#include <Arduino.h>
#include <EEPROM.h>
#include <LiquidCrystal_I2C.h>
#include <Adafruit_Thermal.h>

enum DeviceState {
  READY,
  PRINTING
};

DeviceState state = READY;  // Declare the 'state' variable here

LiquidCrystal_I2C lcd(0x27, 20, 4);
Adafruit_Thermal printer(&Serial);

const int coinPin = 2; // Coin acceptor input
const int vendButtonPin = 3; // Vending button input
const int voucherButtons[] = {4, 5, 6, 7}; // Pins for the 4 voucher buttons

const int voucherRates[] = {5, 10, 15, 20}; // Rates for 30m, 1h, 1.5h, 2h vouchers
const int voucherInventoryAddresses[] = {0, 1, 2, 3}; // EEPROM addresses for inventory

int selectedVoucher = -1; // To track the selected voucher type
int coinsInserted = 0; // To track the coins inserted
int buttonPressed;

String vouchers30min[] = {
  "621444", "266543", "655231", /* Add your 30-min voucher codes here */
};

String vouchers1hour[] = {
  "561223", "551363", "312253", /* Add your 1-hour voucher codes here */
};

String vouchers1h30min[] = {
  "546534", "622656", "344535", /* Add your 1h30min voucher codes here */
};

String vouchers2hours[] = {
  "446156", "611426", "541362", /* Add your 2-hour voucher codes here */
};

String usedVouchers30min[100];
String usedVouchers1hour[100];
String usedVouchers1h30min[100];
String usedVouchers2hours[100];
int usedVoucherCount30min = 0;
int usedVoucherCount1hour = 0;
int usedVoucherCount1h30min = 0;
int usedVoucherCount2hours = 0;

void setup() {
  Serial.begin(19200);
  printer.begin();

  lcd.init();
  lcd.backlight();
  lcd.clear(); // Clear the LCD display

  for (int i = 0; i < 4; i++) {
    pinMode(voucherButtons[i], INPUT_PULLUP);
  }
  pinMode(vendButtonPin, INPUT_PULLUP);
  pinMode(coinPin, INPUT_PULLUP);

  state = READY; // Set the state to READY after initialization

  lcd.setCursor(0, 0);
  lcd.print(" WIFI VOUCHER VENDO");

  // Initialize the inventory values in EEPROM
  int initialInventory[] = {100, 100, 100, 100}; // Initialize the last type to 100
  for (int i = 0; i < 4; i++) {
    EEPROM.write(voucherInventoryAddresses[i], initialInventory[i]);
  }

  // Read inventory from EEPROM and display it
  int inventory[4];
  for (int i = 0; i < 4; i++) {
    inventory[i] = EEPROM.read(voucherInventoryAddresses[i]);
  }

  // Display inventory on LCD
  lcd.setCursor(0, 1);
  lcd.print("Tm: 30m 1H 1.3H 2H");
  lcd.setCursor(0, 2);
  lcd.print("Rt: ");
  for (int i = 0; i < 4; i++) {
    lcd.print("P");
    lcd.print(voucherRates[i]);
    lcd.print(" ");
  }
  lcd.setCursor(0, 3);
  lcd.print("It: ");
  for (int i = 0; i < 4; i++) {
    lcd.print(inventory[i]);
    lcd.print(" ");
  }
}

void loop() {
  if (state == READY) {
    checkButtons();
    checkCoinAcceptor();
  } else if (state == PRINTING) {
    printVoucher();
  }
}

// Rest of the code remains the same

void checkButtons() {
  for (int i = 0; i < 4; i++) {
    if (digitalRead(voucherButtons[i]) == LOW) {
      buttonPressed = 1;
      selectedVoucher = i;
      lcd.clear();
      delay(1000);
      lcd.setCursor(0, 0);
      lcd.print(" WIFI VOUCHER VENDO");
      lcd.setCursor(0, 1);
      lcd.print("====================");
      lcd.setCursor(0, 2);
      lcd.print("You've selected  ");
      lcd.print(voucherRates[i]);
      lcd.print("P");
      lcd.setCursor(0, 3);
      lcd.print("Please Insert Coins");
      delay(1000); // Delay for button debounce
      state = READY; // Change the state to READY
    }
  }
}

void checkCoinAcceptor() {
  if (digitalRead(coinPin) == LOW) {
    coinsInserted += 1;
    lcd.setCursor(0, 3);
    lcd.print("Coins Inserted:  P");
    lcd.print(coinsInserted);
    delay(100);
  }
if(buttonPressed == 1){
  if (digitalRead(vendButtonPin) == LOW) {
    if (coinsInserted >= voucherRates[selectedVoucher]) {
      printVoucher();
      removeUsedVoucherCode(selectedVoucher);
    } else {
      lcd.setCursor(0, 1);
      lcd.print("INSUFFICIENT  COINS!");
      delay(300);
      lcd.setCursor(0, 1);
      lcd.print("====================");
      delay(300);
      lcd.setCursor(0, 1);
      lcd.print("INSUFFICIENT  COINS!");
      delay(300);
      lcd.setCursor(0, 1);
      lcd.print("====================");
      delay(300);
      state = READY;
      }
    }
  }
}

