// Copyright 2026 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <cstdio>
#include <cstdlib>
#include <string>
#include <string_view>
#include <vector>

#include <gtest/gtest.h>

#include "ProbeBroadway.h"
#include "ProbeBudget.h"
#include "staros_h1a.h"
#include "staros_hw0c.h"

namespace StarletBootstrapProbe
{
namespace
{
// StarOS boot/wii/loader/board.h's timebase ticks a millisecond.
constexpr u64 TICKS_PER_MS = 60750;

// PPC memory as the client sees it: the bench window's words, and a count of what fell outside.
class FakeMemory final : public BroadwayMemory
{
public:
  u32 LoadWord(u32 address) override
  {
    if (InBenchWindow(address))
      return words[(address - BENCH_WINDOW_BASE) / 4];
    ++outside;
    return 0;
  }
  void StoreWord(u32 address, u32 word) override
  {
    if (InBenchWindow(address))
      words[(address - BENCH_WINDOW_BASE) / 4] = word;
    else
      ++outside;
  }
  u32& At(u32 offset) { return words[offset / 4]; }

  std::vector<u32> words = std::vector<u32>((BENCH_WINDOW_END - BENCH_WINDOW_BASE) / 4);
  int outside = 0;
};

TEST(StarletProbeBroadway, TheWindowIsTheContractsAndNothingElseIsReached)
{
  EXPECT_EQ(BENCH_WINDOW_BASE, u32{STAROS_HW0C_BASE});
  EXPECT_EQ(BENCH_WINDOW_END, u32{STAROS_HW0C_BASE + STAROS_HW0C_SIZE});
  FakeMemory memory;
  BroadwayHal hal(memory, 100);
  hal.Write(BENCH_WINDOW_BASE, 7);
  hal.Write(BENCH_WINDOW_END - 4, 9);
  EXPECT_EQ(hal.Read(BENCH_WINDOW_BASE), u32{7});
  EXPECT_EQ(hal.Read(BENCH_WINDOW_END - 4), u32{9});
  hal.CacheLine(BENCH_WINDOW_BASE + 0x20);
  EXPECT_FALSE(hal.Failed());
  EXPECT_EQ(hal.Accesses(), u64{5});

  // The first access outside fails the client, and is never made.
  EXPECT_EQ(hal.Read(BENCH_WINDOW_END), u32{0});
  EXPECT_TRUE(hal.Failed());
  EXPECT_EQ(hal.Failure(), "a read at 0x13510000, outside the bench window 0x13500000..0x13510000");
  hal.Write(BENCH_WINDOW_BASE - 4, 1);
  hal.Write(BENCH_WINDOW_BASE + 2, 1);
  EXPECT_EQ(memory.outside, 0);
  EXPECT_EQ(hal.Failure(), "a read at 0x13510000, outside the bench window 0x13500000..0x13510000");
  EXPECT_FALSE(InBenchWindow(BENCH_WINDOW_BASE + 2));
  EXPECT_FALSE(InBenchWindow(0x135E0000));
  EXPECT_FALSE(InBenchWindow(u64{BENCH_WINDOW_BASE} + 0x100000000));
}

TEST(StarletProbeBroadway, TheTimebaseIsAQuarterOfTheStarletsCycles)
{
  FakeMemory memory;
  BroadwayHal hal(memory, CLIENT_TIMEBASE_BASE);
  hal.Elapse(0);
  EXPECT_EQ(hal.Timebase(), CLIENT_TIMEBASE_BASE);
  hal.Elapse(SLICE_CYCLES);
  EXPECT_EQ(hal.Timebase(), CLIENT_TIMEBASE_BASE + 1024);
  // 2 ms of Broadway's timebase (StarOS's TICKS_PER_MS, 60750) is 486,000 Starlet cycles.
  hal.Elapse(486000);
  EXPECT_EQ(hal.Timebase() - CLIENT_TIMEBASE_BASE - 1024, u64{121500});
}

TEST(StarletProbeBroadway, TheCaptureIsGeckosFormats)
{
  FakeMemory memory;
  BroadwayHal hal(memory, 0);
  hal.Put("SBL:X ");
  hal.Hex(0x1A);
  hal.Put(" ");
  hal.Dec(0);
  hal.Put(" ");
  hal.Dec(0xFFFFFFFF);
  hal.Put(" ");
  hal.Hex(0xDEADBEEF);
  EXPECT_EQ(hal.Capture(), "SBL:X 0x0000001a 0 4294967295 0xdeadbeef");
}

