from machine import Pin, I2C
import time
from hcsr04 import HCSR04
from lcd_api import LcdApi
from i2c_lcd import I2cLcd

i2c = I2C(0, scl=Pin(22), sda=Pin(21), freq=400000)


i2c_addr = i2c.scan()[0]  
lcd = I2cLcd(i2c, i2c_addr, 2, 16)  
sensor = HCSR04(trigger_pin=5, echo_pin=18, echo_timeout_us=10000)


button_pin = Pin(19, Pin.IN, Pin.PULL_UP)

press_count = 1  
last_press_time = 0 

def measure_distance():
    try:
        distance = sensor.distance_cm()
        return distance
    except Exception as e:
        return None


def display_distance(distance):
    lcd.clear()
    if distance is not None:
        lcd.putstr("Distance:\n{:.1f} cm".format(distance))
    else:
        lcd.putstr("Sensor Error")


def button_handler(pin):
    global press_count, last_press_time
    current_time = time.ticks_ms()
    if time.ticks_diff(current_time, last_press_time) > 500:  
        press_count += 1
        if press_count > 5:
            press_count = 1
        last_press_time = current_time


button_pin.irq(trigger=Pin.IRQ_FALLING, handler=button_handler)


def main():
    global press_count
    while True:
        if button_pin.value() == 0:  
            distance = measure_distance()
            display_distance(distance)
            time.sleep(1)  

        
        lcd.clear()
        if press_count == 1:
            distance = measure_distance()
            display_distance(distance)
            time.sleep(1)
            
        elif press_count == 2:
            lcd.putstr("DECI students")
            time.sleep(1)
            lcd.clear()
            lcd.putstr("Embedded systems")
            time.sleep(1)
            
        elif press_count == 3:
            distance = measure_distance()
            lcd.clear()
            if distance is not None:
                if distance < 50:
                    lcd.putstr("Too close")
                elif distance < 100:
                    lcd.putstr("Keep distance")
                else:
                    lcd.putstr("Safe")
            else:
                lcd.putstr("Sensor Error")
            time.sleep(1)
            
        elif press_count == 4:
            lcd.putstr("I2C Addr:\n{}".format(hex(i2c_addr)))
            time.sleep(2)
            
        elif press_count == 5:
            press_count = 1
        
        else:
            press_count = 1

if __name__ == "__main__":
    main()