#define BLYNK_TEMPLATE_ID "TMPL3PiOwaDrx"
#define BLYNK_TEMPLATE_NAME "Annal D"
#define BLYNK_AUTH_TOKEN "vS3AtpEVY1no4YBsZwMB5XFRb5hXXxAT"
#define BLYNK_PRINT Serial

#include <WiFi.h>
#include<WiFiClient>
#include <Wire.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_GFX.h>
#include <NewPing.h>
#include <BlynkSimpleEsp32.h>
#include <TinyGPS++.h>

// Blynk Auth Token
char auth[] = "vS3AtpEVY1no4YBsZwMB5XFRb5hXXxAT";

// Your WiFi credentials.
char ssid[] = "Wokwi-Guest";
char pass[] = "";

// OLED display settings
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Ultrasonic sensor settings
#define TRIGGER_PIN  5
#define ECHO_PIN     18
#define MAX_DISTANCE 400
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE);

// NTC temperature sensor pin
#define TEMP_PIN 34
const int Buzzer = 15;
float temperature = 0;

// GPS module
TinyGPSPlus gps;
HardwareSerial gpsSerial(2);

// Blynk virtual pins
#define V_DISTANCE V1
#define V_TEMPERATURE V2
#define V_LATITUDE V3
#define V_LONGITUDE V4

void setup() {
  Serial.begin(115200);
  gpsSerial.begin(9600, SERIAL_8N1, 16, 17);  // RX=16, TX=17
  Blynk.begin(auth, ssid, pass);

  // Initialize the OLED display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.display();
  delay(2000);
  display.clearDisplay();
  
  pinMode(Buzzer, OUTPUT);
}

void loop() {
  Blynk.run();
  while (gpsSerial.available() > 0) {
    gps.encode(gpsSerial.read());
  }

  // Measure distance using the ultrasonic sensor
  unsigned int distance = sonar.ping_cm();
  Blynk.virtualWrite(V_DISTANCE, distance);

  // Measure temperature using the NTC sensor
  int sensorValue = analogRead(TEMP_PIN);
  float voltage = sensorValue * (3.3 / 4095.0);
  temperature = (voltage - 0.5) * 100;  // Convert to Celsius
  Blynk.virtualWrite(V_TEMPERATURE, temperature);

  // Check if temperature exceeds a threshold
  if (temperature > 50) {  // Example threshold for overcharge detection
    digitalWrite(Buzzer, HIGH);  // Turn on the buzzer
  } else {
    digitalWrite(Buzzer, LOW);  // Turn off the buzzer
  }

  // Display data on the OLED screen
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.print("Distance: ");
  display.print(distance);
  display.println(" cm");
  display.print("Temp: ");
  display.print(temperature);
  display.println(" C");

  if (gps.location.isValid()) {
    float latitude = gps.location.lat();
    float longitude = gps.location.lng();
    Blynk.virtualWrite(V_LATITUDE, latitude);
    Blynk.virtualWrite(V_LONGITUDE, longitude);

    display.print("Lat: ");
    display.print(latitude, 6);
    display.println();