package mqttclient

import (
    "errors"
    mqtt "github.com/eclipse/paho.mqtt.golang"
    "log"
    "sync"
)

var CONFIG = MqttConnectConfig{
    Broker:           "tcp://1.15.92.205:1883",
    User:             "admin",
    Password:         "houyaf1!",
    Certificate:      "",
    PrivateKey:       "",
    ClientId:         "clientID",
    WillEnabled:      false,
    WillTopic:        "",
    WillPayload:      "",
    WillQos:          0,
    Qos:              0,
    Retained:         false,
    OnConnect:        nil,
    OnConnectionLost: nil,
}

var ErrMqttInit = errors.New("MQTT初始化失败")

var (
    once       sync.Once
    mqttClient *MqttClient
)

func Instance() *MqttClient {
    once.Do(func() {
        mqttClient = NewMqttClient(CONFIG)
    })
    return mqttClient
}

func init() {
    if Instance() == nil {
        log.Fatal(ErrMqttInit)
    }
}

func Publish(topic string, payload []byte) error {
    return Instance().Publish(topic, payload)
}

func Subscribe(topics []string, onMessage mqtt.MessageHandler) error {
    return Instance().Subscribe(topics, onMessage)
}

func Unsubscribe(topics ...string) error {
    return Instance().Unsubscribe(topics...)
}