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

#include "device/gamepad/gamepad_provider.h"

#include <memory>

#include "base/command_line.h"
#include "base/compiler_specific.h"
#include "base/functional/bind.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/run_loop.h"
#include "base/test/scoped_feature_list.h"
#include "base/threading/platform_thread.h"
#include "base/threading/thread.h"
#include "build/build_config.h"
#include "device/gamepad/gamepad_data_fetcher.h"
#include "device/gamepad/gamepad_test_helpers.h"
#include "device/gamepad/public/cpp/gamepad_features.h"
#include "device/gamepad/public/cpp/gamepad_switches.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace device {

namespace {

constexpr int64_t kInitialTimeStamp = 0;
constexpr int64_t kUserGestureTimeStamp = 1;
constexpr int64_t kPollTimeStamp = 2;

// Helper class to generate and record user gesture callbacks.
class UserGestureListener {
 public:
  UserGestureListener() : has_user_gesture_(false) {}

  base::OnceClosure GetClosure() {
    return base::BindOnce(&UserGestureListener::GotUserGesture,
                          weak_factory_.GetWeakPtr());
  }

  void WaitForUserGesture() {
    if (has_user_gesture_) {
      return;
    }

    base::RunLoop run_loop;
    quit_closure_ = run_loop.QuitClosure();
    run_loop.Run();
  }

  bool has_user_gesture() const { return has_user_gesture_; }

 private:
  void GotUserGesture() {
    has_user_gesture_ = true;
    if (quit_closure_) {
      std::move(quit_closure_).Run();
    }
  }

  bool has_user_gesture_;
  base::OnceClosure quit_closure_;
  base::WeakPtrFactory<UserGestureListener> weak_factory_{this};
};

// Main test fixture
class GamepadProviderTest : public testing::Test, public GamepadTestHelper {
 public:
  GamepadProviderTest(const GamepadProviderTest&) = delete;
  GamepadProviderTest& operator=(const GamepadProviderTest&) = delete;

  GamepadProvider* CreateProvider(const Gamepads& test_data) {
    auto fetcher = std::make_unique<MockGamepadDataFetcher>(test_data);
    mock_data_fetcher_ = fetcher.get();
    provider_ = std::make_unique<GamepadProvider>(
        /*gamepad_change_client=*/nullptr, std::move(fetcher),
        /*polling_thread=*/nullptr);
    return provider_.get();
  }

  // Sleep until the shared memory buffer's seqlock advances the buffer version,
  // indicating that the gamepad provider has written to it after polling the
  // gamepad fetchers. The buffer will report an odd value for the version if
  // the buffer is not in a consistent state, so we also require that the value
  // is even before continuing.
  void WaitForData(const GamepadHardwareBuffer* buffer) {
    const int32_t initial_version = buffer->seqlock.ReadBegin();
    int32_t current_version;
    do {
      base::PlatformThread::Sleep(base::Milliseconds(10));
      current_version = buffer->seqlock.ReadBegin();
    } while (current_version % 2 || current_version == initial_version);
  }

  // The provider polls the data on the background thread and then issues
  // the callback on the client thread. Waiting for it to poll twice ensures
  // that it was able to issue callbacks for the first poll.
  void WaitForDataAndCallbacksIssued(const GamepadHardwareBuffer* buffer) {
    WaitForData(buffer);
    WaitForData(buffer);
  }

  void ReadGamepadHardwareBuffer(const GamepadHardwareBuffer* buffer,
                                 Gamepads* output) {
    UNSAFE_TODO(memset(output, 0, sizeof(Gamepads)));
    int32_t version;
    do {
      version = buffer->seqlock.ReadBegin();
      UNSAFE_TODO(memcpy(output, &buffer->data, sizeof(Gamepads)));
    } while (buffer->seqlock.ReadRetry(version));
  }

  void EnableRawInputChangeDetection() {
    scoped_feature_list_.InitAndEnableFeature(
        features::kGamepadRawInputChangeEvent);
  }

