package crontab

import (
	"apiServer_service/utils/logger"
	"fmt"
	"sync"

	"github.com/robfig/cron/v3"
)

// Task 定时任务接口
type Task interface {
	Name() string
	Spec() string
	Run()
}

type Scheduler struct {
	cron  *cron.Cron
	tasks []Task
	mu    sync.RWMutex
}

var (
	defaultScheduler *Scheduler
	once             sync.Once
)

func DefaultScheduler() *Scheduler {
	once.Do(func() {
		defaultScheduler = NewScheduler()
	})
	return defaultScheduler
}

func NewScheduler() *Scheduler {
	return &Scheduler{
		cron: cron.New(cron.WithSeconds()),
	}
}

func (s *Scheduler) Register(task Task) {
	s.mu.Lock()
	defer s.mu.Unlock()

	entryID, err := s.cron.AddFunc(task.Spec(), func() {
		logger.CronInfo("Cron", fmt.Sprintf("执行任务: %s", task.Name()))
		defer func() {
			if r := recover(); r != nil {
				logger.CronError("Cron", fmt.Sprintf("任务 %s panic: %v", task.Name(), r))
			}
		}()
		task.Run()
	})
	if err != nil {
		logger.CronError("Cron", fmt.Sprintf("注册任务失败: %s, %v", task.Name(), err))
		return
	}
	s.tasks = append(s.tasks, task)
	logger.CronInfo("Cron", fmt.Sprintf("注册任务: %s [%s] (id=%d)", task.Name(), task.Spec(), entryID))
}

func (s *Scheduler) Start() {
	logger.CronInfo("Cron", fmt.Sprintf("调度器启动，已注册 %d 个任务", len(s.tasks)))
	s.cron.Start()
}

func (s *Scheduler) Stop() {
	logger.CronInfo("Cron", "调度器停止")
	ctx := s.cron.Stop()
	<-ctx.Done()
}

func (s *Scheduler) RunOnce() {
	s.mu.RLock()
	defer s.mu.RUnlock()
	for _, task := range s.tasks {
		logger.CronInfo("Cron", fmt.Sprintf("立即执行: %s", task.Name()))
		task.Run()
	}
}

func (s *Scheduler) RunTaskByName(name string) bool {
	s.mu.RLock()
	defer s.mu.RUnlock()
	for _, task := range s.tasks {
		if task.Name() == name {
			task.Run()
			return true
		}
	}
	return false
}

func (s *Scheduler) GetTasks() []Task {
	s.mu.RLock()
	defer s.mu.RUnlock()
	return s.tasks
}