package Tiler_Test;

import Connectable::*;
import GetPut::*;
import ClientServer::*;
import Assert::*;
import StmtFSM::*;
import LFSR::*;
import Probe::*;

import Testing::*;
import Tiler::*;
import VRAM::*;

interface Test;
   method Action start();
   method Bool done();
endinterface

(* synthesize *)
module mkTestPixelcoordToTileSubcoord(Test);
   let testflags <- mkTestFlags();
   Reg#(Bool) run <- mkReg(False);
   Reg#(Bool) finished <- mkReg(False);

   function Action check_pxc_to_tsc(PixelCoord screen_pixel, TilePixelCount pixels_per_tile, TileCount num_tiles, ExtendedPixelCoord scroll_offset, TileCoord want_tile, TilePixelCoord want_subtile);
      return action
                let got = pixelcoord_to_tilesubcoord(screen_pixel, pixels_per_tile, num_tiles, scroll_offset);
                let want = TileSubcoord{tile: want_tile, pixel: want_subtile};
                if (testflags.verbose)
                   $display("pixelcoord_to_tilesubcoord(", screen_pixel, ", ", pixels_per_tile, ", ", num_tiles, ", ", scroll_offset, ") = ", fshow(got), ", want ", fshow(want));
                dynamicAssert(got == want, "wrong output from pixelcoord_to_tilesubcoord");
             endaction;
   endfunction

   rule test (run && !finished);
      // Basic conversion with 32x8px tiles
      check_pxc_to_tsc(0, 8, 32, 0,
                       0, 0);
      check_pxc_to_tsc(5, 8, 32, 0,
                       0, 5);
      check_pxc_to_tsc(7, 8, 32, 0,
                       0, 7);
      check_pxc_to_tsc(8, 8, 32, 0,
                       1, 0);
      check_pxc_to_tsc(9, 8, 32, 0,
                       1, 1);

      // 32x16px tiles
      check_pxc_to_tsc(9, 16, 32, 0,
                       0, 9);
      check_pxc_to_tsc(15, 16, 32, 0,
                       0, 15);
      check_pxc_to_tsc(16, 16, 32, 0,
                       1, 0);

      // Tile wraparound at 32x8
      check_pxc_to_tsc(255, 8, 32, 0,
                       31, 7);
      check_pxc_to_tsc(256, 8, 32, 0,
                       0, 0);
      check_pxc_to_tsc(511, 8, 32, 0,
                       31, 7);
      check_pxc_to_tsc(512, 8, 32, 0,
                       0, 0);

      // Tile wraparound at 64x8
      check_pxc_to_tsc(256, 8, 64, 0,
                       32, 0);
      check_pxc_to_tsc(511, 8, 64, 0,
                       63, 7);
      check_pxc_to_tsc(512, 8, 64, 0,
                       0, 0);

      // Scroll offset
      check_pxc_to_tsc(0, 8, 32, 42,
                       5, 2);
      check_pxc_to_tsc(1, 8, 32, 42,
                       5, 3);
      check_pxc_to_tsc(5, 8, 32, 42,
                       5, 7);
      check_pxc_to_tsc(6, 8, 32, 42,
                       6, 0);
      check_pxc_to_tsc(6, 8, 32, 41,
                       5, 7);

      // Scroll offset vs. wraparound
      check_pxc_to_tsc(255, 8, 32, 2,
                       0, 1);
      check_pxc_to_tsc(0, 8, 32, 3072,
                       0, 0);
      check_pxc_to_tsc(0, 8, 32, 3071,
                       31, 7);

      finished <= True;
   endrule

   method Action start() if (!run);
      run <= True;
   endmethod
   method done = finished._read;
endmodule

(* synthesize *)
module mkTestPaletteExpander(Test);
   let testflags <- mkTestFlags();
   let cycles <- mkCycleCounter();

   let dut <- mkPaletteExpander();
   let got_probe <- mkProbe();
   let got_done_probe <- mkProbe();
   (* no_implicit_conditions,fire_when_enabled *)
   rule probe_done;
      got_done_probe <= dut.done;
   endrule

   function Action check_pixel(PaletteIndex want);
      return action
                let got <- dut.pixel();
                got_probe <= got;
                if (testflags.verbose)
                   $display("PaletteExpander.pixel() = %0d, want %0d", got, want);
                dynamicAssert(got == want, "wrong PaletteExpander output");

                let got_done = dut.done();
                let want_done = False;
                if (testflags.verbose)
                   $display("PaletteExpander.done() = ", fshow(got_done), ", want ", fshow(want_done));
                dynamicAssert(got_done == want_done, "wrong PaletteExpander done()");

                dynamicAssert(cycles == 1, "output took more than 1 cycle");
                cycles.reset();
             endaction;
   endfunction

   let fsm <- mkFSM(par
      seq
         dut.expand('h8e, 8, Bpp1);
         dut.expand('ha4, 4, Bpp2);
         dut.expand('h6c, 2, Bpp4);
         dut.expand('h4d, 1, Bpp8);

         dut.expand('h8e, 5, Bpp1);
         dut.expand('ha4, 3, Bpp2);
         dut.expand('h6c, 1, Bpp4);
      endseq

      seq
         cycles.reset();

