[opismahname]

   1.
      local function eventHandler(self, event, ...)
   2.
          local active = UnitBuff('player', 'Righteous Fury')
   3.
          if not hasrf and active then
   4.
              hasrf = true
   5.
              print('Rigtheous Fury has been activated')
   6.
          elseif hasrf and not active then
   7.
              hasrf = false
   8.
          end
   9.
      end

Don't think it's right yet, this is hard xD