Distance method for Chess Application

distance.rb

 def distance(destination_row, destination_col)
    if self.vertical?(destination_row, destination_col)
      return (destination_row - current_row_index).abs
    elsif self.horizontal?(destination_row, destination_col)
      return (destination_col - current_column_index).abs
    elsif self.diagonal?(destination_row, destination_col)
      return (destination_col - current_column_index).abs
      # destination_col - current_row_index
    else 
      puts "Invalid Input"
    end
  end