// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This file contains the tests for the RingBuffer class.

#include "gpu/command_buffer/client/ring_buffer.h"

#include "base/bind.h"
#include "base/bind_helpers.h"
#include "gpu/command_buffer/client/cmd_buffer_helper.h"
#include "gpu/command_buffer/service/cmd_buffer_engine.h"
#include "gpu/command_buffer/service/command_buffer_service.h"
#include "gpu/command_buffer/service/gpu_scheduler.h"
#include "gpu/command_buffer/service/mocks.h"
#include "gpu/command_buffer/service/transfer_buffer_manager.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace gpu {

using testing::Return;
using testing::Mock;
using testing::Truly;
using testing::Sequence;
using testing::DoAll;
using testing::Invoke;
using testing::_;

class BaseRingBufferTest : public testing::Test {
 protected:
  static const unsigned int kBaseOffset = 128;
  static const unsigned int kBufferSize = 1024;
  static const unsigned int kAlignment = 4;

  void RunPendingSetToken() {
    for (std::vector<const void*>::iterator it = set_token_arguments_.begin();
         it != set_token_arguments_.end();
         ++it) {
      api_mock_->SetToken(cmd::kSetToken, 1, *it);
    }
    set_token_arguments_.clear();
    delay_set_token_ = false;
  }

  void SetToken(unsigned int command,
                unsigned int arg_count,
                const void* _args) {
    EXPECT_EQ(static_cast<unsigned int>(cmd::kSetToken), command);
    EXPECT_EQ(1u, arg_count);
    if (delay_set_token_)
      set_token_arguments_.push_back(_args);
    else
      api_mock_->SetToken(cmd::kSetToken, 1, _args);
  }

  void SetUp() override {
    delay_set_token_ = false;
    api_mock_.reset(new AsyncAPIMock(true));
    // ignore noops in the mock - we don't want to inspect the internals of the
    // helper.
    EXPECT_CALL(*api_mock_, DoCommand(cmd::kNoop, 0, _))
        .WillRepeatedly(Return(error::kNoError));
    // Forward the SetToken calls to the engine
    EXPECT_CALL(*api_mock_.get(), DoCommand(cmd::kSetToken, 1, _))
        .WillRepeatedly(DoAll(Invoke(this, &BaseRingBufferTest::SetToken),
                              Return(error::kNoError)));

    {
      TransferBufferManager* manager = new TransferBufferManager();
      transfer_buffer_manager_.reset(manager);
      EXPECT_TRUE(manager->Initialize());
    }
    command_buffer_.reset(
        new CommandBufferService(transfer_buffer_manager_.get()));
    EXPECT_TRUE(command_buffer_->Initialize());

    gpu_scheduler_.reset(new GpuScheduler(
        command_buffer_.get(), api_mock_.get(), NULL));
    command_buffer_->SetPutOffsetChangeCallback(base::Bind(
        &GpuScheduler::PutChanged, base::Unretained(gpu_scheduler_.get())));
    command_buffer_->SetGetBufferChangeCallback(base::Bind(
        &GpuScheduler::SetGetBuffer, base::Unretained(gpu_scheduler_.get())));

    api_mock_->set_engine(gpu_scheduler_.get());

    helper_.reset(new CommandBufferHelper(command_buffer_.get()));
    helper_->Initialize(kBufferSize);
  }

  int32 GetToken() {
    return command_buffer_->GetLastState().token;
  }

  scoped_ptr<AsyncAPIMock> api_mock_;
  scoped_ptr<TransferBufferManagerInterface> transfer_buffer_manager_;
  scoped_ptr<CommandBufferService> command_buffer_;
  scoped_ptr<GpuScheduler> gpu_scheduler_;
  scoped_ptr<CommandBufferHelper> helper_;
  std::vector<const void*> set_token_arguments_;
  bool delay_set_token_;

  scoped_ptr<int8[]> buffer_;
  int8* buffer_start_;
};

#ifndef _MSC_VER
const unsigned int BaseRingBufferTest::kBaseOffset;
const unsigned int BaseRingBufferTest::kBufferSize;
#endif

