package internal

import (
	"fmt"
	"github.com/streadway/amqp"
	"sparrow/pkg/rpcs"
	"sparrow/pkg/rule"
	"sparrow/pkg/server"
	"time"
)

type TimerService struct {
	tc                 *rule.TaskLifecycleConsumer
	host               string
	done               chan bool
	isReady            bool
	conn               *amqp.Connection
	notifyCloseChannel chan *amqp.Error
	notifyChanClose    chan *amqp.Error
	ch                 *amqp.Channel
	reconnectChan      chan struct{}
	taskSchedule       *TaskSchedule
}

func NewTimerService(host string) *TimerService {
	ts := &TimerService{
		host:          host,
		done:          make(chan bool),
		taskSchedule:  NewTaskSchedule(),
		reconnectChan: make(chan struct{}),
	}
	go ts.handleReconnect()
	return ts
}

func (s *TimerService) Ping(args string, result rpcs.ReplyEmptyResult) error {
	return nil
}

func (s *TimerService) init(conn *amqp.Connection) error {
	ch, err := conn.Channel()
	if err != nil {
		return err
	}
	s.ch = ch
	tc := rule.NewTaskLifecycleConsumer(ch)
	err = tc.Init()
	if err != nil {
		return err
	}
	err = tc.Start()
	if err != nil {
		return err
	}
	tc.SetExternalConsumer(s.taskSchedule)
	s.tc = tc
	s.notifyChanClose = make(chan *amqp.Error)
	s.ch.NotifyClose(s.notifyChanClose)
	s.isReady = true
	return s.initTaskConsumer()
}

// 初始化任务消费者
func (s *TimerService) initTaskConsumer() error {
	q, err := s.ch.QueueDeclare("", false, true, false, false, nil)
	if err != nil {
		return err
	}
	err = s.ch.QueueBind(q.Name, "*.*.timer", rule.TaskExchange, false, nil)
	if err != nil {
		return err
	}
	msgChan, err := s.ch.Consume(q.Name, "", false, false, false, false, nil)
	if err != nil {
		return err
	}
	go func() {
		for {
			select {
			case <-s.reconnectChan:
				return
			case msg := <-msgChan:
				s.handleTimerTask(msg.Body)
			}
		}
	}()
	return nil
}

func (s *TimerService) handleTimerTask(msg []byte) {
	err := s.taskSchedule.AddTask(msg)
	if err != nil {
		server.Log.Errorf("create task error :%s", err.Error())
	}
}

func (s *TimerService) connect() (*amqp.Connection, error) {
	conn, err := amqp.Dial(s.host)
	if err != nil {
		return nil, err
	}
	s.conn = conn
	s.notifyCloseChannel = make(chan *amqp.Error)
	s.conn.NotifyClose(s.notifyCloseChannel)
	return conn, err
}
func (s *TimerService) handleReconnect() {
	for {
		s.isReady = false
		conn, err := s.connect()
		fmt.Println("handleReconnect")
		if err != nil {
			server.Log.Errorf("connect to rabbitmq error:%s", err.Error())
			select {
			case <-s.done:
				return
			case <-time.After(4 * time.Second):
			}
			continue
		}
		if done := s.handleReInit(conn); done {
			break
		}
	}
}
func (s *TimerService) handleReInit(conn *amqp.Connection) bool {
	for {
		s.isReady = false
		err := s.init(conn)
		if err != nil {
			select {
			case <-s.done:
				return true
			case <-time.After(time.Second * 3):
			}
			continue
		}
		select {
		case <-s.done:
			return true
		case err := <-s.notifyCloseChannel:
			fmt.Println("Connection closed. Reconnecting..." + err.Error())
			close(s.reconnectChan)
			return false
		case err := <-s.notifyChanClose:
			fmt.Println("Channel closed. Re-running init..." + err.Error())
		}
	}
}