import machine
import network
import time
import urequests
import ujson
import utime

# WiFi credentials
WIFI_SSID = "Wokwi-GUEST"
WIFI_PASSWORD = ""

# ThingSpeak credentials
THINGSPEAK_API_KEY = "V1DLGOM7Z9FE7W9M"
THINGSPEAK_URL = "https://api.thingspeak.com/update"


# DHT22 (AM2302) sensor on GPIO 4
LDR_SENSOR_PIN = machine.ADC(1)

# Function to read analog pin
def read_ldr():
    ldr_data = LDR_SENSOR_PIN.read_u16()
    return ldr_data

def adc_to_lux():
    GAMMA = 0.7
    RL = 50
    voltage = ldr / 65535 * 5
    resistance = 2000 * voltage / (1 - voltage / 5)
    lux_value = (RL * 1e3 * pow(10, GAMMA) / resistance) ** (1 / GAMMA) 
    return lux_value

# Function to send data to ThingSpeak
def send_data_to_thingspeak(ldr, lux):
  data = {
    "api_key": THINGSPEAK_API_KEY,
    "field1": ldr,
    "field2": lux,
  }
  response = urequests.post(THINGSPEAK_URL, data=ujson.dumps(data),headers={"Content-Type":"application/json"})
  response.close()

# Initialize the Wifi connection
wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.connect(WIFI_SSID,WIFI_PASSWORD)

# wait for the Wi-Fi connection to establish
while not wifi.isconnected():
  time.sleep(1)

print("Connected to Wi-Fi")

if __name__ == "__main__":
  try:
    while True:
      ldr = read_ldr()
      print(f"ADC:{ldr}")

      lux = adc_to_lux()
      print(f"Lux Value: {lux}")

      send_data_to_thingspeak(ldr, lux)
      print("Data sent to ThingSpeak")

      time.sleep(30)
  except KeyboardInterrupt:
    pass