  void SetInitialStateForRawInputChange(Gamepads& data, int64_t timestamp) {
    data.items[0] = {};
    data.items[0].connected = true;
    data.items[0].timestamp = timestamp;
    data.items[0].buttons_length = 4;
    data.items[0].axes_length = 2;
    data.items[0].touch_events_length = 2;
    data.items[0].supports_touch_events_ = true;
    data.items[0].touch_events[0].touch_id = 1;
    data.items[0].touch_events[1].touch_id = 2;
  }

  void SetUserGestureForRawInputChange(Gamepads& data, int64_t timestamp) {
    // Always set the first button as pressed for user gesture.
    data.items[0].timestamp = timestamp;
    data.items[0].buttons[0].value = 1.0f;
    data.items[0].buttons[0].pressed = true;
  }

  // Helper method to test raw input change detection for different input types.
  void TestRawInputChangeDetection(
      const std::string& test_name,
      base::OnceCallback<void(Gamepads&)> setup_input_change_data,
      base::OnceCallback<void(const Gamepads&)> verify_final_state) {
    // Setup initial gamepad state.
    Gamepads test_data = {};
    SetInitialStateForRawInputChange(test_data, kInitialTimeStamp);
    GamepadProvider* provider = CreateProvider(test_data);
    provider->SetSanitizationEnabled(false);
    provider->Resume();

    UserGestureListener listener;
    provider->RegisterForUserGesture(listener.GetClosure());

    // Get shared memory buffer.
    base::ReadOnlySharedMemoryRegion region =
        provider->DuplicateSharedMemoryRegion();
    base::ReadOnlySharedMemoryMapping mapping = region.Map();
    EXPECT_TRUE(mapping.IsValid());
    const GamepadHardwareBuffer* buffer =
        static_cast<const GamepadHardwareBuffer*>(mapping.memory());

    // Wait for initial data and verify no input change detected yet.
    WaitForData(buffer);
    EXPECT_FALSE(provider->HasInputChangedForTesting())
        << "Initial state should show no input change for " << test_name;

    // Trigger user gesture.
    Gamepads user_gesture_data = test_data;
    SetUserGestureForRawInputChange(user_gesture_data, kUserGestureTimeStamp);
    mock_data_fetcher_->SetTestData(user_gesture_data);
    WaitForDataAndCallbacksIssued(buffer);
    listener.WaitForUserGesture();

    EXPECT_TRUE(listener.has_user_gesture())
        << "User gesture should be detected for " << test_name;

    // Setup input change data (the actual change we want to test).
    Gamepads input_change_data = user_gesture_data;
    input_change_data.items[0].timestamp = kPollTimeStamp;
    std::move(setup_input_change_data).Run(input_change_data);

    // Apply the input change that should be detected.
    mock_data_fetcher_->SetTestData(input_change_data);
    WaitForDataAndCallbacksIssued(buffer);

    // Verify the result.
    Gamepads output;
    ReadGamepadHardwareBuffer(buffer, &output);
    std::move(verify_final_state).Run(output);

    if (user_gesture_data.items[0].timestamp !=
        input_change_data.items[0].timestamp) {
      EXPECT_TRUE(provider->HasInputChangedForTesting())
          << "Input change should be detected for " << test_name;
    } else {
      EXPECT_FALSE(provider->HasInputChangedForTesting())
          << "Input change should NOT be detected for " << test_name;
    }
  }

 protected:
  GamepadProviderTest() = default;

  base::test::ScopedFeatureList scoped_feature_list_;

  std::unique_ptr<GamepadProvider> provider_;

  // Pointer owned by the provider.
  raw_ptr<MockGamepadDataFetcher> mock_data_fetcher_;
};

TEST_F(GamepadProviderTest, PollingAccess) {
  Gamepads test_data;
  UNSAFE_TODO(memset(&test_data, 0, sizeof(Gamepads)));
  test_data.items[0].connected = true;
  test_data.items[0].timestamp = 0;
  test_data.items[0].buttons_length = 1;
  test_data.items[0].axes_length = 2;
  test_data.items[0].buttons[0].value = 1.0f;
  test_data.items[0].buttons[0].pressed = true;
  test_data.items[0].axes[0] = -1.0f;
  test_data.items[0].axes[1] = 0.5f;

