slow_wild_backend/internal/logic/createpostlogic.go

package logic

import (
	"context"
	"slowwild/internal/constants"
	"slowwild/internal/svc"
	"strings"

	"git.banshen.xyz/huangguangrong/slow_wild_protobuff/slowwild/slowwildserver"

	"slowwild/internal/errorx"
	"slowwild/internal/model"
	"time"

	"slowwild/internal/utils"

	"github.com/spf13/cast"
	"github.com/zeromicro/go-zero/core/logx"
	"gorm.io/gorm"
)

type CreatePostLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

func NewCreatePostLogic(ctx context.Context, svcCtx *svc.ServiceContext) *CreatePostLogic {
	return &CreatePostLogic{
		ctx:    ctx,
		svcCtx: svcCtx,
		Logger: logx.WithContext(ctx),
	}
}

// 发布帖子
func (l *CreatePostLogic) CreatePost(in *slowwildserver.CreatePostReq) (*slowwildserver.CreatePostRsp, error) {
	userId, err := cast.ToInt64E(l.ctx.Value(constants.UserIDKey))
	if err != nil {
		return nil, errorx.NewCodeError(50001, "用户未登录")
	}
	if userId <= 0 || in.Content == "" {
		return nil, errorx.ErrInvalidParam
	}

	// 检查帖子类型是否合法
	if in.Type != 0 && in.Type != 1 {
		return nil, errorx.NewCodeError(20001, "帖子类型不合法")
	}

	// 开启事务
	err = l.svcCtx.UserModel.Transaction(l.ctx, func(tx *gorm.DB) error {
		postModel := model.NewPostModel(tx, l.svcCtx.Redis)
		postContentModel := model.NewPostContentModel(tx)
		userModel := model.NewUserModel(tx)
		tagModel := model.NewTagModel(tx, l.svcCtx.Redis)
		messageModel := model.NewMessageModel(tx)

		// 提取话题名称
		var tagNames []string
		for _, tag := range in.Tags {
			tagNames = append(tagNames, tag.Name)
		}

		// 检查话题是否存在
		existingTags, err := tagModel.FindByNames(l.ctx, tagNames)
		if err != nil {
			return err
		}

		// 找出不存在的话题名称
		existingTagMap := make(map[string]bool)
		for _, tag := range existingTags {
			existingTagMap[tag.Name] = true
		}

		// 需要新建的话题
		var newTags []*model.Tag
		for _, tag := range in.Tags {
			if !existingTagMap[tag.Name] {
				newTags = append(newTags, &model.Tag{
					Model: &model.Model{
						CreatedOn:  time.Now().Unix(),
						ModifiedOn: time.Now().Unix(),
					},
					UserId: userId,
					Name:   tag.Name,
					HotNum: 0,
				})
			}
		}

		// 创建新话题
		if len(newTags) > 0 {
			if err = tagModel.BatchCreate(l.ctx, newTags); err != nil {
				return err
			}
		}

		// 获取所有话题的ID
		var tagIds []int64
		for _, tag := range existingTags {
			tagIds = append(tagIds, tag.ID)
		}
		for _, tag := range newTags {
			tagIds = append(tagIds, tag.ID)
		}

		// 判断@用户是否重复，重复只发一次
		existUserMap := make(map[string]bool)
		if len(in.AtUserIds) > 0 {
			for _, id := range in.AtUserIds {
				existUserMap[cast.ToString(id)] = true
			}
		}
		atUserIds := make([]string, 0, len(existUserMap))
		if len(existUserMap) > 0 {
			for id := range existUserMap {
				atUserIds = append(atUserIds, id)
			}
		}

		// 创建帖子
		post := &model.Post{
			Model: &model.Model{
				CreatedOn:  time.Now().Unix(),
				ModifiedOn: time.Now().Unix(),
			},
			UserId:          userId,
			PostType:        in.Type,
			Visibility:      int8(in.Visibility),
			Tags:            strings.Join(tagNames, ","),
			Ip:              in.Ip,
			IpLoc:           in.IpLoc,
			WithUserIds:     strings.Join(atUserIds, ","),
			CommentCount:    0,
			CollectionCount: 0,
			UpvoteCount:     0,
			ShareCount:      0,
			IsTop:           0,
			IsEssence:       0,
			HotNum:          0,
		}

		// 创建帖子基本信息
		if err := postModel.Create(l.ctx, post); err != nil {
			return err
		}

		// 处理内容，生成摘要
		plainContent := utils.StripHTML(in.Content)
		contentSummary := utils.TruncateText(plainContent, 1000)

		// 创建帖子内容
		postContent := &model.PostContent{
			Model: &model.Model{
				CreatedOn:  time.Now().Unix(),
				ModifiedOn: time.Now().Unix(),
			},
			PostId:         post.ID,
			UserId:         userId,
			Title:          in.Title,
			Content:        in.Content,     // 保存原始内容
			ContentSummary: contentSummary, // 保存处理后的摘要
			PostVideoCover: in.VideoCover,
			PostCovers:     strings.Join(in.Images, ","),
			PostVideoUrl:   in.VideoUrl,
			Sort:           0,
		}

		if err := postContentModel.Create(l.ctx, postContent); err != nil {
			return err
		}

		// 创建帖子和话题的关联关系
		if err := tagModel.CreateTagWithPost(l.ctx, post.ID, tagIds); err != nil {
			return err
		}

		// 检查被艾特的用户是否存在
		if len(atUserIds) > 0 {
			atUsers, err := userModel.FindByIds(l.ctx, in.AtUserIds)
			if err != nil {
				return err
			}

			// 发送站内信给被艾特的用户
			for _, user := range atUsers {
				err = messageModel.SendNotification(l.ctx, userId, user.ID, 1, "你被艾特了", "你被艾特在一条动态中", post.ID, 0, 0)
				if err != nil {
					return err
				}
			}
		}

		// 增加用户的帖子数
		if err := userModel.IncrementTweetCount(l.ctx, userId); err != nil {
			return err
		}

		// 删除缓存
		postModel.ClearListCache(l.ctx)

		return nil
	})

	if err != nil {
		l.Logger.Errorf("发布帖子失败: %v", err)
		return nil, errorx.NewCodeError(20002, "发布帖子失败")
	}

	return &slowwildserver.CreatePostRsp{}, nil
}