import machine
import time
import dht
import network


# ==========================================
#STEP 1: HARDWARE PIN ALIGNMENT
#========================================== 
DHT_PIN_NUMBER = 15  # Pin number where your DHT sensor wire is connected
sensor = dht.DHT22(machine.Pin(DHT_PIN_NUMBER)) 

#The magic limit number that triggers our automatic system alerts
TEMPERATURE_THRESHOLD = 30

#========================================= 
#STEP 3: WI-FI NETWORK SETUP
#========================================= 
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD =""

print("--- Connecting to the Smart Grid Network ---")
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(WIFI_SSID, WIFI_PASSWORD)

# Wait until the virtual microchip handshakes with the network
while not wlan.isconnected():
    print(".", end="")
    time.sleep(0.5)
    
print("/n Connected securely to the network!")
print("Device IP Configuration:", wlan.ifconfig()[0])

# Setting up our background stopwatch timer (in milliseconds)
last_sensor_read = time.ticks_ms()

# ==========================================
# STEP 5: THE CONTINUOUS LIVE LOOP
# ==========================================
while True:
    # CRITICAL: This must run constantly to process background heartbeat signals.
    # Never use time.sleep() directly inside this loop, or you will freeze the connection!
    
    
    # Check our stopwatch: Have 2000 milliseconds (2 seconds) passed?
    current_time = time.ticks_ms()
    if time.ticks_diff(current_time, last_sensor_read) >= 2000:
        try:
            # Ask the sensor to check the air temperature
            sensor.measure()
            current_temp = sensor.temperature()
            # Local IF/THEN Logic: Has the temperature crossed our boundary line?
            
            if current_temp > TEMPERATURE_THRESHOLD:
                print("⚠  Alert! Threshold limit crossed!")
            else: print("Live Temperature Reading:", current_temp, "°C")
        except OSError as e:
            print("Error: Sensor reading delayed. Checking circuit pathways...")
        
        # Reset our background stopwatch tracking point for the next 2 seconds
        last_sensor_read = current_time