mce/internal/service/level_service.go

package service

import (
	"fmt"
	"time"

	"metazone.cc/metalab/internal/model"
)

// LevelService 积分与等级业务逻辑
type LevelService struct {
	userRepo  userLevelStore
	checkRepo checkInStore
	taskRepo  taskStore
	notifSvc  levelNotifier
}

// NewLevelService 构造函数
func NewLevelService(userRepo userLevelStore, checkRepo checkInStore, taskRepo taskStore, notifSvc levelNotifier) *LevelService {
	return &LevelService{userRepo: userRepo, checkRepo: checkRepo, taskRepo: taskRepo, notifSvc: notifSvc}
}

// GetLevel 获取用户当前等级、经验值和今日签到状态
func (s *LevelService) GetLevel(userID uint) (level int, exp int, checkedIn bool, err error) {
	user, err := s.userRepo.FindByID(userID)
	if err != nil {
		return 0, 0, false, err
	}

	loc, _ := time.LoadLocation("Asia/Shanghai")
	now := time.Now().In(loc)
	today := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, loc)
	_, err = s.checkRepo.FindCheckIn(userID, today)
	checkedIn = err == nil

	return model.GetLevelByExp(user.Exp), user.Exp, checkedIn, nil
}

// AddExp 增加经验值，自动检查升级并发送通知
// 返回：新经验值、是否升级、错误
func (s *LevelService) AddExp(userID uint, delta int) (newExp int, levelUp bool, err error) {
	if delta <= 0 {
		user, err := s.userRepo.FindByID(userID)
		if err != nil {
			return 0, false, err
		}
		return user.Exp, false, nil
	}

	// 先查旧等级
	user, err := s.userRepo.FindByID(userID)
	if err != nil {
		return 0, false, err
	}
	oldLevel := model.GetLevelByExp(user.Exp)

	// 原子增加经验值
	if err := s.userRepo.AddExp(userID, delta); err != nil {
		return 0, false, err
	}

	// 查新等级
	user, err = s.userRepo.FindByID(userID)
	if err != nil {
		return 0, false, err
	}
	newLevel := model.GetLevelByExp(user.Exp)

	if newLevel > oldLevel {
		levelUp = true
		if s.notifSvc != nil {
			_ = s.notifSvc.Create(userID, model.NotifyLevelUp,
				"等级提升",
				fmt.Sprintf("恭喜您！您的等级已提升至 %s", model.GetLevelName(newLevel)),
				nil)
		}
	}

	return user.Exp, levelUp, nil
}

// CheckIn 执行签到（基于 Asia/Shanghai 自然日严格防重）
// 返回：是否成功签到、新经验值、是否升级、错误
func (s *LevelService) CheckIn(userID uint) (checkedIn bool, newExp int, levelUp bool, err error) {
	loc, _ := time.LoadLocation("Asia/Shanghai")
	now := time.Now().In(loc)
	today := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, loc)

	// 检查今日是否已签到
	_, err = s.checkRepo.FindCheckIn(userID, today)
	if err == nil {
		// 已签到
		user, _ := s.userRepo.FindByID(userID)
		if user != nil {
			return false, user.Exp, false, nil
		}
		return false, 0, false, nil
	}

	// 创建签到记录
	ci := &model.UserCheckIn{
		UserID: userID,
		Date:   today,
	}
	if err := s.checkRepo.CreateCheckIn(ci); err != nil {
		// 唯一索引冲突 → 已签到
		user, _ := s.userRepo.FindByID(userID)
		if user != nil {
			return false, user.Exp, false, nil
		}
		return false, 0, false, nil
	}

	// 增加经验值
	newExp, levelUp, err = s.AddExp(userID, 5)
	return true, newExp, levelUp, err
}

// CompleteTask 完成首次任务（严格防重）
// 返回：新经验值、是否升级、错误
func (s *LevelService) CompleteTask(userID uint, taskType string) (newExp int, levelUp bool, err error) {
	// 检查是否已完成
	_, err = s.taskRepo.FindTask(userID, taskType)
	if err == nil {
		// 已完成过，不重复奖励
		user, _ := s.userRepo.FindByID(userID)
		if user != nil {
			return user.Exp, false, nil
		}
		return 0, false, nil
	}

	// 创建任务记录
	task := &model.UserTask{
		UserID:   userID,
		TaskType: taskType,
	}
	if err := s.taskRepo.CreateTask(task); err != nil {
		// 唯一索引冲突 → 已完成
		user, _ := s.userRepo.FindByID(userID)
		if user != nil {
			return user.Exp, false, nil
		}
		return 0, false, nil
	}

	// 增加经验值
	return s.AddExp(userID, 10)
}