// Define the Blynk template ID and name
#define BLYNK_TEMPLATE_ID "TMPL5pa9-i7IL"
#define BLYNK_TEMPLATE_NAME "IOT Smart Trafficking"

// Define the pin numbers for various components
#define TRIG_PIN 5 // Ultrasonic sensor trigger pin
#define ECHO_PIN 18 // Ultrasonic sensor echo pin
#define GREEN_LED 22 // Green LED pin
#define RED_LED 19 // Red LED pin
#define YELLOW_LED 21 // Yellow LED pin
#define BUZZER_PIN 15 // Buzzer pin
#define DHT_PIN 4 // Pin where the DHT22 sensor is connected
#define DHTTYPE DHT22 // Type of DHT sensor used (DHT22)

// Include necessary libraries
#include <DHT.h>
#include <WiFi.h>
#include <BlynkSimpleEsp32.h>

// Define network credentials
char ssid[] = "Wokwi-GUEST"; // WiFi SSID
char pass[] = ""; // WiFi password

// Define Blynk authentication token
char auth[] = "8HX4xf2X5PEolN8OWfkYQG7E5h0Vbthl"; // Blynk auth token

// Initialize the DHT sensor
DHT dht(DHT_PIN, DHTTYPE);

void setup() {
  Serial.begin(115200); // Start serial communication at 115200 baud rate

  // Set the pin modes for the ultrasonic sensor and LEDs
  pinMode(TRIG_PIN, OUTPUT); // Set trigger pin as output
  pinMode(ECHO_PIN, INPUT); // Set echo pin as input
  pinMode(GREEN_LED, OUTPUT); // Set green LED pin as output
  pinMode(RED_LED, OUTPUT); // Set red LED pin as output
  pinMode(YELLOW_LED, OUTPUT); // Set yellow LED pin as output
  pinMode(BUZZER_PIN, OUTPUT); // Set buzzer pin as output

  dht.begin(); // Initialize the DHT sensor
  Blynk.begin(auth, ssid, pass); // Initialize Blynk with authentication and WiFi credentials
}

void loop() {
  long duration, distance; // Variables for ultrasonic sensor reading
  String status = "STOP"; // Default status

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

  // Read the echo pin and calculate the distance
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = (duration / 2) / 29.1;  // Convert duration to distance in cm

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Reset the buzzer
  noTone(BUZZER_PIN);

  // Set LED color and buzzer based on distance
  if (distance < 50) {
    setColor(0, 255, 0);  // Green
    tone(BUZZER_PIN, 3000);  // Activate buzzer at 3000 Hz
    status = "GO"; // Update status to "GO"
  } else if (distance >= 50 && distance <= 200) {
    setColor(0, 0, 255);  // Yellow
    tone(BUZZER_PIN, 2000);  // Activate buzzer at 2000 Hz
    status = "WAIT"; // Update status to "WAIT"
  } else if (distance > 200) {
    setColor(255, 0, 0);  // Red
    tone(BUZZER_PIN, 100);  // Activate buzzer at 100 Hz
    status = "STOP"; // Update status to "STOP"
  }

  // Read temperature and humidity from the DHT sensor
  float h = dht.readHumidity();
  float t = dht.readTemperature(); // Read temperature as Celsius (default)
  if (isnan(h) || isnan(t)) {
    Serial.println("Failed to read from DHT sensor!");
    return; // Exit if reading fails
  }

  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.println(" *C");

  // Send temperature, humidity, and status to Blynk
  Blynk.virtualWrite(V1, t);  // Write temperature to virtual pin V1
  Blynk.virtualWrite(V2, h);  // Write humidity to virtual pin V2
  Blynk.virtualWrite(V3, status); // Write status to virtual pin V3
  Blynk.run(); // Run Blynk

  delay(1000);  // Wait for 1 second before next reading
}

// Function to set the color of the RGB LED
void setColor(int red, int green, int blue) {
  analogWrite(RED_LED, red); // Set red LED brightness
  analogWrite(GREEN_LED, green); // Set green LED brightness
  analogWrite(YELLOW_LED, blue); // Set yellow LED brightness
  delay(1000); // Delay for 1 second to allow color change to take effect
}