import time                    # Import time library
import board                   # Import Raspberry Pi Pico pins
import digitalio               # Import digital I/O library
import pwmio                   # Import PWM library
import busio                   # Import I2C library
import lcd                     # Import LCD library
import i2c_pcf8574_interface   # Import LCD I2C interface

# LCD SETUP

i2c = busio.I2C(scl=board.GP27, sda=board.GP26)   # Create I2C

i2c_interface = i2c_pcf8574_interface.I2CPCF8574Interface(i2c, 0x27)   # LCD address

display = lcd.LCD(i2c_interface, num_rows=2, num_cols=16)   # Create LCD

display.set_backlight(True)   # LCD backlight ON

display.set_display_enabled(True)   # Enable LCD

# 7 SEGMENT SETUP

bcd_ones = [board.GP6, board.GP7, board.GP8, board.GP9]   # 7-segment pins

class CD4511:

    def __init__(self, pins):

        self.bcd = []

        for pin in pins:

            p = digitalio.DigitalInOut(pin)

            p.direction = digitalio.Direction.OUTPUT

            self.bcd.append(p)

    def display(self, num):

        num = max(0, min(9, num))

        for i in range(4):

            self.bcd[i].value = (num >> i) & 1

ones_disp = CD4511(bcd_ones)

# KEYPAD SETUP

row_pins = [board.GP10, board.GP11, board.GP12, board.GP13]

col_pins = [board.GP14, board.GP15, board.GP16, board.GP17]

rows = [digitalio.DigitalInOut(pin) for pin in row_pins]

cols = [digitalio.DigitalInOut(pin) for pin in col_pins]

for row in rows:

    row.direction = digitalio.Direction.OUTPUT

    row.value = True

for col in cols:

    col.direction = digitalio.Direction.INPUT

    col.pull = digitalio.Pull.UP

keymap = [

    ["1", "2", "3", "A"],

    ["4", "5", "6", "B"],

    ["7", "8", "9", "C"],

    ["*", "0", "#", "D"]

]

# PARKING LEDS

slot1_led = digitalio.DigitalInOut(board.GP2)

slot1_led.direction = digitalio.Direction.OUTPUT

slot2_led = digitalio.DigitalInOut(board.GP3)

slot2_led.direction = digitalio.Direction.OUTPUT

slot3_led = digitalio.DigitalInOut(board.GP4)

slot3_led.direction = digitalio.Direction.OUTPUT

# STATUS LEDS

green_led = digitalio.DigitalInOut(board.GP18)

green_led.direction = digitalio.Direction.OUTPUT

red_led = digitalio.DigitalInOut(board.GP19)

red_led.direction = digitalio.Direction.OUTPUT

# BUZZER

buzzer = digitalio.DigitalInOut(board.GP20)

buzzer.direction = digitalio.Direction.OUTPUT

# BUTTONS

exit_button = digitalio.DigitalInOut(board.GP22)

exit_button.direction = digitalio.Direction.INPUT

exit_button.pull = digitalio.Pull.UP

alarm_button = digitalio.DigitalInOut(board.GP28)

alarm_button.direction = digitalio.Direction.INPUT

alarm_button.pull = digitalio.Pull.UP

# SERVOS

entry_servo_pwm = pwmio.PWMOut(board.GP21, frequency=50)

exit_servo_pwm = pwmio.PWMOut(board.GP0, frequency=50)

def set_servo(servo, angle):

    duty = int(1638 + (angle / 180) * (8192 - 1638))

    servo.duty_cycle = duty

# VARIABLES

password = "0571"

user_input = ""

attempts = 3

system_open = False

TOTAL_SLOTS = 3

occupied_slots = 0

parking_slots = [0, 0, 0]

# DISPLAY FUNCTION

def update_display():

    available = TOTAL_SLOTS - occupied_slots

    ones_disp.display(available)

# LCD FUNCTION

def show_slots():

    line = ""

    for i in range(3):

        if parking_slots[i] == 0:

            line += "S" + str(i + 1) + ":F "

        else:

            line += "S" + str(i + 1) + ":O "

    display.clear()

    display.set_cursor_pos(0, 0)

    display.print("SMART PARKING")

    display.set_cursor_pos(1, 0)

    display.print(line[:16])

# MESSAGE FUNCTION

def show_message(line1, line2):

    display.clear()

    display.set_cursor_pos(0, 0)

    display.print(line1)

    display.set_cursor_pos(1, 0)

    display.print(line2)

