#include <LiquidCrystal_I2C.h>
#include <Wire.h>


LiquidCrystal_I2C lcd(0x27,16,2);

const int buttonSelect=8;

int upCounter = 0;
int downCounter = 0;
int selectCounter = 0;
int allCounter = 0;

int menuIndex=0;
int menuLevel=0;

const int potPin = A3;
int potVal = 0;
int prevVal = 0;
int val = 0;
int a = 2;

int ooo;

String mainMenu[]={
  "Settings",
  "Info",
  "Power off",
};

const int mainMenuLength = sizeof(mainMenu) / sizeof(mainMenu[0]);

String settingsMenu[] = {
  "Light",
  "Contrast",
  "back"
};

const int settingsMenuLength = sizeof(settingsMenu) / sizeof(settingsMenu[0]);

String infoMenu[] = {
  "FIO",
  "Group",
  "City",
  "Buttons",
  "back",
};

const int infoMenuLength = sizeof(infoMenu) / sizeof(infoMenu[0]); 

unsigned long lastPressTime = 0;
unsigned long currentTime = 0;
const unsigned long debounceDelay = 200;

void setup() {
  Serial.begin(115200);
  lcd.init();
  lcd.backlight();

 pinMode(buttonSelect, INPUT_PULLUP);
 
displayMenu();
}

void loop() {
  currentTime = millis();
  potVal = analogRead(potPin);
  val = map(potVal, 0, 750, 0, a);
    if (currentTime - lastPressTime >= debounceDelay) {
      if (val < prevVal) {
        moveUp();
        lastPressTime = currentTime;
        prevVal = val;
        upCounter++;
        allCounter++;
        Serial.println("Value: " + String(val));
        Serial.println("PotValue: " + String(potVal));
      }
      if (val > prevVal) {
        moveDown();
        lastPressTime = currentTime;
        prevVal = val;
        downCounter++;
        allCounter++;
        Serial.println("Value: " + String(val));
        Serial.println("PotValue: " + String(potVal));
      }
      if(digitalRead(buttonSelect) == LOW) {
        selectOption();
        lastPressTime = currentTime;
        selectCounter++;
        allCounter++;
        Serial.println("Value: " + String(val));
        Serial.println("PotValue: " + String(potVal));
      }
    }
  }

  void displayMenu(){
    lcd.clear();

    if (menuLevel == 0) {
      lcd.setCursor(0,0);
      lcd.print(">"+ mainMenu[menuIndex]);

      if (menuIndex + 1 < mainMenuLength) {
        lcd.setCursor(0,1);
        lcd.print(" " + mainMenu[menuIndex + 1]);
      }
    }

    else if (menuLevel == 1) {
      lcd.setCursor(0,0);
      lcd.print(">"+ settingsMenu[menuIndex]);

      if (menuIndex + 1 < settingsMenuLength) {
        lcd.setCursor(0,1);
        lcd.print(" " + settingsMenu[menuIndex + 1]);
      }
    }

    else if (menuLevel == 2) {
      lcd.setCursor(0,0);
      lcd.print(">"+ infoMenu[menuIndex]);

      if (menuIndex + 1 < infoMenuLength) {
        lcd.setCursor(0,1);
        lcd.print(" " + infoMenu[menuIndex + 1]);
      }
    }

  }

  void moveUp() {
    delay(100);
    menuIndex--;
    if(menuIndex<0){
      menuIndex=a;
    }
    displayMenu();
  }

  void moveDown() {
    delay(100);
    menuIndex++;
    if(menuIndex>a){
      menuIndex=0;
    }
    displayMenu();
  }

  void selectOption() {
    if (menuLevel == 0) {
      if (menuIndex == 0) {
        menuLevel = 1;
        menuIndex = 0;
        a = 2;
        displayMenu();
      }
      else if (menuIndex == 1) {
        menuLevel = 2;
        menuIndex = 1;
        a = 3;
        displayMenu();
      }
      else if (menuIndex == 2) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("GGG");
        delay(2000);
        lcd.noBacklight();
      }
    }
    else if (menuLevel == 1) {
      if (menuIndex == 0) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Light");
        delay(2000);
        displayMenu();
      }
      else if (menuIndex == 1) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Contr");
        delay(2000);
        displayMenu();
      }
      else if (menuIndex == 2) {
        menuLevel = 0;
        menuIndex = 0;/////////////
        a = 2;
        displayMenu();
      }
    }
    else if (menuLevel == 2) {
      if (menuIndex == 0) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Terehov.I.N");
        delay(1000);
        displayMenu();
      }
      else if (menuIndex == 1) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("63-D9-3KCK");
        delay(1000);
        displayMenu();
      }
      else if (menuIndex == 2) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("YFA");
        delay(1000);
        displayMenu();
      }
      else if (menuIndex == 3) {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("up= " + String(upCounter) + ";down= " + String(downCounter) + ";");
        lcd.setCursor(0, 1);
        lcd.print("sel= " + String(selectCounter) + ";all= " + String(allCounter) + ";");
        delay(2000);
        displayMenu();
      }
      else if (menuIndex == 4) {
        a=2;
        menuLevel = 0;
        menuIndex = 1;
        

        Serial.println(" " +String (menuLevel));
      
        displayMenu();
    }
  }
  }