增加动物笔记瀑布流接口

src/main/java/com/youlai/boot/mini/controller/StrayAnimalController.java

@@ -14,6 +14,8 @@ import com.youlai.boot.mini.model.form.NoteCollectForm;
 import com.youlai.boot.mini.model.form.NoteLikeForm;
 import com.youlai.boot.mini.model.form.StrayAnimalForm;
 import com.youlai.boot.mini.model.query.OwnStrayAnimalQuery;
+import com.youlai.boot.mini.model.query.WaterfallQuery;
+import com.youlai.boot.mini.model.vo.WaterfallResult;
 import com.youlai.boot.mini.model.vo.SaveStrayAnimalVO;
 import com.youlai.boot.mini.model.vo.StrayAnimalDetailsVO;
 import com.youlai.boot.mini.model.vo.StrayAnimalShortVO;
@@ -175,7 +177,15 @@ public class StrayAnimalController {
         return Result.success(result);
     }
 
-    //获取流浪动物笔记瀑布流
+    @Operation(summary = "获取流浪动物笔记瀑布流")
+    @GetMapping(value = "/note/waterfall")
+    public Result<WaterfallResult<StrayAnimalShortVO>> getWaterfall(
+        @Valid WaterfallQuery query
+    ) {
+        Long userId = SecurityUtils.getUserId();
+        WaterfallResult<StrayAnimalShortVO> result = strayAnimalService.getWaterfall(query, userId);
+        return Result.success(result);
+    }
 
     //增加浏览量
 

src/main/java/com/youlai/boot/mini/mapper/MiniStrayAnimalMapper.java

@@ -30,4 +30,6 @@ public interface MiniStrayAnimalMapper extends BaseMapper<MiniStrayAnimal> {
     StrayAnimalDetailsVO getStrayAnimalDetails(@Param("animalUuid") String animalUuid, @Param("miniUserId") Long miniUserId);
 
     List<StrayAnimalNearbyVO> listByMapBounds(MapSearchDTO mapSearch);
+
+    List<StrayAnimalShortVO> getWaterfall(@Param("cursor") Long cursor, @Param("pageSize") Integer pageSize, @Param("animalType") String animalType, @Param("miniUserId") Long miniUserId);
 }

src/main/java/com/youlai/boot/mini/model/query/WaterfallQuery.java

@@ -0,0 +1,19 @@
+package com.youlai.boot.mini.model.query;
+
+import com.youlai.boot.common.base.BaseQuery;
+import io.swagger.v3.oas.annotations.media.Schema;
+import jakarta.validation.constraints.Max;
+import jakarta.validation.constraints.Min;
+import lombok.Data;
+
+@Data
+@Schema(description = "瀑布流查询参数")
+public class WaterfallQuery extends BaseQuery {
+
+    @Schema(description = "游标（上一页最后一条的ID，首次请求不传）", example = "100")
+    private Long cursor;
+
+    @Schema(description = "动物类型筛选（cat-猫 dog-狗 other-其他）", example = "cat")
+    private String animalType;
+
+}

src/main/java/com/youlai/boot/mini/model/vo/StrayAnimalShortVO.java

@@ -7,6 +7,9 @@ import lombok.Data;
 @Data
 public class StrayAnimalShortVO {
 
+    @Schema(description = "笔记ID（仅用于瀑布流游标，前端不需要展示）", hidden = true)
+    private Long id;
+
     @Schema(description = "作者uuid", example = "true")
     private String authorUuid;
 

src/main/java/com/youlai/boot/mini/model/vo/WaterfallResult.java

@@ -0,0 +1,28 @@
+package com.youlai.boot.mini.model.vo;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+import lombok.Data;
+
+import java.util.List;
+
+@Data
+@Schema(description = "瀑布流返回结果")
+public class WaterfallResult<T> {
+
+    @Schema(description = "数据列表")
+    private List<T> list;
+
+    @Schema(description = "下一页游标（传null表示没有更多了）", example = "100")
+    private Long nextCursor;
+
+    @Schema(description = "是否最后一页", example = "false")
+    private Boolean isLastPage;
+
+    public static <T> WaterfallResult<T> of(List<T> list, Long nextCursor, boolean isLastPage) {
+        WaterfallResult<T> result = new WaterfallResult<>();
+        result.setList(list);
+        result.setNextCursor(nextCursor);
+        result.setIsLastPage(isLastPage);
+        return result;
+    }
+}

src/main/java/com/youlai/boot/mini/service/StrayAnimalService.java

@@ -9,8 +9,11 @@ import com.youlai.boot.mini.model.dto.MapSearchDTO;
 import com.youlai.boot.mini.model.entity.MiniStrayAnimal;
 import com.youlai.boot.mini.model.form.NoteCollectForm;
 import com.youlai.boot.mini.model.form.NoteLikeForm;
+import com.youlai.boot.mini.model.form.NoteCollectForm;
 import com.youlai.boot.mini.model.form.StrayAnimalForm;
 import com.youlai.boot.mini.model.query.OwnStrayAnimalQuery;
+import com.youlai.boot.mini.model.query.WaterfallQuery;
+import com.youlai.boot.mini.model.vo.WaterfallResult;
 import com.youlai.boot.mini.model.vo.SaveStrayAnimalVO;
 import com.youlai.boot.mini.model.vo.StrayAnimalDetailsVO;
 import com.youlai.boot.mini.model.vo.StrayAnimalNearbyVO;
@@ -48,5 +51,7 @@ public interface StrayAnimalService extends IService<MiniStrayAnimal> {
     Map<String, Object> toggleNoteLike(NoteLikeForm form, Long userId);
 
