const int trigPin = 9;
const int echoPin = 10;
const int ledGreen = 2;
const int ledOrange = 3;
const int ledRed = 4;

unsigned long lastDetectionTime = 0;
unsigned long detectionInterval = 0;
const unsigned long intervalGreen = 60000; 
const unsigned long intervalOrange = 120000; 
const unsigned long intervalRed = 180000; 

void setup() {
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(ledGreen, OUTPUT);
  pinMode(ledOrange, OUTPUT);
  pinMode(ledRed, OUTPUT);

  Serial.begin(9600);
}

void loop() {
  unsigned long currentTime = millis();
  long duration, distance;
  
  // Envoi du signal trigger
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Lecture du signal echo
  duration = pulseIn(echoPin, HIGH);
  distance = (duration / 2) / 29.1;
  
  if (distance < 20) {
    lastDetectionTime = currentTime;
  }
  
  detectionInterval = currentTime - lastDetectionTime;

  // Gestion des LEDs en fonction de l'intervalle
  if (detectionInterval < intervalGreen) {
    digitalWrite(ledGreen, HIGH);
    digitalWrite(ledOrange, LOW);
    digitalWrite(ledRed, LOW);
  } else if (detectionInterval < intervalOrange) {
    digitalWrite(ledGreen, LOW);
    digitalWrite(ledOrange, HIGH);
    digitalWrite(ledRed, LOW);
  } else {
    digitalWrite(ledGreen, LOW);
    digitalWrite(ledOrange, LOW);
    digitalWrite(ledRed, HIGH);
  }
  
  delay(1000); 
}