import machine
import time
import dht
import network
import urequests
from machine import Pin, I2C, ADC
from i2c_lcd import I2cLcd

# Pin definitions
MQPin = ADC(Pin(34))
RED_LED = Pin(5, Pin.OUT)
GREEN_LED = Pin(4, Pin.OUT)
BLUE_LED = Pin(2, Pin.OUT)
sensor = dht.DHT22(Pin(14))

# I2C LCD setup
I2C_ADDR = 0x27
I2C_NUM_ROWS = 2
I2C_NUM_COLS = 16

i2c = I2C(0, scl=Pin(22), sda=Pin(21), freq=100000)
lcd = None

# WiFi credentials
ssid = "Wokwi-GUEST"
password = ""

# Firebase configurations
API_KEY = "4uPkFkREEXvmzXo6B4xoBUdPEm2gAFvWQdMfSFyA"
DATABASE_URL = "https://gas-leak-esp32-default-rtdb.asia-southeast1.firebasedatabase.app/"

def scan_i2c_devices(i2c):
    devices = i2c.scan()
    if len(devices) == 0:
        print("No I2C devices found!")
    else:
        print("I2C devices found:", devices)
    return devices

def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    wlan.connect(ssid, password)
    
    lcd.clear()
    lcd.putstr("Connecting to\n{}".format(ssid))
    print("Connecting to WiFi...")

    while not wlan.isconnected():
        time.sleep(0.5)
        lcd.putstr(".")
        print(".")
    
    lcd.clear()
    ip = wlan.ifconfig()[0]
    lcd.putstr("WiFi Connected\nIP: {}".format(ip))
    print("WiFi Connected, IP: {}".format(ip))
    time.sleep(2)
    lcd.clear()

def send_to_firebase(data):
    url = "{}/Values.json?auth={}".format(DATABASE_URL, API_KEY)
    headers = {"Content-Type": "application/json"}
    try:
        response = urequests.put(url, json=data, headers=headers)
        if response.status_code == 200:
            print("Data sent to Firebase successfully")
        else:
            print("Failed to send data to Firebase")
        response.close()
    except Exception as e:
        print("Error: ", e)

def setup():
    global lcd
    devices = scan_i2c_devices(i2c)
    if I2C_ADDR not in devices:
        print("LCD not found at address", I2C_ADDR)
        return
    
    lcd = I2cLcd(i2c, I2C_ADDR, I2C_NUM_ROWS, I2C_NUM_COLS)
    lcd.putstr("  GAS LEAKAGE\n   DETECTOR")
    print("GAS LEAKAGE DETECTOR")
    time.sleep(2)
    lcd.clear()
    
    connect_wifi()

def loop():
    while True:
        gas_value = MQPin.read()
        print("Gas Value: {}".format(gas_value))

        try:
            sensor.measure()
            temperature = sensor.temperature()
            humidity = sensor.humidity()
            print("Temperature: {}°C".format(temperature))
            print("Humidity: {}%".format(humidity))
        except Exception as e:
            print("Failed to read from DHT sensor:", e)
            temperature = None
            humidity = None
        
        if gas_value > 1000:
            GREEN_LED.off()
            BLUE_LED.on()
            for _ in range(5):
                RED_LED.on()
                time.sleep(0.2)
                RED_LED.off()
                time.sleep(0.2)
            lcd.clear()
            lcd.putstr("  GAS DETECTED\n   WARNING!!!")
            print("GAS DETECTED WARNING!!!")
            time.sleep(1)
        else:
            RED_LED.off()
            GREEN_LED.on()
            BLUE_LED.off()
            lcd.clear()
            lcd.putstr("     NO GAS\n    DETECTED")
            print("NO GAS DETECTED")
            time.sleep(1)
        
        if temperature is not None and humidity is not None:
            lcd.clear()
            print("Temperature: {}°C".format(temperature))
            print("Humidity: {}%".format(humidity))            
            time.sleep(2)
        
        data = {
            "gas_value": gas_value,
            "temperature": temperature,
            "humidity": humidity,
        }
        send_to_firebase(data)
        time.sleep(2)

setup()
loop()