package user

import (
	"context"
	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/cmd/discuss/interanl/pkg/db/transaction"
	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/cmd/discuss/interanl/pkg/domain"
	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/pkg/contextdata"
	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/pkg/xerr"
	"time"

	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/cmd/discuss/api/internal/svc"
	"gitlab.fjmaimaimai.com/allied-creation/sumifcc-discuss/cmd/discuss/api/internal/types"

	"github.com/zeromicro/go-zero/core/logx"
)

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

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

func (l *MiniUserFollowLogic) MiniUserFollow(req *types.FollowRequest) (err error) {
	var (
		conn       = l.svcCtx.DefaultDBConn()
		user       *domain.User
		targetUser *domain.User
		userFollow *domain.UserFollow
		userToken  = contextdata.GetUserTokenFromCtx(l.ctx)
	)
	if user, err = l.svcCtx.UserRepository.FindOne(l.ctx, conn, userToken.UserId); err != nil {
		return xerr.NewErrMsgErr("用户不存在", err)
	}
	if targetUser, err = l.svcCtx.UserRepository.FindOne(l.ctx, conn, req.UserId); err != nil {
		return xerr.NewErrMsgErr("关注的用户不存在", err)
	}
	if userFollow, err = l.svcCtx.UserFollowRepository.FindOneUserFollowing(l.ctx, conn, user.Id, targetUser.Id); err == nil && userFollow != nil {
		return xerr.NewErrMsgErr("用户已关注", err)
	}
	if err = transaction.UseTrans(l.ctx, l.svcCtx.DB, func(ctx context.Context, conn transaction.Conn) error {
		if err = user.Follow(targetUser); err != nil {
			return err
		}
		if user, err = l.svcCtx.UserRepository.UpdateWithVersion(ctx, conn, user); err != nil {
			return err
		}
		if targetUser, err = l.svcCtx.UserRepository.UpdateWithVersion(ctx, conn, targetUser); err != nil {
			return err
		}
		userFollow = &domain.UserFollow{
			FromUserId: user.Id,
			ToUserId:   targetUser.Id,
			LastReadAt: time.Now().Unix(),
		}
		if userFollow, err = l.svcCtx.UserFollowRepository.Insert(ctx, conn, userFollow); err != nil {
			return err
		}
		return nil
	}, true); err != nil {
		return xerr.NewErrMsgErr("关注用户失败", err)
	}
	return nil
}