  GamepadProvider* provider = CreateProvider(test_data);
  provider->SetSanitizationEnabled(false);
  provider->Resume();

  base::RunLoop().RunUntilIdle();

  // Renderer-side, pull data out of poll buffer.
  base::ReadOnlySharedMemoryRegion region =
      provider->DuplicateSharedMemoryRegion();
  base::ReadOnlySharedMemoryMapping mapping = region.Map();
  EXPECT_TRUE(mapping.IsValid());

  const GamepadHardwareBuffer* buffer =
      static_cast<const GamepadHardwareBuffer*>(mapping.memory());

  // Wait until the shared memory buffer has been written at least once.
  WaitForData(buffer);

  Gamepads output;
  ReadGamepadHardwareBuffer(buffer, &output);

  ASSERT_EQ(1u, output.items[0].buttons_length);
  EXPECT_EQ(1.0f, output.items[0].buttons[0].value);
  EXPECT_EQ(true, output.items[0].buttons[0].pressed);
  ASSERT_EQ(2u, output.items[0].axes_length);
  EXPECT_EQ(-1.0f, output.items[0].axes[0]);
  EXPECT_EQ(0.5f, output.items[0].axes[1]);
}

TEST_F(GamepadProviderTest, ConnectDisconnectMultiple) {
  Gamepads test_data;
  test_data.items[0].connected = true;
  test_data.items[0].timestamp = 0;
  test_data.items[0].axes_length = 2;
  test_data.items[0].axes[0] = -1.0f;
  test_data.items[0].axes[1] = 0.5f;

  test_data.items[1].connected = true;
  test_data.items[1].timestamp = 0;
  test_data.items[1].axes_length = 2;
  test_data.items[1].axes[0] = 1.0f;
  test_data.items[1].axes[1] = -0.5f;

  Gamepads test_data_onedisconnected;
  test_data_onedisconnected.items[1].connected = true;
  test_data_onedisconnected.items[1].timestamp = 0;
  test_data_onedisconnected.items[1].axes_length = 2;
  test_data_onedisconnected.items[1].axes[0] = 1.0f;
  test_data_onedisconnected.items[1].axes[1] = -0.5f;

  GamepadProvider* provider = CreateProvider(test_data);
  provider->SetSanitizationEnabled(false);
  provider->Resume();

  base::RunLoop().RunUntilIdle();

  // Renderer-side, pull data out of poll buffer.
  base::ReadOnlySharedMemoryRegion region =
      provider->DuplicateSharedMemoryRegion();
  base::ReadOnlySharedMemoryMapping mapping = region.Map();
  EXPECT_TRUE(mapping.IsValid());

  const GamepadHardwareBuffer* buffer =
      static_cast<const GamepadHardwareBuffer*>(mapping.memory());

  // Wait until the shared memory buffer has been written at least once.
  WaitForData(buffer);

  Gamepads output;
  ReadGamepadHardwareBuffer(buffer, &output);

  ASSERT_EQ(2u, output.items[0].axes_length);
  EXPECT_EQ(-1.0f, output.items[0].axes[0]);
  EXPECT_EQ(0.5f, output.items[0].axes[1]);
  ASSERT_EQ(2u, output.items[1].axes_length);
  EXPECT_EQ(1.0f, output.items[1].axes[0]);
  EXPECT_EQ(-0.5f, output.items[1].axes[1]);

  mock_data_fetcher_->SetTestData(test_data_onedisconnected);

  WaitForDataAndCallbacksIssued(buffer);

  ReadGamepadHardwareBuffer(buffer, &output);

  EXPECT_EQ(0u, output.items[0].axes_length);
  ASSERT_EQ(2u, output.items[1].axes_length);
  EXPECT_EQ(1.0f, output.items[1].axes[0]);
  EXPECT_EQ(-0.5f, output.items[1].axes[1]);
}