TEST(StarletProbeBroadway, TheClientsBudgetIsBoundedAndOnlyItsOwn)
{
  EXPECT_EQ(MAX_CLIENT_CYCLES, u64{1} << 34);
  EXPECT_EQ(ParseCycles("17179869184", MAX_CLIENT_CYCLES), MAX_CLIENT_CYCLES);
  EXPECT_FALSE(ParseCycles("17179873280", MAX_CLIENT_CYCLES));
  EXPECT_FALSE(ParseCycles("17179869185", MAX_CLIENT_CYCLES));
  // Without the client, 2^30 as before.
  EXPECT_EQ(ParseCycles("1073741824"), MAX_CYCLES);
  EXPECT_FALSE(ParseCycles("1073745920"));
  EXPECT_FALSE(ParseCycles("17179869184"));
}

TEST(StarletProbeBroadway, OnlyTheOptionItselfRaisesTheBudget)
{
  const auto requested = [](std::vector<const char*> argv) {
    return ClientRequested(static_cast<int>(argv.size()), argv.data());
  };
  EXPECT_TRUE(requested({"probe", "image.elf", "--broadway-h1a"}));
  EXPECT_TRUE(requested({"probe", "image.elf", "--jit", "--cycles", "4096", "--broadway-h1a"}));
  EXPECT_TRUE(requested({"probe", "image.elf", "--stage-spk", "p.bin", "--broadway-h1a"}));
  EXPECT_FALSE(requested({"probe", "image.elf"}));
  // The image's own name, or another option's value, is no option.
  EXPECT_FALSE(requested({"probe", "--broadway-h1a"}));
  EXPECT_FALSE(requested({"probe", "image.elf", "--ipc-script", "--broadway-h1a"}));
  EXPECT_FALSE(requested({"probe", "image.elf", "--stage-spk", "--broadway-h1a", "--jit"}));
  EXPECT_FALSE(requested({"probe", "image.elf", "--cycles", "--broadway-h1a"}));
}

TEST(StarletProbeBroadway, TheStarletIsDoneAsTheLoadersMonitorSaysIt)
{
  // StarOS boot/contract/staros_boot.h: RUNNING 2, IDLE 3, FATAL 4, PANIC 5, FAULT 6; EXI PPC 1.
  EXPECT_EQ(SBR1_STATE_IDLE, u32{3});
  EXPECT_TRUE(StarletDone(false, 3, SBR1_EXI_PPC));
  EXPECT_TRUE(StarletDone(false, 6, SBR1_EXI_PPC));
  EXPECT_FALSE(StarletDone(false, 2, SBR1_EXI_PPC));
  EXPECT_FALSE(StarletDone(false, 3, SBR1_EXI_STARLET));
  EXPECT_FALSE(StarletDone(false, 0, 0));
  // A terminal trace line counts on its own.
  EXPECT_TRUE(StarletDone(true, 0, 0));
}

TEST(StarletProbeBroadway, TheBuiltInSourcesAreTheNineFilesWithTheirHashes)
{
  const std::string_view sources = BroadwayClient::Sources();
  const char* names[] = {"hw0c.c", "hw0c.h", "hw0d.c", "hw0d.h", "h1a.c",
                         "h1a.h",  "staros_hw0c.h", "staros_hw0d.h", "staros_h1a.h"};
  size_t at = 0;
  for (const char* name : names)
  {
    const size_t end = sources.find('\n', at);
    ASSERT_NE(end, std::string_view::npos);
    const std::string_view line = sources.substr(at, end - at);
    EXPECT_TRUE(line.starts_with(std::string(name) + " ")) << line;
    EXPECT_EQ(line.size(), std::string_view(name).size() + 1 + 64) << line;
    at = end + 1;
  }
  EXPECT_EQ(at, sources.size());
}

