#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <PinButton.h>
#include <EEPROM.h>

#define SCREEN_WIDTH 128  // OLED display width, in pixels
#define SCREEN_HEIGHT 32  // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
// The pins for I2C are defined by the Wire-library.
// On an arduino UNO:       A4(SDA), A5(SCL)
// On an arduino MEGA 2560: 20(SDA), 21(SCL)
// On an arduino LEONARDO:   2(SDA),  3(SCL), ...
#define OLED_RESET -1        // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C  ///< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Create a new button object, listening on pin 5.
// Note: you can create as many as you like.
PinButton buttonA(11);
PinButton buttonB(12);
const int MOTOR_PIN = 10;

bool bVibrate = false;
int motorState = LOW;

int int_vibrationinterval = 1000;
const int VIBRATE_SHORT = 1000;
const int VIBRATE_LONG = 2000;


unsigned long previousMillis = 0;

enum menu {
  M_START,
  M_SETTINGS,
  M_CREDITS
};
menu currentMenu = M_START;

enum submenu_setting {
  LEFTHAND_MODE,
  SQUARES
};
submenu_setting submenuSettings = SQUARES;
submenu_setting currentSubmenuSettings = SQUARES;

enum submenu_squares {
  SQ_FOUR_SUM,
  SQ_FOUR_BDAY
};
submenu_squares currentSubmenuSquares = SQ_FOUR_SUM;

enum states {
  MENU,
  START,
  SETTINGS,
  LEFTHAND,
  SUB_SQUARES,
  CREDITS,
  SHOW_MS
};

states currentState = START;
states selectedState = MENU;

enum squares {
  FOUR_SUM,
  FOUR_BDAY
};
squares menuSquare = FOUR_SUM;

int squaresize = 4;
bool squareissum = true;

bool leftHandMode = false;

// Initialize variables for the input number
int oneNumber = 5;
int twoNumber = 5;
int threeNumber = 5;
int numberOfDigits = 1;
int activeNumber = 1;
int showLine = 1;


//init variables fpr birthday MS
int day1Value = 1;
int day2Value = 5;
int day1max = 3;
int day1min = 0;
int day2max = 9;
int day2min = 0;
int month1Value = 0;
int month1min = 0;
int month1max = 1;
int month2Value = 5;
int month2min = 0;
int month2max = 9;
int century1Value = 1;
int century1min = 0;
int century1max = 2;
int century2Value = 9;
int century2min = 0;
int century2max = 9;
int year1Value = 5;
int year1min = 0;
int year1max = 9;
int year2Value = 5;
int year2min = 0;
int year2max = 9;


// Initialize variables for the results
int result[16];  // For result1 through result16
int pos1;
int totals;
int ms4sum = 34;

// Array simulating the ms4[] array from the original JavaScript
int ms3[9] = { 8, 1, 6, 3, 5, 7, 4, 9, 2 };  // Adjusted for 3x3
int ms4[16] = { 9, 6, 3, 16, 4, 15, 10, 5, 14, 1, 8, 11, 7, 12, 13, 2 };

// Definiere Sprachen: 0 = Deutsch, 1 = Englisch, 2 = Spanisch, 3 = Französisch
int sprache = 0; // Aktuelle Sprache (Standard: Deutsch)


void doVibration(int duration){
  bVibrate = true;
  int_vibrationinterval = duration;
}

void printOnDisplay(int16_t x, int16_t y, int number) {
  char buf[4];
  itoa(number, buf, 10);
  display.setCursor(x, y);
  display.print(buf);
  Serial.print("printing: ");
  Serial.println(buf);
}
void printOnDisplay(int16_t x, int16_t y, String text) {
  display.setCursor(x, y);
  display.print(text);
}

void showMenu() {
  display.setTextSize(2);  //height=9 pixels, width=5 pixels at textsize 1
  display.clearDisplay();
  switch (selectedState) {
    case MENU:
      switch (currentState) {
        case START:
          display.setCursor(0, 12);
          display.print("START");
          display.display();
          break;

