// nandgame arithmetic unit

`timescale 1us/1us

`include "nandgame_types.v"

`ifndef NANDGAME_ARU
`define NANDGAME_ARU

module  arith_unit #(
  parameter DATA_WIDTH = 16
) (
  input [(DATA_WIDTH-1):0] X,
  input [(DATA_WIDTH-1):0] Y,
  input ArithCode operation,

  output logic [(DATA_WIDTH-1):0] RES
);

always_comb begin
    case (operation)
        ARITH_PLUS: RES = X + Y;
        ARITH_MINUS:  RES = X - Y;
        ARITH_INC: RES = X + 1;
        ARITH_DEC: RES = X - 1;
        default: RES = 0;
    endcase
end

endmodule

`endif