// Copyright 2019 The Fuchsia 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 <fuchsia/devicesettings/cpp/fidl.h>
#include <fuchsia/sys/cpp/fidl.h>
#include <lib/async/default.h>
#include <lib/sys/cpp/testing/component_interceptor.h>

#include <gtest/gtest.h>
#include <src/lib/files/glob.h>

#include "lib/sys/cpp/testing/test_with_environment.h"
#include "src/lib/files/directory.h"
#include "src/lib/files/file.h"
#include "src/ui/scenic/lib/scenic/scenic.h"

constexpr char kBasemgrHubPathForTests[] = "/hub/r/env/*/c/basemgr.cmx/*/out/debug/basemgr";
constexpr char kScenicGlobPath[] = "/hub/r/env/*/c/scenic.cmx";

class BasemgrLauncherTest : public sys::testing::TestWithEnvironment {
 public:
  BasemgrLauncherTest()
      : interceptor_(sys::testing::ComponentInterceptor::CreateWithEnvironmentLoader(real_env())) {}

 protected:
  void SetUp() override {
    // Setup an enclosing environment DeviceSettings service for basemgr.
    // Add Scenic to ensure that it shuts down nicely when basemgr shuts down.
    // Add Presenter to ensure no false negatives for Scenic being launched.
    auto enclosing_env_services = interceptor_.MakeEnvironmentServices(real_env());
    enclosing_env_services->AddServiceWithLaunchInfo(
        fuchsia::sys::LaunchInfo{.url = "fuchsia-pkg://fuchsia.com/device_settings_manager#meta/"
                                        "device_settings_manager.cmx"},
        fuchsia::devicesettings::DeviceSettingsManager::Name_);

    enclosing_env_services->AddServiceWithLaunchInfo(
        fuchsia::sys::LaunchInfo{.url = "fuchsia-pkg://fuchsia.com/scenic#meta/scenic.cmx"},
        fuchsia::ui::scenic::Scenic::Name_);

    env_ = sys::testing::EnclosingEnvironment::Create("env", real_env(),
                                                      std::move(enclosing_env_services));
  }

  int64_t RunBasemgrLauncher(std::vector<std::string> args) {
    fuchsia::sys::LaunchInfo launch_info;
    launch_info.url = "fuchsia-pkg://fuchsia.com/basemgr_launcher#meta/basemgr_launcher.cmx";
    launch_info.arguments = args;

    // Launch basemgr_launcher in enclosing environment
    fuchsia::sys::ComponentControllerPtr controller;
    env_->CreateComponent(std::move(launch_info), controller.NewRequest());

    bool terminated = false;
    int64_t exit_code;
    controller.events().OnTerminated = [&](int64_t code, fuchsia::sys::TerminationReason reason) {
      terminated = true;
      exit_code = code;
    };

    RunLoopUntil([&] { return terminated; });
    return exit_code;
  }

  std::unique_ptr<sys::testing::EnclosingEnvironment> env_;
  sys::testing::ComponentInterceptor interceptor_;
};

TEST_F(BasemgrLauncherTest, BasemgrLauncherDestroysRunningBasemgr) {
  // Launch basemgr.
  EXPECT_EQ(ZX_OK, RunBasemgrLauncher({}));

  // Get the exact service path, which includes a unique id, of the basemgr instance.
  std::string service_path;
  RunLoopUntil([&] {
    files::Glob glob(kBasemgrHubPathForTests);
    if (glob.size() == 1) {
      service_path = *glob.begin();
      return true;
    }
    return false;
  });

  EXPECT_EQ(ZX_OK, RunBasemgrLauncher({}));

  // Check that the first instance of basemgr no longer exists in the hub and that it has been
  // replaced with another instance.
  RunLoopUntil([&] { return files::Glob(service_path).size() == 0; });
  RunLoopUntil([&] { return files::Glob(kBasemgrHubPathForTests).size() == 1; });
}

// Ensures basemgr isn't launched when bad arguments are provided to basemgr_launcher.
TEST_F(BasemgrLauncherTest, BadArgs) {
  // Run basemgr_launcher with invalid arguments.
  EXPECT_EQ(ZX_ERR_INVALID_ARGS, RunBasemgrLauncher({std::string("not_supported")}));
}

// When shutdown is issued but there is no running basemgr, expect an OK result.
TEST_F(BasemgrLauncherTest, NoopShutdownReturnsOk) {
  EXPECT_EQ(ZX_OK, RunBasemgrLauncher({"shutdown"}));
}

// When shutdown is issued, ensure that basemgr.cmx completely shuts down.
TEST_F(BasemgrLauncherTest, ShutdownBasemgrCommand) {
  EXPECT_EQ(ZX_OK, RunBasemgrLauncher({}));

  // Get the exact service path, which includes a unique id, of the basemgr instance.
  std::string service_path;
  RunLoopUntil([&] {
    files::Glob glob(kBasemgrHubPathForTests);
    if (glob.size() == 1) {
      service_path = *glob.begin();
      return true;
    }
    return false;
  });

  ASSERT_EQ(ZX_OK, RunBasemgrLauncher({"shutdown"}));

  // Check that the instance of basemgr no longer exists in the hub and it did not restart.
  RunLoopUntil([&] { return files::Glob(service_path).size() == 0; });
  RunLoopUntil([&] { return files::Glob(kBasemgrHubPathForTests).size() == 0; });
}