#include <OneWire.h>
#include <DallasTemperature.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <stdbool.h>

// Data wire is plugged into port 2 on the Arduino
#define ONE_WIRE_BUS 2
#define LED_PIN 3
#define BUZZER_PIN 4
#define BUTTON_PIN 5

// Create OneWire instance
OneWire oneWire(ONE_WIRE_BUS);

// Pass oneWire reference to DallasTemperature library
DallasTemperature sensors(&oneWire);

// Initialize the LCD library with the I2C address and dimensions
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Define temperature thresholds
#define TEMP_THRESHOLD 50.0 // Example threshold temperature in Celsius

// Structure to hold the fire alarm state
struct FireAlarm {
    bool isHighTemp;
    bool alarmActive;
};

// Function prototypes
void initializeSystem(struct FireAlarm *alarm);
void checkTemperature(struct FireAlarm *alarm);
void updateDisplay(struct FireAlarm *alarm);
void handleAlarm(struct FireAlarm *alarm);

void setup() {
    // Initialize components
    struct FireAlarm alarm;
    initializeSystem(&alarm);
}

void loop() {
    static struct FireAlarm alarm;
    // Check temperature
    checkTemperature(&alarm);

    // Update display and alarm status
    updateDisplay(&alarm);
    handleAlarm(&alarm);

    // Add a small delay to avoid rapid looping
    delay(2000);
}

void initializeSystem(struct FireAlarm *alarm) {
    // Start serial communication for debugging
    Serial.begin(9600);
    // Initialize the temperature sensor
    sensors.begin();
    // Set pin modes
    pinMode(LED_PIN, OUTPUT);
    pinMode(BUZZER_PIN, OUTPUT);
    pinMode(BUTTON_PIN, INPUT_PULLUP);

    // Initialize LCD
    lcd.init();
    lcd.backlight();

    // Initialize alarm state
    alarm->isHighTemp = false;
    alarm->alarmActive = false;
}

void checkTemperature(struct FireAlarm *alarm) {
    // Request temperature measurement
    sensors.requestTemperatures();
    float tempC = sensors.getTempCByIndex(0);

    // Print temperature for debugging
    Serial.print("Current temperature: ");
    Serial.print(tempC);
    Serial.println(" C");

    // Check if temperature exceeds threshold
    if (tempC >= TEMP_THRESHOLD) {
        alarm->isHighTemp = true;
        alarm->alarmActive = true;
    } else {
        alarm->isHighTemp = false;
    }
}

void updateDisplay(struct FireAlarm *alarm) {
    lcd.clear();
    if (alarm->isHighTemp) {
        lcd.print("Fire, danger");
    } else {
        lcd.print("No fire, safe");
    }
}

void handleAlarm(struct FireAlarm *alarm) {
    if (alarm->alarmActive==false) {
        
        digitalWrite(LED_PIN, LOW);
        digitalWrite(BUZZER_PIN, LOW);
        tone(BUZZER_PIN, -500);
        
    } else {
      digitalWrite(LED_PIN, HIGH);
        digitalWrite(BUZZER_PIN, HIGH);
        tone(BUZZER_PIN, 1);
        
    }

    // Check if the button is pressed to reset the alarm
    if (digitalRead(BUTTON_PIN) == HIGH) {
        alarm->alarmActive = false;
    }
}