#define BUTTON_PIN 2
#define BUZZER_PIN 8
const int pingPin = 13;
int inPin = 12;
int RGBPin[] = { 11, 10, 9 }; 
 
void setup() {
  Serial.begin(9600);
  pinMode(BUTTON_PIN, INPUT_PULLUP); // ใช้ pull-up ภายใน
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(pingPin, OUTPUT);
  pinMode(RGBPin[0], OUTPUT);
  pinMode(RGBPin[1], OUTPUT);
  pinMode(RGBPin[2], OUTPUT);
}

void SetRGB(int r, int g, int b) {
  analogWrite(RGBPin[0], r);
  analogWrite(RGBPin[1], g);
  analogWrite(RGBPin[2], b);
}

 
void loop(){
  long duration, cm;

  digitalWrite(pingPin, LOW);
  delayMicroseconds(2);
  digitalWrite(pingPin, HIGH);
  delayMicroseconds(5);
  digitalWrite(pingPin, LOW);
  pinMode(inPin, INPUT);
  duration = pulseIn(inPin, HIGH);
  cm = microsecondsToCentimeters(duration);

  if (digitalRead(BUTTON_PIN) == HIGH) {
    SetRGB(255, 0, 0); // ปุ่มกดอยู่ เปิดไฟแดง
    cm = 400;
  }

  if(cm<400){
    digitalWrite(BUZZER_PIN, HIGH); // เปิดเสียง
    SetRGB(255, 0, 0); // Red
  }else{
    digitalWrite(BUZZER_PIN, LOW); // ปิดเสียง
    SetRGB(0, 255, 0); // Green
  }


  Serial.print(cm);
  Serial.print("cm");
  Serial.println();
  delay(100);
}
 
long microsecondsToCentimeters(long microseconds){
  // The speed of sound is 340 m/s or 29 microseconds per centimeter.
  // The ping travels out and back, so to find the distance of the
  // object we take half of the distance travelled.
  return microseconds / 29 / 2;
}