// A scripted Starlet over the fake window, as StarOS's tests/hardware-wii/h1a benches script it:
// READY 100 ms after the first step (unless `ready` is false), then each round answered at least
// 40,960 timebase ticks after it was first seen posted, S2B's words first for a Starlet -> Broadway
// round; after the last round or Broadway's END, its record (GEN 2) and its END (unless `ends` is
// false).
struct Starlet
{
  bool ready = true;
  bool ends = true;
  bool answered_ready = false;
  bool ended = false;
  u32 answered = 0;
  bool seen = false;
  u64 seen_at = 0;

  static u32 Scenario(u32 round) { return round <= STAROS_H1A_S1_ROUNDS ? STAROS_H1A_S1 : STAROS_H1A_S3; }

  void Tick(FakeMemory& memory, u64 now, u64 start)
  {
    const u32 broadway = STAROS_HW0C_BROADWAY, starlet = STAROS_HW0C_STARLET;
    if (!answered_ready)
    {
      if (ready && now >= start + 100 * TICKS_PER_MS)
      {
        answered_ready = true;
        memory.At(STAROS_HW0C_ENVIRONMENT + STAROS_HW0C_E_CONTROL) = 0x000520FB;
        memory.At(STAROS_HW0C_ENVIRONMENT + STAROS_HW0C_E_DACR) = 1;
        memory.At(STAROS_HW0C_ENVIRONMENT + STAROS_HW0C_E_DESCRIPTOR) = 0x13500552;
        memory.At(STAROS_HW0C_ENVIRONMENT + STAROS_HW0C_E_SENTINEL_BAD) = 0;
        memory.At(starlet + STAROS_HW0C_C_STATE) = STAROS_HW0C_STATE_READY;
      }
      return;
    }
    if (ended)
      return;
    if (answered == STAROS_H1A_ROUNDS ||
        memory.At(broadway + STAROS_HW0C_C_STATE) == STAROS_HW0C_STATE_END)
    {
      if (!ends)
        return;
      for (u32 i = 0; i < STAROS_H1A_RESULTS_WORDS; ++i)
        memory.At(STAROS_H1A_RESULTS + 4 * i) = 0x1000 + i;
      memory.At(STAROS_H1A_RESULTS + 4 * STAROS_H1A_F_MAGIC) = STAROS_H1A_MAGIC;
      memory.At(STAROS_H1A_RESULTS + 4 * STAROS_H1A_F_VERSION) = STAROS_H1A_VERSION;
      memory.At(STAROS_H1A_RESULTS + 4 * STAROS_H1A_F_GEN) = STAROS_H1A_GEN;
      memory.At(starlet + STAROS_HW0C_C_STATE) = STAROS_HW0C_STATE_END;
      ended = true;
      return;
    }
    const u32 round = answered + 1;
    if (memory.At(broadway + STAROS_HW0C_C_STATE) != STAROS_HW0C_STATE_ROUND ||
        memory.At(broadway + STAROS_HW0C_C_ROUND) != round ||
        memory.At(broadway + STAROS_HW0C_C_SCENARIO) != Scenario(round))
    {
      return;
    }
    if (!seen)
    {
      seen = true;
      seen_at = now;
    }
    if (now - seen_at < 40960)
      return;
    const bool s2b = round > STAROS_H1A_S1_ROUNDS && (round - STAROS_H1A_S1_ROUNDS) % 2 == 0;
    if (s2b)
    {
      for (u32 w = 0; w < STAROS_H1A_AREA_WORDS; ++w)
      {
        const u32 offset = STAROS_H1A_S2B + 4 * w;
        memory.At(offset) = STAROS_HW0C_PATTERN(STAROS_HW0C_TAG_S2B, round, offset / 4);
      }
    }
    memory.At(starlet + STAROS_HW0C_C_SCENARIO) = Scenario(round);
    memory.At(starlet + STAROS_HW0C_C_STATE) = STAROS_HW0C_STATE_ROUND;
    memory.At(starlet + STAROS_HW0C_C_ROUND) = round;
    answered = round;
    seen = false;
  }
};

