from machine import Pin, PWM, ADC
import utime

# ---------------------------------------
# PINOUT SESUAI PERINTAH:
# LDR: VCC -> 3V3 Pico
# LDR: GND -> GND.4 Pico
# LDR: A0  -> GP28
# LED: GP6 -> Resistor -> LED -> GND
# Buzzer: GP15 -> Positif, GND6 -> Negatif
# ---------------------------------------

# Inisialisasi sensor dan aktuator
ldr = ADC(28)                  # LDR analog di GP28
led = Pin(6, Pin.OUT)          # LED di GP6
buzzer = PWM(Pin(15))          # Buzzer di GP15
buzzer.freq(1000)
buzzer.duty_u16(0)             # Buzzer dimatikan di awal

# Fungsi konversi ADC ke lux
def adc_to_lux(adc_value):
    return (adc_value / 65535) * 900 + 10  # estimasi dari 10-1000 lux

# Kalibrasi nilai lux normal selama 2 detik
print("Kalibrasi lux normal...")
samples = []
start_time = utime.ticks_ms()
while utime.ticks_diff(utime.ticks_ms(), start_time) < 2000:
    samples.append(adc_to_lux(ldr.read_u16()))
    utime.sleep(0.05)

lux_normal = sum(samples) / len(samples)
print(f"Lux Normal: {lux_normal:.2f} Lux")

# Variabel status alarm
alarm_active = False
led_state = False
blink_start_time = 0
last_blink_toggle = 0

# Loop utama
while True:
    analog_value = ldr.read_u16()
    lux = adc_to_lux(analog_value)
    print(f"Lux Sekarang: {lux:.2f} Lux")

    if not alarm_active and lux > lux_normal + 250:
        print(">>> Cahaya terlalu terang - Alarm Aktif <<<")
        alarm_active = True
        blink_start_time = utime.ticks_ms()
        last_blink_toggle = blink_start_time
        buzzer.duty_u16(int(0.45 * 65535))  # Duty cycle 45%

    if alarm_active:
        now = utime.ticks_ms()

        # Kedip LED setiap 300ms
        if utime.ticks_diff(now, last_blink_toggle) >= 300:
            led_state = not led_state
            led.value(led_state)
            last_blink_toggle = now

        # Setelah 4 detik, matikan alarm
        if utime.ticks_diff(now, blink_start_time) >= 4000:
            alarm_active = False
            led.value(0)
            buzzer.duty_u16(0)
            print(">>> Alarm Selesai <<<")

    utime.sleep(0.1)