# LED FUNCTION

def update_leds():

    slot1_led.value = parking_slots[0]

    slot2_led.value = parking_slots[1]

    slot3_led.value = parking_slots[2]

    if occupied_slots < TOTAL_SLOTS:

        green_led.value = True

        red_led.value = False

    else:

        green_led.value = False

        red_led.value = True

# KEYPAD FUNCTION

def read_key():

    for r, row in enumerate(rows):

        row.value = False

        for c, col in enumerate(cols):

            if not col.value:

                time.sleep(0.2)

                while not col.value:
                    pass

                row.value = True

                return keymap[r][c]

        row.value = True

    return None

# GATE FUNCTION

def open_gate(servo):

    buzzer.value = True

    time.sleep(0.2)

    buzzer.value = False

    set_servo(servo, 90)

    time.sleep(3)

    set_servo(servo, 0)

# STARTUP

set_servo(entry_servo_pwm, 0)

set_servo(exit_servo_pwm, 0)

update_display()

update_leds()

show_message("PARKING LOCKED", "ENTER PASSWORD")

# MAIN LOOP

while True:

    update_display()

    update_leds()

    key = read_key()

    # PASSWORD SYSTEM

    if system_open == False:

        if key:

            if key == "#":

                if user_input == password:

                    system_open = True

                    attempts = 3

                    user_input = ""

                    show_message("ACCESS GRANTED", "PARKING OPEN")

                    time.sleep(2)

                    update_leds()

                    show_slots()

                else:

                    attempts -= 1

                    show_message("WRONG PASSWORD", "TRY AGAIN")

                    red_led.value = True

                    buzzer.value = True

                    time.sleep(1)

                    red_led.value = False

                    buzzer.value = False

                    if attempts == 0:

                        display.clear()

                        display.set_cursor_pos(0, 0)

                        display.print("SYSTEM LOCKED")

                        display.set_cursor_pos(1, 0)

                        display.print("WAIT 10 SEC")

                        for seconds in range(10, -1, -1):

                            ones_disp.display(seconds)

                            red_led.value = True

                            green_led.value = True

                            slot1_led.value = True

                            slot2_led.value = True

                            slot3_led.value = True

                            buzzer.value = True

                            time.sleep(0.5)

                            red_led.value = False

                            green_led.value = False

                            slot1_led.value = False

                            slot2_led.value = False

                            slot3_led.value = False

                            buzzer.value = False

                            time.sleep(0.5)

                        attempts = 3

                    user_input = ""

                    show_message("PARKING LOCKED", "ENTER PASSWORD")

            elif key == "*":

                user_input = user_input[:-1]

            elif len(user_input) < 4:

                user_input += key

            if system_open == False:

                display.set_cursor_pos(1, 0)

                display.print("                ")

                display.set_cursor_pos(1, 0)

                display.print("*" * len(user_input))

    # PARKING SYSTEM

    else:

        # EXIT BUTTON

        if not exit_button.value:

            show_message("CAR EXITED", "EXIT OPENING")

            open_gate(exit_servo_pwm)

            occupied_slots = max(0, occupied_slots - 1)

            for i in range(3):

                if parking_slots[i] == 1:

                    parking_slots[i] = 0

                    break

            update_leds()

            show_slots()

            time.sleep(1)

        # ALARM BUTTON

        if not alarm_button.value:

            display.clear()

            display.set_cursor_pos(0, 0)

            display.print("EMERGENCY!")

            display.set_cursor_pos(1, 0)

            display.print("ALARM ACTIVE")

            for i in range(15):

                red_led.value = True

                green_led.value = True

                slot1_led.value = True

                slot2_led.value = True

                slot3_led.value = True

                buzzer.value = True

                time.sleep(0.15)

                red_led.value = False

                green_led.value = False

                slot1_led.value = False

                slot2_led.value = False

                slot3_led.value = False

                buzzer.value = False

                time.sleep(0.15)

            update_leds()

            show_slots()

        # PARKING SLOT SELECTION

        if key in ["1", "2", "3"]:

            slot = int(key) - 1

            if parking_slots[slot] == 0:

                show_message("SLOT " + key + " FREE", "ENTRY OPENING")

                open_gate(entry_servo_pwm)

                parking_slots[slot] = 1

                occupied_slots += 1

            else:

                show_message("SLOT " + key + " BUSY", "CHOOSE ANOTHER")

            update_leds()

            show_slots()

    time.sleep(0.1)