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

/* WiFi settings */
#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""
#define WIFI_CHANNEL 6 // Defining the WiFi channel speeds up the connection

/* MQTT Broker settings */
#define MQTT_SERVER "ccbb0920f6ae475ca798d2d08b80062b.s1.eu.hivemq.cloud"
#define MQTT_USER "ESP32"
#define MQTT_PASSWORD "ESP32Senai"
#define MQTT_PORT 8883

const char* pub_topic = "sensor";
const char* sub_topic = "senai/test";
const char* sensor_topic = "senai/sensor";

/* For no secure connection use WiFiClient: <WiFiClient espClient;> instead of WiFiClientSecure */
WiFiClientSecure espClient;
PubSubClient client(espClient);

static const char *root_ca PROGMEM = R"EOF(
-----BEGIN CERTIFICATE-----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=
)EOF";

void setup_wifi() {
  Serial.print("\nConnecting to ");
  Serial.println(WIFI_SSID);

  WiFi.mode(WIFI_STA);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD, WIFI_CHANNEL);

  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }

  Serial.println("Connected!");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
}

void connect_mqtt() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    String clientId = "ESPClient-"; // Create a random client ID
    clientId += String(random(0xffff), HEX);
    // Attempt to connect
    if (client.connect(clientId.c_str(), MQTT_USER, MQTT_PASSWORD)) {
      Serial.println("Success!");

      client.subscribe(sub_topic); // subscribe the topics here
      //client.subscribe(command2_topic); // subscribe the topics here
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds"); // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

//================================================ setup
void setup() {
  Serial.begin(9600);
  while (!Serial) delay(1);
  setup_wifi();

  pinMode(2, OUTPUT); // Initialize the BUILTIN_LED pin as an output

  espClient.setCACert(root_ca); // Configure TLS/SSL client certificates
  client.setServer(MQTT_SERVER, MQTT_PORT);
  client.setCallback(callback);
}

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

  // ---- example: how to publish sensor values every 5 sec
   unsigned long now = millis();
   unsigned long lastMsg;
   if (now - lastMsg > 5000) {
     lastMsg = now;
     int sensor1= random(50);       // replace the random value with your sensor value
     int sensor2= 20+random(80);    // replace the random value  with your sensor value
     publishMessage(pub_topic,String(sensor1),true);
     publishMessage(sensor_topic,String(sensor2),true);
  }
}

/* This callback is called every time we have a message from the broker */
void callback(char* topic, byte* payload, unsigned int length) {
  String incommingMessage = "";
  for (int i = 0; i < length; i++) incommingMessage+=(char)payload[i];
  Serial.println("Message arrived ["+String(topic)+"]"+incommingMessage);

  /* check the incomming message */
  if( strcmp(topic,sub_topic) == 0){
    if (incommingMessage.equals("on")) digitalWrite(2, HIGH); // Turn the LED on
    else if (incommingMessage.equals("off")) digitalWrite(2, LOW); // Turn the LED off
  }

  //  check for other commands
  /*  else  if( strcmp(topic,command2_topic) == 0){
             if (incommingMessage.equals("1")) {  } // do something else
          }
          */
}

//======================================= publising as string
void publishMessage(const char* topic, String payload , boolean retained){
  if (client.publish(topic, payload.c_str(), true))
    Serial.println("Message publised ["+String(topic)+"]: "+payload);
}