CollectionService.java

package com.tanpu.community.service;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.tanpu.common.exception.BizException;
import com.tanpu.community.api.enums.CollectionTypeEnum;
import com.tanpu.community.api.enums.DeleteTagEnum;
import com.tanpu.community.dao.entity.community.CollectionEntity;
import com.tanpu.community.dao.mapper.community.CollectionMapper;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

@Service
public class CollectionService {
    @Resource
    private CollectionMapper collectionMapper;


    // 若不存在则新增，若存在则修改deleteTag
    @Transactional
    public void addIfNotExist(String themeId, String userId, CollectionTypeEnum type) {
        // 判断记录是否存在，无论是否删除
        CollectionEntity queryCollection = getTargetCollection(themeId, userId, type);
        if (queryCollection != null) {
            queryCollection.setDeleteTag(DeleteTagEnum.NOT_DELETED.getCode());
            queryCollection.setCollectionTime(LocalDateTime.now());
            collectionMapper.updateById(queryCollection);
        } else {
            CollectionEntity entity = CollectionEntity.builder()
                    .collectionType(type.getCode())
                    .userId(userId)
                    .targetId(themeId)
                    .collectionTime(LocalDateTime.now())
                    .build();

            collectionMapper.insert(entity);
        }
    }


    //根据用户、主题、类型查询未删除对象
    public CollectionEntity getNotDeleteTargetCollection(String targetId, String userId, CollectionTypeEnum type) {
        LambdaQueryWrapper<CollectionEntity> queryWrapper = new LambdaQueryWrapper<CollectionEntity>()
                .eq(CollectionEntity::getCollectionType, type.getCode())
                .eq(CollectionEntity::getUserId, userId)
                .eq(CollectionEntity::getTargetId, targetId)
                .eq(CollectionEntity::getDeleteTag, DeleteTagEnum.NOT_DELETED.getCode());
        return collectionMapper.selectOne(queryWrapper);
    }

    //根据用户、主题、类型查询记录，包括已删除对象
    public CollectionEntity getTargetCollection(String themeId, String userId, CollectionTypeEnum type) {
        LambdaQueryWrapper<CollectionEntity> queryWrapper = new LambdaQueryWrapper<CollectionEntity>()
                .eq(CollectionEntity::getCollectionType, type.getCode())
                .eq(CollectionEntity::getUserId, userId)
                .eq(CollectionEntity::getTargetId, themeId);
        return collectionMapper.selectOne(queryWrapper);
    }

    // 根据用户id和行为type获取target_id列表
    public Set<String> getListByUser(String userId, CollectionTypeEnum type) {
        return collectionMapper.selectList(new LambdaQueryWrapper<CollectionEntity>()
                .eq(CollectionEntity::getUserId,userId)
                .eq(CollectionEntity::getCollectionType, type.getCode())
                .eq(CollectionEntity::getDeleteTag, DeleteTagEnum.NOT_DELETED.getCode()))
                .stream().map(CollectionEntity::getTargetId).collect(Collectors.toSet());
    }


    // 统计单个对象(主题、评论)的数量（点赞、收藏）
    public Integer getCountByTypeAndId(String targetId, CollectionTypeEnum type) {
        return collectionMapper.selectCount((new LambdaQueryWrapper<CollectionEntity>()
                .eq(CollectionEntity::getTargetId, targetId)
                .eq(CollectionEntity::getCollectionType, type.getCode())
                .eq(CollectionEntity::getDeleteTag, DeleteTagEnum.NOT_DELETED.getCode())));
    }

    // 统计多个对象(主题、评论)的数量（点赞、收藏）
    public Integer getCountByTypeAndIds(List<String> targetIds, CollectionTypeEnum type) {
        return collectionMapper.selectCount((new LambdaQueryWrapper<CollectionEntity>()
                .in(CollectionEntity::getTargetId, targetIds)
                .eq(CollectionEntity::getCollectionType, type.getCode()))
                .eq(CollectionEntity::getDeleteTag, DeleteTagEnum.NOT_DELETED.getCode()));
    }
    //逻辑删除，修改delete_tag
    @Transactional
    public void delete(String themeId, String userId, CollectionTypeEnum type) {
        CollectionEntity queryCollection = getNotDeleteTargetCollection(themeId, userId, type);
        if (queryCollection != null) {
            queryCollection.setDeleteTag(DeleteTagEnum.DELETED.getCode());
            queryCollection.setUncollectionTime(LocalDateTime.now());
            collectionMapper.updateById(queryCollection);
        } else {
            throw new BizException("Collection对象未找到，themeId：" + themeId + ",userId：" + userId + ",type:" + type.getCode());
        }
    }
}