        case SETTINGS:
          display.setCursor(0, 12);
          display.print("SETTINGS");
          display.display();
          break;

        case CREDITS:
          display.setCursor(0, 12);
          display.print("CREDITS");
          display.display();
          break;
      }
      break;
  }
}

void showSettings() {
  display.clearDisplay();
  display.setTextSize(1);
  printOnDisplay(0, 0, "Settings");
  display.setTextSize(2);
  switch (currentSubmenuSettings) {
    case LEFTHAND_MODE:
      if (leftHandMode) {
        display.setRotation(2);  //rotates text on OLED 1=90 degrees, 2=180 degrees
        display.setCursor(0, 12);
        display.print("> Leftymode");
        display.display();
      } else {
        display.setRotation(0);  //rotates text on OLED 1=90 degrees, 2=180 degrees
        display.setCursor(0, 12);
        display.print("Leftymode");
        display.display();
      }
      break;
    case SQUARES:
      printOnDisplay(0, 12, "set Square");
      break;
  }
  display.display();
}

void showSubmenuSquares() {
  display.clearDisplay();
  display.setTextSize(1);
  printOnDisplay(0, 0, "Squares-Settings");
  display.setTextSize(2);
  switch (menuSquare) {
    case FOUR_SUM:
      if (squaresize == 4 && squareissum) {
        printOnDisplay(0, 12, "> 4x4 Sum");
      } else {
        printOnDisplay(0, 12, "4x4 Sum");
      }
      break;
    case FOUR_BDAY:
      if (squaresize == 4 && !squareissum) {
        printOnDisplay(0, 12, "> 4x4 Bday");
      } else {
        printOnDisplay(0, 12, "4x4 Bday");
      }
      break;
  }
  display.display();
}


// Function to validate if input is a number
bool validate(String data) {
  for (int i = 0; i < data.length(); i++) {
    if (!isDigit(data.charAt(i))) {
      return false;
    }
  }
  return true;
}

void setup() {
  Serial.begin(9600);
  if (EEPROM.read(0) == 1) {
    squaresize = EEPROM.read(10);
    squareissum = EEPROM.read(20);
    leftHandMode = EEPROM.read(30);
  } else {
    EEPROM.write(0, 1);
    EEPROM.write(10, squaresize);
    EEPROM.write(20, squareissum);
    EEPROM.write(20, leftHandMode);
  }
  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 begin failed"));
    for (;;)
      ;
  }
  display.clearDisplay();
  display.setTextSize(1);               //height=9 pixels, width=5 pixels at textsize 1
  display.setTextColor(SSD1306_WHITE);  // Draw white text
  Serial.println(F("Los gehts"));
}

void calcMagicSquare() {
  if (squaresize == 4 && squareissum) {
    Serial.println("Calc 4x4 SUM");
    pos1 = oneNumber;
    if (numberOfDigits == 2)
      pos1 = (oneNumber * 10) + twoNumber;
    if (numberOfDigits == 3)
      pos1 = (oneNumber * 100) + (twoNumber * 10) + threeNumber;

    Serial.println(pos1);
    // Perform the calculations as in the original JavaScript code
    int workms4 = pos1 - ms4sum;
    int b = workms4 / squaresize;
    int c = (b + (pos1 - ms4sum)) - (b * squaresize);


