import time
import board
import digitalio
import busio
from i2c_lcd import I2cLcd
import builtins

str = builtins.str

# ===== LCD Setup (I2C) =====
i2c = busio.I2C(scl=board.GP1, sda=board.GP16)
lcd = I2cLcd(i2c, 0x27, 2, 16)

# ===== Keypad Setup =====
keymap = [
    ['1', '2', '3'],
    ['4', '5', '6'],
    ['7', '8', '9'],
    ['*', '0', '#']
]
row_pins = [board.GP18, board.GP19, board.GP20, board.GP21]
col_pins = [board.GP22, board.GP26, board.GP27, board.GP28]
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 = False
for col in cols:
    col.direction = digitalio.Direction.INPUT
    col.pull = digitalio.Pull.DOWN

# ===== Buttons =====
submit_button = digitalio.DigitalInOut(board.GP15)
submit_button.direction = digitalio.Direction.INPUT
submit_button.pull = digitalio.Pull.UP

shutdown_button = digitalio.DigitalInOut(board.GP14)
shutdown_button.direction = digitalio.Direction.INPUT
shutdown_button.pull = digitalio.Pull.UP

# ===== LEDs =====
green_led = digitalio.DigitalInOut(board.GP6)
green_led.direction = digitalio.Direction.OUTPUT
green_led.value = False

red_led = digitalio.DigitalInOut(board.GP7)
red_led.direction = digitalio.Direction.OUTPUT
red_led.value = False

shutdown_led = digitalio.DigitalInOut(board.GP17)
shutdown_led.direction = digitalio.Direction.OUTPUT
shutdown_led.value = False

# ===== 7-Segment Setup (A–G) =====
seg_pins = [board.GP2, board.GP3, board.GP4, board.GP5, board.GP8, board.GP9, board.GP10]
segments_gpio = [digitalio.DigitalInOut(pin) for pin in seg_pins]
for seg in segments_gpio:
    seg.direction = digitalio.Direction.OUTPUT
    seg.value = False

dp = digitalio.DigitalInOut(board.GP11)
dp.direction = digitalio.Direction.OUTPUT
dp.value = False

# ===== Segment Display Map =====
segments = {
    '0': [0,0,0,0,0,0,1],
    '1': [1,0,0,1,1,1,1],
    '2': [0,0,1,0,0,1,0],
    '3': [0,0,0,0,1,1,0],
    '4': [1,0,0,1,1,0,0],
    '5': [0,1,0,0,1,0,0],
    '6': [0,1,0,0,0,0,0],
    '7': [0,0,0,1,1,1,1],
    '8': [0,0,0,0,0,0,0],
    '9': [0,0,0,0,1,0,0],
    ' ': [1,1,1,1,1,1,1]
}

def display_digit(digit, dot=False):
    pattern = segments.get(digit, segments[' '])
    for seg, val in zip(segments_gpio, pattern):
        seg.value = val
    dp.value = dot

def clear_digit():
    for seg in segments_gpio:
        seg.value = False
    dp.value = False

# ===== Display Functions =====
def read_keypad():
    for i, row in enumerate(rows):
        row.value = True
        for j, col in enumerate(cols):
            if col.value:
                while col.value:
                    time.sleep(0.01)
                row.value = False
                return keymap[i][j]
        row.value = False
    return None

def display_message(line1, line2=""):
    try:
        lcd.clear()
        lcd.move_to(0, 0)
        lcd.putstr(str(line1)[:16])
        lcd.move_to(0, 1)
        lcd.putstr(str(line2)[:16])
    except Exception as e:
        lcd.clear()
        lcd.move_to(0, 0)
        lcd.putstr("LCD ERROR")
        lcd.move_to(0, 1)
        lcd.putstr(str(e)[:16])

# ===== Countdown Functions =====
def start_countdown():
    global countdown_active, countdown_value, last_countdown_time
    countdown_active = True
    countdown_value = 9
    last_countdown_time = time.monotonic()
    display_digit(str(countdown_value))
    display_message("ACCESS GRANTED", f"Time left: {countdown_value}s")

def update_countdown():
    global countdown_active, countdown_value, last_countdown_time
    now = time.monotonic()
    
    if now - last_countdown_time >= 1:  # 1 second elapsed
        countdown_value -= 1
        last_countdown_time = now
        
        if countdown_value >= 0:
            display_digit(str(countdown_value))
            display_message("ACCESS GRANTED", f"Time left: {countdown_value}s")
        else:
            # Countdown finished
            countdown_active = False
            display_digit(' ')
            display_message("Enter PIN:")
            green_led.value = False

# ===== Constants & Variables =====
SECRET_CODE = "1111"
input_code = ""
last_input_time = time.monotonic()

# Countdown state
countdown_active = False
countdown_value = 9
last_countdown_time = 0

# Shutdown state
system_active = True

# ===== Startup Display =====
display_message("Welcome", "Enter PIN:")
display_digit(' ')

# ===== Main Loop =====
while True:
    now = time.monotonic()

    # Shutdown toggle
    if not shutdown_button.value:
        time.sleep(0.3)  # debounce
        system_active = not system_active
        if not system_active:
            # System off: clear everything
            lcd.clear()
            green_led.value = False
            red_led.value = False
            clear_digit()
            shutdown_led.value = False
        else:
            # System on again
            shutdown_led.value = True
            display_message("Enter PIN:")
            display_digit(' ')
        continue  # skip rest of loop when toggled

    # Skip all functions if system is OFF
    if not system_active:
        time.sleep(0.1)
        continue

    # Handle countdown if active
    if countdown_active:
        update_countdown()
        time.sleep(0.1)  # Shorter sleep during countdown
        continue  # Skip other inputs during countdown

    # Submit PIN
    if not submit_button.value:
        time.sleep(0.2)  # debounce
        if input_code == SECRET_CODE:
            display_message("ACCESS", "GRANTED")
            green_led.value = True
            red_led.value = False
            start_countdown()
        else:
            display_message("ACCESS", "DENIED")
            green_led.value = False
            red_led.value = True
            time.sleep(2)
            display_message("Enter PIN:")
            display_digit(' ')
        input_code = ""
        last_input_time = now

    # Timeout reset (20s)
    if now - last_input_time > 20:
        input_code = ""
        display_message("Timeout", "Enter PIN:")
        display_digit(' ')
        last_input_time = now

    # Keypad input
    key = read_keypad()
    if key:
        last_input_time = now
        if key == "*":
            input_code = input_code[:-1]
        elif len(input_code) < 4:
            input_code += key
        display_message("Enter PIN:", "*" * len(input_code))
        if input_code:
            digit = input_code[-1]
            display_digit(digit, dot=(len(input_code) == 4))
        else:
            display_digit(' ')

    time.sleep(0.1)  # Reduced sleep for better responsiveness