// Test fixture for RingBuffer test - Creates a RingBuffer, using a
// CommandBufferHelper with a mock AsyncAPIInterface for its interface (calling
// it directly, not through the RPC mechanism), making sure Noops are ignored
// and SetToken are properly forwarded to the engine.
class RingBufferTest : public BaseRingBufferTest {
 protected:
  void SetUp() override {
    BaseRingBufferTest::SetUp();

    buffer_.reset(new int8[kBufferSize + kBaseOffset]);
    buffer_start_ = buffer_.get() + kBaseOffset;
    allocator_.reset(new RingBuffer(kAlignment, kBaseOffset, kBufferSize,
                                    helper_.get(), buffer_start_));
  }

  void TearDown() override {
    // If the GpuScheduler posts any tasks, this forces them to run.
    base::MessageLoop::current()->RunUntilIdle();

    BaseRingBufferTest::TearDown();
  }

  scoped_ptr<RingBuffer> allocator_;
};

// Checks basic alloc and free.
TEST_F(RingBufferTest, TestBasic) {
  const unsigned int kSize = 16;
  EXPECT_EQ(kBufferSize, allocator_->GetLargestFreeOrPendingSize());
  EXPECT_EQ(kBufferSize, allocator_->GetLargestFreeSizeNoWaiting());
  void* pointer = allocator_->Alloc(kSize);
  EXPECT_GE(kBufferSize, allocator_->GetOffset(pointer) - kBaseOffset + kSize);
  EXPECT_EQ(kBufferSize, allocator_->GetLargestFreeOrPendingSize());
  EXPECT_EQ(kBufferSize - kSize, allocator_->GetLargestFreeSizeNoWaiting());
  int32 token = helper_->InsertToken();
  allocator_->FreePendingToken(pointer, token);
}

// Checks the free-pending-token mechanism.
TEST_F(RingBufferTest, TestFreePendingToken) {
  const unsigned int kSize = 16;
  const unsigned int kAllocCount = kBufferSize / kSize;
  CHECK(kAllocCount * kSize == kBufferSize);

  delay_set_token_ = true;
  // Allocate several buffers to fill in the memory.
  int32 tokens[kAllocCount];
  for (unsigned int ii = 0; ii < kAllocCount; ++ii) {
    void* pointer = allocator_->Alloc(kSize);
    EXPECT_GE(kBufferSize,
              allocator_->GetOffset(pointer) - kBaseOffset + kSize);
    tokens[ii] = helper_->InsertToken();
    allocator_->FreePendingToken(pointer, tokens[ii]);
  }

  EXPECT_EQ(kBufferSize - (kSize * kAllocCount),
            allocator_->GetLargestFreeSizeNoWaiting());

  RunPendingSetToken();

  // This allocation will need to reclaim the space freed above, so that should
  // process the commands until a token is passed.
  void* pointer1 = allocator_->Alloc(kSize);
  EXPECT_EQ(kBaseOffset, allocator_->GetOffset(pointer1));

  // Check that the token has indeed passed.
  EXPECT_LE(tokens[0], GetToken());

  allocator_->FreePendingToken(pointer1, helper_->InsertToken());
}

// Tests GetLargestFreeSizeNoWaiting
TEST_F(RingBufferTest, TestGetLargestFreeSizeNoWaiting) {
  EXPECT_EQ(kBufferSize, allocator_->GetLargestFreeSizeNoWaiting());

  void* pointer = allocator_->Alloc(kBufferSize);
  EXPECT_EQ(0u, allocator_->GetLargestFreeSizeNoWaiting());
  allocator_->FreePendingToken(pointer, helper_->InsertToken());
}

TEST_F(RingBufferTest, TestFreeBug) {
  // The first and second allocations must not match.
  const unsigned int kAlloc1 = 3*kAlignment;
  const unsigned int kAlloc2 = 20;
  void* pointer = allocator_->Alloc(kAlloc1);
  EXPECT_EQ(kBufferSize - kAlloc1, allocator_->GetLargestFreeSizeNoWaiting());
  allocator_->FreePendingToken(pointer, helper_.get()->InsertToken());
  pointer = allocator_->Alloc(kAlloc2);
  EXPECT_EQ(kBufferSize - kAlloc1 - kAlloc2,
            allocator_->GetLargestFreeSizeNoWaiting());
  allocator_->FreePendingToken(pointer, helper_.get()->InsertToken());
  pointer = allocator_->Alloc(kBufferSize);
  EXPECT_EQ(0u, allocator_->GetLargestFreeSizeNoWaiting());
  allocator_->FreePendingToken(pointer, helper_.get()->InsertToken());
}

}  // namespace gpu