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

// Update these with values suitable for your network.

const char* ssid = "Wokwi-GUEST"; // WiFi name
const char* password = "";  // WiFi password
const char* mqtt_server = "test.mosquitto.org";

String my_payload;
String my_topic;

WiFiClient ESP32;
PubSubClient client(ESP32);
// unsigned long lastMsg = 0;
// #define MSG_BUFFER_SIZE	(50)
// char msg[MSG_BUFFER_SIZE];
// int value = 0;

void setup_wifi() {

  delay(10);
  // We start by connecting to a WiFi network
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

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

  // randomSeed(micros());

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void callback(char* topic, byte* payload, unsigned int length) {
  
  // Serial.print("Message arrived [");
  // Serial.print(topic);
  // Serial.print("] ");
  
  String conc_payload;
  for (int i = 0; i < length; i++) {
    conc_payload += ((char)payload[i]);
  }
  my_payload = conc_payload;
  my_topic = topic;

  // // Switch on the LED if an 1 was received as first character
  // if ((char)payload[0] == '1') {
  //   digitalWrite(BUILTIN_LED, LOW);   // Turn the LED on (Note that LOW is the voltage level
  //   // but actually the LED is on; this is because
  //   // it is active low on the ESP-01)
  // } else {
  //   digitalWrite(BUILTIN_LED, HIGH);  // Turn the LED off by making the voltage HIGH
  // }

}

void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");

    // // Create a random client ID
    // String clientId = "ESP8266Client-";
    // clientId += String(random(0xffff), HEX);

    // Attempt to connect
    if (client.connect("ESP32")) {
      Serial.println("connected");
      // // Once connected, publish an announcement...
      // client.publish("outTopic", "hello world");
      // // ... and resubscribe
      client.subscribe("ESP32_ASSIGN");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

void setup() {
  pinMode(17, OUTPUT);     // Initialize the GPIO2 pin as an output
  pinMode(15, OUTPUT);    // Initialize the GPIO15 pin as an output
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void wifi() {
  if (WiFi.status()) {
    digitalWrite(17, HIGH);
  }
  else {
    digitalWrite(17, LOW);
  }
}

void mqtt() {
  if (client.connected()) {
    digitalWrite(15, HIGH);
  }
  else {
    digitalWrite(15, LOW);
  }
}

void loop() {

  if (!client.connected()) {
    reconnect();
  }
  client.loop();
  wifi();
  mqtt();

  // unsigned long now = millis();
  // if (now - lastMsg > 2000) {
  //   lastMsg = now;
  //   ++value;
  //   snprintf (msg, MSG_BUFFER_SIZE, "hello world #%ld", value);
  //   Serial.print("Publish message: ");
  //   Serial.println(msg);
  //   client.publish("outTopic", msg);
  // }
}