#coding:utf-8

import time
import json
from paho.mqtt import client as mqtt_client
import base64


broker = 'mqtt代理服务器地址'  # mqtt代理服务器地址
port = 1883     # 端口号
keepalive = 60     # 与代理通信之间允许的最长时间段（以秒为单位）
topic = "ug/SN1/uc/SN2/uplink"       #

client_id = '-1'  # 客户端id不能重复
client_password = 'password' # 客户端密码

def to_temhumidityco2tvoc(tem,humidity,co2,tvoc):
    '''将 需要发送的数据 转化为 传感器发送的数据格式'''
    length_tem = 2
    bytes_tem = b'\x03\x67'
    value_tem = (tem*10).to_bytes(length_tem, byteorder='little', signed=True)
    bytes_tem += value_tem[0:length_tem]

    length_humidity = 1
    bytes_humidity = b'\x04\x68'
    value_humidity = (humidity*2).to_bytes(length_humidity, byteorder='little')
    bytes_humidity += value_humidity[0:length_humidity]

    length_CO2 = 2
    bytes_CO2 = b'\x07\x7D'
    value_CO2 = (co2).to_bytes(length_CO2, byteorder='little')
    bytes_CO2 += value_CO2[0:length_CO2]

    length_tvoc = 2
    bytes_tvoc = b'\x08\x7D'
    value_tvoc = (tvoc).to_bytes(length_tvoc, byteorder='little')
    bytes_tvoc += value_tvoc[0:length_tvoc]

    bytes_temhumidityco2tvoc = bytes_tem + bytes_humidity + bytes_CO2 + bytes_tvoc
    res = base64.b64encode(bytes_temhumidityco2tvoc)
    return res

def get_info(tem,CO2,TVOC,humidity):
    '''传感器上报的数据内容'''
    temhumidityco2tvoc_byte = to_temhumidityco2tvoc(tem,humidity,CO2,TVOC)
    temhumidityco2tvoc_raw = str(temhumidityco2tvoc_byte,'UTF-8')

    info = {"version":2,"event":"status","data":{"raw":temhumidityco2tvoc_raw,"rssi":-73,"snr":11.2,"fPort":85,"bandwidth":125,"spreadFactor":7,"adr":1},"ts":int(time.time())}

    return json.dumps(info)


def connect_mqtt():
    '''连接mqtt代理服务器'''
    def on_connect(client, userdata, flags, rc):
        '''连接回调函数'''
        # 响应状态码为0表示连接成功
        if rc == 0:
            print("Connected to MQTT OK!")
        else:
            print("Failed to connect, return code %d\n", rc)
    # 连接mqtt代理服务器，并获取连接引用
    client = mqtt_client.Client(client_id)
    client.username_pw_set(client_id, client_password)
    client.on_connect = on_connect
    client.connect(broker, port, keepalive)


    return client

def publish(client):
    '''发布消息'''

    while True:
        '''每隔2秒发布一次服务器信息'''
        time.sleep(2)
        msg = get_info(-17, 1490, 399, 88)  # 参数含义顺序：（tem,CO2,TVOC,humidity)

        result = client.publish(topic, msg)

        status = result[0]
        status = status
        if status == 0:
            print("send succ")

        else:
            print("send fail")

def run():
    '''运行发布者'''

    client = connect_mqtt()
    # 运行一个线程来自动调用loop()处理网络事件, 非阻塞
    client.loop_start()
    publish(client)


if __name__ == '__main__':
    run()