"""
MicroPython IoT Weather Station Example for Wokwi.com

To view the data:

1. Go to http://www.hivemq.com/demos/websocket-client/
2. Click "Connect"
3. Under Subscriptions, click "Add New Topic Subscription"
4. In the Topic field, type "wokwi-weather" then click "Subscribe"

Now click on the DHT22 sensor in the simulation,
change the temperature/humidity, and you should see
the message appear on the MQTT Broker, in the "Messages" pane.

Copyright (C) 2022, Uri Shaked

https://wokwi.com/arduino/projects/322577683855704658
"""

import network
import time
from machine import Pin,I2C
import dht
import ujson
from umqtt.simple import MQTTClient
import ssd1306 
import machine
from machine import Timer



# ESP32 Pin assignment 
i2c = I2C(0, scl=Pin(22), sda=Pin(21))

oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)
oled.text('Hello, Wokwi!', 10, 10)      
oled.show()

# MQTT Server Parameters
MQTT_CLIENT_ID = "zhenggongni2201035012"
MQTT_BROKER    = "broker.emqx.io"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_TOPIC     = "zhenggongni2201035012"

TOPIC1 = b"led2206054024" #灯控主题，为了避免主题和其他同学一样，末尾需要添加自己的学号
TOPIC2 = b"pwmled2206054024"
sensor = dht.DHT22(Pin(15))

led_blue = machine.PWM(machine.Pin(2), freq=1) # 设置 GPIO2 为PWM输出
led_blue.duty(1023)

#连接WiFi配置
print("Connecting to WiFi", end="")
sta_if = network.WLAN(network.STA_IF)
sta_if.active(True)
sta_if.connect('Wokwi-GUEST', '')
while not sta_if.isconnected():
  print(".", end="")
  time.sleep(0.1)
print(" Connected!")


print("Connecting to MQTT server... ", end="")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.connect()

print("Connected!")

prev_weather = ""
while True:
  print("Measuring weather conditions... ", end="")
  sensor.measure() 
  msg_data= {
    "temp": sensor.temperature(),
    "humidity": sensor.humidity(),
  }
  message=ujson.dumps(msg_data)
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    oled.fill(0)
    oled.text('temp:%.1f dC'%(msg_data["temp"]),10,20)
    oled.text('humidity:%.1f'%(msg_data["humidity"]),10,30)
    oled.show()
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")

def sub_cb(topic,msg):
    global pwm_old,pwmval
    if topic==TOPIC1:
        print((topic,msg))
        if msg==b"on":
            pwmval=0
            led_blue.duty(pwmval)
        elif msg==b"off":
            pwmval=1023
            led_blue.duty(pwmval)
    if topic==TOPIC2:
        pwmval=int(((100-int(msg))/100)*1023)
        if pwmval>1023:pwmval=1023
        if pwmval<0:pwmval=0
        print(topic,pwmval)
        led_blue.duty(pwmval)

print("Connecting to MQTT server... ", end="")
client = MQTTClient(MQTT_CLIENT_ID, MQTT_BROKER, user=MQTT_USER, password=MQTT_PASSWORD)
client.set_callback(sub_cb)     #定义好client参数之后，就需要在connect之前
client.connect()
print("Connected!")
client.subscribe(TOPIC1)    #connect之后就需要马上订阅主题，才能收到mqtt服务器送过来的信息
client.subscribe(TOPIC2) 
print("Connected!")