/* Virtuino IoT
 * Example: MQTT communication between ESP32/ESP8266 and Thingspeak MQTT 
   Updated: Mar/26/2023
   Created by: Ilias Lamprou
   https://virtuino.com

   On the code below you have to replace:
   1. Your wifi ssid and password
   2. The Thingspeak channel id
   3. The Thingspeak MQTT Device Credentials
*/

//--------------------------------------------------------------------
//------------------------ Settings-----------------------------------
//--------------------------------------------------------------------
char ssid[] = "Wokwi-GUEST"; //  Change this to your network SSID (name).
char pass[] = "";    // Change this your network password

//------ MQTT broker settings and topics
const char* mqtt_server = "mqtt3.thingspeak.com";


//-- published settings
const char* publishTopic ="channels/2383455/publish";   //REPLACE THE NUMBER 114938 WITH YOUR channel ID  

//-- subscribed settings Virtuino command 1   
const char* subscribeTopicFor_Command_1="channels/2383455/subscribe/fields/field1";   //REPLACE THE NUMBER 114938 WITH YOUR channel ID  
//const char* subscribeTopicFor_Command_2="channels/114938/subscribe/fields/field2";   //REPLACE THE NUMBER 114938 WITH YOUR channel ID  

const unsigned long postingInterval = 20L * 1000L; // Post data every 20 seconds.

//------------------------ Variables-----------------------------------
//-------------------------------------------------------------------------
#ifdef ESP8266
 #include <ESP8266WiFi.h>  
 #else
 #include <WiFi.h>  
#endif
 
#include <PubSubClient.h>
#include <WiFiClient.h>
WiFiClient espClient;
PubSubClient client(espClient);  // Download the library PubSubClient from the arduino library manager

unsigned long lastUploadedTime = 0;

//==========================================
void setup_wifi() {
  delay(10);
  Serial.print("\nConnecting to ");
  Serial.println(ssid);

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

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  randomSeed(micros());
  Serial.println("\nWiFi connected\nIP address: ");
  Serial.println(WiFi.localIP());
}

//=====================================
void reconnect() {
  // Loop until we're reconnected
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
      //client.connect("cliend ID", "username","password") Replace with your Thingspeak MQTT Device Credentials
    if (client.connect("HhcoKTERBSM4DjgoIjwtBgc", "HhcoKTERBSM4DjgoIjwtBgc","AZBAiZGJ0LCzsuvmPDr4OGWj")) {  
      Serial.println("connected");
      client.subscribe(subscribeTopicFor_Command_1);   // subscribe the topics here
      //client.subscribe(command2_topic);   
      
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");   // Wait 5 seconds before retrying
      delay(5000);
    }
  }
}

//========================================= messageReceived
void messageReceived(String &topic, String &payload) {
 Serial.println("incoming: " + topic + " - " + payload);
 
  //-- check for Virtuino Command 1
  if (topic==subscribeTopicFor_Command_1){
        Serial.println("Command 1 = "+payload);
        int v = payload.toInt();
        if (v>0) digitalWrite(LED_BUILTIN,HIGH);
        else digitalWrite(LED_BUILTIN,LOW);
   }

  /*//-- check for Virtuino Command 1
  if (topic==subscribeTopicFor_Command_2){
        Serial.println("Command 2 = "+payload);
   }
   */
  
}

//========================================= setup
//=========================================
void setup() {
  pinMode(LED_BUILTIN,OUTPUT);
  Serial.begin(9600);
  while (!Serial) delay(1);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}


//========================================= loop
//=========================================
void loop() {
  if (!client.connected()) reconnect();
  client.loop();
 
  if (millis() - lastUploadedTime > postingInterval) { // The uploading interval must be > 15 seconds 
    int sensorValue_1 = random(100); // replace with your sensor value
    int sensorValue_2=random(100);  // replace with your sensor value
    //int sensorValue_3=random(100);  // if you want to use three sensors enable this line
    
    String dataText = String("field1=" + String(sensorValue_1)+ "&field2=" + String(sensorValue_2)+"&status=MQTTPUBLISH");
    //String dataText = String("field1=" + String(sensorValue_1)+ "&field2=" + String(sensorValue_2)+"&field3=" + String(sensorValue_3)); // example for publish tree sensors
    publishMessage(publishTopic,dataText,true);    
    lastUploadedTime = millis();
  }
  
 }

 
//=======================================  
// This void 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,subscribeTopicFor_Command_1) == 0){
     if (incommingMessage.equals("1")) digitalWrite(BUILTIN_LED, LOW);   // Turn the LED on 
     else digitalWrite(BUILTIN_LED, HIGH);  // Turn the LED off 
  }
}



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