void printVoucher() {
  lcd.clear(); // Clear the LCD before printing
  lcd.setCursor(0, 0);
  lcd.print("Voucher is Printing");
  lcd.setCursor(0, 2);
  lcd.print("Please wait.");
  delay(250);
  lcd.setCursor(0, 2);
  lcd.print("Please wait..");
  delay(250);
  lcd.setCursor(0, 2);
  lcd.print("Please wait...");
  delay(250);
  lcd.clear(); // Clear the LCD before printing
  lcd.setCursor(0, 0);
  lcd.print("Voucher is Printing");
  lcd.setCursor(0, 2);
  lcd.print("Please wait.");
  delay(250);
  lcd.setCursor(0, 2);
  lcd.print("Please wait..");
  delay(250);
  lcd.setCursor(0, 2);
  lcd.print("Please wait...");

  printer.setDefault(); // Reset printer formatting
  printer.setSize('L'); // Set larger font size
  printer.boldOn();
  printer.println("WIFI VOUCHER VENDO");
  printer.boldOff();
  printer.println();

  // Generate and print the voucher code here
  String voucherCode = generateVoucherCode(selectedVoucher);
  printer.boldOn();
  printer.println(voucherCode);
  printer.boldOff();

  printer.boldOn();
  printer.println("How to use:");
  printer.boldOff();
  printer.println("Open your WiFi");
  printer.println("Tap 'WiFi Voucher' SSID");
  printer.println("Input the voucher Code");
  printer.println("Connect");
  printer.println();
  printer.println("Enjoy!");

  printer.feed(3); // Advance paper
  printer.sleep(); // Put the printer to sleep to cut the paper (if supported)
  delay(3000); // Delay for the cutting process

  // Update inventory and reset selectedVoucher and coinsInserted
  int selectedInventory = EEPROM.read(voucherInventoryAddresses[selectedVoucher]);
  selectedInventory--;
  EEPROM.write(voucherInventoryAddresses[selectedVoucher], selectedInventory);
  selectedVoucher = -1;
  coinsInserted = 0;

  // Set the LCD back to the main display
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("WIFI VOUCHER VENDO");

  int inventory[4];
  for (int i = 0; i < 4; i++) {
    inventory[i] = EEPROM.read(voucherInventoryAddresses[i]);
  }

  lcd.setCursor(0, 1);
  lcd.print("Tm: 30m 1H 1.3H 2H");
  lcd.setCursor(0, 2);
  lcd.print("Rt: ");
  for (int i = 0; i < 4; i++) {
    lcd.print("P");
    lcd.print(voucherRates[i]);
    lcd.print(" ");
  }
  lcd.setCursor(0, 3);
  lcd.print("It: ");
  for (int i = 0; i < 4; i++) {
    lcd.print(inventory[i]);
    lcd.print(" ");
  }

  state = READY; // Change the state back to READY for user interaction
}

String generateVoucherCode(int voucherType) {
  // Generate a voucher code based on the selected voucher type
  String code;
  switch (voucherType) {
    case 0: // 30 minutes
      code = "Voucher-30m-" + String(random(1000, 10000));
      break;
    case 1: // 1 hour
      code = "Voucher-1H-" + String(random(1000, 10000));
      break;
    case 2: // 1.5 hours
      code = "Voucher-1.5H-" + String(random(1000, 10000));
      break;
    case 3: // 2 hours
      code = "Voucher-2H-" + String(random(1000, 10000));
      break;
    default:
      code = "Invalid Voucher";
      break;
  }
  return code;
}

void removeUsedVoucherCode(int voucherType) {
  switch (voucherType) {
    case 0: // 30 minutes
      if (usedVoucherCount30min < 100) {
        usedVouchers30min[usedVoucherCount30min++] = vouchers30min[0];
        for (int i = 0; i < usedVoucherCount30min; i++) {
          vouchers30min[i] = vouchers30min[i + 1];
        }
        usedVouchers30min[usedVoucherCount30min] = "";
      }
      break;
    case 1: // 1 hour
      if (usedVoucherCount1hour < 100) {
        usedVouchers1hour[usedVoucherCount1hour++] = vouchers1hour[0];
        for (int i = 0; i < usedVoucherCount1hour; i++) {
          vouchers1hour[i] = vouchers1hour[i + 1];
        }
        usedVouchers1hour[usedVoucherCount1hour] = "";
      }
      break;
    case 2: // 1.5 hours
      if (usedVoucherCount1h30min < 100) {
        usedVouchers1h30min[usedVoucherCount1h30min++] = vouchers1h30min[0];
        for (int i = 0; i < usedVoucherCount1h30min; i++) {
          vouchers1h30min[i] = vouchers1h30min[i + 1];
        }
        usedVouchers1h30min[usedVoucherCount1h30min] = "";
      }
      break;
    case 3: // 2 hours
      if (usedVoucherCount2hours < 100) {
        usedVouchers2hours[usedVoucherCount2hours++] = vouchers2hours[0];
        for (int i = 0; i < usedVoucherCount2hours; i++) {
          vouchers2hours[i] = vouchers2hours[i + 1];
        }
        usedVouchers2hours[usedVoucherCount2hours] = "";
      }
      break;
  }
}