#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <DHT.h>

// Pin definitions
const int firePin = 27;
const int dhtPin = 15;
const int voltagePin = 35;
const int relay1Pin = 19;
const int relay2Pin = 18;
const int sw1Pin = 33;
const int sw2Pin = 32;

// Threshold values
const int fireThreshold = 80;
const int tempThreshold = 80;
const float voltageThreshold = 10.3;

// DHT setup
#define DHTTYPE DHT22
DHT dht(dhtPin, DHTTYPE);

// OLED setup
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Variables
float temperature = 0.0;
float humidity = 0.0;
int fireValue = 0;
float voltage = 0.0;

void setup() {
  // Initialize Serial
  Serial.begin(115200);

  // Initialize OLED
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 allocation failed");
    for (;;);
  }
  display.clearDisplay();
  display.display();

  // Initialize DHT sensor
  dht.begin();

  // Set pin modes
  pinMode(relay1Pin, OUTPUT);
  pinMode(relay2Pin, OUTPUT);
  pinMode(sw1Pin, INPUT);
  pinMode(sw2Pin, INPUT);
}

void loop() {
  // Read temperature and humidity
  temperature = dht.readTemperature();
  humidity = dht.readHumidity();

  // Read fire sensor value from potentiometer and map to 0-100
  fireValue = map(analogRead(firePin), 0, 4095, 0, 100);

  // Read voltage (mapped from 0.0V - 12.5V)
  voltage = map(analogRead(voltagePin), 0, 4095, 0.0, 12.5);

  // Read switch states
  bool sw1State = digitalRead(sw1Pin);
  bool sw2State = digitalRead(sw2Pin);

  // Control relay 1
  if (sw1State == HIGH) {
    if (temperature < tempThreshold && fireValue < fireThreshold && voltage > voltageThreshold) {
      digitalWrite(relay1Pin, HIGH);
    } else {
      digitalWrite(relay1Pin, LOW);
    }
  } else {
    digitalWrite(relay1Pin, LOW);
  }

  // Control relay 2
  if (sw2State == HIGH) {
    if (temperature < tempThreshold && fireValue < fireThreshold && voltage > voltageThreshold) {
      digitalWrite(relay2Pin, HIGH);
    } else {
      digitalWrite(relay2Pin, LOW);
    }
  } else {
    digitalWrite(relay2Pin, LOW);
  }

  // Update OLED display
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(WHITE);

  // Display system name
  display.setCursor(0, 0);
  display.println("BMS SYS");

  // Display relay status
  display.setCursor(0, 15);
  display.print("R1: ");
  display.println(digitalRead(relay1Pin) ? "ON" : "OFF");
  
  display.setCursor(64, 15);
  display.print("R2: ");
  display.println(digitalRead(relay2Pin) ? "ON" : "OFF");

  // Display sensor values
  display.setCursor(0, 35);
  display.print("Temp: ");
  display.print(temperature);
  display.print("C");

  display.setCursor(0, 45);
  display.print("Fire: ");
  display.print(fireValue > fireThreshold ? "Alert !!!" : "Safe !!!");

  display.setCursor(0, 55);
  display.print("Volt: ");
  display.print(voltage);
  display.print("V");

  // Display everything
  display.display();

  // Debug prints
  Serial.print("Temp: "); Serial.print(temperature);
  Serial.print(" | Fire: "); Serial.print(fireValue);
  Serial.print(" | Voltage: "); Serial.print(voltage);
  Serial.print(" | R1: "); Serial.print(digitalRead(relay1Pin));
  Serial.print(" | R2: "); Serial.println(digitalRead(relay2Pin));

  // Delay for stability
  delay(1000);
}