import board
import digitalio
import time
import busio
import pwmio

# LCD libraries
import lcd
import i2c_pcf8574_interface

# === LCD SETUP ===
i2c = busio.I2C(scl=board.GP5, sda=board.GP4)
address = 0x27
i2c_interface = i2c_pcf8574_interface.I2CPCF8574Interface(i2c, address)
display = lcd.LCD(i2c_interface, num_rows=2, num_cols=16)
display.set_backlight(True)
display.set_display_enabled(True)

# === PIR SENSOR ===
pir = digitalio.DigitalInOut(board.GP16)
pir.direction = digitalio.Direction.INPUT

# === LED SETUP ===
led = digitalio.DigitalInOut(board.GP7)
led.direction = digitalio.Direction.OUTPUT

# === BUZZER SETUP (initial dummy assignment) ===
buzzer = pwmio.PWMOut(board.GP15, duty_cycle=0, frequency=1000)

# === SYSTEM VARIABLES ===
ALARM_DURATION = 5  # seconds

# === TRIGGER ALARM FUNCTION ===
def trigger_alarm(duration):
    global buzzer  # Allow modifying the global buzzer object

    start_time = time.monotonic()

    while (time.monotonic() - start_time) < duration:
        print("!! Motion Detected !!")

        led.value = True
        display.clear()
        display.print("ALERT!\nMotion Detected")

        # Siren effect: alternate between 1000 Hz and 2000 Hz
        for _ in range(5):
            buzzer.deinit()
            buzzer = pwmio.PWMOut(board.GP15, frequency=1000, duty_cycle=32768)
            time.sleep(0.2)
            buzzer.deinit()
            buzzer = pwmio.PWMOut(board.GP15, frequency=2000, duty_cycle=32768)
            time.sleep(0.2)

        # Pause LED and buzzer
        led.value = False
        buzzer.deinit()
        time.sleep(0.3)

    # Reset after alarm
    led.value = False
    buzzer.deinit()
    display.clear()
    display.print("System Ready")

# === MAIN LOOP ===
display.print("System Ready")
while True:
    if pir.value:
        print("PIR: Motion Detected")
        trigger_alarm(ALARM_DURATION)
    else:
        print("PIR: No Motion")
    time.sleep(0.1)