    // Calculate the results based on ms4[] array
    result[0] = ms4[0] + b;
    result[1] = ms4[1] + b;
    result[2] = ms4[2] + b;
    result[3] = ms4[3] + c;

    result[4] = ms4[4] + b;
    result[5] = ms4[5] + c;
    result[6] = ms4[6] + b;
    result[7] = ms4[7] + b;

    result[8] = ms4[8] + c;
    result[9] = ms4[9] + b;
    result[10] = ms4[10] + b;
    result[11] = ms4[11] + b;

    result[12] = ms4[12] + b;
    result[13] = ms4[13] + b;
    result[14] = ms4[14] + c;
    result[15] = ms4[15] + b;
  } else if (squaresize == 4 && !squareissum) {
    Serial.println("Calc BDAY");
    int dd = (day1Value * 10) + day2Value;
    int mm = (month1Value * 10) + month2Value;
    int cc = (century1Value * 10) + century2Value;
    int yy = (year1Value * 10) + year2Value;
    Serial.println(dd);
    Serial.println(mm);
    Serial.println(cc);
    Serial.println(yy);

    // Calculate the results based on ms4[] array
    result[0] = dd;
    result[1] = mm;
    result[2] = cc;
    result[3] = yy;
    result[4] = yy + 1;
    result[5] = cc - 1;
    result[6] = mm - 3;
    result[7] = dd + 3;
    result[8] = mm - 2;
    result[9] = dd + 2;
    result[10] = yy + 2;
    result[11] = cc - 2;
    result[12] = cc + 1;
    result[13] = yy - 1;
    result[14] = dd + 1;
    result[15] = mm - 1;
  }
}

void showMSLines(int line) {
  if (squaresize == 4) {
    Serial.println("Magisches Quadrat mit gewünschter Summe:");
    for (int i = 0; i <= 12; i = i + 4) {
      for (int j = 0; j < 4; j++) {
        Serial.print(result[i + j]);
        Serial.print('\t');  // Tabulator für bessere Lesbarkeit
      }
      Serial.println();  // Neue Zeile für jede Reihe
    }
    display.clearDisplay();
    int x = 20;
    int y = 0;
    int i = 0;
    int last = 3;
    if (line == 2) {
      i = 4;
      last = 7;
    } else if (line == 3) {
      i = 8;
      last = 11;
    }
    if (line == 4) {
      i = 12;
      last = 15;
    }
    display.setTextSize(1);
    printOnDisplay(0, 0, "Line");
    printOnDisplay(33, 0, line);
    printOnDisplay(41, 0, ":");
    display.display();

    display.setTextSize(1);
    for (i; i <= last; i++) {
      printOnDisplay(y, x, result[i]);
      display.display();
      y = y + 30;
    }
  }
}



void showMS() {
  Serial.println("Magisches Quadrat mit gewünschter Summe:");
  for (int i = 0; i <= 12; i = i + 4) {
    for (int j = 0; j < 4; j++) {
      Serial.print(result[i + j]);
      Serial.print('\t');  // Tabulator für bessere Lesbarkeit
    }
    Serial.println();  // Neue Zeile für jede Reihe
  }
  display.clearDisplay();
  char buf[4];
  int x = 7;
  int xfactor = 8;
  int rowfactor = 0;
  for (int j = 1; j <= 4; j++) {

    int y = 0;
    for (int i = 0; i < 4; i++) {
      itoa(result[i + rowfactor], buf, 10);
      printOnDisplay(y, x, buf);
      y = y + 20;
    }
    x = x + xfactor;
    rowfactor = rowfactor + 4;
  }
}

void showCredits() {
  display.clearDisplay();
  display.setTextSize(1);
  printOnDisplay(0, 10, "Channing Moos");
  printOnDisplay(0, 20, "Tim Holzhausen");
  display.display();
}

void showInputSum() {
  display.clearDisplay();
  display.setTextSize(1);
  printOnDisplay(0, 0, "Input the Sum");
  display.setTextSize(2);
  Serial.print("Number of Digits: ");
  Serial.println(numberOfDigits);
  if (numberOfDigits == 1) {
    display.drawFastHLine(0, 31, 9, SSD1306_WHITE);
  }
  printOnDisplay(0, 15, oneNumber);
  if (numberOfDigits == 2) {
    Serial.println("nummer2");
    printOnDisplay(30, 15, twoNumber);
    display.drawFastHLine(30, 31, 9, SSD1306_WHITE);
  }
  if (numberOfDigits == 3) {
    Serial.println("nummer3");
    printOnDisplay(30, 15, twoNumber);
    printOnDisplay(60, 15, threeNumber);
    display.drawFastHLine(60, 31, 9, SSD1306_WHITE);
  }
  display.display();
}

