/*	Lab Test Jul 2024
	 *	Name:	WANG JIXIN
    * Class:A
	 *	Date:19 Jul
	*/ 

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


bool LEDState = LOW;
unsigned long previousMillis = 0;
unsigned long interval = 750;

long previousMillisA = 0;
int intervalA =1500;
int adcRes = analogRead(A5); //analog

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* hostname = "broker.hivemq.com";
const char* espClientName = "DEIOT/S10251650";
int PORTNUM = 1883;

WiFiClient espClient;
PubSubClient client(espClient);


void setup_wifi()
{
  WiFi.begin(ssid, password);
  while(WiFi.status() != WL_CONNECTED )
  {
    delay(1000);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("Connected to ");
  Serial.println(ssid);
  Serial.print("Given IP by the router to ESP32 is ");
  Serial.println(WiFi.localIP());
}

void connectMQTT()
{
  while(!client.connected() )
  {
    Serial.println("Connecting to MQTT ...");
    if (client.connect(espClientName) ) 
    {
      Serial.println("Connected");
    }
    else
    {
      Serial.print("Failed with state ");
      Serial.print(client.state() );
      delay(1500);  //MQTT delay time
    }
  }
}

void callback(String topic, byte* payload, unsigned int length)
{
  String messageTemp;
  Serial.print("Message received in topic: ");
  Serial.print(topic);
  Serial.print(" length is: ");
  Serial.println(length);

  Serial.print("Data received from broker: ");
  for (int i = 0; i<length; i++)
  {
    Serial.print( (char)payload[i] );
    messageTemp += (char)payload[i];
  }
if (topic == "DEIOT/S10251650") 
  {
    if (messageTemp == "Alert")
    {
      digitalWrite(23, LOW); //light on
 
    }
    else  if (messageTemp == "ok")
    {
      digitalWrite(23,HIGH); //light off
    }

}

}

void setup_MQTT() 
{
  client.setServer(hostname, PORTNUM);
  client.setCallback(callback); 
}

void MQTTSubscribe()  ////ONLY ADD IN WHEN SURSCRIBE
{
  client.subscribe("DEIOT/S10251650"); 
}

void setup() 
{
	 Serial.begin(9600);  
	 pinMode(18,OUTPUT); //GreenLED
   pinMode(23,OUTPUT);
	 setup_wifi(); 
	 setup_MQTT(); 
}



void loop()
{
    unsigned long currentMillis = millis(); //LED 
    if (currentMillis - previousMillis >= interval)
      {
          previousMillis = currentMillis;
          LEDState = !LEDState;
          digitalWrite( 18,LEDState);
      }

       long currentMillisA = millis();  // analog 
   if (currentMillisA - previousMillisA >= intervalA)
   {
        previousMillisA = currentMillisA;
       int adcRes = analogRead( A5 );
        Serial.print("Analog Value =");
        Serial.println(adcRes);
   }
    if (adcRes > 2500)
  {
    client.publish("DEIOT/S10251650","Alert");
  }
  else
  {
    client.publish("DEIOT/S10251650","Ok");
  }
    
    String payload = String(adcRes);  //MQTT to text
  	client.publish("DEIOT/S10251650",payload.c_str()); //publish so phone can receieve them
  
	

	  if (!client.connected())
    {
    connectMQTT();
    }
    client.loop();



}