from machine import I2C, Pin
from time import sleep

# Setup I2C
i2c = I2C(0, scl=Pin(1), sda=Pin(0), freq=400000)
I2C_ADDR = 0x27  # Adjust if needed

# LCD constants
LCD_WIDTH = 20
LCD_LINE_1 = 0x80
LCD_LINE_2 = 0xC0
LCD_LINE_3 = 0x94
LCD_LINE_4 = 0xD4
LCD_BACKLIGHT = 0x08
ENABLE = 0b00000100

# Send byte to LCD
def lcd_strobe(data):
    i2c.writeto(I2C_ADDR, bytes([data | ENABLE | LCD_BACKLIGHT]))
    sleep(0.0005)
    i2c.writeto(I2C_ADDR, bytes([(data & ~ENABLE) | LCD_BACKLIGHT]))
    sleep(0.0001)

def lcd_write_four_bits(data):
    i2c.writeto(I2C_ADDR, bytes([data | LCD_BACKLIGHT]))
    lcd_strobe(data)

def lcd_write_cmd(cmd):
    lcd_write_four_bits(cmd & 0xF0)
    lcd_write_four_bits((cmd << 4) & 0xF0)

def lcd_write_char(char):
    lcd_write_four_bits((char & 0xF0) | 0x01)
    lcd_write_four_bits(((char << 4) & 0xF0) | 0x01)

def lcd_init():
    sleep(0.02)
    lcd_write_four_bits(0x30)
    sleep(0.005)
    lcd_write_four_bits(0x30)
    sleep(0.001)
    lcd_write_four_bits(0x30)
    lcd_write_four_bits(0x20)

    lcd_write_cmd(0x28)  # 4-bit, 2 lines, 5x8 font
    lcd_write_cmd(0x0C)  # Display on, cursor off, blink off
    lcd_write_cmd(0x06)  # Entry mode
    lcd_write_cmd(0x01)  # Clear display
    sleep(0.002)

def lcd_clear():
    lcd_write_cmd(0x01)
    sleep(0.002)

def lcd_set_cursor(line):
    lcd_write_cmd(line)

def lcd_puts(message, line):
    lcd_set_cursor(line)
    msg = str(message)  # Safely ensure it's a string
    padded = msg + ' ' * (LCD_WIDTH - len(msg))  # Manual right-padding
    for char in padded[:LCD_WIDTH]:
        lcd_write_char(ord(char))

# Timer Function
def format_time(seconds):
    mins = seconds // 60
    secs = seconds % 60
    return "{:02}:{:02}".format(mins, secs)

def timer(seconds):
    lcd_clear()
    lcd_puts("Countdown Timer", LCD_LINE_1)
    for t in range(seconds, -1, -1):
        lcd_puts("Time Left: " + format_time(t), LCD_LINE_2)
        sleep(1)
    lcd_puts("   Time's up!    ", LCD_LINE_3)

# === Main ===
lcd_init()
timer(120)  # Countdown from 2 minutes