package mqtt

import (
	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/logger"
	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/message_queue/common"
	"git.sxidc.com/go-tools/utils/strutils"
	mqtt "github.com/eclipse/paho.mqtt.golang"
	"github.com/pkg/errors"
	"sync"
	"time"
)

type MessageQueue struct {
	mqttClient mqtt.Client

	topicGroupMapHandlerMutex *sync.RWMutex
	topicGroupHandlerMap      map[string]map[string]common.MessageHandler
}

func New(address string, userName string, password string) (*MessageQueue, error) {
	clientID := "baize-" + strutils.SimpleUUID()[0:8]

	mqttClient := mqtt.NewClient(mqtt.NewClientOptions().
		SetAutoReconnect(true).
		SetUsername(password).
		SetPassword(userName).
		AddBroker(address).
		SetClientID(clientID).
		SetOrderMatters(false).
		SetWill(clientID+"/will", "dead", 2, true))

	token := mqttClient.Connect()

	if !token.WaitTimeout(20 * time.Second) {
		return nil, errors.New("连接超时")
	}

	if token.Error() != nil {
		return nil, token.Error()
	}

	for !mqttClient.IsConnected() {
		logger.GetInstance().Info("等待连接MQTT代理...")
		time.Sleep(1 * time.Second)
	}

	return &MessageQueue{
		mqttClient:                mqttClient,
		topicGroupMapHandlerMutex: &sync.RWMutex{},
		topicGroupHandlerMap:      make(map[string]map[string]common.MessageHandler),
	}, nil
}

func Destroy(messageQueue *MessageQueue) {
	if messageQueue == nil {
		return
	}

	messageQueue.mqttClient.Disconnect(250)
	messageQueue.mqttClient = nil

	messageQueue = nil
}

func (messageQueue *MessageQueue) Subscribe(group string, topic string, handler common.MessageHandler) error {
	messageQueue.topicGroupMapHandlerMutex.Lock()
	defer messageQueue.topicGroupMapHandlerMutex.Unlock()

	token := messageQueue.mqttClient.Subscribe(topic, 1, func(client mqtt.Client, message mqtt.Message) {
		messageQueue.topicGroupMapHandlerMutex.RLock()
		defer messageQueue.topicGroupMapHandlerMutex.RUnlock()

		for _, groupHandler := range messageQueue.topicGroupHandlerMap[topic] {
			go groupHandler(messageQueue, message.Topic(), string(message.Payload()))
		}
	})

	if !token.WaitTimeout(20 * time.Second) {
		return errors.New("订阅超时")
	}

	if token.Error() != nil {
		return token.Error()
	}

	groupHandlerMap, ok := messageQueue.topicGroupHandlerMap[topic]
	if !ok {
		groupHandlerMap = make(map[string]common.MessageHandler)
	}

	h, ok := groupHandlerMap[group]
	if !ok {
		h = handler
	}

	groupHandlerMap[group] = h
	messageQueue.topicGroupHandlerMap[topic] = groupHandlerMap

	return nil
}

func (messageQueue *MessageQueue) UnSubscribe(group string, topic string) error {
	messageQueue.topicGroupMapHandlerMutex.Lock()
	defer messageQueue.topicGroupMapHandlerMutex.Unlock()

	groupHandlerMap, ok := messageQueue.topicGroupHandlerMap[topic]
	if !ok {
		return nil
	}

	_, ok = groupHandlerMap[group]
	if !ok {
		return nil
	}

	delete(groupHandlerMap, group)

	if len(groupHandlerMap) == 0 {
		delete(messageQueue.topicGroupHandlerMap, topic)
	} else {
		messageQueue.topicGroupHandlerMap[topic] = groupHandlerMap
	}

	token := messageQueue.mqttClient.Unsubscribe(topic)

	if !token.WaitTimeout(20 * time.Second) {
		return errors.New("取消订阅超时")
	}

	if token.Error() != nil {
		return token.Error()
	}

	return nil
}

func (messageQueue *MessageQueue) Publish(topic string, data string) error {
	token := messageQueue.mqttClient.Publish(topic, 1, false, data)

	if !token.WaitTimeout(20 * time.Second) {
		return errors.New("发布订阅超时")
	}

	if token.Error() != nil {
		return token.Error()
	}

	return nil
}