# Project objectives: 
#   Read temperature and humidity values from the DHT22 sensor
#   Display the sensor readings in the console
#
# Hardware connections used:
#   DHT22 VCC Pin to 3.3V
#   DHT22 SDA Pin to GPIO Pin 15
#   10k ohm pull-up resistor from DHT22 SDA Pin to 3.3V
#   DHT22 GND Pin to GND
#
# Programmer: Adrian Josele G. Quional

# modules
from machine import Pin , PWM , I2C
from time import sleep
from dht import DHT22   # if the sensor is DHT11, import DHT11 instead of DHT22
from pico_i2c_lcd import I2cLcd

# creating a DHT object
# change DHT22 to DHT11 if DHT11 is used
dht = DHT22(Pin(19)) 
i2c = I2C(0, sda=Pin(0), scl=Pin(1), freq=400000)

I2C_ADDR = i2c.scan()[0]
lcd = I2cLcd(i2c, I2C_ADDR, 2, 16)

def buzzerFunc():
  buzzer = PWM(Pin(15))
  buzzer.freq(500)
  buzzer.duty_u16(1000)
  sleep(1)
  buzzer.duty_u16(0)

def display_lcd(text):
    lcd.clear()
    lcd.putstr(text)

# continuously get sensor readings while the board has power
while True:
    # getting sensor readings
    dht.measure()
    temp = dht.temperature()
    hum = dht.humidity()

    # displaying values to the console
    print(f"Temperature: {temp}°C   Humidity: {hum}% ")
    lcd_text = f"Temp: {temp:.1f}°C\nHumidity: {hum:.1f}%"
    display_lcd(lcd_text)
    
    # format method or string concatenation may also be used
    #print("Temperature: {}°C   Humidity: {:.0f}% ".format(temp, hum))
    #print("Temperature: " + str(temp) + "°C" + "   Humidity: " + str(hum) + "%")
    
    # delay of 2 secs because DHT22 takes a reading once every 2 secs
    sleep(2)

    if(temp > 20 and hum > 30):
      buzzerFunc()
    else:
      None