#include <Wire.h>
#include <Encoder.h>
#include <Servo.h>
#include <U8glib.h>
#include <HX711.h>  
#include <EEPROM.h>


U8GLIB_SSD1306_128X64 Oled(U8G_I2C_OPT_NONE);

Encoder encoder(9, 8);

Servo myservo;

const int buttonPin = 5;
bool test = true;

const int LOADCELL_DOUT_PIN = 7;  
const int LOADCELL_SCK_PIN = 6;
HX711 scale;  
float CALIBRATION_FACTOR;

const int EEPROM_ADDR = 0;
const int EEPROM_M = 4;
const int EEPROM_S = 8;
const int EEPROM_V = 12;

const char* mainItems[] = {
  "Kalibracia", 
  "Plnenie", 
  "Vaha", 
  "Nastavenia",
};

const char* menuItems[] = {
  "Maly pohar", 
  "Stredny pohar", 
  "Velky pohar",
  "Menu"
};

float hmotnostM;
float hmotnostS;
float hmotnostV;

const int mainLength = sizeof(mainItems) / sizeof(mainItems[0]);
const int menuLength = sizeof(menuItems) / sizeof(menuItems[0]);
const int settingsLength = sizeof(menuItems) / sizeof(menuItems[0]);

int menuIndex = 0;
int menuIndex2 = 0;
int settings = 0;
int displayOffset = 0; 
int displayOffset2 = 0;  
const int maxVisibleItems = 3;  
long lastEncoderPos = encoder.read() / 2;
const int threshold = 2; 
bool inSubmenu = false;  
bool inSubmenu2 = false;
bool inSubmenu3 = false;
bool inSubmenu4 = false;
bool zmena = true;
bool zmena2 = false;

void setup() {
  pinMode(buttonPin, INPUT_PULLUP);
  displayMain();
  myservo.attach(3);
  myservo.write(0);

  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);

  EEPROM.get(EEPROM_ADDR, CALIBRATION_FACTOR);
  if (isnan(CALIBRATION_FACTOR)) {
    CALIBRATION_FACTOR = 403.95; 
  }
  EEPROM.get(EEPROM_M, hmotnostM);
  if (isnan(hmotnostM)) {
    hmotnostM = 2000; 
  }
  EEPROM.get(EEPROM_S, hmotnostS);
  if (isnan(hmotnostS)) {
    hmotnostS = 3500; 
  }
  EEPROM.get(EEPROM_V, hmotnostV);
  if (isnan(hmotnostV)) {
    hmotnostV = 5000; 
  }
  scale.set_scale(CALIBRATION_FACTOR);   
  scale.tare();                         

  Serial.begin(9600);
}

void loop() {
  long newPos = encoder.read() / 2;

  unsigned long currentMillis = millis();

  const int debounceDelay = 50; 

  if (abs(newPos - lastEncoderPos) >= threshold) {
    if (!inSubmenu) {
      if (newPos > lastEncoderPos) {
        menuIndex++;
      } else if (newPos < lastEncoderPos) {
        menuIndex--;
      }

      if (menuIndex < 0) {
        menuIndex = 0;
      } else if (menuIndex >= mainLength) {
        menuIndex = mainLength - 1;
      }

      if (menuIndex >= displayOffset + maxVisibleItems) {
        displayOffset = menuIndex - maxVisibleItems + 1;
      } else if (menuIndex < displayOffset) {
        displayOffset = menuIndex;
      }

      displayMain();
    } else {
      if (newPos > lastEncoderPos) {
        menuIndex2++;
      } else if (newPos < lastEncoderPos) {
        menuIndex2--;
      }

      if (menuIndex2 < 0) {
        menuIndex2 = 0;
      } else if (menuIndex2 >= menuLength) {
        menuIndex2 = menuLength - 1;
      }

      if (menuIndex2 >= displayOffset2 + maxVisibleItems) {
        displayOffset2 = menuIndex2 - maxVisibleItems + 1;
      } else if (menuIndex2 < displayOffset2) {
        displayOffset2 = menuIndex2;
      }

