#include <Servo.h>

#define TRIG 9
#define ECHO 10
#define SERVO 6
#define BUZZER 8
#define LED 13
#define PIR 7

Servo myServo;

void setup() {
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(LED, OUTPUT);
  pinMode(PIR, INPUT);
  
  myServo.attach(SERVO);
  Serial.begin(9600);
}

void loop() {
  // Measure distance
  digitalWrite(TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG, LOW);

  long duration = pulseIn(ECHO, HIGH);
  int distance = duration * 0.034 / 2;

  Serial.println(distance);

  // PIR detects hand → Open lid
  if (digitalRead(PIR) == HIGH) {
    myServo.write(90);  // Open lid
    delay(2000);
    myServo.write(0);   // Close lid
  }

  // If trash full
  if (distance < 10) {
    digitalWrite(BUZZER, HIGH);
    digitalWrite(LED, HIGH);
  } else {
    digitalWrite(BUZZER, LOW);
    digitalWrite(LED, LOW);
  }

  delay(500);
}