#include <WiFi.h>
#include <HTTPClient.h>
#include <ESP32Servo.h>

// WiFi credentials
const char* ssid = "Apple";
const char* password = "88888888";

// Server URL
const char* serverUrl = "http://192.168.43.83:5000/trainData";

// Ultrasonic sensor pins
#define TRIG_PIN 5
#define ECHO_PIN 18

// Servo pin
#define SERVO_PIN 13

Servo brakeServo;

void setup() {
  Serial.begin(115200);

  // Initialize WiFi
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");

  // Initialize ultrasonic sensor pins
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  // Initialize servo motor
  brakeServo.attach(SERVO_PIN);
}

void loop() {
  float distance = getDistance();
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  if (distance < 100) { // Threshold distance in cm
    activateBrakes();
    sendDataToServer(distance, "Brakes Activated");
  } else {
    deactivateBrakes();
    sendDataToServer(distance, "Normal Operation");
  }

  delay(1000);
}

float getDistance() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  long duration = pulseIn(ECHO_PIN, HIGH);
  return (duration * 0.0343) / 2;
}

void activateBrakes() {
  brakeServo.write(0); // Simulate brake activation
}

void deactivateBrakes() {
  brakeServo.write(90); // Simulate brake deactivation
}

void sendDataToServer(float distance, const char* status) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String(serverUrl) + "?distance=" + String(distance) + "&status=" + status;
    http.begin(url);
    int httpResponseCode = http.GET();
    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println("Server Response: " + response);
    } else {
      Serial.println("Error in sending GET request");
    }
    http.end();
  } else {
    Serial.println("WiFi not connected");
  }
}