      displayMenu();
    }

    lastEncoderPos = newPos;
  }

  if (digitalRead(buttonPin) == LOW && menuIndex == 1 && !inSubmenu) {
    inSubmenu = true;
    displayMenu();
    delay(200); 
  } else if (digitalRead(buttonPin) == LOW && menuIndex == 0 && !inSubmenu2) {
    inSubmenu2 = true;
    kalibracia();
    delay(200); 
  } else if (digitalRead(buttonPin) == LOW && menuIndex == 2 && !inSubmenu3) {
    inSubmenu3 = true;
    vaha();
    delay(200); 
  } 
  else if (digitalRead(buttonPin) == LOW && menuIndex == 3 && !inSubmenu4) {
    inSubmenu4 = true;
    nastavenia();
    delay(200); 
  } 

  if (digitalRead(buttonPin) == LOW && inSubmenu) {
    int i = scale.get_units(); 
    if (digitalRead(buttonPin) == LOW && test == true && i < 20) {
      test = false;

      if (menuIndex2 != 3) {
        Oled.firstPage();
        do {
          Oled.setFont(u8g_font_6x12);
          Oled.drawStr(2, 10, "Polozte nadobu");
          Oled.drawStr(2, 20, "na vahu a stlacte");
          Oled.drawStr(2, 30, "tlacidlo.");
        } while (Oled.nextPage());

        delay(100);
        while(digitalRead(buttonPin) == HIGH) {
        }
        scale.tare(); 
        if (menuIndex2 == 0) {  
          plnenie(hmotnostM);
        } else if (menuIndex2 == 1) {  
          plnenie(hmotnostS);
        } else if (menuIndex2 == 2) {  
          plnenie(hmotnostV);
        }     
        displayMenu();    
      }
      if (menuIndex2 == 3) { 
        inSubmenu = false;
        menuIndex2 = 0;  
        displayOffset2 = 0;
        delay(100);
        menuIndex = 1;  
        displayOffset2 = 0;
        displayMain();   
      }
    }
    if (digitalRead(buttonPin) == HIGH && test == false) {
      test = true;
    }
    if (digitalRead(buttonPin) == LOW && test == true && i > 20) {
      Oled.firstPage();
      do {
        Oled.setFont(u8g_font_6x12);
        Oled.drawStr(2, 10, "Odstrante nadobu");
        Oled.drawStr(2, 20, "z vahy");
      } while (Oled.nextPage());

      delay(1000);
      displayMenu();
    }  
  }
}

void plnenie(float potrebnahmotnost) {
  bool servoBezi = false;
  bool servoBezi2 = false;
  bool servoBezi3 = false;
  bool hotovo = false;
  bool cakanieNaOdstranenie = false;
  bool cakanieNaNovuNadobu = false;
  bool odstranene = false;
  bool ukoncenie = false;
  while (true) {
    int aktualnahmotnost = scale.get_units();  

    if (!hotovo){
    int percento = (aktualnahmotnost / potrebnahmotnost) * 100;
    if (percento > 100) {
      percento = 100;
    }
      
    Oled.firstPage();
    do {
      Oled.setFont(u8g_font_6x12);
      Oled.drawStr(2, 10, "Plni sa:");
      Oled.drawStr(50, 10, menuItems[menuIndex2]);

      char buffer[20];
      sprintf(buffer, "Naplnene na: %d%%", percento);
      Oled.drawStr(0, 34, buffer);
    } while (Oled.nextPage());

    if (percento < 90 && !servoBezi) {
      myservo.write(180);  
      delay(2000);
      myservo.write(90);  
      servoBezi = true;
    } else if (percento >= 90 && percento < 100 && !servoBezi2) {
      myservo.write(180);   
      delay(1000);         
      myservo.write(90);
      servoBezi2 = true;   
    } else if (percento == 100 && !servoBezi3) {
      myservo.write(180);   
      delay(1000);         
      myservo.write(90); 
      servoBezi3 = true; 
      Oled.firstPage();
      do {
        Oled.setFont(u8g_font_6x12);
        Oled.drawStr(2, 10, "Pockajte");
        Oled.drawStr(2, 20, "3 sekundy");
        Oled.drawStr(2, 30, "med odkvapkava");
      } while (Oled.nextPage()); 
      delay(3000);
      hotovo = true;
      cakanieNaOdstranenie = true;
    }
       
