// Copyright 2020 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "gtest/gtest.h"

#include <lib/async-loop/default.h>
#include <lib/sys/cpp/component_context.h>
#include <lib/ui/scenic/cpp/view_token_pair.h>

#include <fuchsia/sys/cpp/fidl.h>
#include <fuchsia/ui/policy/cpp/fidl.h>

#include "flutter/shell/platform/fuchsia/flutter/logging.h"
#include "flutter/shell/platform/fuchsia/flutter/runner.h"
#include "flutter/shell/platform/fuchsia/flutter/session_connection.h"

using namespace flutter_runner;

namespace flutter_runner_test {

class SessionConnectionTest : public ::testing::Test {
 public:
  void SetUp() override {
    context_ = sys::ComponentContext::Create();
    scenic_ = context_->svc()->Connect<fuchsia::ui::scenic::Scenic>();
    presenter_ = context_->svc()->Connect<fuchsia::ui::policy::Presenter>();

    FML_CHECK(ZX_OK ==
              loop_.StartThread("SessionConnectionTestThread", &fidl_thread_));

    auto session_listener_request = session_listener_.NewRequest();
    auto [view_token, view_holder_token] = scenic::ViewTokenPair::New();
    view_token_ = std::move(view_token);

    scenic_->CreateSession(session_.NewRequest(), session_listener_.Bind());
    presenter_->PresentView(std::move(view_holder_token), nullptr);

    FML_CHECK(zx::event::create(0, &vsync_event_) == ZX_OK);
  }
  // Warning: Initialization order matters here. |loop_| must be initialized
  // before |SetUp()| so that we have a dispatcher already initialized.
  async::Loop loop_ = async::Loop(&kAsyncLoopConfigAttachToCurrentThread);

  std::unique_ptr<sys::ComponentContext> context_;
  fuchsia::ui::scenic::ScenicPtr scenic_;
  fuchsia::ui::policy::PresenterPtr presenter_;

  fidl::InterfaceHandle<fuchsia::ui::scenic::Session> session_;
  fidl::InterfaceHandle<fuchsia::ui::scenic::SessionListener> session_listener_;
  fuchsia::ui::views::ViewToken view_token_;
  zx::event vsync_event_;
  thrd_t fidl_thread_;
};

TEST_F(SessionConnectionTest, SimplePresentTest) {
  fml::closure on_session_error_callback = []() { FML_CHECK(false); };

  uint64_t num_presents_handled = 0;
  on_frame_presented_event on_frame_presented_callback =
      [&num_presents_handled](
          fuchsia::scenic::scheduling::FramePresentedInfo info) {
        num_presents_handled += info.presentation_infos.size();
      };

  flutter_runner::SessionConnection session_connection(
      "debug label", std::move(view_token_), scenic::ViewRefPair::New(),
      std::move(session_), on_session_error_callback,
      on_frame_presented_callback, vsync_event_.get());

  for (int i = 0; i < 200; ++i) {
    std::this_thread::sleep_for(std::chrono::milliseconds(10));
    session_connection.Present(nullptr);
  }

  EXPECT_GT(num_presents_handled, 0u);
}

TEST_F(SessionConnectionTest, BatchedPresentTest) {
  fml::closure on_session_error_callback = []() { FML_CHECK(false); };

  uint64_t num_presents_handled = 0;
  on_frame_presented_event on_frame_presented_callback =
      [&num_presents_handled](
          fuchsia::scenic::scheduling::FramePresentedInfo info) {
        num_presents_handled += info.presentation_infos.size();
      };

  flutter_runner::SessionConnection session_connection(
      "debug label", std::move(view_token_), scenic::ViewRefPair::New(),
      std::move(session_), on_session_error_callback,
      on_frame_presented_callback, vsync_event_.get());

  for (int i = 0; i < 200; ++i) {
    if (i % 10 == 0) {
      std::this_thread::sleep_for(std::chrono::milliseconds(20));
    }
    session_connection.Present(nullptr);
  }

  EXPECT_GT(num_presents_handled, 0u);
}

}  // namespace flutter_runner_test