// Tests that waiting for a user gesture works properly.
TEST_F(GamepadProviderTest, UserGesture) {
  Gamepads no_button_data;
  no_button_data.items[0].connected = true;
  no_button_data.items[0].timestamp = 0;
  no_button_data.items[0].buttons_length = 1;
  no_button_data.items[0].axes_length = 2;
  no_button_data.items[0].buttons[0].value = 0.0f;
  no_button_data.items[0].buttons[0].pressed = false;
  no_button_data.items[0].axes[0] = 0.0f;
  no_button_data.items[0].axes[1] = 0.4f;

  Gamepads button_down_data = no_button_data;
  button_down_data.items[0].buttons[0].value = 1.0f;
  button_down_data.items[0].buttons[0].pressed = true;

  UserGestureListener listener;
  GamepadProvider* provider = CreateProvider(no_button_data);
  provider->SetSanitizationEnabled(false);
  provider->Resume();

  provider->RegisterForUserGesture(listener.GetClosure());

  base::RunLoop().RunUntilIdle();

  // Renderer-side, pull data out of poll buffer.
  base::ReadOnlySharedMemoryRegion region =
      provider->DuplicateSharedMemoryRegion();
  base::ReadOnlySharedMemoryMapping mapping = region.Map();
  EXPECT_TRUE(mapping.IsValid());

  const GamepadHardwareBuffer* buffer =
      static_cast<const GamepadHardwareBuffer*>(mapping.memory());

  // Wait until the shared memory buffer has been written at least once.
  WaitForData(buffer);

  // It should not have issued our callback.
  EXPECT_FALSE(listener.has_user_gesture());

  // Set a button down.
  mock_data_fetcher_->SetTestData(button_down_data);

  // The user gesture listener callback is not called until after the buffer has
  // been updated. Wait for the second update to ensure callbacks have fired.
  WaitForDataAndCallbacksIssued(buffer);

  // It should have issued our callback.
  base::RunLoop().RunUntilIdle();
  EXPECT_TRUE(listener.has_user_gesture());
}

// Tests that waiting for a user gesture works properly.
TEST_F(GamepadProviderTest, Sanitization) {
  Gamepads active_data;
  active_data.items[0].connected = true;
  active_data.items[0].timestamp = 0;
  active_data.items[0].buttons_length = 1;
  active_data.items[0].axes_length = 1;
  active_data.items[0].buttons[0].value = 1.0f;
  active_data.items[0].buttons[0].pressed = true;
  active_data.items[0].axes[0] = -1.0f;

  Gamepads zero_data;
  zero_data.items[0].connected = true;
  zero_data.items[0].timestamp = 0;
  zero_data.items[0].buttons_length = 1;
  zero_data.items[0].axes_length = 1;
  zero_data.items[0].buttons[0].value = 0.0f;
  zero_data.items[0].buttons[0].pressed = false;
  zero_data.items[0].axes[0] = 0.0f;

  UserGestureListener listener;
  GamepadProvider* provider = CreateProvider(active_data);
  provider->SetSanitizationEnabled(true);
  provider->Resume();

  base::RunLoop().RunUntilIdle();

  // Renderer-side, pull data out of poll buffer.
  base::ReadOnlySharedMemoryRegion region =
      provider->DuplicateSharedMemoryRegion();
  base::ReadOnlySharedMemoryMapping mapping = region.Map();
  ASSERT_TRUE(mapping.IsValid());

  const GamepadHardwareBuffer* buffer =
      static_cast<const GamepadHardwareBuffer*>(mapping.memory());

  // Wait until the shared memory buffer has been written at least once.
  WaitForData(buffer);

  Gamepads output;
  ReadGamepadHardwareBuffer(buffer, &output);

  // Initial data should all be zeroed out due to sanitization, even though the
  // gamepad reported input
  ASSERT_EQ(1u, output.items[0].buttons_length);
  EXPECT_EQ(0.0f, output.items[0].buttons[0].value);
  EXPECT_FALSE(output.items[0].buttons[0].pressed);
  ASSERT_EQ(1u, output.items[0].axes_length);
  EXPECT_EQ(0.0f, output.items[0].axes[0]);

  // Zero out the inputs
  mock_data_fetcher_->SetTestData(zero_data);

