#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Initialize I2C LCD
LiquidCrystal_I2C lcd(0x27, 16, 2); // Replace 0x27 with your LCD's I2C address

// Ultrasonic sensor pins
const int trigPin = 9;
const int echoPin = 10;

// Buzzer pin
const int buzzerPin = 11;

// Maximum bin height (in cm)
const int binHeight = 300; // Adjust this based on bin size
// Threshold for full bin (in cm)
const int threshold = 50;  // Distance indicating the bin is full

void setup() {
  // Initialize pins
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  
  // Initialize LCD
  lcd.begin(16, 2);
  lcd.backlight();

  //Serial.begin(9600);
}

void loop() {
  // Measure distance
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  long duration = pulseIn(echoPin, HIGH);
  int distance = duration * 0.034 / 2;
  
   //Check for valid distance
  //if (distance <= 0 || distance > binHeight) {
   // return; // Skip this loop if distance is out of range
  //}
  
  // Calculate fullness percentage
  int fullness = 100 - (distance * 100 / binHeight);
  //fullness = constrain(fullness, 0, 100); // Ensure fullness is between 0 and 100
  
  // Display fullness percentage on LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Waste Level:");
  lcd.setCursor(0, 1);
  lcd.print(fullness);
  lcd.print("%");

  // Check if bin is full
  if (distance <= threshold) {
    digitalWrite(buzzerPin, HIGH); // Activate buzzer
    lcd.setCursor(10, 1);
    lcd.print("Full!");
    delay(500); // Slight delay to prevent buzzer from toggling rapidly
  } else {
    digitalWrite(buzzerPin, LOW); // Deactivate buzzer
  }

  delay(1000); // Refresh rate of 1 second
}