//16x2 LCD
#include <LiquidCrystal_I2C.h> //SDA = A4, SCL = A5
LiquidCrystal_I2C lcd(0x27, 16, 2);


//Defining pins for rotary encoder
const int RotaryCLK = 2; //CLK pin on the rotary encoder
const int RotaryDT = 4; //DT pin on the rotary encoder
const int RotarySW = 3; //SW pin on the rotary encoder (Button function)

//Defining variables for rotary encoder and button
int ButtonCounter = 0; //counts the button clicks
int RotateCounter = 0; //counts the rotation clicks
int Rotatesubcounter = 0;
bool rotated = true; //info of the rotation
bool ButtonPressed = false; //info of the button

//Statuses
int CLKNow;
int CLKPrevious;
int DTNow;
int DTPrevious;

//-----------------------User definitions------------------

bool Menu = true ;
bool SubMenu = false ; 
bool RotateFlag = false; 
bool flag = true; 
// Timers
float TimeNow1;
float TimeNow2;


//------------------------------

//Define the LCD Arrow (-->)
uint8_t arrow[8] = {0x00, 0x04 ,0x06, 0x1f, 0x06, 0x04, 0x00}; 
  
  enum pages{root_menu,submenu,return_back};
  enum selected_menu{no_menu_selected,menu1,menu2,menu3,menu4};
  enum selected_submenu{no_submenu_selected,submenu1,submenu2,back};

  enum selected_menu menu_x = no_menu_selected;
  enum selected_submenu submenu_x = no_submenu_selected;
  enum pages current_page = root_menu;

void setup()
{
 	 //Serial.begin(9600); //we don't use the serial in this example

	//------------------------------------------------------
	lcd.init();                     // initialize the lcd 	
	lcd.backlight();
	//------------------------------------------------------
  lcd.setCursor(0,0); 
  lcd.print("ElectroWave");
  delay(500);
  lcd.clear();
  delay(1000); //wait 3 sec
  //------------------------------------------------------
   //setting up pins	
   pinMode(2, INPUT_PULLUP);
   pinMode(3, INPUT_PULLUP);
   pinMode(4, INPUT_PULLUP);


	//Create the Arrrow for LCD (-->)
  lcd.createChar(0, arrow);

  
  //Store states
  CLKPrevious = digitalRead(RotaryCLK);
  DTPrevious = digitalRead(RotaryDT);
    
  attachInterrupt(digitalPinToInterrupt(RotaryCLK), rotate, CHANGE);
  attachInterrupt(digitalPinToInterrupt(RotarySW), buttonPressed, FALLING); //either falling or rising but never "change".

  TimeNow1 = millis(); //Start timer 1  
}


void loop()
{

switch(current_page)
{
  case root_menu: root_menu_func(); break;
  case submenu1:    SUBMENU_1(); break;
  case return_back: current_page=root_menu; break;
}



}

void root_menu_func()
{
if(rotated == true) //refresh the CLK
  {
      switch(RotateCounter)
    {
    //------------------------------------------Menu_1---------------------------------------------------
      case 0:  //Menu 0 case
      screen_0();
      menu_x=menu1;
      break; //Break Menu 0 --> case 0

    //------------------------------------------Menu_2---------------------------------------------------
      case 1:
      screen_1();
      
      break;

    //------------------------------------------Menu_3---------------------------------------------------  
      case 2:
      screen_2();

      break;
    //------------------------------------------Menu_4---------------------------------------------------  
      case 3:
      screen_3();

      break;
     
    }    
  }  
    //ButtonPressed = false; //reset this variable
}


void submenu1_func()
{
      
      
    lcd.clear();
      lcd.setCursor(0,0);   
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("xxxxxxxxxxxxxxxxxxxxxx");
}


void which_menu_is_selected(selected_menu menu_x,selected_submenu submenu_x)
{

if (menu_x == menu1 && submenu_x == no_submenu_selected)
{
   SUBMENU_1();
}
else if (menu_x == menu1 && submenu_x == back)
{
  root_menu_func();
}
else
{
      lcd.clear();
      lcd.setCursor(0,0);   
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("xxxx34566xxxxxxxx");
}

}


void buttonPressed()
{  

  if(menu_x == menu1)
  {
  current_page=submenu;

  }
  if(submenu_x == back)
  {
    current_page=return_back;
    submenu_x =no_submenu_selected;
  }
  //This timer is a "software debounce". It is not the most effective solution, but it works
  TimeNow2 = millis();
  if(TimeNow2 - TimeNow1 > 500)
  {    
    //ButtonPressed = true;    
    SubMenu = true; 
  }
  TimeNow1 = millis();  //"reset" timer; the next 500 ms is counted from this moment

   //which_menu_is_selected(menu_x,submenu_x);

}

void rotate()
{
  CLKNow = digitalRead(RotaryCLK); //Read the state of the CLK pin

