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

LiquidCrystal_I2C lcd(0x27,16,2);
Encoder enc(2,3);

const int buttonSelect=4;

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

int menuIndex=0;
int menuLevel=0;

int a = 3;

int pos = 0;
int oldPos = 0;

int value = 0;
int val = 0;

int buttonPin = 4;

bool buttonPressed = false;
bool buttonShortPress = false;
bool buttonLongPress = false;

unsigned long pressDuration;
unsigned long pressStart;

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

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

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

void setup() {
  Serial.begin(9600);
  pinMode(buttonPin, INPUT_PULLUP);
  lcd.init();
  lcd.backlight();
  displayMenu();
}

void loop() {
  currentTime = millis();
  encoder();
  if (currentTime - lastPressTime >= debounceDelay) {
    if (value == 1) {
      moveUp();
      lastPressTime = currentTime;
      upCounter++;
      allCounter++;
    }
    if (value == -1) {
      moveDown();
      lastPressTime = currentTime;
      downCounter++;
      allCounter++;
    }
    if(buttonShortPress == true) {
      selectOption();
      buttonShortPress = false;
      value = 0;
      lastPressTime = currentTime;
      selectCounter++;
      allCounter++;
    }
    if(buttonLongPress == true) {
      menuLevel = 0;
      buttonLongPress = false;
      value = 0;
      displayMenu();
      lastPressTime = currentTime;
    }
  }
}

void encoder() {
  pos = enc.read() / 4;
  if (oldPos != pos) {
    value = pos - oldPos;
    oldPos = pos;
    Serial.println(value);
    if(value == 1){
      val++;
    } else if (value == -1){
      val--;
    }
  }

  bool buttonState = digitalRead(buttonPin);

  if (buttonState == LOW) {
    if (!buttonPressed) {
      buttonPressed = true;
      pressStart = millis();
    }
  } else if (buttonPressed) {
    pressDuration = millis() - pressStart;
    if (pressDuration < 500) {
      buttonShortPress = true;
      Serial.println("Короткое нажатие");
    } else {
      buttonLongPress = true;
      Serial.println("Долгое нажатие");
    }
    buttonPressed = false;
  }
}

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;
  }
  buttonShortPress = false;
  value = 0;
  displayMenu();
}

void moveDown() {
  delay(100);
  menuIndex++;
  if(menuIndex>a){
    menuIndex=0;
  }
  buttonShortPress = false;
  value = 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 = 2;
        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("Kislovodsk");
      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();
    }
  }
}