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

button = Pin(23,Pin.IN,Pin.PULL_UP)
debounce_delay = 50
button_presses = 0
MAX_BUTTON_PRESS = 5

# I2C Pin setup for ESP32
i2c = I2C(0,scl=Pin(22), sda=Pin(21), freq=10000) 

# LCD setup for ESP32

I2C_ADDR = i2c.scan()[0] 
totalRows = 2  
totalColumns = 16 
lcd = I2cLcd(i2c, I2C_ADDR, totalRows, totalColumns) 



# Ultrasonic Sensor setup
ultra = HCSR04(25,26)


#Button Setup

def handle_button_press_tmr(tmr):
    global button_presses
    tmr.deinit()
    if button.value() == 0:
        button_presses = (button_presses + 1)
    if button_presses == MAX_BUTTON_PRESS:
        button_presses = 1


def handle_button_press_intr(pin):
    tmr = Timer(-1)
    tmr.init(mode=Timer.ONE_SHOT, period=debounce_delay, callback=handle_button_press_tmr)




def measure_distance():
    # Return the distance in cm
    return ultra.distance_cm()

def display_distance(distance):
    # Display distance on LCD
    lcd.clear()
    lcd.putstr("Distance:{_distance:.3f}".format(_distance=distance))

displayed_string = ''
def display_string(to_display):
    global displayed_string
    if to_display == displayed_string:
        return
    lcd.clear()
    lcd.putstr(to_display)
    displayed_string = to_display



def main():
    button.irq(handler = handle_button_press_intr,trigger = Pin.IRQ_FALLING | Pin.IRQ_RISING)
    global button_presses
    while True:
        # Keep the main functionality running
        if button_presses == 0:
            display_string('Press Button to Start')
        elif button_presses == 1:
            display_distance(measure_distance())
        elif button_presses == 2:
            display_string('DECI Students')
            time.sleep(1)
            display_string('Embedded Systems')
        elif button_presses == 3:
            distance = measure_distance()
            if distance < 50:
                display_string('Too Close')
            elif 50 < distance < 100 :
                display_string('Keep Distance')
            elif distance > 100:
                display_string('Safe')
        elif button_presses == 4:
            display_string(f'LCD Address {I2C_ADDR}')

        time.sleep(1)

if __name__ == "__main__":
    main()