static byte unique_button_id = 0;

class Button
{
private:
  byte _pin = 0;
  byte _state = 0;
  float _time_click = 500.0f;
  float _time_long_click = 2000.0f;
  float _time_down = 0.0f;
  unsigned long _old_time = 0.0f;

public:
  byte ID = 0;

  void (*ptrF)(Button* arg1);

  Button()
  {
    ID = unique_button_id;
    unique_button_id += 1;
  };

  Button(byte pin)
  {
    _pin = pin;
    pinMode(_pin, INPUT);
    digitalWrite(_pin, LOW);
  }

  void SetData(byte pin, void* event_function)
  {
    _pin = pin;
    pinMode(_pin, INPUT);
    digitalWrite(_pin, LOW);
    ptrF = event_function;
  }

  void Loop()
  {
    Serial.println(digitalRead(_pin));
    if (digitalRead(_pin) == LOW)
    {
      _state = 0;
      _time_down = 0.0f;
      _old_time = millis();
      return;
    }

    _time_down += millis() - _old_time;
    _old_time = millis();
    //Serial.println(_time_down);
    if (_time_down > _time_click)
    {
      if (_state == 0)
      {
        _state = 1;
        ptrF(this);
      }
    }
  }
};

Button Buttons[4];

void setup() 
{
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(12, OUTPUT);
  digitalWrite(12, HIGH);
  Buttons[0].SetData(2, Button1Click);
  Buttons[1].SetData(3, Button2Click);
  Buttons[2].SetData(4, Button3Click);
  Buttons[3].SetData(5, Button4Click);
}

void loop() 
{
  // put your main code here, to run repeatedly:
  for(int id = 0; id < 4; id++)
    Buttons[id].Loop();

}

void OnButtonClick(byte id)
{
  Serial.print("ID Button click = ");
  Serial.println(id);
}

void Button1Click(Button* self)
{
  Serial.print("ID Button click = ");
  Serial.println(self->ID);
}

void Button2Click(Button* self)
{
  Serial.print("ID Button click = ");
  Serial.println(self->ID);
}

void Button3Click(Button* self)
{
  Serial.print("ID Button click = ");
  Serial.println(self->ID);
}

void Button4Click(Button* self)
{
  Serial.print("ID Button click = ");
  Serial.println(self->ID);
}