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

const char* ssid = "ssid";    //Add SSID
const char* pass = "ssid password";   // Add Wi-Fi password
const char* brokerUser = ("user"); // Add broker username
const char* brokerPass = ("pass"); // Add broker password
const char* broker = ("broker.emqx.io");
const char* outTopic = ("test1");  //Add Server name
const char* inTopic = ("test1"); //Add same name as in outTopic

//String joy_d; //String to store data from server
char messages[100];
String MegaData;

#define RXD2 16    //ESP32 UART2 pins
#define TXD2 17

WiFiClient espClient;
PubSubClient client(espClient);

void setupwifi() {
  delay(100);
  Serial.println("\nConnecting to");
  Serial.println(ssid);

  WiFi.begin(ssid, pass);

  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print("-");
  }
  Serial.print("\nConnected to");
  Serial.println(ssid);
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("\nConnecting to");
    Serial.println(broker);
    if (client.connect("asdf123", brokerUser, brokerPass)) {
      Serial.println("\nConnected to");
      Serial.println(broker);
      client.subscribe(inTopic);
    } else {
      Serial.println("\nTrying connect again");
      delay(5000);
    }
  }
}


void callback(char* topic, byte* payload, unsigned int length) {  // This portion reads data from the server
  String messageout = "";
  for (int i = 0; i < length; i++) {
    ((char) payload[i]);
    messageout += (char) payload[i];

    if (messageout.indexOf("Ship_destroy") >= 0) {
      Serial1.println("Shipping station destroyed");
    }
    if (messageout.indexOf("Right") >= 0) {    //If anywhere in the server data there are consecutive characters xval=255, string joy_d="Right"
      Serial1.println("right");
    }
    if (messageout.indexOf("Left") >= 0) {    //If anywhere in the server data there are consecutive characters xval=0, string joy_d="Left"
      Serial1.println("left");
    }
    if (messageout.indexOf("Up") >= 0) {
      Serial1.println("up");
    }
    if (messageout.indexOf("Down") >= 0) {
      Serial1.println("down");
    }
    if (messageout.indexOf("Stop") >= 0) {
      Serial1.println("stop");
    }
  }
}

void setup() {
  Serial.begin(115200);
  Serial2.begin(9600, SERIAL_8N1, RXD2, TXD2);  // ESP32 UART 2 pins
  Serial1.begin(9600, SERIAL_8N1, RXD2, TXD2); //Mega UART 1 pins
  setupwifi();
  client.setServer(broker, 1883);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  if (Serial2.available()) {    // This portion of the code reads the Arduino Mega serial monitor output through the ESP32 UART2 pins. It then sends the data to the MQTT server.
    String MegaData = Serial2.readString(); // Changes the string to a char and publishes to the server.
    Serial.println(MegaData);
    MegaData.toCharArray(messages, 10);
    client.publish(outTopic, messages);
    delay(500);
  }
}