#include <WiFi.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>
const char* ssid = "Wokwi-GUEST";
const char* password = "";

const char* mqttServer = "demo.thingsboard.io";
const int mqttPort = 1883; // Default MQTT port
const char* mqttUser = ""; // If your MQTT server requires authentication
const char* mqttPassword = ""; // If your MQTT server requires authentication
const char* deviceToken = "3PYgZqEMhK5u3Lu4ZKvK";

const char* switchStateTopic = "v1/devices/me/attributes";
const char* switchControlTopic = "v1/devices/me/rpc/request/+";

const int ledPin = 2;   // Pin number where the LED is connected
const int ledPin2 = 47;

WiFiClient wifiClient;
PubSubClient mqttClient(wifiClient);

void setup() {
  Serial.begin(115200);
  pinMode(ledPin, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  setupWiFi();
  setupMQTT();
}

void setupWiFi() {
  Serial.print("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("Connected to WiFi!");
}

void setupMQTT() {
  mqttClient.setServer(mqttServer, mqttPort);
  mqttClient.setCallback(callback);
  mqttClient.subscribe("v1/devices/me/attributes/ledState");
  reconnect();
}

void callback(char* topic, byte* payload, unsigned int length) {
  String message = "";
  for (int i = 0; i < length; i++) {
    message += (char)payload[i];
  }
  Serial.println("RPC Request received on topic: " + String(topic) + ", payload: " + message);
  
  // Parse the JSON payload to extract method and parameters
  DynamicJsonDocument doc(512);
  DeserializationError error = deserializeJson(doc, payload, length);
  if (error) {
    Serial.println("Failed to parse JSON payload");
    return;
  }
  
  // Extract method and parameters from the JSON payload
  const char* method = doc["method"];
  bool params = doc["params"];

  // Check if the method is "setValue" and take appropriate action
  if (strcmp(method, "setLedValue") == 0) {
    Serial.println("Method: setLedValue, Params: " + String(params));
    // Toggle LED state based on the received parameter value
    digitalWrite(ledPin, params ? HIGH : LOW);
    if (params==HIGH){
      String payload = "{\"LED VALUE\":1}";
      char attributes[1000];
      payload.toCharArray(attributes, 1000);
      mqttClient.publish("v1/devices/me/telemetry", attributes);
    }
    else{
      String payload = "{\"LED VALUE\":0}";
      char attributes[1000];
      payload.toCharArray(attributes, 1000);
      mqttClient.publish("v1/devices/me/telemetry", attributes);
    }
  }
  if (strcmp(method, "setValue") == 0) {
    Serial.println("Method: setValue, Params: " + String(params));
    // Toggle LED state based on the received parameter value
    digitalWrite(ledPin2, HIGH);
    delay(1000);
    digitalWrite(ledPin2, LOW);
    // if (params==1){
    //   String payload = "{\"LED VALUE\":1}";
    //   char attributes[1000];
    //   payload.toCharArray(attributes, 1000);
    //   mqttClient.publish("v1/devices/me/telemetry", attributes);
    // }
    // else{
    //   String payload = "{\"LED VALUE\":0}";
    //   char attributes[1000];
    //   payload.toCharArray(attributes, 1000);
    //   mqttClient.publish("v1/devices/me/telemetry", attributes);
    // }
  }
}


void reconnect() {
  // Loop until we're reconnected
  while (!mqttClient.connected()) {
    Serial.print("Attempting MQTT connection...");
    // Attempt to connect
    if (mqttClient.connect("ESP32Client", deviceToken, NULL)) {
      Serial.println("connected");
      mqttClient.subscribe(switchControlTopic);
    } else {
      Serial.print("failed, rc=");
      Serial.print(mqttClient.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void loop() {
  if (!mqttClient.connected()) {
    reconnect();
  }
  mqttClient.loop();
}