         // 0x8e, 1bpp
         check_pixel(1);
         check_pixel(0);
         check_pixel(0);
         check_pixel(0);
         check_pixel(1);
         check_pixel(1);
         check_pixel(1);
         check_pixel(0);

         // 0xa4, 2bpp
         check_pixel(2);
         check_pixel(2);
         check_pixel(1);
         check_pixel(0);

         // 0x6c, 4bpp
         check_pixel(6);
         check_pixel(12);

         // 0x4d, 8bpp
         check_pixel('h4d);

         // 0x8d, 1bpp, first 5 only
         check_pixel(1);
         check_pixel(0);
         check_pixel(0);
         check_pixel(0);
         check_pixel(1);

         // 0xa4, 2bpp, first 3 only
         check_pixel(2);
         check_pixel(2);
         check_pixel(1);

         // 0x6c, 4bpp, first only
         check_pixel(6);

         action
            dynamicAssert(dut.done, "PaletteExpander not done after processing all requests");
            dynamicAssert(cycles == 1, "done flag took too long to assert");
         endaction
      endseq

   endpar);

   method start = fsm.start;
   method done = fsm.done;
endmodule

(* synthesize *)
module mkTestTileRenderer(Test);
   let testflags <- mkTestFlags();
   let cycles <- mkCycleCounter();

   let vram <- mkVRAM(4);
   let dut <- mkTileRenderer();
   mkConnection(dut.vram, vram.tile1);

   let got_probe <- mkProbe();
   let want_probe <- mkProbe();
   let done_probe <- mkProbe();
   (* no_implicit_conditions,fire_when_enabled *)
   rule set_done_probe;
      done_probe <= dut.done();
   endrule

   function Action check_pixel(PaletteIndex want);
      return action
                let got <- dut.tiles.response.get();
                got_probe <= got;
                want_probe <= want;
                if (testflags.verbose)
                   $display("TileRenderer.get() = %02x, want %02x", got, want);
                dynamicAssert(got == want, "wrong pixel rendered");
             endaction;
   endfunction

   Reg#(VRAMAddr) i <- mkReg(0);
   LFSR#(Bit#(8)) rnd <- mkLFSR_8();
   let populate_vram = seq
      for (i <= 0; i < 32; i <= i+1) action
         let val = rnd.value();
         if (testflags.verbose)
            $display("VRAM.write(%0d, 0x%02x) (%0d, %08b)", i, val, val, val);
         vram.cpu.request.put(VRAMRequest{
            addr: i,
            data: tagged Valid rnd.value
         });
         rnd.next();
      endaction
   endseq;

   let test_basic_render = seq
      dut.tiles.request.put(TileRequest{
         tile_row_addr: 1,
         start_col: 0,
         end_col: 7,
         bpp: Bpp1,
         flip: False
      });
      check_pixel(1);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(1);
      check_pixel(1);
      check_pixel(1);
      check_pixel(0);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 0,
         start_col: 0,
         end_col: 7,
         bpp: Bpp1,
         flip: False
      });
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 0,
         end_col: 7,
         bpp: Bpp2,
         flip: False
      });
      check_pixel(1);
      check_pixel(0);
      check_pixel(1);
      check_pixel(3);
      check_pixel(2);
      check_pixel(2);
      check_pixel(3);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 0,
         end_col: 7,
         bpp: Bpp4,
         flip: False
      });
      check_pixel(4);
      check_pixel(7);
      check_pixel(10);
      check_pixel(13);
      check_pixel(13);
      check_pixel(8);
      check_pixel(6);
      check_pixel(12);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 4,
         start_col: 0,
         end_col: 7,
         bpp: Bpp8,
         flip: False
      });
      check_pixel('hd8);
      check_pixel('h6c);
      check_pixel('h36);
      check_pixel('h1b);
      check_pixel('h83);
      check_pixel('hcf);
      check_pixel('he9);
      check_pixel('hfa);
   endseq;

   let test_stalled_consumer = par
      seq
         dut.tiles.request.put(TileRequest{
            tile_row_addr: 12,
            start_col: 0,
            end_col: 7,
            bpp: Bpp8,
            flip: False
            });
         dut.tiles.request.put(TileRequest{
            tile_row_addr: 4,
            start_col: 0,
            end_col: 7,
            bpp: Bpp8,
            flip: False
         });
      endseq

      seq
         check_pixel('h7d);
         check_pixel('hb0);
         check_pixel('h58);
         check_pixel('h2c);
         repeat (10) noAction;
         check_pixel('h16);
         check_pixel('h0b);
         check_pixel('h8b);
         check_pixel('hcb);