// One whole run of the real loader code in this process (its state is global: each death test's
// child runs it alone). Its report goes to stderr; the child exits 0 only if the run ended (or not)
// as `done` says, reached nothing outside the window, held every line of `required` in its report,
// and a second client in the same process was refused. (Windows' gtest has only simple regular
// expressions, so the child checks the report itself.)
[[noreturn]] void RunClient(Starlet starlet, u64 slices, bool done,
                            std::vector<std::string_view> required)
{
  FakeMemory memory;
  BroadwayClient client;
  if (!client.Start(memory))
    std::exit(2);
  const u64 start = client.Timebase();
  for (u64 slice = 0; slice < slices && !client.Done() && !client.Failed(); ++slice)
  {
    starlet.Tick(memory, client.Timebase(), start);
    client.Advance(slice == 0 ? 0 : SLICE_CYCLES);
  }
  const std::string report =
      client.Report(client.Done() ? CLIENT_STATUS_DONE : CLIENT_STATUS_TIMEOUT);
  std::fputs(report.c_str(), stderr);
  int missing = 0;
  for (const std::string_view line : required)
  {
    if (report.find(line) == std::string::npos)
    {
      std::fprintf(stderr, "MISSING %.*s\n", static_cast<int>(line.size()), line.data());
      ++missing;
    }
  }
  BroadwayClient second;
  FakeMemory other;
  const bool refused = !second.Start(other) && second.Failed();
  std::fprintf(stderr, "steps %llu outside %d failed %d done %d refused %d missing %d\n",
               static_cast<unsigned long long>(client.Steps()), memory.outside,
               static_cast<int>(client.Failed()), static_cast<int>(client.Done()),
               static_cast<int>(refused), missing);
  const bool passed = client.Done() == done && !client.Failed() && memory.outside == 0 &&
                      refused && missing == 0;
  std::exit(passed ? 0 : 1);
}

// Enough slices for 3000 rounds of at least 2 ms each, and the waits: 2^34 cycles' worth.
constexpr u64 SLICES = MAX_CLIENT_CYCLES / SLICE_CYCLES;

TEST(StarletProbeBroadwayDeathTest, TheRealLoaderRunsAllRoundsAndReports)
{
  EXPECT_EXIT(RunClient(Starlet{}, SLICES, true,
                        {"SBL:STARLET DONE\n", "SBL:HW0C S0 PASS\n",
                         "SBL:H1A B POSTS 3000 LAST 3000 ACKS 3000 TIMEOUT 0 ",
                         "SBL:H1A B CHECK SENTINEL 0 SCRUB 0 POOL 0\n",
                         "SBL:H1A S GEN 0x00000002 0x00000002 ATTEMPTS 1 COHERENT\n",
                         "SBL:H1A END CRC 0x", "\nSBL:END GECKO DROPPED AFTER JUMP 0 BEFORE 0\n"}),
              ::testing::ExitedWithCode(0), "");
}

TEST(StarletProbeBroadwayDeathTest, WithoutReadyTheBenchTimesOutAndNeverStartsH1A)
{
  Starlet starlet;
  starlet.ready = false;
  EXPECT_EXIT(RunClient(starlet, SLICES, true,
                        {"SBL:HW0C S0 INCONCLUSIVE\n", "SBL:HW0C TIMEOUT S0 ROUND 0\n",
                         "SBL:H1A B POSTS 0 LAST 0 ACKS 0 ", "ATTEMPTS 3 INCOMPLETE\n"}),
              ::testing::ExitedWithCode(0), "");
}

TEST(StarletProbeBroadwayDeathTest, WithoutTheStarletsEndBroadwayStopsAtReadyPlus65s)
{
  Starlet starlet;
  starlet.ends = false;
  EXPECT_EXIT(RunClient(starlet, SLICES, true,
                        {"SBL:HW0C S0 INCONCLUSIVE\n", "SBL:HW0C TIMEOUT S0 ROUND 0\n",
                         "SBL:H1A B POSTS 3000 LAST 3000 ", "ATTEMPTS 3 INCOMPLETE\n"}),
              ::testing::ExitedWithCode(0), "");
}

TEST(StarletProbeBroadwayDeathTest, ABudgetTooShortEndsUnderTimeout)
{
  EXPECT_EXIT(RunClient(Starlet{}, 1000, false,
                        {"SBL:TIMEOUT\n", "SBL:END GECKO DROPPED AFTER JUMP 0 BEFORE 0\n"}),
              ::testing::ExitedWithCode(0), "");
}
}  // namespace
}  // namespace StarletBootstrapProbe