      while(hotovo) {
        aktualnahmotnost = scale.get_units();
        if (cakanieNaOdstranenie) {   
          if (aktualnahmotnost > 10) {
            Oled.firstPage();
            do {
            Oled.setFont(u8g_font_6x12);
            Oled.drawStr(2, 10, "Odstrante naplneny pohar");
            } while (Oled.nextPage());
          }
          else {
            cakanieNaOdstranenie = false; 
            cakanieNaNovuNadobu = true; 
            scale.tare(); 
          }
        }
        else if (cakanieNaNovuNadobu) {
          if (aktualnahmotnost < 10) {
            Oled.firstPage();
            do {
              Oled.setFont(u8g_font_6x12);
              Oled.drawStr(2, 10, "Polozte nadobu");
              Oled.drawStr(2, 20, "na vahu alebo stlacte");
              Oled.drawStr(2, 30, "tlacidlo pre navrat.");
            } while (Oled.nextPage());
            odstranene = true;
          } else if (aktualnahmotnost > 10 && odstranene == true) {
          delay(1000);
          scale.tare(); 
          hotovo = false; 
          cakanieNaNovuNadobu = false;
          odstranene = false;
          servoBezi = false;
          servoBezi2 = false;
         servoBezi3 = false;
          }
        }
        if (digitalRead(buttonPin) == LOW) {
            hotovo = false;
            ukoncenie = true;
        }
      }
    }
    if(ukoncenie)
    {
      break;
    }
    delay(100);
    if (digitalRead(buttonPin) == LOW) {
      myservo.write(180);    
      delay(2000);         
      myservo.write(90);
      displayMenu();
      break;
      
    }
  }
}

void vaha() {
  scale.tare(); 
  while (true) {
    int aktualnahmotnost = scale.get_units();  
    String x = String(aktualnahmotnost);
    Serial.print("Aktualna vaha: ");
    Serial.println(aktualnahmotnost);

    if (aktualnahmotnost <= 0) {
      aktualnahmotnost = 0;
    }

    Oled.firstPage();
    do {
      Oled.setFont(u8g_font_7x14);
      Oled.drawStr(40, 10, "Vaha je:");
      Oled.drawStr(55, 30, x.c_str());
      Oled.drawStr(55, 50, "g");
    } while (Oled.nextPage());
    delay(100);
    if (digitalRead(buttonPin) == LOW) {
      inSubmenu3 = false;
      displayMain();
      break;
    }
  }
}

void kalibracia() {
  int aktualnahmotnost;
  scale.tare(); 
  lastEncoderPos = encoder.read() / 2;
  Oled.firstPage();
  do {
    Oled.setFont(u8g_font_6x12);
    Oled.drawStr(2, 10, "Teraz polozte znamu");
    Oled.drawStr(2, 20, "vahu");
    Oled.drawStr(2, 40, "Pomocou enkoderu");
    Oled.drawStr(2, 50, "nastavte kal. faktor");
    Oled.drawStr(2, 60, "na znamu vahu.");
  } while (Oled.nextPage());

  delay(100);
  while(digitalRead(buttonPin) == HIGH) {}

  while (true) {
    aktualnahmotnost = scale.get_units();  

    Oled.firstPage();
    do {
      Oled.setFont(u8g_font_7x14);
      Oled.drawStr(2, 10, "Vaha je:");
      long newPos = encoder.read() / 2;

      if (abs(newPos - lastEncoderPos) >= 1) {
        if (newPos > lastEncoderPos) {
          CALIBRATION_FACTOR++;
        } else if (newPos < lastEncoderPos) {
          CALIBRATION_FACTOR--;
        }

        lastEncoderPos = newPos;
        scale.set_scale(CALIBRATION_FACTOR);
      }
      Oled.drawStr(60, 10, String(aktualnahmotnost).c_str());
      Oled.drawStr(2, 40, "Kalibracny faktor:");
      Oled.drawStr(2, 55, String(CALIBRATION_FACTOR).c_str());
    } while (Oled.nextPage());

    delay(100);   
    
    if (digitalRead(buttonPin) == LOW) {
      EEPROM.put(EEPROM_ADDR, CALIBRATION_FACTOR);
      inSubmenu2 = false;
      menuIndex2 = 0;
      displayMain(); 
      break;  
    }
  }
}

void displayMain() {
  Oled.firstPage();
  do {
    Oled.setFont(u8g_font_9x18);  
    int lineHeight = 12;          

    for (int i = 0; i < maxVisibleItems; i++) {
      int itemIndex = i + displayOffset;
      if (itemIndex >= mainLength) break;  

      int textWidth = Oled.getStrWidth(mainItems[itemIndex]);  
      int xOffset = (128 - textWidth) / 2;  
      int yPosition = (i + 1) * lineHeight; 

      if (itemIndex == menuIndex) {
        Oled.setColorIndex(1);  
        Oled.drawRFrame(0, yPosition - lineHeight + 2, 128, lineHeight, 2); 
        Oled.setColorIndex(1);  
      } else {
        Oled.setColorIndex(1);  
      }

