// Template and device credentials for Blynk
#define BLYNK_TEMPLATE_ID "TMPL6YAS5_ss3"
#define BLYNK_TEMPLATE_NAME "IoT Smart Exhaust Fan"
#define BLYNK_PRINT Serial  // Directs Blynk messages to the serial port

#include <WiFi.h>  // Include WiFi library for ESP32
//#include <BlynkSimpleEsp32.h>  // Disabled for Wokwi simulation
#include "DHT.h"  // Include DHT sensor library

// WiFi credentials for Wokwi simulation
const char auth[] = "SIMULATION_MODE";   // Placeholder for Blynk token
const char ssid[] = "Wokwi-GUEST";       // Wokwi default SSID
const char pass[] = "";                  // No password for Wokwi WiFi
const int channel = 6;                   // Wokwi channel

// Pin configuration
#define DHTPIN 22  // DHT sensor pin
#define DHTTYPE DHT11  // Type of DHT sensor

const int gasSensorPin = 34;  // Gas sensor pin
const int relayPin = 23;      // Relay module pin

const int gasThreshold = 20;  // Gas level threshold for triggering the relay

DHT dht(DHTPIN, DHTTYPE);  // Initialize DHT sensor

bool manualMode = false;  // Flag to track if the relay is in manual mode

void setup()
{
  Serial.begin(115200);  // Start serial communication at 115200 baud rate
  dht.begin();           // Initialize DHT sensor

  // Connect to Wokwi WiFi
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, pass, channel);
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println("\nConnected to Wokwi WiFi");

  pinMode(relayPin, OUTPUT);    // Set relay pin as output
  pinMode(gasSensorPin, INPUT); // Set gas sensor pin as input

  digitalWrite(relayPin, HIGH);  // Active LOW relay OFF initially

  delay(2000);  // Wait for 2 seconds before proceeding
}

// Function to handle manual relay control (Simulation only)
void setManualRelayControl(int relayControl)
{
  manualMode = (relayControl == 1);

  if (manualMode)
  {
    digitalWrite(relayPin, LOW);  // Active LOW relay ON
  }
  else
  {
    digitalWrite(relayPin, HIGH); // Active LOW relay OFF
  }

  Serial.print("Manual Mode Relay Status: ");
  Serial.println(relayControl ? "ON" : "OFF");
}

void loop()
{
  int sensorValue = analogRead(gasSensorPin);  // Read gas sensor value
  int gas_percentage = map(sensorValue, 0, 4095, 0, 100);  // Convert to percentage

  float humidity = dht.readHumidity();      // Read humidity from DHT sensor
  float temperature = dht.readTemperature();// Read temperature from DHT sensor

  // Debug raw MQ-2 reading
  Serial.print("Raw MQ-2 Value: ");
  Serial.println(sensorValue);

  // Check if sensor readings are valid
  if (isnan(humidity) || isnan(temperature))
  {
    Serial.println(F("Failed to read from DHT sensor!"));
    return;
  }

  // Print sensor values to the Serial Monitor
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println("%");

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println("°C");

  Serial.print("Gas Percentage: ");
  Serial.print(gas_percentage);
  Serial.println("%");

  // Automatic control logic based on gas levels
  if (!manualMode)
  {
    if (gas_percentage > gasThreshold)
    {
      digitalWrite(relayPin, LOW);  // Active LOW relay ON
      Serial.println("⚠️ Gas detected! Relay ON");
    }
    else
    {
      digitalWrite(relayPin, HIGH); // Active LOW relay OFF
      Serial.println("✅ Safe level. Relay OFF");
    }
  }

  // Simulation: Replace Blynk.virtualWrite with Serial outputs
  Serial.print("Send to Dashboard -> Gas: ");
  Serial.print(gas_percentage);
  Serial.print("% | Temp: ");
  Serial.print(temperature);
  Serial.print("°C | Humidity: ");
  Serial.print(humidity);
  Serial.println("%");

  Serial.println("-----------------------------");

  delay(1000);  // Wait for a second before next loop iteration
}