# main.py – DHT22 Weather Station with OLED Display on Raspberry Pi Pico W

from machine import Pin, I2C
import time
import dht
from ssd1306 import SSD1306_I2C

# --- Pin Configuration ---
DHT_PIN = 15
sensor = dht.DHT22(Pin(DHT_PIN))

# --- I2C Configuration for OLED (change pins if needed) ---
i2c = I2C(1, scl=Pin(27), sda=Pin(26), freq=400000)
oled = SSD1306_I2C(128, 64, i2c)

# --- Function to Read DHT22 Safely ---
def read_dht22():
    for _ in range(3):
        try:
            sensor.measure()
            t = sensor.temperature()
            h = sensor.humidity()
            if -40 <= t <= 80 and 0 <= h <= 100:
                return t, h
        except OSError:
            pass
        time.sleep(1)
    return None, None

# --- Function to Display Data on OLED ---
def display_data(temp, hum):
    oled.fill(0)  # Clear screen
    oled.text(" WEATHER STATION ", 0, 0)
    oled.text("----------------", 0, 10)
    oled.text("Temp: {:.1f} C".format(temp), 0, 25)
    oled.text("Hum : {:.1f} %".format(hum), 0, 40)

    # Simple status messages
    if temp > 35:
        oled.text("HOT!", 90, 25)
    elif temp < 18:
        oled.text("COLD", 90, 25)

    oled.show()

# --- Main Loop ---
while True:
    temp, hum = read_dht22()
    if temp is not None and hum is not None:
        print("Temperature: {:.1f}°C  Humidity: {:.1f}%".format(temp, hum))
        display_data(temp, hum)
    else:
        print("⚠️ Sensor reading failed!")
        oled.fill(0)
        oled.text("Sensor Error!", 10, 25)
        oled.show()
    time.sleep(3)