      Oled.drawStr(xOffset, yPosition, mainItems[itemIndex]);  
    }

    if (mainLength > maxVisibleItems) {
      int scrollBarHeight = 40; 
      int scrollBarTop = map(menuIndex, 0, mainLength - 1, 0, 64 - scrollBarHeight);
      Oled.drawBox(120, scrollBarTop, 6, scrollBarHeight); 
    }

  } while (Oled.nextPage());
}

void displayMenu() {
  Oled.firstPage();
  do {
    Oled.setFont(u8g_font_9x18);  
    int lineHeight = 12;          

    Oled.drawStr(2, 10, "Vyber pohar:"); 

    for (int i = 0; i < maxVisibleItems; i++) {
      int itemIndex = i + displayOffset2;
      if (itemIndex >= menuLength) break;  

      int textWidth = Oled.getStrWidth(menuItems[itemIndex]);  
      int xOffset = (128 - textWidth) / 2;  
      int yPosition = (i + 2) * lineHeight; 

      if (itemIndex == menuIndex2) {
        Oled.setColorIndex(1);  
        Oled.drawRFrame(0, yPosition - lineHeight + 2, 128, lineHeight, 2); 
        Oled.setColorIndex(1); 
      } else {
        Oled.setColorIndex(1); 
      }

      Oled.drawStr(xOffset, yPosition, menuItems[itemIndex]);  
    }

    if (menuLength > maxVisibleItems) {
      int scrollBarHeight = 40;  // Height of the scrollbar
      int scrollBarTop = map(menuIndex2, 0, menuLength - 1, 0, 64 - scrollBarHeight);
      Oled.drawBox(120, scrollBarTop, 6, scrollBarHeight);  // Draw the scrollbar
    }

  } while (Oled.nextPage());
}

void nastavenia() {
  int pv = 0;
  lastEncoderPos = encoder.read() / 2;
  delay(500);
  while (true) {
    Oled.firstPage();
    do {
      Oled.setFont(u8g_font_6x12);
      Oled.drawStr(2, 10, "Nastavenia:");

      long newPos = encoder.read() / 2;

      if (abs(newPos - lastEncoderPos) >= 2) {
        if (newPos > lastEncoderPos) {
          pv = +25;
          zmena2 = true;
        } else if (newPos < lastEncoderPos) {
          pv = -25;
          zmena2 = true;
        }

        lastEncoderPos = newPos;
      }

      String M = String(hmotnostM);
      String S = String(hmotnostS);
      String V = String(hmotnostV);

      if (digitalRead(buttonPin) == LOW && zmena == true) {
          zmena = false;
          settings++;
      }
      else if(digitalRead(buttonPin) == HIGH && zmena == false) {
          zmena = true;
          pv = 0;
      }

      Oled.drawStr(2, 30, menuItems[settings]);
   
      if (settings == 0) {
        Oled.drawStr(2, 50, M.c_str());
        if(zmena2 == true)
        {
          hmotnostM += pv;
          zmena2 = false;
        }
        
      }
    
      else if (settings == 1) {
        Oled.drawStr(2, 50, S.c_str());
        if(zmena2 == true)
        {
          hmotnostS += pv;
          zmena2 = false;
        }
      }
      
      else if (settings == 2) {
        Oled.drawStr(2, 50, V.c_str());
        if(zmena2 == true)
        {
          hmotnostV += pv;
          zmena2 = false;
        }
      }
      
      else if (settings == 3) {
          EEPROM.put(EEPROM_M, hmotnostM);
          EEPROM.put(EEPROM_S, hmotnostS);
          EEPROM.put(EEPROM_V, hmotnostV);
          inSubmenu4 = false;
          settings = 0;
          menuIndex = 3;
          displayOffset = 2;
          displayMain();
          return; 
      }
    } while (Oled.nextPage());
  }
}