#include <BluetoothSerial.h>
#include <DHT.h>
#include <Wire.h>
#include <RTClib.h>
#include <LiquidCrystal_I2C.h>
#include <FastLED.h>

#define DHTPIN 4  // DHT22 data pin
#define DHTTYPE DHT22

#define RTC_SDA 21  // RTC data pin
#define RTC_SCL 22  // RTC clock pin

#define PHOTO_PIN 34  // Photoresistor pin

#define BUTTON_PIN 32
#define LED_PIN 14
#define NUM_LEDS 18
#define LED_TYPE WS2812B
#define COLOR_ORDER GRB

CRGB leds[NUM_LEDS];
BluetoothSerial SerialBT;
DHT dht(DHTPIN, DHTTYPE);
RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 20, 4);  // Set the LCD address to 0x27 for a 20x4 display

bool isFahrenheit = false; // Flag to track temperature unit
unsigned long previousMillis = 0;
const long interval = 5000; // Interval to gather data (5 seconds)
const int numDataPoints = 30; // Number of data points to chart
float temperatureData[numDataPoints];
float humidityData[numDataPoints];
int lightData[numDataPoints];
int currentIndex = 0;

void setup() {
  Serial.begin(115200);
  SerialBT.begin("ESP32_BT"); // Bluetooth device name
  Serial.println("The device started, now you can pair it with bluetooth!");

  // Initialize DHT sensor
  dht.begin();

  // Initialize RTC
  Wire.begin();
  rtc.begin();

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

  // Initialize LED
  FastLED.addLeds<LED_TYPE, LED_PIN, COLOR_ORDER>(leds, NUM_LEDS);

  // Boot-up sequence (blue color)
  fill_solid(leds, NUM_LEDS, CRGB(0, 0, 255)); // Blue color
  FastLED.show();

  // Initialize button
  pinMode(BUTTON_PIN, INPUT_PULLUP);
}

void loop() {
  // Gather sensor data
  if (millis() - previousMillis >= interval) {
    previousMillis = millis();

    // Read sensor data
    float temperature = dht.readTemperature();
    float humidity = dht.readHumidity();
    // Read time from RTC
    DateTime now = rtc.now();
    int lightLevel = analogRead(PHOTO_PIN); 

    // Store data
    temperatureData[currentIndex] = temperature;
    humidityData[currentIndex] = humidity;
    lightData[currentIndex] = lightLevel;

    currentIndex++;
    if (currentIndex >= numDataPoints) {
      currentIndex = 0;
    }
  }

  // Check if the button is pressed
  if (digitalRead(BUTTON_PIN) == LOW) {
    // Button pressed, toggle temperature unit
    isFahrenheit = !isFahrenheit;
    delay(200); // Debounce delay
  }

  // Display sensor data on LCD
  displaySensorData();

  // Check for low light level
  if (analogRead(PHOTO_PIN) < 100) {
    // Low light detected, turn LEDs on white
    fill_solid(leds, NUM_LEDS, CRGB::White);
  } else {
    // Normal light, turn LEDs off
    fill_solid(leds, NUM_LEDS, CRGB::Black);
  }
  FastLED.show();

  // If Bluetooth is connected, send data over Bluetooth
  if (SerialBT.available()) {
    sendBluetoothData();
  } else {
    // After 20 seconds without Bluetooth connection, display data on screen
    if (millis() - previousMillis >= 20000) {
      displayDataOnScreen();
    }
  }
}

// Display sensor data function
void displaySensorData() {
  lcd.clear();
  lcd.setCursor(0, 0);

  // Display time and date
  DateTime now = rtc.now();
  lcd.print(now.month(), DEC);
  lcd.print('/');
  lcd.print(now.day(), DEC);
  lcd.print('/');
  lcd.print(now.year(), DEC);
  lcd.print(" ");
  lcd.print(now.hour(), DEC);
  lcd.print(':');
  lcd.print(now.minute(), DEC);
  lcd.print(':');
  lcd.print(now.second(), DEC);
  lcd.println();

  // Display temperature
  lcd.print("Temperature: ");
  if (isFahrenheit) {
    lcd.print(dht.readTemperature(true)); // Convert to Fahrenheit
    lcd.println(" F");
  } else {
    lcd.print(dht.readTemperature());
    lcd.println(" C");
  }

  // Display humidity
  lcd.print("Humidity: ");
  lcd.print(dht.readHumidity());
  lcd.println(" %");

  // Display light level
  lcd.print("Light Level: ");
  lcd.println(analogRead(PHOTO_PIN));

  // Chart sensor data (if needed)
}

// Send data over Bluetooth
void sendBluetoothData() {
  SerialBT.print("Time: ");
  SerialBT.print(rtc.now().timestamp());
  SerialBT.print(", Temperature: ");
  SerialBT.print(isFahrenheit ? dht.readTemperature(true) : dht.readTemperature());
  SerialBT.print(" ");
  SerialBT.print(isFahrenheit ? "F" : "C");
  SerialBT.print(", Humidity: ");
  SerialBT.print(dht.readHumidity());
  SerialBT.print(" %");
  SerialBT.print(", Light Level: ");
  SerialBT.println(analogRead(PHOTO_PIN));
}

// Display data on screen function
void displayDataOnScreen() {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temperature: ");
  lcd.print(isFahrenheit ? dht.readTemperature(true) : dht.readTemperature());
  lcd.println(isFahrenheit ? " F" : " C");
  lcd.print("Humidity: ");
  lcd.print(dht.readHumidity());
  lcd.println(" %");
  lcd.print("Light Level: ");
  lcd.println(analogRead(PHOTO_PIN));
}