from machine import Pin, ADC
import time

# ---------------- PIN CONFIG ----------------
LDR_PIN = 34
PIR_PIN = 27
TOUCH_PIN = 14
RELAY_PIN = 26

# ---------------- SETTINGS ----------------
DARK_THRESHOLD = 1500     # Adjust after testing
INTERACTION_TIME = 30    # seconds

# ---------------- HARDWARE INIT ----------------
pir = Pin(PIR_PIN, Pin.IN)
touch = Pin(TOUCH_PIN, Pin.IN)
relay = Pin(RELAY_PIN, Pin.OUT)
relay.value(0)

ldr = ADC(Pin(LDR_PIN))
ldr.atten(ADC.ATTN_11DB)
ldr.width(ADC.WIDTH_12BIT)

# ---------------- STATE VARIABLES ----------------
system_active = False
lamp_on = False
pir_start_time = 0

print("Smart Study Table – Smart Lamp Module Started")

# ---------------- FUNCTIONS ----------------
def lamp_on_fn():
    global lamp_on
    relay.value(1)
    lamp_on = True
    print("Lamp ON (Dark detected)")

def lamp_off_fn():
    global lamp_on
    relay.value(0)
    lamp_on = False
    print("Lamp OFF")

# ---------------- MAIN LOOP ----------------
while True:
    pir_state = pir.value()
    touch_state = touch.value()
    ldr_value = ldr.read()
    is_dark = ldr_value < DARK_THRESHOLD
    current_time = time.time()

    # ---- PIR ACTIVATES SYSTEM ----
    if pir_state == 1 and not system_active:
        system_active = True
        pir_start_time = current_time
        print("PIR detected → System ON (30s window started)")

    # ---- SYSTEM ACTIVE WINDOW ----
    if system_active:
        elapsed = current_time - pir_start_time

        # ---- TOUCH PRESSED WITHIN 30s ----
        if touch_state == 1 and elapsed <= INTERACTION_TIME:
            if is_dark:
                lamp_on_fn()
            else:
                print("Enough light → System OFF")
                lamp_off_fn()

            system_active = False
            time.sleep(0.5)  # debounce

        # ---- TIMEOUT (NO TOUCH) ----
        elif elapsed > INTERACTION_TIME:
            print("No interaction → System OFF after 30s")
            lamp_off_fn()
            system_active = False

    # ---- PIR LOST → TURN OFF LAMP ----
    if pir_state == 0 and lamp_on:
        print("No motion → Lamp OFF")
        lamp_off_fn()

    # ---- DEBUG (optional) ----
    print("PIR:", pir_state,
          "TOUCH:", touch_state,
          "LDR:", ldr_value,
          "SYSTEM:", system_active)

    time.sleep(0.2)