// Copyright 2023 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_SIGNIN_BOUND_SESSION_CREDENTIALS_BOUND_SESSION_REGISTRATION_FETCHER_IMPL_H_
#define CHROME_BROWSER_SIGNIN_BOUND_SESSION_CREDENTIALS_BOUND_SESSION_REGISTRATION_FETCHER_IMPL_H_

#include <memory>
#include <optional>
#include <string>

#include "base/functional/callback.h"
#include "base/memory/raw_ref.h"
#include "base/timer/elapsed_timer.h"
#include "base/types/expected.h"
#include "chrome/browser/signin/bound_session_credentials/bound_session_cookie_refresh_service.h"
#include "chrome/browser/signin/bound_session_credentials/bound_session_registration_fetcher.h"
#include "chrome/browser/signin/bound_session_credentials/bound_session_registration_fetcher_param.h"
#include "components/signin/public/base/binding_key_registration_token_helper.h"
#include "components/unexportable_keys/service_error.h"
#include "components/unexportable_keys/unexportable_key_id.h"
#include "services/network/public/cpp/simple_url_loader.h"
#include "url/gurl.h"

namespace network {
class SimpleURLLoader;
class SharedURLLoaderFactory;
}  // namespace network

namespace unexportable_keys {
class UnexportableKeyService;
}

class BoundSessionRegistrationFetcherImpl
    : public BoundSessionRegistrationFetcher {
 public:
  // These values are persisted to logs. Entries should not be renumbered and
  // numeric values should never be reused.
  // Public for testing.
  enum class RegistrationError {
    kNone = 0,
    kGenerateRegistrationTokenFailed = 1,
    kNetworkError = 2,
    kServerError = 3,
    kParseJsonFailed = 4,
    kRequiredFieldMissing = 5,
    kInvalidSessionParams = 6,
    kRequiredCredentialFieldMissing = 7,
    kUnexpectedParserError = 8,
    kMaxValue = kUnexpectedParserError
  };

  BoundSessionRegistrationFetcherImpl(
      BoundSessionRegistrationFetcherParam registration_params,
      scoped_refptr<network::SharedURLLoaderFactory> loader_factory,
      unexportable_keys::UnexportableKeyService& key_service,
      bool is_off_the_record_profile);

  BoundSessionRegistrationFetcherImpl(
      BoundSessionRegistrationFetcherImpl&& other) = delete;
  BoundSessionRegistrationFetcherImpl& operator=(
      BoundSessionRegistrationFetcherImpl&& other) noexcept = delete;

  BoundSessionRegistrationFetcherImpl(
      const BoundSessionRegistrationFetcherImpl&) = delete;
  BoundSessionRegistrationFetcherImpl& operator=(
      const BoundSessionRegistrationFetcherImpl&) = delete;
  ~BoundSessionRegistrationFetcherImpl() override;

  // BoundSessionRegistrationFetcher:
  void Start(RegistrationCompleteCallback callback) override;

 private:
  template <class Result>
  using RegistrationErrorOr = base::expected<Result, RegistrationError>;

  void OnURLLoaderComplete(std::optional<std::string> response_body);
  void OnRegistrationTokenCreated(
      base::ElapsedTimer generate_registration_token_timer,
      std::optional<signin::BindingKeyRegistrationTokenHelper::Result> result);

  void StartFetchingRegistration(const std::string& registration_token);

  void RunCallbackAndRecordMetrics(
      RegistrationErrorOr<bound_session_credentials::BoundSessionParams>
          params_or_error);

  RegistrationErrorOr<bound_session_credentials::BoundSessionParams>
  ParseJsonResponse(const std::string& response_body);

  BoundSessionRegistrationFetcherParam registration_params_;
  const raw_ref<unexportable_keys::UnexportableKeyService> key_service_;
  const bool is_off_the_record_profile_;
  std::string wrapped_key_str_;

  // Non-null after a fetch has started.
  std::unique_ptr<network::SimpleURLLoader> url_loader_;
  std::optional<base::ElapsedTimer> registration_duration_;
  const scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory_;
  std::unique_ptr<signin::BindingKeyRegistrationTokenHelper>
      registration_token_helper_;

  RegistrationCompleteCallback callback_;
};
#endif  // CHROME_BROWSER_SIGNIN_BOUND_SESSION_CREDENTIALS_BOUND_SESSION_REGISTRATION_FETCHER_IMPL_H_