void showInputBirthday() {
  display.clearDisplay();
  display.setTextSize(1);
  printOnDisplay(0, 0, "Input the Birthday");
  //Draw line under active number
  if (activeNumber == 1) {
    display.drawFastHLine(0, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 2) {
    display.drawFastHLine(12, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 3) {
    display.drawFastHLine(30, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 4) {
    display.drawFastHLine(42, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 5) {
    display.drawFastHLine(60, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 6) {
    display.drawFastHLine(72, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 7) {
    display.drawFastHLine(84, 31, 9, SSD1306_WHITE);
  } else if (activeNumber == 8) {
    display.drawFastHLine(96, 31, 9, SSD1306_WHITE);
  }
  display.setTextSize(2);
  //DD
  printOnDisplay(0, 15, day1Value);
  printOnDisplay(12, 15, day2Value);
  printOnDisplay(20, 15, ".");
  //MM
  printOnDisplay(30, 15, month1Value);
  printOnDisplay(42, 15, month2Value);
  printOnDisplay(50, 15, ".");
  //CC
  printOnDisplay(60, 15, century1Value);
  printOnDisplay(72, 15, century2Value);

  //YY
  printOnDisplay(84, 15, year1Value);
  printOnDisplay(96, 15, year2Value);

  display.display();
}

void handleBirthdayInputs(bool add) {
  if (add) {
    if (activeNumber == 1) {
      if (day1Value < day1max)
        day1Value++;
      if (day1Value == 3){
        day2Value = 0;
        day2max = 1;
      } else {
        day2max = 9;
      }
    } else if (activeNumber == 2) {
        if (day2Value < day2max)
          day2Value++;
    } else if (activeNumber == 3) {
      if (month1Value < month1max)
        month1Value++;
      if (month1Value == 1) {
        month2Value = 1;
        month2max = 2;
      } else {
        month2max = 9;
      }
    } else if (activeNumber == 4) {
      if (month2Value < month2max)
        month2Value++;
    } else if (activeNumber == 5) {
      if (century1Value < century1max)
        century1Value++;
      if (century1Value == 2) {
        century2Value = 0;
        year1Value = 0;
        year2Value = 0;
      }
    } else if (activeNumber == 6) {
      if (century2Value < century2max)
        century2Value++;
    } else if (activeNumber == 7) {
      if (year1Value < year1max)
        year1Value++;
    } else if (activeNumber == 8) {
      if (year2Value < year2max)
        year2Value++;
    }
  } else {
    if (activeNumber == 1) {
      if (day1Value > day1min)
        day1Value--;
      if (day1Value == 3){
        day2Value = 0;
        day2max = 1;
      } else {
        day2max = 9;
      }
    } else if (activeNumber == 2) {
      if (day2Value > day2min)
        day2Value--;
    } else if (activeNumber == 3) {
      if (month1Value > month1min)
        month1Value--;
      if (month1Value == 1) {
        month2Value = 1;
        month2max = 2;
      } else {
        month2max = 9;
      }
    } else if (activeNumber == 4) {
      if (month2Value > month2min)
        month2Value--;
    } else if (activeNumber == 5) {
      if (century1Value > century1min)
        century1Value--;
      if (century1Value == 2) {
        century2Value = 0;
        year1Value = 0;
        year2Value = 0;
      }
    } else if (activeNumber == 6) {
      if (century2Value > century2min)
        century2Value--;
    } else if (activeNumber == 7) {
      if (year1Value > year1min)
        year1Value--;
    } else if (activeNumber == 8) {
      if (year2Value > year2min)
        year2Value--;
    }
  }
}


