import RPi.GPIO as GPIO
import time
from pad4pi import rpi_gpio
from Adafruit_CharLCD import Adafruit_CharLCD
from pyfingerprint.pyfingerprint import PyFingerprint

# Pin Definitions
RELAY_PIN = 17
BUZZER_PIN = 18

# Setup GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(RELAY_PIN, GPIO.OUT)
GPIO.setup(BUZZER_PIN, GPIO.OUT)

# Setup LCD
lcd = Adafruit_CharLCD(2, 3, 4, 5, 6, 7, 16, 2, 0, 1, 2, 3)
lcd.clear()

# Setup Keypad
KEYPAD = [
    [1, 2, 3, 'A'],
    [4, 5, 6, 'B'],
    [7, 8, 9, 'C'],
    ['*', 0, '#', 'D']
]

ROW_PINS = [12, 16, 20, 21]
COL_PINS = [6, 13, 19, 26]

factory = rpi_gpio.KeypadFactory()
keypad = factory.create_keypad(keypad=KEYPAD, row_pins=ROW_PINS, col_pins=COL_PINS)

# Pre-defined correct PIN
CORRECT_PIN = '1234'

# Setup Fingerprint Sensor
try:
    fingerprint_sensor = PyFingerprint('/dev/ttyUSB0', 57600, 0xFFFFFFFF, 0x00000000)
    if not fingerprint_sensor.verifyPassword():
        raise ValueError('The given fingerprint sensor password is wrong!')
except Exception as e:
    print('Fingerprint sensor initialization failed!')
    print('Exception message: ' + str(e))
    exit(1)

# Function to unlock the door
def unlock_door():
    GPIO.output(RELAY_PIN, GPIO.HIGH)
    time.sleep(5)  # Keep the door unlocked for 5 seconds
    GPIO.output(RELAY_PIN, GPIO.LOW)

# Function to trigger buzzer alarm
def trigger_alarm():
    GPIO.output(BUZZER_PIN, GPIO.HIGH)
    time.sleep(5)
    GPIO.output(BUZZER_PIN, GPIO.LOW)

# Keypad event handler
def keypad_handler(key):
    global input_pin, incorrect_attempts
    if key == '#':
        if input_pin == CORRECT_PIN:
            lcd.clear()
            lcd.message('Enter Fingerprint')
            if validate_fingerprint():
                lcd.clear()
                lcd.message('Access Granted')
                unlock_door()
                incorrect_attempts = 0
            else:
                lcd.clear()
                lcd.message('Access Denied')
                incorrect_attempts += 1
                check_incorrect_attempts()
        else:
            lcd.clear()
            lcd.message('Invalid PIN')
            incorrect_attempts += 1
            check_incorrect_attempts()
        input_pin = ''
    elif key == '*':
        input_pin = ''
        lcd.clear()
    else:
        input_pin += str(key)
        lcd.message(str(key))

# Fingerprint validation
def validate_fingerprint():
    try:
        lcd.clear()
        lcd.message('Waiting for finger...')
        while not fingerprint_sensor.readImage():
            pass

        fingerprint_sensor.convertImage(0x01)
        result = fingerprint_sensor.searchTemplate()
        position_number = result[0]

        if position_number >= 0:
            return True
        else:
            return False
    except Exception as e:
        print('Fingerprint validation failed!')
        print('Exception message: ' + str(e))
        return False

# Check incorrect attempts and trigger alarm if necessary
def check_incorrect_attempts():
    if incorrect_attempts >= 3:
        trigger_alarm()
        incorrect_attempts = 0

# Main program
input_pin = ''
incorrect_attempts = 0
keypad.registerKeyPressHandler(keypad_handler)

try:
    lcd.message('Enter PIN:')
    while True:
        time.sleep(0.1)
except KeyboardInterrupt:
    print("Exiting...")

finally:
    GPIO.cleanup()
    keypad.cleanup()
    lcd.clear()