#include <Toggle.h>
#include "RTClib.h"
#include <Keypad.h>
#include <SD.h>
#define CS_PIN 10
const char * logFileName = "data.txt";

const uint8_t ROWS = 4;
const uint8_t COLS = 3;
char keys[ROWS][COLS] = {
  { '1', '2', '3'},
  { '4', '5', '6'},
  { '7', '8', '9'},
  { '*', '0', '#'}
};

uint8_t colPins[COLS] = { 5, 4, 3 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 9, 8, 7, 6 }; // Pins connected to R1, R2, R3, R4
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

const byte dumpButtonPin = 2;
Toggle dumpButton;

RTC_DS1307 rtc;


void dumpData() {

  File logFile = SD.open(logFileName);
  if (logFile) {
    Serial.println(logFileName);
    while (logFile.available()) {
      Serial.write(logFile.read());
    }
    logFile.close();
    Serial.println("\n------------");
  } else {
    Serial.println("error opening log file!");
  }
}

void handleKeypad() {
  const byte codeLength = 4;
  static char code[codeLength + 1];
  static byte codePos = 0;
  char key = keypad.getKey();
  if (key != NO_KEY) {
    if ((codePos == codeLength - 1) && (key == '#' || key == '*')) { // if we have the 4 digits and user validates
      File logFile = SD.open(logFileName, FILE_WRITE); // and save it at the end of the file
      if (logFile) {
        Serial.print("writing "); Serial.println(code);
        DateTime now = rtc.now();
        logFile.print(now.year());
        logFile.print('/');
        if (now.month() < 10) logFile.write('0');
        logFile.print(now.month());
        logFile.print('/');
        if (now.day() < 10) logFile.write('0');
        logFile.print(now.day());
        logFile.print("\t");
        logFile.print(now.hour());
        logFile.print(':');
        if (now.minute() < 10) logFile.write('0');
        logFile.print(now.minute());
        logFile.print(':');
        if (now.second() < 10) logFile.write('0');
        logFile.print(now.second());
        logFile.print('\t');
        logFile.println(code);
        logFile.close();
      } else {
        Serial.println("error opening log file for writing!");
      }
      codePos = 0;
    } else {
      if (key != '#' && key != '*') {
        code[codePos++] = key;
        code[codePos] = '\0'; // make it a correct c-string
        if (codePos >= codeLength) codePos = codeLength - 1; // don't overflow
        Serial.println(code);
      }
    }
  }
}

void setup() {
  dumpButton.begin(dumpButtonPin);
  Serial.begin(115200);

  Serial.print("Initializing SD card... ");
  if (!SD.begin(CS_PIN)) {
    Serial.println("Card initialization failed!");
    while (true);
  }
  Serial.println("initialization done.");

  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    Serial.flush();
    abort();
  }

  if (! rtc.isrunning()) {
    Serial.println("RTC is NOT running, let's set the time!");
    // When time needs to be set on a new device, or after a power loss, the
    // following line sets the RTC to the date & time this sketch was compiled
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
    // This line sets the RTC with an explicit date & time, for example to set
    // January 25, 2024 at 2pm you would call:
    // rtc.adjust(DateTime(2024, 1, 25, 14, 0, 0));
  }

  DateTime now = rtc.now();
  Serial.print("Date: ");
  Serial.print(now.year());
  Serial.print('/');
  if (now.month() < 10) Serial.write('0');
  Serial.print(now.month());
  Serial.print('/');
  if (now.day() < 10) Serial.write('0');
  Serial.println(now.day());
  Serial.print("Time: ");
  Serial.print(now.hour());
  Serial.print(':');
  if (now.minute() < 10) Serial.write('0');
  Serial.print(now.minute());
  Serial.print(':');
  if (now.second() < 10) Serial.write('0');
  Serial.println(now.second());
  Serial.println("System ready to log codes.");
}

void loop() {
  // pressing the button dumps the data from the log file
  dumpButton.poll();
  if (dumpButton.onPress())  dumpData();

  // keypad management
  handleKeypad();

}