zt-closet-backend/internal/service/horoscope.go

package service

import (
	"context"
	"encoding/json"
	"log/slog"
	"time"

	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/global"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/dto"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/mysqldao"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/mysqlmodel"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/redisdao"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/pkg/errcode"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/pkg/tokenhub"
)

// HoroscopeService 今日运势业务服务。
type HoroscopeService struct {
	horoscopeDao *mysqldao.HoroscopeDao
	userDao      *mysqldao.UserDao
}

// NewHoroscopeService 创建运势服务。
func NewHoroscopeService() *HoroscopeService {
	return &HoroscopeService{
		horoscopeDao: mysqldao.NewHoroscopeDao(),
		userDao:      mysqldao.NewUserDao(),
	}
}

// GetToday 获取当前用户今日运势：由生日推算星座，Redis 优先、未命中回落 MySQL 并回填缓存。
func (s *HoroscopeService) GetToday(ctx context.Context, userID int64) (*dto.HoroscopeResponse, *errcode.Error) {
	ctx, span := global.Tracer.Start(ctx, "svc.HoroscopeGetToday")
	defer span.End()

	user, err := s.userDao.UserGetByID(ctx, userID)
	if err != nil {
		if isNotFound(err) {
			slog.WarnContext(ctx, "horoscope: user not found", "user_id", userID)
			return nil, errcode.UserNotFound
		}
		slog.ErrorContext(ctx, "horoscope: query user failed", "user_id", userID, "error", err)
		return nil, errcode.DatabaseError
	}
	if user.BirthDay == 0 {
		slog.InfoContext(ctx, "horoscope: birth day missing", "user_id", userID)
		return nil, errcode.InvalidParams.WithDetails("请先完善生日信息")
	}

	zodiac := zodiacByUnix(user.BirthDay)
	statDate := todayStatDate()

	// 1. Redis 优先。
	if data, cerr := redisdao.HoroscopeGet(ctx, zodiac, statDate); cerr == nil && len(data) > 0 {
		var response dto.HoroscopeResponse
		if uerr := json.Unmarshal(data, &response); uerr == nil {
			return &response, nil
		} else {
			slog.DebugContext(ctx, "horoscope: unmarshal cached data failed, fallback to db",
				"zodiac", zodiac, "error", uerr)
		}
	} else if cerr != nil {
		slog.DebugContext(ctx, "horoscope: cache read failed, fallback to db", "zodiac", zodiac, "error", cerr)
	}

	// 2. 回落 MySQL。
	h, derr := s.horoscopeDao.HoroscopeGetByZodiacAndDate(ctx, zodiac, statDate)
	if derr != nil {
		if isNotFound(derr) {
			// 今日运势尚未生成，异步触发兜底生成，本次返回未生成。
			slog.InfoContext(ctx, "horoscope: today data missing, trigger fallback generation", "zodiac", zodiac)
			tokenhub.EnsureTodayFortunes()
			return nil, errcode.HoroscopeNotFound
		}
		slog.ErrorContext(ctx, "horoscope: query db failed", "zodiac", zodiac, "error", derr)
		return nil, errcode.DatabaseError
	}

	response := buildHoroscopeResponse(h)

	// 回填缓存，TTL 至次日凌晨。
	if data, merr := json.Marshal(response); merr == nil {
		if serr := redisdao.HoroscopeSet(ctx, zodiac, statDate, data, ttlUntilNextMidnight()); serr != nil {
			slog.DebugContext(ctx, "horoscope: cache backfill failed", "zodiac", zodiac, "error", serr)
		}
	} else {
		slog.DebugContext(ctx, "horoscope: marshal response failed", "zodiac", zodiac, "error", merr)
	}

	return &response, nil
}

// buildHoroscopeResponse 将运势模型映射为响应。
func buildHoroscopeResponse(h *mysqlmodel.Horoscope) dto.HoroscopeResponse {
	return dto.HoroscopeResponse{
		StatDate:     h.StatDate,
		Zodiac:       h.Zodiac,
		OverallScore: h.OverallScore,
		LoveScore:    h.LoveScore,
		CareerScore:  h.CareerScore,
		WealthScore:  h.WealthScore,
		DailyText:    h.DailyText,
		LuckyColor:   h.LuckyColor,
		LuckyNumber:  h.LuckyNumber,
	}
}

// ttlUntilNextMidnight 计算到次日 0 点的时长，用于运势缓存过期。
func ttlUntilNextMidnight() time.Duration {
	now := time.Now()
	next := time.Date(now.Year(), now.Month(), now.Day()+1, 0, 0, 0, 0, now.Location())
	return next.Sub(now)
}

// zodiacByUnix 根据生日（秒级 unix 时间戳）计算星座（中文名，与运势数据对齐）。
func zodiacByUnix(birthUnix int64) string {
	t := time.Unix(birthUnix, 0)
	return zodiacByMonthDay(int(t.Month()), t.Day())
}

// zodiacByMonthDay 根据月日返回星座中文名。
func zodiacByMonthDay(month, day int) string {
	switch month {
	case 1:
		if day <= 19 {
			return "摩羯座"
		}
		return "水瓶座"
	case 2:
		if day <= 18 {
			return "水瓶座"
		}
		return "双鱼座"
	case 3:
		if day <= 20 {
			return "双鱼座"
		}
		return "白羊座"
	case 4:
		if day <= 19 {
			return "白羊座"
		}
		return "金牛座"
	case 5:
		if day <= 20 {
			return "金牛座"
		}
		return "双子座"
	case 6:
		if day <= 21 {
			return "双子座"
		}
		return "巨蟹座"
	case 7:
		if day <= 22 {
			return "巨蟹座"
		}
		return "狮子座"
	case 8:
		if day <= 22 {
			return "狮子座"
		}
		return "处女座"
	case 9:
		if day <= 22 {
			return "处女座"
		}
		return "天秤座"
	case 10:
		if day <= 23 {
			return "天秤座"
		}
		return "天蝎座"
	case 11:
		if day <= 22 {
			return "天蝎座"
		}
		return "射手座"
	case 12:
		if day <= 21 {
			return "射手座"
		}
		return "摩羯座"
	}
	return "摩羯座"
}