Valid move for Pawn logic

valid_move_pawn.rb

class Pawn < Piece
    def valid_move?(x,y)
    #First move. Allowed to move 1 or 2 spaces.
    if self.x_position #how to say this is the first move??
    return false if (self.x_position - x).abs > 2 || (self.y_position - y).abs > 2
    
    #All moves. Allowed to move 1 space.
    return false if (self.x_position - x).abs > 1 || (self.y_position - y).abs > 1

    #Up 1 and horizonal to capture.

    #Cannot capture vertically.
    end
  end
end
end