package main

import (
	"crypto/tls"
	"sentinel/pkg/log"
	"time"

	mqtt "github.com/eclipse/paho.mqtt.golang"
)

type MQTTService struct {
	client  mqtt.Client
	handler func(topic string, payload []byte)
}

func NewMQTTService(broker, clientID, username, password string, keepalive int) *MQTTService {
	opts := mqtt.NewClientOptions()
	opts.AddBroker(broker)
	opts.SetClientID(clientID)
	opts.SetUsername(username)
	opts.SetPassword(password)
	opts.SetKeepAlive(time.Duration(keepalive) * time.Second)
	opts.SetTLSConfig(&tls.Config{InsecureSkipVerify: true})

	ms := &MQTTService{}
	opts.SetDefaultPublishHandler(func(c mqtt.Client, m mqtt.Message) {
		if ms.handler != nil {
			ms.handler(m.Topic(), m.Payload())
		}
	})
	opts.OnConnect = func(c mqtt.Client) {
		log.Println("物联网服务已连接")
	}
	opts.OnConnectionLost = func(c mqtt.Client, err error) {
		log.Println("物联网服务已断开：", err)
	}

	ms.client = mqtt.NewClient(opts)
	return ms
}

func (m *MQTTService) Connect() error {
	token := m.client.Connect()
	if token.Wait() && token.Error() != nil {
		return token.Error()
	}
	return nil
}

func (m *MQTTService) Subscribe(topic string, qos byte) error {
	token := m.client.Subscribe(topic, qos, nil)
	if token.Wait() && token.Error() != nil {
		return token.Error()
	}
	log.Println("物联网服务消息订阅：", topic)
	return nil
}

func (m *MQTTService) Publish(topic string, qos byte, retained bool, payload interface{}) error {
	token := m.client.Publish(topic, qos, retained, payload)
	token.Wait()
	return token.Error()
}

func (m *MQTTService) SetMessageHandler(h func(topic string, payload []byte)) {
	m.handler = h
}

func (m *MQTTService) Close() {
	if m.client != nil {
		m.client.Disconnect(250)
	}
}