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

#ifndef CHROME_BROWSER_ASH_LOGIN_SCREENS_LOCALE_SWITCH_SCREEN_H_
#define CHROME_BROWSER_ASH_LOGIN_SCREENS_LOCALE_SWITCH_SCREEN_H_

#include <optional>
#include <string>

#include "base/memory/raw_ptr.h"
#include "base/memory/raw_ref.h"
#include "base/memory/weak_ptr.h"
#include "base/scoped_observation.h"
#include "base/timer/timer.h"
#include "chrome/browser/ash/base/locale_util.h"
#include "chrome/browser/ash/login/screens/base_screen.h"
#include "components/signin/public/identity_manager/access_token_info.h"
#include "components/signin/public/identity_manager/account_info.h"
#include "components/signin/public/identity_manager/identity_manager.h"
#include "google_apis/gaia/gaia_id.h"
#include "google_apis/gaia/google_service_auth_error.h"
#include "google_apis/gaia/oauth2_api_call_flow.h"

class PrefService;
class ApplicationLocaleStorage;

namespace signin {
class PrimaryAccountAccessTokenFetcher;
}  // namespace signin

namespace ash {

class LocaleSwitchView;
class ScopedSessionRefresher;

// This screen waits for account information (locale and account capabilities)
// to be fetched and handles OOBE locale switch for the post-login screens.
class LocaleSwitchScreen : public BaseScreen,
                           public signin::IdentityManager::Observer {
 public:
  enum class Result {
    kLocaleFetchFailed,
    kLocaleFetchTimeout,
    kNoSwitchNeeded,
    kSwitchSucceded,
    kSwitchFailed,
    kSwitchDelegated,
    kNotApplicable
  };

  static std::string GetResultString(Result result);

  using ScreenExitCallback = base::RepeatingCallback<void(Result result)>;
  // `local_state` must be non-null and must outlive `this`.
  // `application_locale_storage` must be non-null and must be the one
  // associated with browser process.
  LocaleSwitchScreen(PrefService* local_state,
                     ApplicationLocaleStorage* application_locale_storage,
                     base::WeakPtr<LocaleSwitchView> view,
                     const ScreenExitCallback& exit_callback);
  ~LocaleSwitchScreen() override;

  // signin::IdentityManager::Observer:
  void OnErrorStateOfRefreshTokenUpdatedForAccount(
      const CoreAccountInfo& account_info,
      const GoogleServiceAuthError& error,
      signin_metrics::SourceForRefreshTokenOperation token_operation_source)
      override;
  void OnExtendedAccountInfoUpdated(const AccountInfo& info) override;
  void OnRefreshTokensLoaded() override;

  const ScreenExitCallback& get_exit_callback_for_testing() {
    return exit_callback_;
  }

  void set_exit_callback_for_testing(const ScreenExitCallback& callback) {
    exit_callback_ = callback;
  }

 private:
  // BaseScreen:
  void ShowImpl() override;
  void HideImpl() override;
  bool MaybeSkip(WizardContext& context) override;

  void SwitchLocale();
  void OnLanguageChangedCallback(
      const locale_util::LanguageSwitchResult& result);
  void OnLanguageChangedNotificationCallback(
      const locale_util::LanguageSwitchResult& result);

  void OnLocaleFetched(std::string locale);
  void OnRequestFailure();
  void AbandonPeopleAPICall();
  void OnTimeout();

  void FetchPreferredUserLocaleAndSwitchAsync();
  void OnAccessTokenRequestCompleted(GoogleServiceAuthError error,
                                     signin::AccessTokenInfo access_token_info);

  const raw_ref<PrefService> local_state_;
  const raw_ref<ApplicationLocaleStorage> application_locale_storage_;

  std::string locale_;
  base::WeakPtr<LocaleSwitchView> view_ = nullptr;
  std::unique_ptr<signin::PrimaryAccountAccessTokenFetcher>
      access_token_fetcher_;
  std::unique_ptr<OAuth2ApiCallFlow> get_locale_people_api_call_;

  GaiaId gaia_id_;
  ScreenExitCallback exit_callback_;
  raw_ptr<signin::IdentityManager> identity_manager_ = nullptr;
  base::ScopedObservation<signin::IdentityManager,
                          signin::IdentityManager::Observer>
      identity_manager_observer_{this};

  // Keeps cryptohome authsession alive.
  std::unique_ptr<ScopedSessionRefresher> session_refresher_;

  base::OneShotTimer timeout_waiter_;

  bool refresh_token_loaded_ = false;
  bool account_capabilities_loaded_ = false;

  base::WeakPtrFactory<LocaleSwitchScreen> weak_factory_{this};
};

}  // namespace ash

#endif  // CHROME_BROWSER_ASH_LOGIN_SCREENS_LOCALE_SWITCH_SCREEN_H_