from machine import Pin, I2C, ADC, PWM
import ssd1306
import dht
import time

# === I2C setup for OLED ===
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
oled = ssd1306.SSD1306_I2C(128, 64, i2c)

# === Sensors setup ===
dht_sensor = dht.DHT22(Pin(15))
mq2 = ADC(Pin(34)); mq2.atten(ADC.ATTN_11DB)
ldr = ADC(Pin(35)); ldr.atten(ADC.ATTN_11DB)

# === Outputs ===
buzzer = PWM(Pin(27))
buzzer.freq(1000)
buzzer.duty(0)

led_sprinkler = Pin(26, Pin.OUT)
led_fan = Pin(25, Pin.OUT)
led_light = Pin(33, Pin.OUT)
relay = Pin(32, Pin.OUT)

# === RGB LED Pins ===
red = Pin(14, Pin.OUT)
green = Pin(12, Pin.OUT)
blue = Pin(13, Pin.OUT)

# === Button (Active Low) ===
button = Pin(4, Pin.IN, Pin.PULL_UP)

# === Thresholds ===
SMOKE_THRESHOLD = 80.0
TEMP_THRESHOLD = 20.0
LIGHT_THRESHOLD = 75.0  # Percentage (0 = very bright, 100 = very dark)

# === State Variables ===
system_on = False
last_button_state = 1
debounce_time = 0

# === Helper functions ===
def get_smoke_percent(value):
    return min(max((value / 4095) * 100, 0), 100)

def get_light_percent(value):
    return min(max((1 - value / 4095) * 100, 0), 100)

def set_rgb_color(r, g, b):
    red.value(r)
    green.value(g)
    blue.value(b)

def shutdown_all():
    buzzer.duty(0)
    led_sprinkler.value(0)
    led_fan.value(0)
    led_light.value(0)
    relay.value(0)
    set_rgb_color(0, 0, 0)
    oled.fill(0)
    oled.text("System OFF", 20, 28)
    oled.show()

# === Main loop ===
while True:
    current_time = time.ticks_ms()
    current_button = button.value()

    # Toggle detection with debounce
    if current_button == 0 and last_button_state == 1 and (current_time - debounce_time) > 300:
        system_on = not system_on
        debounce_time = current_time
    last_button_state = current_button

    if system_on:
        try:
            dht_sensor.measure()
            temp = dht_sensor.temperature()
            humidity = dht_sensor.humidity()
            gas_value = mq2.read()
            smoke_percent = get_smoke_percent(gas_value)
            ldr_value = ldr.read()
            light_percent = get_light_percent(ldr_value)

            # Temp LED
            led_fan.value(1 if temp >= TEMP_THRESHOLD and smoke_percent < SMOKE_THRESHOLD else 0)

            # RGB LED color based on temperature
            if temp <= 20:
                set_rgb_color(0, 0, 1)  # Blue
            elif 20 <= temp <= 38:
                set_rgb_color(0, 1, 0)  # Green
            elif 38 <= temp <= 80:
                set_rgb_color(1, 0, 0)  # Red
            else:
                set_rgb_color(0, 0, 0)

            # Light LED only ON when it's truly dark
            led_light.value(0 if light_percent >= LIGHT_THRESHOLD else 1)

            # === OLED Update (no flickering) ===
            oled.fill(0)
            oled.text("Temp: {:.1f} C".format(temp), 0, 0)
            oled.text("Hum: {:.1f}%".format(humidity), 0, 12)
            oled.text("Smoke: {:.1f}%".format(smoke_percent), 0, 24)
            oled.text("Light: {:.1f}%".format(light_percent), 0, 36)

            # Smoke alert logic
            if smoke_percent >= SMOKE_THRESHOLD:
                led_sprinkler.value(1)
                buzzer.duty(512)
                relay.value(1)
                oled.text("SMOKE ALERT!", 0, 48)
                oled.text("FIRE WARNING!", 0, 56)
            else:
                led_sprinkler.value(0)
                buzzer.duty(0)
                relay.value(0)

            oled.show()

        except Exception:
            pass  # Silently ignore sensor read errors
    else:
        shutdown_all()

    time.sleep(0.1)