#define BLYNK_PRINT Serial
#define BLYNK_TEMPLATE_ID "TMPL3D5v3eeYP"
#define BLYNK_TEMPLATE_NAME "Smart cattle monitoring system"
#define BLYNK_AUTH_TOKEN "e5DWuf-79V3zPXgHdsemiFr9QdCvQ-YW"
#include <Arduino.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <WiFi.h>
#include <WiFiClient.h>
#include<BlynkSimpleEsp32.h>


char auth[] = BLYNK_AUTH_TOKEN;
char ssid[] = "Wokwi-GUEST";
char pass[] = "";

LiquidCrystal_I2C lcd(0x27, 20, 4);

#define LED_PIN 5
#define TRIG_PIN 19
#define ECHO_PIN 18

#define BLINK_INTERVAL 500

int cattleCount = 0;
unsigned long previousMillis = 0;
bool ledState = false;
long distanceCm = 0;
int blinkCount = 0;
bool countingStopped = false;

void connectToWiFi() {
  Serial.print("Connecting to Wi-Fi");
  WiFi.begin(ssid, pass);
  int retries = 0;
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
    retries++;
    if (retries > 20) {
      Serial.println(" Failed to connect. Restarting...");
      ESP.restart();
    }
  }
  Serial.println(" Connected to Wi-Fi");
}

void setup() {
  
  Serial.begin(115200);
  Blynk.begin(auth, ssid, pass);
  lcd.init();
  lcd.backlight();
  lcd.clear();

  pinMode(LED_PIN, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  connectToWiFi();

  lcd.setCursor(0, 0);
  lcd.print("Smart Cattle");
  lcd.setCursor(0, 1);
  lcd.print("Monitoring");
  delay(2000);
  lcd.clear();
}

void measureDistance() {
  
  long duration;
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distanceCm = duration * 0.034 / 2;
}

void updateDisplay() {
  
  lcd.setCursor(0, 0);
  lcd.print("Distance: ");
  lcd.print(distanceCm);
  lcd.print(" cm");
  lcd.setCursor(0, 2);
  lcd.print("Cattle Count:");
  lcd.print(cattleCount);
  delay(1000);
  
}

void blinkLED() {
  unsigned long currentMillis = millis();
  if (!countingStopped) {
    if (currentMillis - previousMillis >= BLINK_INTERVAL) {
      previousMillis = currentMillis;
      ledState = !ledState;
      digitalWrite(LED_PIN, ledState ? HIGH : LOW);
    
      
    }
  } 
  
  else if (countingStopped && blinkCount < 4) {
    if (currentMillis - previousMillis >= BLINK_INTERVAL) {
      previousMillis = currentMillis;
      ledState = !ledState;
      digitalWrite(LED_PIN, ledState ? HIGH : LOW);
      blinkCount++;
    }
  } else {
    digitalWrite(LED_PIN, LOW);
    ledState = false;
  }
}

void loop() {
   
  measureDistance();

  
  if (distanceCm < 400 && cattleCount < 25) {
    cattleCount++;
    countingStopped = false;
    blinkCount = 0;
  } else if (cattleCount == 25) {
    countingStopped = true;
  }

  updateDisplay();
  Blynk.virtualWrite(V0, cattleCount);
  Blynk.virtualWrite(V2, distanceCm);

  blinkLED();
  
  Serial.print("Distance: ");
  Serial.print(distanceCm);
  Serial.println(" cm");
  delay(1000);
  Blynk.run();
}