from machine import Pin, I2C
import utime
import ssd1306

trig= Pin(0, Pin.OUT, value=0 )
echo= Pin(1, Pin.IN)
RelayIn = Pin(2, Pin.OUT, value=0)
RelayOut= Pin(3,Pin.OUT, value=0)
btn= Pin(4, Pin.IN, Pin.PULL_UP)
i2c = I2C(0, scl=Pin(5), sda=Pin(6))
oled = ssd1306.SSD1306_I2C(128, 64, i2c)

D =320 
h= 0 
def ultrason():
    trig.off()
    trig.on()
    utime.sleep_us(10)
    trig.off()
    while echo.value() == 0:
        Toff = utime.ticks_us()
    while echo.value() == 1:
        Ton = utime.ticks_us()
    t= (Ton - Toff) / 2
    distance = int (t * 0.0343)
    
    h=320 - distance
    hPercent = int(h*(100/300))
    if 210<=h<=270:
        RelayIn.on()
        RelayOut.on()
    elif h>270:
        RelayIn.off()
        RelayOut.on()
    else:
        RelayIn.on()
        RelayOut.off()
        
def display_water_level():
    oled.fill(0)
    oled.text(f"Water Level: {hPercent}%", 0,0)
    oled.show()

while True :
    if btn.value()==0 : #Button is pressed(assuming active low)
        ultrason()
        display_water_level()
        utime.sleep_ms(50)
    else:
        oled.fill(0)
        oled.text("Press button to measure", 0,0)
        oled.show()