     Map<String, Object> toggleNoteCollect(NoteCollectForm form, Long userId);
+
+    WaterfallResult<StrayAnimalShortVO> getWaterfall(WaterfallQuery query, Long userId);
 }
 

src/main/java/com/youlai/boot/mini/service/impl/StrayAnimalServiceImpl.java

@@ -38,6 +38,7 @@ import com.youlai.boot.mini.model.entity.MiniStrayAnimalNote;
 import com.youlai.boot.mini.model.entity.MiniStrayAnimalNoteMedia;
 import com.youlai.boot.mini.model.form.StrayAnimalForm;
 import com.youlai.boot.mini.model.query.OwnStrayAnimalQuery;
+import com.youlai.boot.mini.model.query.WaterfallQuery;
 import com.youlai.boot.mini.model.vo.*;
 import com.youlai.boot.mini.service.MiniPointRecordService;
 import com.youlai.boot.mini.service.StrayAnimalService;
@@ -774,4 +775,55 @@ public class StrayAnimalServiceImpl extends ServiceImpl<MiniStrayAnimalMapper, M
         return result;
     }
 
+    @Override
+    public WaterfallResult<StrayAnimalShortVO> getWaterfall(WaterfallQuery query, Long userId) {
+        // 1. 设置默认值，查 N+1 条
+        int pageSize = query.getPageSize();
+        int querySize = pageSize + 1;
+
+        // 2. 从DB查询 N+1 条数据
+        List<StrayAnimalShortVO> list = miniStrayAnimalMapper.getWaterfall(
+                query.getCursor(),
+                querySize,
+                query.getAnimalType(),
+                userId
+        );
+
+        // 3. 设置默认图片（如果没有封面图）
+        if (list != null && !list.isEmpty()) {
+            list.forEach(item -> {
+                if (StrUtil.isBlank(item.getFirstImageUrl())) {
+                    switch (item.getAnimalType()) {
+                        case "cat":
+                            item.setFirstImageUrl(getDefaultCatCoverHost() + "/default_cat.png");
+                            break;
+                        case "dog":
+                            item.setFirstImageUrl(getDefaultCatCoverHost() + "/default_dog.png");
+                            break;
+                        default:
+                            item.setFirstImageUrl(getDefaultCatCoverHost() + "/default_other.png");
+                            break;
+                    }
+                }
+            });
+        }
+
+        // 4. 计算下一页游标（N+1 方案：如果返回数量 > pageSize 说明有下一页，取前 pageSize 条）
+        Long nextCursor = null;
+        boolean isLastPage = true;
+        List<StrayAnimalShortVO> resultList = list;
+
+        if (list != null && !list.isEmpty()) {
+            if (list.size() > pageSize) {
+                // 取前 pageSize 条
+                resultList = list.subList(0, pageSize);
+                // 用第 pageSize 条的 id 作为游标
+                nextCursor = list.get(pageSize - 1).getId();
+                isLastPage = false;
+            }
+        }
+
+        return WaterfallResult.of(resultList, nextCursor, isLastPage);
+    }
+
 }

src/main/resources/mapper/mini/MiniStrayAnimalMapper.xml

@@ -291,5 +291,69 @@
         </if>
     </select>
 
+    <!-- 瀑布流查询 -->
+    <select id="getWaterfall" resultType="com.youlai.boot.mini.model.vo.StrayAnimalShortVO" databaseId="mysql">
+        WITH first_image AS (
+            SELECT
+                m.note_id,
+                m.source_url,
+                ROW_NUMBER() OVER (
+                    PARTITION BY m.note_id
+                    ORDER BY m.id ASC
+                ) AS rn
+            FROM mini_stray_animal_note_media m
+            WHERE m.media_type = 'image'
+              AND m.is_deleted = 0
+        )
+        SELECT
+            n.id,
+            u.uuid AS authorUuid,
+            u.nickname AS authorName,
+            u.avatar AS authorAvatar,
+            a.uuid AS animalUuid,
+            n.uuid AS animalNoteUuid,
+            a.animal_type,
+            fi.source_url AS firstImageUrl,
+            n.title,
+            n.content,
+            n.visibility,
+            n.view_count,
+            n.like_count,
+            n.comment_count,
+            n.collect_count,
+            <if test="miniUserId != null">
+                -- 当前用户是否点赞
+                EXISTS (
+                    SELECT 1
+                    FROM mini_stray_animal_note_like l
+                    WHERE l.note_id = n.id
+                      AND l.mini_user_id = #{miniUserId}
+                      AND l.is_deleted = 0
+                ) AS isLiked,
+                -- 当前用户是否收藏
+                EXISTS (
+                    SELECT 1
+                    FROM mini_stray_animal_note_collect c
+                    WHERE c.note_id = n.id
+                      AND c.mini_user_id = #{miniUserId}
+                      AND c.is_deleted = 0
+                ) AS isCollected,
+            </if>
+            a.audit_status
+        FROM mini_stray_animal a
+        INNER JOIN sys_user u ON a.mini_user_id = u.id
+        LEFT JOIN mini_stray_animal_note n ON n.stray_animal_id = a.id
+        LEFT JOIN first_image fi ON fi.note_id = n.id AND fi.rn = 1
+        WHERE n.is_deleted = 0
+          AND a.is_deleted = 0
+          <if test="cursor != null">
+            AND n.id &lt; #{cursor}
+          </if>
+          <if test="animalType != null and animalType != ''">
+            AND a.animal_type = #{animalType}
+          </if>
+        ORDER BY n.id DESC
+        LIMIT #{pageSize}
+    </select>
 
 </mapper>