#define BLYNK_TEMPLATE_ID "TMPL3rrBuhmdn"
#define BLYNK_TEMPLATE_NAME "traffic"
#define BLYNK_AUTH_TOKEN "FR81K_0yh9nH8mjmc439peDkOwBa8NkE"

#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

char auth[] = "FR81K_0yh9nH8mjmc439peDkOwBa8NkE"; // Blynk Auth Token
char ssid[] = "Wokwi-GUEST"; // WiFi SSID
char pass[] = ""; // WiFi Password

#define TRIG_PIN 5
#define ECHO_PIN 18
#define RED_LED_PIN 16
#define YELLOW_LED_PIN 17
#define GREEN_LED_PIN 4

#define RED_LED_VPIN V2
#define YELLOW_LED_VPIN V3
#define GREEN_LED_VPIN V4
#define PEDESTRIAN_BUTTON_PIN 19 // Pedestrian crossing button pin

void setup() {
  Serial.begin(115200);
  Blynk.begin(auth, ssid, pass);

  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(RED_LED_PIN, OUTPUT);
  pinMode(YELLOW_LED_PIN, OUTPUT);
  pinMode(GREEN_LED_PIN, OUTPUT);
  pinMode(PEDESTRIAN_BUTTON_PIN, INPUT_PULLUP); // Enable internal pull-up resistor for button pin
}

void loop() {
  Blynk.run();
  manageTraffic();
}

void manageTraffic() {
  long duration, distance;

  // Trigger the ultrasonic sensor to send a pulse
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  // Measure the pulse duration
  duration = pulseIn(ECHO_PIN, HIGH);

  // Calculate the distance (in cm) based on the duration
  distance = (duration / 2) / 29.1;

  // Send the distance to Blynk
  Blynk.virtualWrite(V1, distance);

  // Check if pedestrian button is pressed
  bool pedestrianRequest = digitalRead(PEDESTRIAN_BUTTON_PIN) == LOW;

  // Control traffic lights based on the measured distance and pedestrian request
  if (pedestrianRequest || distance < 10) {
    // Pedestrian request or heavy traffic: Red light on
    digitalWrite(RED_LED_PIN, HIGH);
    digitalWrite(YELLOW_LED_PIN, LOW);
    digitalWrite(GREEN_LED_PIN, LOW);
    Blynk.virtualWrite(RED_LED_VPIN, 1);
    Blynk.virtualWrite(YELLOW_LED_VPIN, 0);
    Blynk.virtualWrite(GREEN_LED_VPIN, 0);
  } else if (distance < 25) {
    // Moderate traffic: Yellow light on
    digitalWrite(RED_LED_PIN, LOW);
    digitalWrite(YELLOW_LED_PIN, HIGH);
    digitalWrite(GREEN_LED_PIN, LOW);
    Blynk.virtualWrite(RED_LED_VPIN, 0);
    Blynk.virtualWrite(YELLOW_LED_VPIN, 1);
    Blynk.virtualWrite(GREEN_LED_VPIN, 0);
  } else {
    // Light traffic: Green light on
    digitalWrite(RED_LED_PIN, LOW);
    digitalWrite(YELLOW_LED_PIN, LOW);
    digitalWrite(GREEN_LED_PIN, HIGH);
    Blynk.virtualWrite(RED_LED_VPIN, 0);
    Blynk.virtualWrite(YELLOW_LED_VPIN, 0);
    Blynk.virtualWrite(GREEN_LED_VPIN, 1);
  }
}