#include <LiquidCrystal_I2C.h>

const int trigger = 32;
const int echo = 33;
const int pump = 22;
const int buzzer = 25;

long duration;
float distance;
int waterlevel;
int pumpstate = LOW;
bool buzzFlag = false;
float levellow = 8.5; // cm
float levelhigh = 2.5; // cm

LiquidCrystal_I2C lcd(0x27, 16, 2);

void pumpAutomate() {
    digitalWrite(trigger, LOW);
    delayMicroseconds(2);
    digitalWrite(trigger, HIGH);
    delayMicroseconds(10);
    digitalWrite(trigger, HIGH);

    duration = pulseIn(echo, HIGH);
    distance = (duration / 2.0) / 29.1; // Calculate distance in cm

    // Map the distance to a percentage (inverse mapping)
    waterlevel = map(distance * 100, levelhigh * 100, levellow * 100, 100, 0);
    waterlevel = constrain(waterlevel, 0, 100);

    if (waterlevel <= 10) {
        pumpstate = HIGH;
        if (!buzzFlag) {
            digitalWrite(buzzer, HIGH);
            delay(1000);
            digitalWrite(buzzer, LOW);
            buzzFlag = true;
        }
    } else if (waterlevel >= 90) {
        pumpstate = LOW;
    } else {
        buzzFlag = false;
    }
digitalWrite(pump, pumpstate);
    lcd.setCursor(0, 0);
    lcd.print("WATER LEVEL=");
    lcd.print(waterlevel);
    lcd.print("%");
    lcd.setCursor(0, 1);
    lcd.print("WATER PUMP=");
    lcd.print(pumpstate ? "HIGH" : "LOW ");
}

void setup() {
    pinMode(trigger, OUTPUT);
    pinMode(echo, INPUT);
    pinMode(pump, OUTPUT);

    lcd.init();
    lcd.backlight();
    lcd.setCursor(0, 0);
    lcd.print("Initialization...");
}

void loop() {
    pumpAutomate();
}