# Imports
from machine import Pin, ADC, SoftI2C
from ssd1306 import SSD1306_I2C
from time import sleep

# Cliente mqtt y wifi
import network
from umqtt.simple import MQTTClient

# Cliente MQTT Constantes   
MQTT_BROKER = 'broker.hivemq.com'
MQTT_USER = ''
MQTT_PASSWORD = ''
MQTT_PORT = 1883
MQTT_CLIENT_ID = ''
MQTT_TOPIC = 'utng/jamb/gas'

# Método para conectarnos a Wifi
def wifi_connect():
    print('Conectado...', end = '')
    sta_if = network.WLAN(network.STA_IF)
    sta_if.active(True)
    sta_if.connect('Wokwi-GUEST', '')
    while not sta_if.isconnected():
        print('.', end = '')
        sleep(0.3)
    print('Conectada')

# Método para suscribir a un topico
def subscribe():
    client = MQTTClient(MQTT_CLIENT_ID,
                        MQTT_BROKER,
                        port = MQTT_PORT,
                        user = MQTT_USER,
                        password = MQTT_PASSWORD,
                        keepalive = 0)
    client.connect()
    print('[OK]')
    client.subscribe(MQTT_TOPIC)
    print("Conectado a %s, en el topico %s", MQTT_BROKER, MQTT_TOPIC)
    return client

def publish(sensor_value):
    client = MQTTClient(MQTT_CLIENT_ID,
                        MQTT_BROKER,
                        port = MQTT_PORT,
                        user = MQTT_USER,
                        password = MQTT_PASSWORD,
                        keepalive = 0)
    client.connect()
    print('[OK]')
    client.publish(MQTT_TOPIC, str(sensor_value))
    print("Se publicó el valor {}, en el topico {}".format(str(sensor_value), MQTT_TOPIC))

# Asignación de PIN en ESP32
i2c = SoftI2C(scl = Pin(22), sda = Pin(21))

# Variables para el oled
oled_width = 128
oled_height = 64
oled = SSD1306_I2C(oled_width, oled_height, i2c)

# Variables para los leds y el sensor
led_verde = Pin(12, Pin.OUT)
led_rojo = Pin(13, Pin.OUT)
sensor = ADC(Pin(32))

# Ajustar la resolución y el voltaje
sensor.width(ADC.WIDTH_10BIT) # Regular la presición del sensor
sensor.atten(ADC.ATTN_11DB) # Trabajando con 3.3V

# Intentando conectarnos a wifi
wifi_connect()


# Ciclo infinito
while True:
    # Lee el valor del sensor
    lectura = sensor.read()

    # Publicamos el valor
    publish(lectura)

    # Limpia la pantalla
    oled.clear()

    if lectura > 200:
        led_rojo.value(1)
        oled.text('Alerta CO High', 0, 30)
        led_verde.value(0)
    else:
        led_verde.value(1)
        oled.text('CO Normal', 0, 30)
        led_rojo.value(0)
    oled.show()
    sleep(10)
    oled.hw_scroll_h()