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

RTC_DS3231 rtc;
bool rtcAvailable = true;

// --- SD Card ---
#define SD_CS_PIN 5
File logFile;
bool sdAvailable = false;

// --- Daftar Menu dan Pin Tombol ---
const int NUM_BUTTONS = 11;
const int buttonPins[NUM_BUTTONS] = {
  13, 12, 14, 27, 26, 25, 35, 34,
  15, 2, 4
};
const char* itemNames[NUM_BUTTONS] = {
  "GULA", "TEPUNG GULA", "PEDAS", "SUSU PUTIH", "SUSU COKLAT",
  "KEJU SUSU", "KACANG SUSU", "CHOCOLATE", "MESES SUSU", "OREO SUSU",
  "COKELAT KACANG SUSU"
};
bool lastState[NUM_BUTTONS];
unsigned long lastDebounce[NUM_BUTTONS];
const unsigned long debounceDelay = 200;

// --- Tombol kontrol ---
const int cancelButtonPin = 33;
bool lastCancelState = HIGH;
unsigned long lastCancelDebounce = 0;

const int finishButtonPin = 32;
bool lastFinishState = HIGH;
unsigned long lastFinishDebounce = 0;

// --- Penyimpanan pesanan ---
const int MAX_ORDERS = 100;
String orderHistory[MAX_ORDERS];
int orderCount = 0;

void setup() {
  Serial.begin(115200);
  Wire.begin();

  // RTC
  if (!rtc.begin()) {
    Serial.println("⚠️ RTC tidak ditemukan. Melanjutkan tanpa RTC.");
    rtcAvailable = false;
  } else if (rtc.lostPower()) {
    Serial.println("RTC kehilangan daya. Mengatur ulang waktu.");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  // SD
  if (SD.begin(SD_CS_PIN)) {
    sdAvailable = true;
    Serial.println("✅ SD Card siap.");
  } else {
    Serial.println("⚠️ SD Card gagal dibaca.");
  }

  // Tombol menu
  for (int i = 0; i < NUM_BUTTONS; i++) {
    pinMode(buttonPins[i], INPUT_PULLUP);
    lastState[i] = digitalRead(buttonPins[i]);
    lastDebounce[i] = 0;
  }

  // Tombol kontrol
  pinMode(cancelButtonPin, INPUT_PULLUP);
  lastCancelState = digitalRead(cancelButtonPin);
  pinMode(finishButtonPin, INPUT_PULLUP);
  lastFinishState = digitalRead(finishButtonPin);

  Serial.println("✅ Sistem pencatatan topping siap!");
}

void loop() {
  // Cek tombol topping
  for (int i = 0; i < NUM_BUTTONS; i++) {
    int currentState = digitalRead(buttonPins[i]);
    if (lastState[i] == HIGH && currentState == LOW) {
      if (millis() - lastDebounce[i] > debounceDelay) {
        logOrder(itemNames[i]);
        lastDebounce[i] = millis();
      }
    }
    lastState[i] = currentState;
  }

  // Cancel
  int cancelState = digitalRead(cancelButtonPin);
  if (lastCancelState == HIGH && cancelState == LOW) {
    if (millis() - lastCancelDebounce > debounceDelay) {
      cancelLastOrder();
      lastCancelDebounce = millis();
    }
  }
  lastCancelState = cancelState;

  // Selesai
  int finishState = digitalRead(finishButtonPin);
  if (lastFinishState == HIGH && finishState == LOW) {
    if (millis() - lastFinishDebounce > debounceDelay) {
      showFinalOrder();
      lastFinishDebounce = millis();
    }
  }
  lastFinishState = finishState;
}

void logOrder(const char* item) {
  if (orderCount < MAX_ORDERS) {
    orderHistory[orderCount] = item;
    orderCount++;
    Serial.print("Pesanan dicatat: ");
    Serial.println(item);
  } else {
    Serial.println("❌ Memori penuh.");
  }
}

void cancelLastOrder() {
  if (orderCount > 0) {
    orderCount--;
    Serial.print("Pesanan dibatalkan: ");
    Serial.println(orderHistory[orderCount]);
    orderHistory[orderCount] = "";
  } else {
    Serial.println("Tidak ada pesanan.");
  }
}

void showFinalOrder() {
  Serial.println("\n=== PESANAN SELESAI ===");

  String timeStamp = "";
  if (rtcAvailable) {
    DateTime now = rtc.now();
    char buffer[30];
    sprintf(buffer, "%04d-%02d-%02d %02d:%02d:%02d",
            now.year(), now.month(), now.day(),
            now.hour(), now.minute(), now.second());
    timeStamp = String(buffer);
    Serial.print("Waktu: ");
    Serial.println(timeStamp);
  } else {
    timeStamp = "[Waktu tidak tersedia]";
  }

  if (orderCount == 0) {
    Serial.println("Tidak ada pesanan.");
    return;
  }

  int itemCounts[NUM_BUTTONS] = {0};
  for (int i = 0; i < orderCount; i++) {
    for (int j = 0; j < NUM_BUTTONS; j++) {
      if (orderHistory[i] == itemNames[j]) {
        itemCounts[j]++;
      }
    }
  }

  int total = 0;
  String output = timeStamp + ", Pesanan: ";

  for (int j = 0; j < NUM_BUTTONS; j++) {
    if (itemCounts[j] > 0) {
      Serial.print(itemNames[j]);
      Serial.print(": ");
      Serial.println(itemCounts[j]);
      output += String(itemCounts[j]) + "x " + itemNames[j] + ", ";
      total += itemCounts[j];
    }
  }

  Serial.print("TOTAL ITEM: ");
  Serial.println(total);
  output += "TOTAL: " + String(total);

  // Simpan ke SD Card
  if (sdAvailable) {
    logFile = SD.open("pesanan.txt", FILE_APPEND);
    if (logFile) {
      logFile.println(output);
      logFile.close();
      Serial.println("✅ Pesanan disimpan di SD Card.");
    } else {
      Serial.println("❌ Gagal menulis ke SD Card.");
    }
  }

  Serial.println("========================\n");

  // Reset
  for (int i = 0; i < orderCount; i++) orderHistory[i] = "";
  orderCount = 0;
}