wireless control using http protocol - Wokwi ESP32, STM32, Arduino Simulator

#include <WiFi.h>
#include <WebServer.h>

// Replace with your network credentials
const char* ssid = "akash";
const char* password = "63513696773";

// Set the GPIO pin for the relay
const int relayPin = 4;

// Create a web server object that listens for HTTP requests on port 80
WebServer server(80);

// HTML content for the web page
const char* htmlPage = R"rawliteral(
<!DOCTYPE html>
<html>
<head>
  <title>ESP32 Bulb Control</title>
</head>
<body>
  <h1>Bulb Control</h1>
  <button onclick="toggleBulb('on')">Turn On</button>
  <button onclick="toggleBulb('off')">Turn Off</button>
  <script>
    function toggleBulb(state) {
      var xhr = new XMLHttpRequest();
      xhr.open("GET", "/bulb?state=" + state, true);
      xhr.send();
    }
  </script>
</body>
</html>
)rawliteral";

// Handle requests to root URL "/"
void handleRoot() {
  server.send(200, "text/html", htmlPage);
}

// Handle requests to "/bulb" URL
void handleBulb() {
  String state = server.arg("state");
  if (state == "on") {
    digitalWrite(relayPin, LOW); // LOW to turn on the relay (depends on your relay module)
  } else if (state == "off") {
    digitalWrite(relayPin, HIGH); // HIGH to turn off the relay (depends on your relay module)
  }
  server.send(200, "text/plain", "OK");
}

void setup() {
  // Initialize serial and wait for port to open
  Serial.begin(115200);

  // Initialize the relay pin as an output
  pinMode(relayPin, OUTPUT);
  digitalWrite(relayPin, HIGH); // Ensure relay is off

  // Connect to Wi-Fi network
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected.");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());

  // Set up web server routes
  server.on("/", handleRoot);
  server.on("/bulb", handleBulb);

  // Start the web server
  server.begin();
  Serial.println("HTTP server started");
}

void loop() {
  // Handle client requests
  server.handleClient();
}