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

  #define TEMP_HUMID_PIN 14     
  #define DHT_MODEL DHT22   
  DHT envSensor(TEMP_HUMID_PIN, DHT_MODEL);

  #define SONIC_TRIG_PIN 5
  #define SONIC_ECHO_PIN 18

  #define LED_OVERHEAT 15        
  #define LED_DRYAIR 2   
  #define LED_PRESSURE_ALERT 4  
  #define LED_DIM_LIGHT 16    
  #define BUZZER_ALARM 17     

  int pressureSensorPin = 34;  
  int pressureRawValue;

  float echoTime_us, objectDistance_cm;
  #define LIGHT_SENSOR_PIN 33
  #define GAS_SENSOR_PIN 32
  const char* ssid = "Wokwi-GUEST";
  const char* password = "";
  const char* mqtt_server = "test.mosquitto.org";

  WiFiClient espClient;
  PubSubClient client(espClient);
  void wifi_config() {
   delay(10);
   Serial.println();

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

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

   randomSeed(micros());

  }

  void callback(char* topic, byte* payload, unsigned int length) {

   for (int i = 0; i < length; i++) {
     Serial.print((char)payload[i]);
   }}
  void reconnect() {
   while (!client.connected()) {
     Serial.print("Connecting to Mosquitto MQTT...");
     String clientId = "ESP32Client-";
     clientId += String(random(0xffff), HEX);
     if (client.connect(clientId.c_str())) {
       Serial.println("Connection Established");
       client.publish("/SmartHome/Publish", "hi");
       client.subscribe("/SmartHome/Subscribe");
     }}
  }
  void setup() {
    wifi_config();
    client.setServer(mqtt_server, 1883);
    client.setCallback(callback);
    Serial.begin(115200);
    Serial.println(F("Booting up Smart Home System..."));

    envSensor.begin();
    
    pinMode(SONIC_TRIG_PIN, OUTPUT);
    pinMode(SONIC_ECHO_PIN, INPUT);
    pinMode(LED_OVERHEAT, OUTPUT);
    pinMode(LED_DRYAIR, OUTPUT);
    pinMode(LED_PRESSURE_ALERT, OUTPUT);
    pinMode(LED_DIM_LIGHT, OUTPUT);
    pinMode(BUZZER_ALARM, OUTPUT);
    pinMode(GAS_SENSOR_PIN, INPUT);
  }

  void loop() {
    if (!client.connected()) {
    reconnect();
    }
    float currentTemp = envSensor.readTemperature();
    String temprature = String(currentTemp, 2);
    client.publish("/SmartHome/temprature", temprature.c_str()); 
    float currentHumidity = envSensor.readHumidity();
    String Humidity = String(currentHumidity, 2);
    client.publish("/SmartHome/Humidity", Humidity.c_str()); 
    pressureRawValue = analogRead(pressureSensorPin);
    int pressureConverted = map(pressureRawValue, 0, 4095, 0, 100);
    String Pressure = String(pressureConverted);
    client.publish("/SmartHome/Pressure", Pressure.c_str()); 
    digitalWrite(SONIC_TRIG_PIN, HIGH);
    delayMicroseconds(10);
    digitalWrite(SONIC_TRIG_PIN, LOW);
    echoTime_us = pulseIn(SONIC_ECHO_PIN, HIGH);
    objectDistance_cm = 0.017 * echoTime_us;
    String Distance = String(objectDistance_cm, 2);
    client.publish("/SmartHome/Distance", Distance.c_str()); 
    int lightIntensity = analogRead(LIGHT_SENSOR_PIN);
    int LightIntensity = map(lightIntensity, 0, 4095, 0, 100);
    String IntensityOfLight = String(LightIntensity);
    client.publish("/SmartHome/IntensityOfLight", IntensityOfLight.c_str()); 
    int gasReading = analogRead(GAS_SENSOR_PIN);
    int gasPPM = map(gasReading, 0, 4095, 0, 1000); 
    String Gas = String(gasPPM);
    client.publish("/SmartHome/Gas", Gas.c_str()); 
  
    Serial.println(F("================================================="));
    Serial.println(F("              SMART HOME STATUS REPORT           "));
    Serial.println(F("================================================="));

    if (!isnan(currentTemp) && !isnan(currentHumidity)) {
      Serial.print(F("Temperature: "));
      Serial.print(currentTemp);
      Serial.println(F(" °C"));
      
      Serial.print(F("Humidity: "));
      Serial.print(currentHumidity);
      Serial.println(F(" %"));
    } else {
      Serial.println(F("Error: Not able to retrieve the data of Temp/Humidity."));
    }

    Serial.print(F("Pressure: "));
    Serial.print(pressureConverted);
    Serial.println(F(" psi"));

    Serial.print(F("Distance to object: "));
    Serial.print(objectDistance_cm);
    Serial.println(F(" cm"));

    Serial.print(F("Intensity of Light: "));
    Serial.print(LightIntensity);
    Serial.println(F(" lux"));

    Serial.print(F("Gas concentration: "));
    Serial.print(gasPPM);
    Serial.println(" PPM");
    Serial.println(F("-------------------------------------------------"));
    
    
    if (currentTemp > 30) {
      digitalWrite(LED_OVERHEAT, HIGH);
      Serial.println(F("Alert: Activating cooling systems, Since high temprature detected."));
    } else {
      digitalWrite(LED_OVERHEAT, LOW);
    }

    if (currentHumidity < 40) {
      digitalWrite(LED_DRYAIR, HIGH);
      Serial.println(F("Alert: Activating humidifier, Since low humidity is detected"));
    } else {
      digitalWrite(LED_DRYAIR, LOW);
    }

    if (pressureConverted > 70) {
      digitalWrite(LED_PRESSURE_ALERT, HIGH);
      Serial.println(F("Alert: Pressure has exceeded the safe limits!"));
    } else {
      digitalWrite(LED_PRESSURE_ALERT, LOW);
    }

    if (objectDistance_cm < 30) {
      digitalWrite(BUZZER_ALARM, HIGH);  
      Serial.println(F("Alert: Object has been detected near garage. So opening the door."));
    } else {
      digitalWrite(BUZZER_ALARM, LOW);  
    }

    if (lightIntensity < 500) {
      digitalWrite(LED_DIM_LIGHT, HIGH);
      Serial.println(F("Alert: Low light has been detected. So turning on the lights."));
    } else {
      digitalWrite(LED_DIM_LIGHT, LOW);
      Serial.println(F("Lights are off since lightning is adequate."));
    }

    if (gasReading > 300) { 
      digitalWrite(BUZZER_ALARM, HIGH);
      Serial.println(F("Alert: Dangerous gas levels has been detected. So turning buzzer on."));
    } else {
      digitalWrite(BUZZER_ALARM, LOW);
    }

    Serial.println(F("================================================="));

    delay(3000);
  }