTagNames.size() > 0">
+                           (
+                               select count(distinct subject_meta.name)
+                               from json_table(coalesce(s.meta_tags, cast('[]' as json)),
+                                               '$[*]' columns (name varchar(128) path '$')) subject_meta
+                               where subject_meta.name in
+                               <foreach collection="metaTagNames" item="metaTagName" open="(" separator="," close=")">
+                                   #{metaTagName}
+                               </foreach>
+                           )
+                       </when>
+                       <otherwise>0</otherwise>
+                   </choose> as meta_matches,
+                   s.`rank`
+            from bangumi_subject s
+            where s.id != #{subjectId}
+              and s.type = #{type}
+              and s.nsfw = #{nsfw}
+        ) candidate
+        where candidate.tag_matches > 0
+           or candidate.meta_matches > 0
+           or (candidate.`rank` is not null and candidate.`rank` > 0)
+    </select>
+
 </mapper>