// Copyright 2019 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.

#include "chrome/updater/updater.h"

#include <stdint.h>

#include <iterator>
#include <memory>
#include <string>
#include <utility>
#include <vector>

#include "base/at_exit.h"
#include "base/bind.h"
#include "base/command_line.h"
#include "base/files/file_path.h"
#include "base/logging.h"
#include "base/memory/scoped_refptr.h"
#include "base/message_loop/message_pump_type.h"
#include "base/optional.h"
#include "base/run_loop.h"
#include "base/stl_util.h"
#include "base/task/post_task.h"
#include "base/task/single_thread_task_executor.h"
#include "base/task/thread_pool/thread_pool.h"
#include "base/task_runner.h"
#include "base/threading/platform_thread.h"
#include "base/threading/thread_restrictions.h"
#include "base/threading/thread_task_runner_handle.h"
#include "base/time/time.h"
#include "build/build_config.h"
#include "chrome/updater/configurator.h"
#include "chrome/updater/crash_client.h"
#include "chrome/updater/crash_reporter.h"
#include "chrome/updater/installer.h"
#include "chrome/updater/updater_constants.h"
#include "chrome/updater/updater_version.h"
#include "chrome/updater/util.h"
#include "components/crash/core/common/crash_key.h"
#include "components/prefs/pref_service.h"
#include "components/update_client/crx_update_item.h"
#include "components/update_client/update_client.h"

#if defined(OS_WIN)
#include "chrome/updater/win/setup/setup.h"
#include "chrome/updater/win/setup/uninstall.h"
#endif

// To install the updater, run:
// "updater.exe --install --enable-logging --v=1 --vmodule=*/chrome/updater/*"
// from the build directory. The program needs a number of dependencies which
// are available in the build out directory.
// To uninstall, run "updater.exe --uninstall" from its install directory or
// from the build out directory. Doing this will make the program delete its
// install directory using a shim cmd script.
namespace updater {

namespace {

// For now, use the Flash CRX for testing.
// CRX id is mimojjlkmoijpicakmndhoigimigcmbb.
const uint8_t mimo_hash[] = {0xc8, 0xce, 0x99, 0xba, 0xce, 0x89, 0xf8, 0x20,
                             0xac, 0xd3, 0x7e, 0x86, 0x8c, 0x86, 0x2c, 0x11,
                             0xb9, 0x40, 0xc5, 0x55, 0xaf, 0x08, 0x63, 0x70,
                             0x54, 0xf9, 0x56, 0xd3, 0xe7, 0x88, 0xba, 0x8c};

void ThreadPoolStart() {
  base::ThreadPoolInstance::CreateAndStartWithDefaultParams("Updater");
}

void ThreadPoolStop() {
  base::ThreadPoolInstance::Get()->Shutdown();
}

void QuitLoop(base::OnceClosure quit_closure) {
  std::move(quit_closure).Run();
}

class Observer : public update_client::UpdateClient::Observer {
 public:
  explicit Observer(scoped_refptr<update_client::UpdateClient> update_client)
      : update_client_(update_client) {}

  // Overrides for update_client::UpdateClient::Observer.
  void OnEvent(Events event, const std::string& id) override {
    update_client_->GetCrxUpdateState(id, &crx_update_item_);
  }

  const update_client::CrxUpdateItem& crx_update_item() const {
    return crx_update_item_;
  }

 private:
  scoped_refptr<update_client::UpdateClient> update_client_;
  update_client::CrxUpdateItem crx_update_item_;
  DISALLOW_COPY_AND_ASSIGN(Observer);
};

// The log file is created in DIR_LOCAL_APP_DATA or DIR_APP_DATA.
void InitLogging(const base::CommandLine& command_line) {
  logging::LoggingSettings settings;
  base::FilePath log_dir;
  GetProductDirectory(&log_dir);
  const auto log_file = log_dir.Append(FILE_PATH_LITERAL("updater.log"));
  settings.log_file_path = log_file.value().c_str();
  settings.logging_dest = logging::LOG_TO_ALL;
  logging::InitLogging(settings);
  logging::SetLogItems(true,    // enable_process_id
                       true,    // enable_thread_id
                       true,    // enable_timestamp
                       false);  // enable_tickcount
  VLOG(1) << "Log file " << settings.log_file_path;
}

void InitializeUpdaterMain() {
  crash_reporter::InitializeCrashKeys();

  static crash_reporter::CrashKeyString<16> crash_key_process_type(
      "process_type");
  crash_key_process_type.Set("updater");

  if (CrashClient::GetInstance()->InitializeCrashReporting())
    VLOG(1) << "Crash reporting initialized.";
  else
    VLOG(1) << "Crash reporting is not available.";

