import time
import dht
import urequests
import network
from machine import Pin

# Define GPIO pins
TRIG_PIN = 2
ECHO_PIN = 3
BUZZER_PIN = 4
DHT_PIN = 5
LED_PIN = 6

# Define your Wi-Fi SSID and password
WIFI_SSID = "Galaxy A14"
WIFI_PASSWORD = "124567891"

# Define your ThingSpeak API Key and Channel ID
THING_SPEAK_API_KEY = "GYZTW85RNGCZSLE9"
THING_SPEAK_CHANNEL_ID = "2316433"

# Function to establish a Wi-Fi connection
def connect_wifi(ssid, password):
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    if not wlan.isconnected():
        print("Connecting to Wi-Fi...")
        wlan.connect(ssid, password)
        while not wlan.isconnected():
            pass
    print("Connected to Wi-Fi:", wlan.ifconfig())

def distance_measurement():
    # Trigger ultrasonic sensor
    trigger = Pin(TRIG_PIN, Pin.OUT)
    trigger.on()
    time.sleep_us(10)
    trigger.off()

    # Wait for echo to be HIGH (start time)
    echo = Pin(ECHO_PIN, Pin.IN)
    while not echo.value():
        pass
    pulse_start = time.ticks_us()

    # Wait for echo to be LOW (end time)
    while echo.value():
        pass
    pulse_end = time.ticks_us()

    # Calculate distance
    pulse_duration = time.ticks_diff(pulse_end, pulse_start)
    distance = pulse_duration / 58  # Speed of sound (343 m/s) divided by 2

    return distance

def read_dht_sensor():
    dht_sensor = dht.DHT22(Pin(DHT_PIN, Pin.IN))
    dht_sensor.measure()
    return dht_sensor.temperature(), dht_sensor.humidity()

buzz_start_time = None  # To track when the buzzer started

# Connect to Wi-Fi
connect_wifi(WIFI_SSID, WIFI_PASSWORD)

while True:
    dist = distance_measurement()
    temp, humidity = read_dht_sensor()
    status = "No Flooding Detected"

    if dist < 50:
        # Turn on the buzzer and LED
        Pin(BUZZER_PIN, Pin.OUT).on()
        Pin(LED_PIN, Pin.OUT).on()
        status = "Flooding Detected"
        buzz_start_time = time.ticks_ms()
    elif buzz_start_time is not None and time.ticks_diff(time.ticks_ms(), buzz_start_time) >= 60000:  # 1 minute
        # Turn off the buzzer and LED after 1 minute
        Pin(BUZZER_PIN, Pin.OUT).off()
        Pin(LED_PIN, Pin.OUT).off()

    print("Distance: {:.2f} cm".format(dist))
    print("Temperature: {:.2f}°C, Humidity: {:.2f}%".format(temp, humidity))
    print("Status:", status)

    # Send data to ThingSpeak
    try:
        data = {
            "api_key": THING_SPEAK_API_KEY,
            "field1": dist,
            "field2": temp,
            "field3": humidity,
        }
        response = urequests.post("https://api.thingspeak.com/update.json", json=data)
        response.close()
    except Exception as e:
        print("Error sending data to ThingSpeak:", e)

    time.sleep(2)