module pinballmachine (input clk, reset_bar,
                        output reg [0:2] pstate, output reg [0:2] nstate,
                        output reg [0:4] games, output reg [0:15] points,
                        output reg [0:4] pgames, output reg [0:15] ppoints,
                        input h100, h200, bop_hit, ball_lost,
                        output reg bop_en, green, yellow, red, gold);

parameter init = 0, start = 1, h200one = 2, h200two = 3, h200three = 4;

// State flipflops
always @(posedge clk, negedge reset_bar)
  begin
    if (reset_bar == 0)
      pstate <= init;
    else
      pstate <= nstate;
  end

// Next state and output decoder
always @(*)
  begin
    case (pstate)
      init: begin
              nstate <= start;
              points <= 0;
              games <= 0;
              green <= 0; 
              yellow <= 0; 
              red <= 0; 
              gold <= 0; 
              bop_en <= 0;
            end
      start:begin
              bop_en <= 0;
              if (! ball_lost)
                begin
                  if (h100 == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 100;
                      games <= 0;
                      green <= 1;
                      yellow <= 0;
                      red <= 0;
                      gold <= 0;
                    end
                  else if (h200 == 1)
                    begin
                      nstate <= h200one;
                      points <= ppoints + 200;
                      games <= 0;
                      green <= 0;
                      yellow <= 1;
                      red <= 0;
                      gold <= 0;
                    end
                  else
                    begin
                      nstate <= start;
                      points <= 0;
                      games <= 0;
                    end
                end
              else
                begin
                  nstate <= start;
                  points <= 0;
                  games <= 0;
                  green <= 0; 
                  yellow <= 0; 
                  red <= 0; 
                  gold <= 0; 
                end
            end
      h200one:
            begin
              bop_en <= 0;
              if (! ball_lost)
                begin
                  if (h100 == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 100;
                      games <= 0;
                      green <= 1;
                      yellow <= 0;
                      red <= 0;
                      gold <= 0;
                    end
                  else if (h200 == 1)
                    begin
                      nstate <= h200two;
                      points <= ppoints + 200;
                      games <= 0;
                      green <= 0;
                      yellow <= 1;
                      red <= 0;
                      gold <= 0;
                    end
                  else
                    begin
                      nstate <= h200one;
                      points <= 0;
                      games <= 0;
                    end
                end
              else
                begin
                  nstate <= start;
                  points <= 0;
                  games <= 0;
                  green <= 0; 
                  yellow <= 0; 
                  red <= 0; 
                  gold <= 0; 
                end
            end
      h200two:
            begin
              if (! ball_lost)
                begin
                  if (h100 == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 100;
                      games <= 0;
                      green <= 1;
                      yellow <= 0;
                      red <= 0;
                      gold <= 0;
                      bop_en <= 0;
                    end
                  else if (h200 == 1)
                    begin
                      nstate <= h200three;
                      points <= ppoints + 200;
                      games <= 0;
                      green <= 0;
                      yellow <= 0;
                      red <= 1;
                      gold <= 0;
                      bop_en <= 1;
                    end
                  else
                    begin
                      nstate <= h200two;
                      points <= 0;
                      games <= 0;
                    end
                end
              else
                begin
                  nstate <= start;
                  points <= 0;
                  games <= 0;
                  green <= 0;
                  yellow <= 0;
                  red <= 0;
                  gold <= 0;
                  bop_en <= 0;
                end
            end
      h200three:
            begin
              if (! ball_lost)
                begin
                  if (h100 == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 100;
                      games <= 0;
                      green <= 1;
                      yellow <= 0;
                      red <= 0;
                      gold <= 0;
                      bop_en <= 0;
                    end
                  else if (h200 == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 200;
                      games <= 0;
                      green <= 0;
                      yellow <= 1;
                      red <= 0;
                      gold <= 0;
                      bop_en <= 0;
                    end
                  else if (bop_hit == 1)
                    begin
                      nstate <= start;
                      points <= ppoints + 600;
                      games <= pgames + 1;
                      green <= 0;
                      yellow <= 0;
                      red <= 0;
                      gold <= 1;
                      bop_en <= 0;
                    end
                  else
                    begin
                      nstate <= h200three;
                      points <= 0;
                      games <= 0;
                    end
                end
              else
                begin
                  nstate <= start;
                  points <= 0;
                  games <= 0;
                  green <= 0; 
                  yellow <= 0; 
                  red <= 0; 
                  gold <= 0; 
                  bop_en <= 0;
                end
            end
    endcase
  end

// Point counter
always @(posedge clk, negedge reset_bar)
  begin
    if (reset_bar == 0)
      ppoints <= 0;
    else if (points)
      ppoints <= points;
  end

// Game counter
always @(posedge clk, negedge reset_bar)
  begin
    if (reset_bar == 0)
      pgames <= 0;
    else if (games)
      pgames <= games;
  end

endmodule

module testbench (output reg clk, 
                  output reg reset_bar,
                  input [0:2] pstate, input [0:2] nstate,
                  input [0:4] games, input [0:15] points,
                  input [0:4] pgames, input [0:15] ppoints,
                  output reg h100, h200, bop_hit, ball_lost,
                  input bop_en, green, yellow, red, gold);

// Test Bench
initial
  begin
    $dumpvars;
    $dumpfile ("pinballmachine2.vcd");
    clk <= 0;
    reset_bar <= 1;
    h100 <= 0;
    h200 <= 0;
    bop_hit <= 0;
    ball_lost <= 0;
    #10     reset_bar <= 0;
    #10     reset_bar <= 1;
            clk <= 1;
    #10     clk <= 0;
    #10     clk <= 1;
            h100 <= 1;
            h200 <= 0;
    #10     clk <= 0;
    #10     clk <= 1;
    #10     clk <= 0;
    #10     clk <= 1;
    #10     clk <= 0;
    #10     clk <= 1;
            h100 <= 0;
    #10     clk <= 0;
    #10     clk <= 1;
    #10     clk <= 0;
    #10     h200 <= 1;
            clk <= 1;
    #10     clk <= 0;
    #10     clk <= 1;
    #10     clk <= 0;
    #10     h200 <= 0;
            clk <= 1;
    #10     clk <= 0;
    #10     h200 <= 1;
            clk <= 1;
    #10     clk <= 0;
    #10     bop_hit <= 1;
            h200 <= 0;
            clk <= 1;
    #10     clk <= 0;
    #10     bop_hit <= 0;
            clk <= 1;
    #10     clk <= 0;
    #10     clk <= 1;
    #10     clk <= 0; 
    #10     clk <= 1;
    #10     clk <= 0; 
    #350    $finish; 
  end

endmodule

module system ();
  wire clk; 
  wire reset_bar;
  wire [0:2] pstate;
  wire [0:2] nstate;
  wire [0:4] games;
  wire [0:15] points;
  wire [0:4] pgames;
  wire [0:15] ppoints;
  wire h100, h200, bop_hit, ball_lost;
  wire bop_en;
  wire green, yellow, red, gold;

 pinballmachine (clk, reset_bar, pstate, nstate, games, points,
                 pgames, ppoints, h100, h200, bop_hit, ball_lost,
                 bop_en, green, yellow, red, gold);
 testbench    (clk, reset_bar, pstate, nstate, games, points,
               pgames, ppoints, h100, h200, bop_hit, ball_lost,
               bop_en, green, yellow, red, gold);

endmodule