  StartCrashReporter(UPDATER_VERSION_STRING);

  ThreadPoolStart();
}

void TerminateUpdaterMain() {
  ThreadPoolStop();
}

int UpdaterInstall() {
#if defined(OS_WIN)
  return Setup();
#else
  return -1;
#endif
}

int UpdaterUninstall() {
#if defined(OS_WIN)
  return Uninstall();
#else
  return -1;
#endif
}

int UpdaterUpdateApps() {
  auto installer = base::MakeRefCounted<Installer>(
      std::vector<uint8_t>(std::cbegin(mimo_hash), std::cend(mimo_hash)));
  installer->FindInstallOfApp();
  const auto component = installer->MakeCrxComponent();

  base::SingleThreadTaskExecutor main_task_executor(base::MessagePumpType::UI);
  base::RunLoop runloop;
  DCHECK(base::ThreadTaskRunnerHandle::IsSet());

  auto config = base::MakeRefCounted<Configurator>();
  {
    base::ScopedDisallowBlocking no_blocking_allowed;

    auto update_client = update_client::UpdateClientFactory(config);

    Observer observer(update_client);
    update_client->AddObserver(&observer);

    const std::vector<std::string> ids = {installer->crx_id()};
    update_client->Update(
        ids,
        base::BindOnce(
            [](const update_client::CrxComponent& component,
               const std::vector<std::string>& ids)
                -> std::vector<base::Optional<update_client::CrxComponent>> {
              DCHECK_EQ(1u, ids.size());
              return {component};
            },
            component),
        true,
        base::BindOnce(
            [](base::OnceClosure closure, update_client::Error error) {
              base::ThreadTaskRunnerHandle::Get()->PostTask(
                  FROM_HERE, base::BindOnce(&QuitLoop, std::move(closure)));
            },
            runloop.QuitWhenIdleClosure()));

    runloop.Run();

    const auto& update_item = observer.crx_update_item();
    switch (update_item.state) {
      case update_client::ComponentState::kUpdated:
        VLOG(1) << "Update success.";
        break;
      case update_client::ComponentState::kUpToDate:
        VLOG(1) << "No updates.";
        break;
      case update_client::ComponentState::kUpdateError:
        VLOG(1) << "Updater error: " << update_item.error_code << ".";
        break;
      default:
        NOTREACHED();
        break;
    }
    update_client->RemoveObserver(&observer);
    update_client = nullptr;
  }

  {
    base::RunLoop runloop;
    config->GetPrefService()->CommitPendingWrite(base::BindOnce(
        [](base::OnceClosure quit_closure) { std::move(quit_closure).Run(); },
        runloop.QuitWhenIdleClosure()));
    runloop.Run();
  }

  return 0;
}

}  // namespace

int HandleUpdaterCommands(const base::CommandLine* command_line) {
  DCHECK(!command_line->HasSwitch(kCrashHandlerSwitch));

  if (command_line->HasSwitch(kCrashMeSwitch)) {
    int* ptr = nullptr;
    return *ptr;
  }

  if (command_line->HasSwitch(kInstallSwitch)) {
    return UpdaterInstall();
  }

  if (command_line->HasSwitch(kUninstallSwitch)) {
    return UpdaterUninstall();
  }

  if (command_line->HasSwitch(kUpdateAppsSwitch)) {
    return UpdaterUpdateApps();
  }

  VLOG(1) << "Unknown command line switch.";
  return -1;
}

int UpdaterMain(int argc, const char* const* argv) {
  base::PlatformThread::SetName("UpdaterMain");
  base::AtExitManager exit_manager;

  base::CommandLine::Init(argc, argv);
  const auto* command_line = base::CommandLine::ForCurrentProcess();
  if (command_line->HasSwitch(kTestSwitch))
    return 0;

  InitLogging(*command_line);

  if (command_line->HasSwitch(kCrashHandlerSwitch))
    return CrashReporterMain();

  InitializeUpdaterMain();
  const auto result = HandleUpdaterCommands(command_line);
  TerminateUpdaterMain();
  return result;
}

}  // namespace updater