"""
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 machine
from machine import Timer
import ssd1306

# 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('hejiajie', 10, 10)
oled.text('2306022227', 10, 30)
for i in range(128):
    oled.pixel(i,50,1)
oled.show()


# MQTT Server Parameters
MQTT_CLIENT_ID = "hejiajie2306022227"
MQTT_BROKER    = "broker.emqx.io"
MQTT_USER      = ""
MQTT_PASSWORD  = ""
MQTT_TOPIC     = "wokwi-weather-hejiajie2306022227"
TOPIC1 = b"ledctl2306022227"  #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"pwmled2306022227"
TOPIC3 = b"ledstatus2306022227"

sensor = dht.DHT22(Pin(15))
led_blue = machine.PWM(machine.Pin(2), freq=1000)  # 设置 GPIO2 为输出
led_blue.duty(1023)

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!")

def sub_cb(topic, msg):   #定义收到mqtt主题信息之后的回调函数
    global pwm_old, pwmval
    if topic == TOPIC1:
        print((topic, msg))
        if msg == b"on":
            pwmval = 0
            led_blue.duty(pwmval)

        elif msg == b"off":
            led_blue.duty(1023)
            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之前设定回调函数。
client.connect()

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!")

prev_weather = ""

def sample_weather(v):
  global prev_weather
  print("Measuring weather conditions... ", end="")
  sensor.measure() 
  message = ujson.dumps({
    "temp": sensor.temperature(),
    "humidity": sensor.humidity(),
  })
  if message != prev_weather:
    print("Updated!")
    print("Reporting to MQTT topic {}: {}".format(MQTT_TOPIC, message))
    oled.fill(0)
    oled.text('temp:{} dc'.format(sensor.temperature()),0,20)
    oled.text('humidity:{} %'.format(sensor.humidity()),0,40)
    oled.show()
    client.publish(MQTT_TOPIC, message)
    prev_weather = message
  else:
    print("No change")
tim = Timer(-1)
tim.init(period=5000, mode=Timer.PERIODIC, callback=sample_weather)

while True:
    client.wait_msg()
    time.sleep(1)