int greenLED = 0;        // Pin para el LED verde
int yellowLED = 2;       // Pin para el LED amarillo
int redLED = 3;          // Pin para el LED rojo
int pedestrianButton = 4;// Pin para el botón peatonal
int pedestrianLED = 1;   // Pin para el LED de solicitud de cruce peatonal

int buttonState = 0;     // Variable para almacenar el estado del botón
bool pedestrianRequested = false;
unsigned long buttonPressTime = 0;

void setup() {
  pinMode(greenLED, OUTPUT);
  pinMode(yellowLED, OUTPUT);
  pinMode(redLED, OUTPUT);
  pinMode(pedestrianLED, OUTPUT);
  pinMode(pedestrianButton, INPUT_PULLUP);
  
  digitalWrite(greenLED, LOW);
  digitalWrite(yellowLED, LOW);
  digitalWrite(redLED, LOW);
  digitalWrite(pedestrianLED, LOW);

  Serial.begin(9600);  
}

void loop() {
  buttonState = digitalRead(pedestrianButton);

 
  if (buttonState == LOW && !pedestrianRequested) {
    Serial.println("Botón peatonal presionado");
    pedestrianRequested = true;
    digitalWrite(pedestrianLED, HIGH); 
    buttonPressTime = millis();       
  }

  
  if (pedestrianRequested && millis() - buttonPressTime >= 2000) {
    changeToRed();                    
    pedestrianRequested = false;      
    digitalWrite(pedestrianLED, LOW);  
  } else if (!pedestrianRequested) {
    normalSequence();                 
  }
}

void normalSequence() {
  Serial.println("Semáforo verde encendido");
  digitalWrite(greenLED, HIGH);       
  delay(10000);                      
  
  Serial.println("Semáforo verde apagado, amarillo parpadeando");
  digitalWrite(greenLED, LOW);        
  for (int i = 0; i < 3; i++) {
    digitalWrite(yellowLED, HIGH);     
    delay(500);                       
    digitalWrite(yellowLED, LOW);     
    delay(500);                        
  }

  changeToRed();
}

void changeToRed() {
  Serial.println("Semáforo rojo encendido");
  digitalWrite(redLED, HIGH);          
  delay(10000);                       
  Serial.println("Semáforo rojo apagado");
  digitalWrite(redLED, LOW);           
}