/**
   Arduino Calculator

   Copyright (C) 2020, Uri Shaked.
   Released under the MIT License.
*/// include the library code:
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);

#include <Keypad.h> 

/* Keypad setup */
const byte KEYPAD_ROWS = 4;
const byte KEYPAD_COLS = 4;
byte rowPins[KEYPAD_ROWS] = {5, 4, 3, 2};
byte colPins[KEYPAD_COLS] = {A3, A2, A1, A0};
char keys[KEYPAD_ROWS][KEYPAD_COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, KEYPAD_ROWS, KEYPAD_COLS);

boolean flag_state = true;
int domestic_stamp = 1000;
int zone1_stamp = 1000;
int zone2_stamp = 1000;

float domestic_price = 0.50;
float zone1_price = 1.50;
float zone2_price = 2.00;

bool main_disp = false;
bool sel_domestic = false;
bool sel_inter = false;

int qty = 0;
String qty_str = "";

String is_selected = "";
bool disp_internationl = false;
void setup() {
  Serial.begin(115200); 
  lcd.init();
  lcd.backlight(); 
}



void loop() {
  if (main_disp == false)
  {
    char key = keypad.getKey();
    MainDisplay();
    switch (key)
    {
      case 'A':
        lcd.clear();
        sel_domestic = true;
        main_disp = true;
        break;
      case 'B':
        lcd.clear();
        sel_inter = true;
        main_disp = true;
        break;
      case '#':
        main_disp = true;
        remainingStamp();
        main_disp = false;
        break;
      default:

        break;
    }
  }

  while (sel_domestic == true)
  {
    char key = keypad.getKey();
    SelectDomestic();
    switch (key )
    {
      case '*':
        lcd.clear();
        qty_str = "";
        qty = 0;
        main_disp = false;
        sel_domestic = false;
        break;
      case '#':
        sel_domestic = false;
        lcd.clear();
        domestic_stamp = domestic_stamp - qty;
        WholeAmount(domestic_price);
        delay(5000);
        qty_str = "";
        qty = 0;
        lcd.clear();
        main_disp = false;
        break;
      default:
        if ((key != 'A') && (key != 'B') && (key != 'C') && (key != 'D') && (qty <= domestic_stamp))
        {
          qty_str += String(key);
          qty = qty_str.toDouble();
          Serial.println(qty);
          lcd.setCursor(5, 1);
          lcd.print(qty_str);
        }
        else
        {
          lcd.clear();
          qty_str = "";
          qty = 0;
          lcd.setCursor(5, 1);
          lcd.print(qty);
        }
        break;
    }
  }

  while (sel_inter == true)
  {
    char key = keypad.getKey();
    if (disp_internationl == false)
    {
      SelectInternational();
    }

    switch (key )
    {
      case '*':
        lcd.clear();
        qty_str = "";
        qty = 0;
        is_selected = "";
        disp_internationl = false;
        main_disp = false;
        sel_inter = false;
        break;
      case '#':
        if (is_selected != "")
        {
          if (qty > 0)
          {
            lcd.clear();
            if ( is_selected == "A.Zone 1 Intl")
            {
              zone1_stamp = zone1_stamp - qty;
              WholeAmount(zone1_price);
            }
            else
            {
              zone2_stamp = zone2_stamp - qty;
              WholeAmount(zone2_price);
            }
            delay(5000);
            main_disp = false;
            sel_inter = false;
            qty_str = "";
            qty = 0;
            disp_internationl = false;
            is_selected = "";
          }
          else
          {
            disp_internationl = true;
            lcd.clear();
            Sel_International(is_selected);
          }
        }
        // else
        // {
        //   disp_internationl = false;
        //   qty_str = "";
        //   qty = 0;
        // }
        break;
      case 'A':
        if (disp_internationl == false)
        {
          is_selected = "A.Zone 1 Intl";
          lcd.setCursor(14, 0);
          lcd.print("*"  );
          lcd.setCursor(14, 1);
          lcd.print(" "  );
        }
        break;
      case 'B':
        if (disp_internationl == false)
        {
          is_selected = "B.Zone 2 Intl";
          lcd.setCursor(14, 0);
          lcd.print(" "  );
          lcd.setCursor(14, 1);
          lcd.print("*"  );
        }
        break;
      default:
        if (disp_internationl == true )
        {
          if ( is_selected == "A.Zone 1 Intl")
          {
            if ((key != 'A') && (key != 'B') && (key != 'C') && (key != 'D') && (qty < zone1_stamp))
            {
              qty_str += String(key);
              qty = qty_str.toInt();
              Serial.println(qty);
              lcd.setCursor(5, 1);
              lcd.print(qty_str);
            }
            else
            {
              lcd.clear();
              Sel_International(is_selected);
              qty_str = "";
              qty = 0;
              lcd.setCursor(5, 1);
              lcd.print(qty);
            }
          }
          else
          {
            if ((key != 'A') && (key != 'B') && (key != 'C') && (key != 'D') && (qty < zone2_stamp))
            {
              qty_str += String(key);
              qty = qty_str.toInt();
              Serial.println(qty);
              lcd.setCursor(5, 1);
              lcd.print(qty_str);
            }
            else
            {
              lcd.clear();
              Sel_International(is_selected);
              qty_str = "";
              qty = 0;
              lcd.setCursor(5, 1);
              lcd.print(qty);
            }
          }

        }
    }
  }
}

void MainDisplay()
{
  lcd.setCursor(0, 0);
  lcd.print("A. Domestic");
  lcd.setCursor(0, 1);
  lcd.print("B. International");
}
void SelectDomestic()
{
  lcd.setCursor(0, 0);
  lcd.print("Domestic:$" + String(domestic_price));
  lcd.setCursor(0, 1);
  lcd.print("QTY.:");
}

void Sel_International(String msg)
{
  lcd.setCursor(0, 0);
  lcd.print(msg);
  lcd.setCursor(0, 1);
  lcd.print("QTY.:");
}


void SelectInternational()
{
  lcd.setCursor(0, 0);
  lcd.print("A.Zone 1 Intl"  );
  lcd.setCursor(0, 1);
  lcd.print("B.Zone 2 Intl"  );
}


void WholeAmount(float price)
{
  lcd.setCursor(0, 0);
  lcd.print("  Whole Amount  ");
  lcd.setCursor(0, 1);
  lcd.print("Amount: $" + String(qty * price));

  qty_str = "";
  qty = 0;
}

void remainingStamp()
{
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Remaining Stamp ");
  lcd.setCursor(0, 1);
  lcd.print("Domestic:" + String(domestic_stamp));
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Z1 Intl.:" + String(zone1_stamp));
  lcd.setCursor(0, 1);
  lcd.print("Z2 Intl.:" + String(zone2_stamp));
  delay(2000);
  lcd.clear();

}