from machine import Pin  
from gpio_lcd import GpioLcd
import time
import utime

tank_height = 150 #give the height in centimeter that the ultrasonic detects the height of tank in empty stage

trigger = Pin(15,Pin.OUT)#Give the Pin number that which pin You used
echo = Pin(14,Pin.IN)#Give the Pin number that which pin You used


buzzer = Pin(2,Pin.OUT)
relay = Pin(7,Pin.OUT)

def lcd():
    display = GpioLcd(rs_pin = Pin(8),
                  enable_pin = Pin(9),
                  d4_pin = Pin(10),
                  d5_pin = Pin(11),
                  d6_pin = Pin(12),
                  d7_pin = Pin(13))
    distance_in_percentage = (Distance() * (100/tank_height))
    display.move_to(0,0)
    display.putstr("TANK WATER LVL")
    
    display.move_to(4,1)
    display.putstr(str(int((100+10)-distance_in_percentage))+" %")
    print(str(int((100+10)-distance_in_percentage))+" %")
    

def Distance():
    trigger.low()
    utime.sleep_us(2)
    trigger.high()
    utime.sleep_us(5)
    trigger.low()
    while echo.value()==0:
        signal_transmitted_time = utime.ticks_us()
    while echo.value()==1:
        signal_received_time = utime.ticks_us()
    overall_time = signal_received_time - signal_transmitted_time
    distance = (0.0344 * overall_time) / 2
    
    return distance

while True:
    
    
    
    
    if Distance() <= 15:
        relay.off()
        lcd()
        if Distance() <=10:
            
            for i in range(20):
                lcd()
                buzzer.on()
                utime.sleep(0.5)
                buzzer.off()
                utime.sleep(0.5)
                if Distance() > 10:
                    break
                
        else:
            lcd()
            buzzer.off()
            
    elif Distance() >= (tank_height-10):
        lcd()
        relay.on()
        if Distance() >= (tank_height-5):
            for i in range(10):
                lcd()
                buzzer.on()
                utime.sleep(0.5)
                buzzer.off()
                utime.sleep(0.5)
                if Distance() < (tank_height-5):
                    break
                
        else:
            lcd()
            buzzer.off()
    else:
        lcd()
        utime.sleep(0.5)
        continue