         repeat (5) noAction;
         check_pixel('hd8);
         check_pixel('h6c);
         check_pixel('h36);
         repeat (5) noAction;
         check_pixel('h1b);
         check_pixel('h83);
         check_pixel('hcf);
         check_pixel('he9);
         check_pixel('hfa);
      endseq
   endpar;

   let test_scrolled_start = seq
      dut.tiles.request.put(TileRequest{
         tile_row_addr: 1,
         start_col: 3,
         end_col: 7,
         bpp: Bpp1,
         flip: False
      });
      check_pixel(0);
      check_pixel(1);
      check_pixel(1);
      check_pixel(1);
      check_pixel(0);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 1,
         end_col: 7,
         bpp: Bpp4,
         flip: False
      });
      check_pixel(7);
      check_pixel(10);
      check_pixel(13);
      check_pixel(13);
      check_pixel(8);
      check_pixel(6);
      check_pixel(12);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 4,
         start_col: 3,
         end_col: 7,
         bpp: Bpp2,
         flip: False
      });
      check_pixel(0);
      check_pixel(1);
      check_pixel(2);
      check_pixel(3);
      check_pixel(0);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 12,
         start_col: 3,
         end_col: 7,
         bpp: Bpp8,
         flip: False
      });
      check_pixel('h2c);
      check_pixel('h16);
      check_pixel('h0b);
      check_pixel('h8b);
      check_pixel('hcb);
   endseq;

   let test_scrolled_end = seq
      dut.tiles.request.put(TileRequest{
         tile_row_addr: 1,
         start_col: 0,
         end_col: 5,
         bpp: Bpp1,
         flip: False
      });
      check_pixel(1);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(1);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 0,
         end_col: 4,
         bpp: Bpp4,
         flip: False
      });
      check_pixel(4);
      check_pixel(7);
      check_pixel(10);
      check_pixel(13);
      check_pixel(13);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 4,
         start_col: 0,
         end_col: 4,
         bpp: Bpp2,
         flip: False
      });
      check_pixel(3);
      check_pixel(1);
      check_pixel(2);
      check_pixel(0);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 12,
         start_col: 0,
         end_col: 4,
         bpp: Bpp8,
         flip: False
      });
      check_pixel('h7d);
      check_pixel('hb0);
      check_pixel('h58);
      check_pixel('h2c);
      check_pixel('h16);
   endseq;

   let test_flipped_tile = seq
      dut.tiles.request.put(TileRequest{
         tile_row_addr: 1,
         start_col: 0,
         end_col: 7,
         bpp: Bpp1,
         flip: True
      });
      check_pixel(0);
      check_pixel(1);
      check_pixel(1);
      check_pixel(1);
      check_pixel(0);
      check_pixel(0);
      check_pixel(0);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 0,
         end_col: 7,
         bpp: Bpp2,
         flip: True
      });
      check_pixel(1);
      check_pixel(3);
      check_pixel(2);
      check_pixel(2);
      check_pixel(3);
      check_pixel(1);
      check_pixel(0);
      check_pixel(1);

      dut.tiles.request.put(TileRequest{
         tile_row_addr: 2,
         start_col: 1,
         end_col: 5,
         bpp: Bpp2,
         flip: True
      });
      // pixels in VRAM order: 1 0 1 3 2 2 3 1
      // unflipped slice     : _ 0 1 3 2 2 _ _
      // flipped pixels      : 1 3 2 2 3 1 0 1
      // flipped slice       : _ 3 2 2 3 1 _ _
      check_pixel(3);
      check_pixel(2);
      check_pixel(2);
      check_pixel(3);
      check_pixel(1);
   endseq;

   let fsm <- mkFSM(seq
      populate_vram;

      test_basic_render;
      test_stalled_consumer;
      test_scrolled_start;
      test_scrolled_end;
      test_flipped_tile;

      repeat (10) noAction;
   endseq);

   method start = fsm.start;
   method done = fsm.done;
endmodule

module mkTB();
   let test_pxc_to_tsc <- mkTestPixelcoordToTileSubcoord();
   let test_palette_expander <- mkTestPaletteExpander();
   let test_tile_renderer <- mkTestTileRenderer();

   Reg#(Scanline) line <- mkReg(0);
   runTest(2000,
      mkTest("Tiler", seq
         mkTest("Tiler/PixelcoordToTilesubcoord", seq
            test_pxc_to_tsc.start();
            await(test_pxc_to_tsc.done);
         endseq);
         mkTest("Tiler/PaletteExpander", seq
            test_palette_expander.start();
            await(test_palette_expander.done);
         endseq);
         mkTest("Tiler/TileRenderer", seq
            test_tile_renderer.start();
            await(test_tile_renderer.done);
         endseq);
      endseq));
endmodule

endpackage