import machine, time, dht, network, socket

# ---------------- WiFi / ThingSpeak config ----------------
WIFI_SSID = "Wokwi-GUEST"        # Wokwi's simulated open network - gives real internet access
WIFI_PASSWORD = ""
THINGSPEAK_API_KEY = "G5DILGAIGY3MY6Q1"   # <-- paste your channel's Write API Key here
THINGSPEAK_HOST = "api.thingspeak.com"
UPDATE_INTERVAL_MS = 20000       # free ThingSpeak tier allows 1 update / 15s - 20s to be safe

# ---------------- Sensor & actuator setup ----------------
soil_sensor = machine.ADC(machine.Pin(34))
soil_sensor.atten(machine.ADC.ATTN_11DB)

temp_sensor = dht.DHT22(machine.Pin(4))

pump_relay = machine.Pin(26, machine.Pin.OUT)
pump_led   = machine.Pin(27, machine.Pin.OUT)

MOISTURE_THRESHOLD = 40
MOISTURE_DRY_RAW   = 4095
MOISTURE_WET_RAW   = 1200


def connect_wifi():
    wlan = network.WLAN(network.STA_IF)
    wlan.active(True)
    if not wlan.isconnected():
        print("Connecting to WiFi...")
        wlan.connect(WIFI_SSID, WIFI_PASSWORD)
        while not wlan.isconnected():
            time.sleep(0.5)
    print("WiFi connected, IP:", wlan.ifconfig()[0])


def send_to_thingspeak(moisture, temperature, pump_on):
    try:
        path = "/update?api_key={}&field1={}&field2={}&field3={}".format(
            THINGSPEAK_API_KEY, moisture, temperature, 1 if pump_on else 0
        )
        addr = socket.getaddrinfo(THINGSPEAK_HOST, 80)[0][-1]
        s = socket.socket()
        s.settimeout(5)
        s.connect(addr)
        s.send(bytes("GET {} HTTP/1.0\r\nHost: {}\r\n\r\n".format(path, THINGSPEAK_HOST), "utf8"))
        response = s.recv(200)
        s.close()
        print("ThingSpeak response:", response)
    except Exception as e:
        print("ThingSpeak upload failed:", e)


def read_moisture_percent():
    raw = soil_sensor.read()
    pct = (MOISTURE_DRY_RAW - raw) * 100 / (MOISTURE_DRY_RAW - MOISTURE_WET_RAW)
    return max(0, min(100, pct))


def read_temperature():
    try:
        temp_sensor.measure()
        return temp_sensor.temperature()
    except Exception:
        return None


connect_wifi()

pump_on = False
last_upload = time.ticks_ms()

while True:
    moisture = read_moisture_percent()
    temperature = read_temperature()

    if moisture < MOISTURE_THRESHOLD and not pump_on:
        pump_relay.value(1)
        pump_led.value(1)
        pump_on = True
    elif moisture >= MOISTURE_THRESHOLD and pump_on:
        pump_relay.value(0)
        pump_led.value(0)
        pump_on = False

    print("Soil Moisture: {:.1f}% | Temp: {} C | Pump: {}".format(
        moisture, temperature, "ON" if pump_on else "OFF"))

    if time.ticks_diff(time.ticks_ms(), last_upload) >= UPDATE_INTERVAL_MS:
        send_to_thingspeak(moisture, temperature if temperature is not None else 0, pump_on)
        last_upload = time.ticks_ms()

    time.sleep(2)