void handlePrimarySingleClick() {
  Serial.println("primary single");
  switch (selectedState) {
    case SHOW_MS:
      if (showLine > 1) {
        showLine--;
        showMSLines(showLine);
      }
      break;
    case SETTINGS:
      switch (currentSubmenuSettings) {
        case LEFTHAND_MODE:
          if (!leftHandMode)
            leftHandMode = true;
          else
            leftHandMode = false;
          EEPROM.write(30, leftHandMode);
          showSettings();
          break;
        case SQUARES:
          selectedState = SUB_SQUARES;
          showSubmenuSquares();
          break;
      }
      break;
    case SUB_SQUARES:
      switch (menuSquare) {
        case FOUR_SUM:
          squaresize = 4;
          squareissum = true;
          break;
        case FOUR_BDAY:
          squaresize = 4;
          squareissum = false;
          break;
      }
      EEPROM.write(10, squaresize);
      EEPROM.write(20, squareissum);
      showSubmenuSquares();
      break;

    case MENU:
      switch (currentState) {
        case START:
          selectedState = START;
          if (squareissum)
            showInputSum();
          else
            showInputBirthday();
          break;
        case SETTINGS:
          selectedState = SETTINGS;
          display.clearDisplay();
          showSettings();
          break;
        case CREDITS:
          selectedState = CREDITS;
          showCredits();
          break;
      }
      break;
    case START:
      if (squareissum) {
        if (activeNumber == 1 && oneNumber > 0)
          oneNumber = oneNumber - 1;
        if (activeNumber == 2 && twoNumber > 0)
          twoNumber = twoNumber - 1;
        if (activeNumber == 3 && threeNumber > 0)
          threeNumber = threeNumber - 1;
        showInputSum();
      } else {
        handleBirthdayInputs(false);
        showInputBirthday();
      }
      break;
  }
}

void handlePrimaryLongClick() {
  Serial.println("A long");
  Serial.print("activeNumber: ");
  Serial.println(activeNumber);
  Serial.print("selectedState");
  Serial.println(selectedState);

  display.clearDisplay();

  switch (selectedState) {
    case SHOW_MS:
      showLine = 1;
      selectedState = START;
      if (squareissum) {
        showInputSum();
      } else {
        showInputBirthday();
      }

      break;
    case START:
      if (activeNumber == 1) {
        Serial.println("Switching to Menu");
        selectedState = MENU;
        display.clearDisplay();
        showMenu();
        oneNumber = 5;
      } else {
        if (squareissum) {
          numberOfDigits--;
          activeNumber--;
          showInputSum();
        } else {
          activeNumber--;
          showInputBirthday();
        }
      }

      break;
    case CREDITS:
    case SETTINGS:
      selectedState = MENU;
      Serial.println("going back to MENU");
      break;
    case SUB_SQUARES:
      selectedState = SETTINGS;
      Serial.println("going back to SETTINGS");
      showSettings();
      break;
  }
}
void handlePrimaryDoubleClick() {
  Serial.println("A double");
}
void handleSecondarySingleClick() {
  display.clearDisplay();
  Serial.println("secondary single");
  switch (selectedState) {
    case SHOW_MS:
      if (showLine < squaresize) {
        showLine++;
        showMSLines(showLine);
      } else {
        showMSLines(showLine);
      }
      break;
    case MENU:
      switch (currentState) {
        case START:
          currentState = SETTINGS;
          break;

        case SETTINGS:
          currentState = CREDITS;
          break;

        case CREDITS:
          currentState = START;
          break;
      }
      break;
    case SETTINGS:
      switch (currentSubmenuSettings) {
        case LEFTHAND_MODE:
          currentSubmenuSettings = SQUARES;
          break;

        case SQUARES:
          currentSubmenuSettings = LEFTHAND_MODE;
          break;
      }
      showSettings();
      break;