  // If last and current state of CLK are different, then a pulse occurred  
    if (CLKNow != CLKPrevious  && CLKNow == 1)
    {
    // If the DT state is different than the CLK state then
    // the encoder is rotating CCW so increase
      if ((digitalRead(RotaryDT) != CLKNow) && (Menu==true) )  
      {      
          RotateCounter++;
      }
      else
      {        
        RotateCounter--;
      }
     
     
      if ((digitalRead(RotaryDT) != CLKNow) && (Menu==false) )
        {
          Rotatesubcounter++;
        }
      else
        {        
          Rotatesubcounter--;
        }
    
    }

      if(RotateCounter > 3 )
      {
       RotateCounter = 0;
      }

      if(RotateCounter < 0)
      {
        RotateCounter = 3;  
      } 	

      if(Rotatesubcounter > 2 )
      {
       Rotatesubcounter = 0;
      }

      if(Rotatesubcounter < 0)
      {
        Rotatesubcounter = 2;  
      } 
      

  CLKPrevious = CLKNow;  // Store last CLK state
  rotated = true;
}



void MENU_ID()
{
    if(rotated == true) //refresh the CLK
  {
      switch(RotateCounter)
    {
    //------------------------------------------Menu_1---------------------------------------------------
      case 0:  //Menu 0 case
      screen_0();
      menu_x=menu1;
      break; //Break Menu 0 --> case 0

    //------------------------------------------Menu_2---------------------------------------------------
      case 1:
      screen_1();
      menu_x=menu2;
      break;

    //------------------------------------------Menu_3---------------------------------------------------  
      case 2:
      screen_2();

      break;
    //------------------------------------------Menu_4---------------------------------------------------  
      case 3:
      screen_3();

      break;
     
    }    
  }  
    //ButtonPressed = false; //reset this variable
}
  


void screen_0()
{
      //lcd.clear();  
      lcd.setCursor(7,0); 
      lcd.print("     ");   

      lcd.setCursor(0,0);   //Stat at the first row first column
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("Menu 1");

      lcd.setCursor(6,1); 
      lcd.print("     ");

      lcd.setCursor(0,1); 
      lcd.print("Menu 2");

      menu_x = menu1;
}

void screen_1()
{
      //lcd.clear();  
      lcd.setCursor(6,0); 
      lcd.print("     "); 

      lcd.setCursor(0,0); 
      lcd.print("Menu 1");

      lcd.setCursor(7,0); 
      lcd.print("     ");

      lcd.setCursor(0,1);   //Stat at the first row first column
      lcd.write(0);  
      lcd.setCursor(1,1); 
      lcd.print("Menu 2");
      menu_x = menu2;

}

void screen_2()
{
      //lcd.clear(); 
      lcd.setCursor(7,0); 
      lcd.print("     ");

      lcd.setCursor(0,0);   //Stat at the first row first column
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("Menu 3");

      lcd.setCursor(6,1); 
      lcd.print("     ");

      lcd.setCursor(0,1); 
      lcd.print("Menu 4");
      menu_x = menu3;
}

void screen_3()
{
      //lcd.clear();  
      lcd.setCursor(6,0); 
      lcd.print("     "); 

      lcd.setCursor(0,0); 
      lcd.print("Menu 3");
      lcd.setCursor(0,1);   //Stat at the first row first column
      lcd.write(0);  

      lcd.setCursor(7,0); 
      lcd.print("     ");

      lcd.setCursor(1,1); 
      lcd.print("Menu 4");
      menu_x = menu4;
}

//---------------------------SubMenu Void------------------------------
void subscreen_0()
{
      
      //lcd.clear();     
      lcd.setCursor(0,0);   //Stat at the first row first column
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("SubMenu 1");
      lcd.setCursor(0,1); 
      lcd.print("SubMenu 2");
      submenu_x = submenu1;
}

void subscreen_1()
{
      //lcd.clear();  
      lcd.setCursor(0,0); 
      lcd.print("SubMenu 1");
      lcd.setCursor(0,1);   //Stat at the first row first column
      lcd.write(0);  
      lcd.setCursor(1,1); 
      lcd.print("SubMenu 2");
      submenu_x = submenu2;
}

void subscreen_2()
{
      lcd.clear();     
      lcd.setCursor(0,0);   //Stat at the first row first column
      lcd.write(0);   
      lcd.setCursor(1,0); 
      lcd.print("Back");
      submenu_x = back;
}

void SUBMENU_1()
{



if (rotated==true)
  {
     switch(Rotatesubcounter)
    {
    //------------------------------------------Menu_1---------------------------------------------------
      case 0:  //Menu 0 case
      subscreen_0();
      break; //Break Menu 0 --> case 0

    //------------------------------------------Menu_2---------------------------------------------------
      case 1:
      subscreen_1();

      break;

    //------------------------------------------Menu_3---------------------------------------------------  
      case 2:
      subscreen_2();

      break;
    //------------------------------------------Menu_4---------------------------------------------------  
     
    } 

}
         
    

}


void SUBMENU_2()
{
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("Submenu2"); 
    delay(1000); 
    Menu = true ;
    SubMenu = false ; 
}