module ImageIndexToColor(
  input i_Clk,

  input [4:0] i_ColorIndex,

  input i_DoWrite,
  input [3:0] i_WriteColorIndex,
  input [2:0] i_WriteColor_Red,
  input [2:0] i_WriteColor_Green,
  input [2:0] i_WriteColor_Blue,

  output [2:0] o_Red,
  output [2:0] o_Green,
  output [2:0] o_Blue,

  output reg o_WriteComplete
);
  reg [8:0] r_colors[0:31];

  initial begin
    $readmemb("palette_data.txt", r_colors);
  end

  always @(posedge i_Clk) begin
    if (i_DoWrite) begin
      r_colors[i_WriteColorIndex] <= {
        i_WriteColor_Red, i_WriteColor_Green, i_WriteColor_Blue
      };
      o_WriteComplete <= i_DoWrite;
    end
  end

  assign o_Red = r_colors[i_ColorIndex][8:6];
  assign o_Green = r_colors[i_ColorIndex][5:3];
  assign o_Blue = r_colors[i_ColorIndex][2:0];
endmodule

module TestImageIndexToColor();
  reg i_Clk = 0;

  always #2 i_Clk <= !i_Clk;

  reg [3:0] r_colorIndex = 0;
  wire [2:0] w_Red, w_Green, w_Blue;
  wire w_writeComplete;

  reg r_doWrite = 0;
  reg [2:0] r_WriteColor_Red = 3'b111;
  reg [2:0] r_WriteColor_Green = 3'b000;
  reg [2:0] r_WriteColor_Blue = 3'b001;
  reg [3:0] r_writeColorIndex = 0;

  ImageIndexToColor ii2c (
    .i_Clk(i_Clk),

    .i_ColorIndex(r_colorIndex),

    .i_DoWrite(r_doWrite),
    .i_WriteColorIndex(r_writeColorIndex),
    .i_WriteColor_Red(r_WriteColor_Red),
    .i_WriteColor_Green(r_WriteColor_Green),
    .i_WriteColor_Blue(r_WriteColor_Blue),

    .o_Red(w_Red),
    .o_Green(w_Green),
    .o_Blue(w_Blue),
    .o_WriteComplete(w_writeComplete)
  );

  initial begin
    $dumpfile("test.vcd");
    $dumpvars;

    #2;
    #2;

    r_colorIndex = 1;

    #2;
    #2;

    r_doWrite = 1;

    #2;
    #2;

    r_colorIndex = 15;

    #2;
    #2;

    $finish;
  end
endmodule