#include <ESP32Servo.h>
#include <ArduinoJson.h>
#include <WiFi.h>
#include <PubSubClient.h>

#define ServoPIN 18 //Signal Pin
#define GasPIN 34

// Connecting from Wokwi
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// Destination
const char* mqtt_server = "mqtt.thingsboard.cloud";
const char* mqtt_username = "MQ2 Servo";
const char* mqtt_password = "pqrs3241";
const char* clientID = "Gas Detector";

bool ServoState;

Servo myServo; // Servo obj

// RPC Callback
void callback(char* topic, byte* payload, unsigned int length)
{
    // Payload to String conversion
    char json[length + 1];
    memcpy(json, payload, length);
    json[length] = '\0';

    // Parse JSON
    StaticJsonDocument<200> doc;
    DeserializationError error = deserializeJson(doc, json);

    if (error) {
        Serial.println("JSON Parse Error");
        return;
    }

    String method = doc["method"];
    bool state = doc["params"];

    if (method == "setValue") {
      ServoState = state;
     //   if (state) {
       //     myServo.write(90);
         //   Serial.println("Servo ON");
        //}
        //else {
          //  myServo.write(0);
            //Serial.println("Servo OFF");
        //}

    }
}

// Client Definition
WiFiClient espClient;
PubSubClient client(espClient);

void setup_wifi() {

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println();
  Serial.println("WiFi Connected");

}

void reconnect() {

  while (!client.connected()) {

    Serial.print("Connecting MQTT...");

    if (client.connect(clientID, mqtt_username, mqtt_password)) {
      Serial.println("Connected");
      client.subscribe("v1/devices/me/rpc/request/+");
      
    }
    else {

      Serial.print("Failed, rc=");
      Serial.println(client.state());

      delay(2000);

    }

  }

}



void setup() {
  Serial.begin(115200);
  pinMode(ServoPIN, OUTPUT);

  //Callback setup
  client.setCallback(callback);

  // WiFi setup **
  setup_wifi();
client.setServer(mqtt_server,1883);

 myServo.attach(ServoPIN);
}

void loop() {
if (!client.connected())
  reconnect();

  client.loop();
  int gas = analogRead(GasPIN);
  Serial.println(gas);
  delay(1000);


  if (gas > 2439 &&  ServoState) {
    for (int angle = 0; angle <= 180; angle +=10){
      myServo.write(angle); // should give degrees as input
      delay(15);
    }
    for (int angle = 180; angle >= 0; angle -=10){
    myServo.write(angle); // should give degrees as input
    delay(15);
  }
}

  else{
 myServo.write(0); 
  }



// Sending data to Dashboard in 5 second intervals!
  unsigned long lastSend = 0;

  if (millis() - lastSend > 5000) {

    lastSend = millis();
    
    char payload[50];
    sprintf(payload,"{\"gas\":%d}",gas);

    client.publish("v1/devices/me/telemetry",payload);
  }
}