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

# ---------------- WIFI ----------------
ssid = "Wokwi-GUEST"
password = ""

wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.connect(ssid, password)

while not wifi.isconnected():
    print("Connecting to WiFi...")
    time.sleep(1)

print("Connected:", wifi.ifconfig())

# ---------------- THINGSPEAK ----------------
api_key = "YOUR_API_KEY"

# ---------------- SENSORS ----------------
sensor = dht.DHT22(Pin(15))
pir = Pin(3, Pin.IN)
ldr = ADC(26)
mq2 = ADC(27)

# ---------------- BUFFER ----------------
buffer = []   # stores failed data

# ---------------- SEND FUNCTION ----------------
def send_data(data):
    try:
        url = (
            "http://api.thingspeak.com/update?api_key={}"
            "&field1={}&field2={}&field3={}&field4={}&field5={}"
        ).format(api_key, *data)

        r = urequests.get(url)
        print("Sent:", data, "| Response:", r.text)
        r.close()
        return True

    except Exception as e:
        print("Send Failed:", e)
        return False

# ---------------- MAIN LOOP ----------------
while True:
    try:
        # Read sensors
        sensor.measure()
        temp = sensor.temperature()
        hum = sensor.humidity()
        motion = pir.value()
        light = ldr.read_u16()
        gas = mq2.read_u16()

        current_data = (temp, hum, gas, light, motion)

        print("\nCurrent:", current_data)

        # 🔥 Step 1: Send buffered data first
        if buffer:
            print("Retrying buffered data...")
            for old_data in buffer[:]:
                if send_data(old_data):
                    buffer.remove(old_data)

        # 🔥 Step 2: Send current data
        if not send_data(current_data):
            print("Adding to buffer...")
            buffer.append(current_data)

        print("Buffer size:", len(buffer))

    except Exception as e:
        print("Error:", e)

    time.sleep(15)