    case SUB_SQUARES:
      switch (menuSquare) {
        case FOUR_SUM:
          menuSquare = FOUR_BDAY;
          showSubmenuSquares();
          break;

        case FOUR_BDAY:
          menuSquare = FOUR_SUM;
          showSubmenuSquares();
          break;
      }
      break;
    case START:
      if (squareissum) {
        if (activeNumber == 1 && oneNumber < 9)
          oneNumber = oneNumber + 1;
        if (activeNumber == 2 && twoNumber < 9)
          twoNumber = twoNumber + 1;
        if (activeNumber == 3 && threeNumber < 9)
          threeNumber = threeNumber + 1;
        showInputSum();
      } else {
        handleBirthdayInputs(true);
        showInputBirthday();
      }
      break;
  }
}

void handleSecondaryDoubleClick() {
  Serial.println("B double");
  switch (selectedState) {
    case START:
      calcMagicSquare();
      showMSLines(showLine);
      selectedState = SHOW_MS;
      break;
  }
}
void handleSecondaryLongClick() {
  Serial.println("B long");
  switch (selectedState) {
    case START:
      if (squareissum) {
        if (numberOfDigits < 3) {
          numberOfDigits++;
          activeNumber++;
        }
        showInputSum();
      } else {
        if (activeNumber != 8)
          activeNumber++;
        showInputBirthday();
      }
      break;
  }
}


void handleClicks() {
  // Read hardware pin, convert to click events
  buttonA.update();
  buttonB.update();

  // Print a message for each type of click.
  // Note that "click" is also generated for the
  // first click of a double-click, but "single"
  // is only generated if it definitely is not
  // going to be a double click.
  if (buttonA.isSingleClick()) {
    Serial.println("A single");
    doVibration(VIBRATE_SHORT);
    if (!leftHandMode)
      handlePrimarySingleClick();
    else
      handleSecondarySingleClick();
  }
  if (buttonA.isDoubleClick()) {
    doVibration(VIBRATE_SHORT);
    if (!leftHandMode)
      handlePrimaryDoubleClick();
    else
      handleSecondaryDoubleClick();
  }
  if (buttonA.isLongClick()) {
    doVibration(VIBRATE_LONG);
    if (!leftHandMode)
      handlePrimaryLongClick();
    else
      handleSecondaryLongClick();
  }
  if (buttonB.isSingleClick()) {
    doVibration(VIBRATE_SHORT);
    Serial.println("B single");
    if (!leftHandMode)
      handleSecondarySingleClick();
    else
      handlePrimarySingleClick();
  }
  if (buttonB.isDoubleClick()) {
    doVibration(VIBRATE_SHORT);
    if (!leftHandMode)
      handleSecondaryDoubleClick();
    else
      handlePrimaryDoubleClick();
  }
  if (buttonB.isLongClick()) {
    doVibration(VIBRATE_LONG);
    if (!leftHandMode)
      handleSecondaryLongClick();
    else
      handlePrimaryLongClick();
  }
}



void loop() {
  //Handle LeftHandMode
  if (leftHandMode) {
    display.setRotation(2);  //rotates text on OLED 1=90 degrees, 2=180 degrees

  } else {
    display.setRotation(0);  //rotates text on OLED 1=90 degrees, 2=180 degrees
  }
  // listen to buttons
  handleClicks();
  showMenu();
  unsigned long currentMillis = millis();

  if (bVibrate){
    // save the time the vibration started
    if (motorState != HIGH){
      previousMillis = currentMillis;
      Serial.println("starting vibration");
    }
    motorState = HIGH;
    digitalWrite(MOTOR_PIN, motorState);
    
    
  }

  if (currentMillis - previousMillis >= int_vibrationinterval && motorState == HIGH ) {
    Serial.println("stoping vibration");
    // set the boolean back to false
    bVibrate = false;
    motorState = LOW;
    // turn off the vibration
    digitalWrite(MOTOR_PIN, LOW);
  }
}