#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#include <SPI.h>

// Set up the LCD using I2C
LiquidCrystal_I2C lcd(0x27, 16, 2); // Adjust I2C address to your specific LCD

// Set up DHT22 for temperature and humidity
#define DHTPIN 2 // Pin connected to DHT22 data pin
#define DHTTYPE DHT22 // Define the type of DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// SPI Barometric Pressure Sensor
#define CS_PIN 10 // Chip Select
#define SCK_PIN 13 // SPI Clock
#define SDI_PIN 11 // SPI Data In (MOSI)
#define SDO_PIN 12 // SPI Data Out (MISO)

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  
  // Initialize LCD
  lcd.begin(16, 2); // Specify the number of columns and rows
  lcd.backlight();

  // Initialize SPI
  pinMode(CS_PIN, OUTPUT);
  digitalWrite(CS_PIN, HIGH); // Disable the sensor
  SPI.begin();
  SPI.setClockDivider(SPI_CLOCK_DIV16); // Adjust as needed for your sensor

  // Initialize DHT22 sensor
  dht.begin();
  
  // Display startup message
  lcd.setCursor(0, 0);
  lcd.print("Biodigester");
  lcd.setCursor(0, 1);
  lcd.print("Monitoring...");
  delay(2000);
  lcd.clear();
}

void loop() {
  // Read temperature and humidity from DHT22
  float temperature = dht.readTemperature();  // Read temperature in Celsius
  float humidity = dht.readHumidity();         // Read humidity percentage

  // Read barometric pressure from SPI sensor
  digitalWrite(CS_PIN, LOW); // Enable the sensor
  byte pressureData[3];
  
  for (int i = 0; i < 3; i++) {
    pressureData[i] = SPI.transfer(0x00); // ermm data
  }
  
  digitalWrite(CS_PIN, HIGH); // Disable the sensor

  // Convert SPI data to pressure 
  float pressure = (pressureData[0] << 16 | pressureData[1] << 8 | pressureData[2]) / 100.0;

  // Display data on LCD
  lcd.setCursor(0, 0);
  lcd.print("T1 T:");
  lcd.print(temperature);
  lcd.print("C H:");
  lcd.print(humidity);
  lcd.print("%");
  
  lcd.setCursor(0, 1);
  lcd.print("P:");
  lcd.print(pressure);
  lcd.print("hPa");

  // Output to serial monitor (for debugging)
  Serial.print("Temperature: "); Serial.print(temperature); Serial.println(" *C");
  Serial.print("Humidity: "); Serial.print(humidity); Serial.println(" %");
  Serial.print("Pressure: "); Serial.print(pressure); Serial.println(" hPa");
  
  delay(2000); // Wait 2 seconds before updating data again