#include <SPI.h>
#include <SD.h>
#include <Wire.h>
#include <RTClib.h>
#include <OneWire.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 2
#define BUTTON_PIN 3
#define SD_CS_PIN 10

OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);
RTC_DS1307 rtc;

unsigned long lastLogTime = 0;
const unsigned long logInterval = 5000; // Log every 5 seconds

void setup() {
  Serial.begin(9600);
  sensors.begin();
  Wire.begin();
  rtc.begin();

  pinMode(BUTTON_PIN, INPUT_PULLUP);

  if (!rtc.isrunning()) {
    Serial.println("RTC is not running, setting default time.");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__))); // Set to compile time
  }

  Serial.println("Initializing SD card...");
  if (!SD.begin(SD_CS_PIN)) {
    Serial.println("SD card initialization failed!");
    return;
  }
  Serial.println("SD card initialized.");
}

void loop() {
  unsigned long currentTime = millis();

  // Log temperature and time every 5 seconds
  if (currentTime - lastLogTime >= logInterval) {
    lastLogTime = currentTime;

    sensors.requestTemperatures();
    float temperature = sensors.getTempCByIndex(0);
    DateTime now = rtc.now();

    File dataFile = SD.open("log.txt", FILE_WRITE);
    if (dataFile) {
      dataFile.print(now.hour());
      dataFile.print(":");
      dataFile.print(now.minute());
      dataFile.print(":");
      dataFile.print(now.second());
      dataFile.print(" ");
      dataFile.print(now.day());
      dataFile.print("/");
      dataFile.print(now.month());
      dataFile.print("/");
      dataFile.print(now.year());
      dataFile.print(" - Temp(C): ");
      dataFile.println(temperature);
      dataFile.close();
      Serial.println("Temperature and time logged.");
    } else {
      Serial.println("Error writing to SD card.");
    }
  }

  // Display log on button press
  if (digitalRead(BUTTON_PIN) == LOW) {
    delay(200); // Debounce
    File dataFile = SD.open("log.txt");
    if (dataFile) {
      Serial.println("Reading SD card contents:");
      while (dataFile.available()) {
        Serial.write(dataFile.read());
      }
      dataFile.close();
      Serial.println("\n--- End of Log ---");
    } else {
      Serial.println("Error reading from SD card.");
    }
  }
}