  WaitForDataAndCallbacksIssued(buffer);

  // Read updated data from shared memory
  ReadGamepadHardwareBuffer(buffer, &output);

  // Should still read zero, which is now an accurate reflection of the data
  ASSERT_EQ(1u, output.items[0].buttons_length);
  EXPECT_EQ(0.0f, output.items[0].buttons[0].value);
  EXPECT_FALSE(output.items[0].buttons[0].pressed);
  ASSERT_EQ(1u, output.items[0].axes_length);
  EXPECT_EQ(0.0f, output.items[0].axes[0]);

  // Re-set the active inputs
  mock_data_fetcher_->SetTestData(active_data);

  WaitForDataAndCallbacksIssued(buffer);

  // Read updated data from shared memory
  ReadGamepadHardwareBuffer(buffer, &output);

  // Should now accurately reflect the reported data.
  ASSERT_EQ(1u, output.items[0].buttons_length);
  EXPECT_EQ(1.0f, output.items[0].buttons[0].value);
  EXPECT_TRUE(output.items[0].buttons[0].pressed);
  ASSERT_EQ(1u, output.items[0].axes_length);
  EXPECT_EQ(-1.0f, output.items[0].axes[0]);
}

TEST_F(GamepadProviderTest, HasInputChangedDetectsButtonChanges) {
  EnableRawInputChangeDetection();
  TestRawInputChangeDetection(
      "button changes",
      // Setup input change data.
      base::BindOnce([](Gamepads& data) {
        data.items[0].buttons[0].value = 1.0f;
        data.items[0].buttons[0].pressed = false;
      }),
      // Verify final state.
      base::BindOnce([](const Gamepads& output) {
        EXPECT_EQ(1.0f, output.items[0].buttons[0].value);
        EXPECT_EQ(false, output.items[0].buttons[0].pressed);
      }));
}

TEST_F(GamepadProviderTest, HasInputChangedDetectsAxisChanges) {
  EnableRawInputChangeDetection();
  TestRawInputChangeDetection("axis changes",
                              // Setup input change data.
                              base::BindOnce([](Gamepads& data) {
                                data.items[0].axes[0] = -1.0f;
                                data.items[0].axes[1] = 0.3f;
                              }),
                              // Verify final state.
                              base::BindOnce([](const Gamepads& output) {
                                EXPECT_EQ(-1.0f, output.items[0].axes[0]);
                                EXPECT_EQ(0.3f, output.items[0].axes[1]);
                              }));
}

TEST_F(GamepadProviderTest, HasInputChangedDetectsTouchChanges) {
  EnableRawInputChangeDetection();
  TestRawInputChangeDetection(
      "touch changes",
      // Setup input change data (change touch events after user gesture).
      base::BindOnce([](Gamepads& data) {
        data.items[0].touch_events[0].x = -0.2f;
        data.items[0].touch_events[0].y = 0.8f;
        data.items[0].touch_events[1].x = 1.0f;
        data.items[0].touch_events[1].y = -0.4f;
      }),
      // Verify final state.
      base::BindOnce([](const Gamepads& output) {
        EXPECT_EQ(-0.2f, output.items[0].touch_events[0].x);
        EXPECT_EQ(0.8f, output.items[0].touch_events[0].y);
        EXPECT_EQ(1.0f, output.items[0].touch_events[1].x);
        EXPECT_EQ(-0.4f, output.items[0].touch_events[1].y);
      }));
}

TEST_F(GamepadProviderTest, NoInputChangeDetectedWithUnchangedTimestamp) {
  EnableRawInputChangeDetection();
  TestRawInputChangeDetection(
      "unchanged timestamp",
      // Setup input change data (the actual change we want to test).
      base::BindOnce([](Gamepads& data) {
        data.items[0].timestamp = kUserGestureTimeStamp;
        data.items[0].buttons[0].value = 0.5f;
      }),
      // Verify final state.
      base::BindOnce([](const Gamepads& output) {
        EXPECT_EQ(0.5f, output.items[0].buttons[0].value);
      }));
}

}  // namespace

}  // namespace device