// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "remoting/base/cloud_service_client.h"

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

#include "base/functional/bind.h"
#include "base/memory/ptr_util.h"
#include "base/strings/string_split.h"
#include "base/strings/stringize_macros.h"
#include "google_apis/google_api_keys.h"
#include "net/http/http_request_headers.h"
#include "remoting/base/protobuf_http_request.h"
#include "remoting/base/protobuf_http_request_config.h"
#include "remoting/base/service_urls.h"
#include "remoting/base/version.h"
#include "remoting/proto/google/internal/remoting/cloud/v1alpha/empty.pb.h"
#include "remoting/proto/google/internal/remoting/cloud/v1alpha/network_traversal_service.pb.h"
#include "remoting/proto/google/internal/remoting/cloud/v1alpha/remote_access_host.pb.h"
#include "remoting/proto/google/internal/remoting/cloud/v1alpha/remote_access_service.pb.h"
#include "remoting/proto/google/internal/remoting/cloud/v1alpha/session_authz_service.pb.h"
#include "remoting/proto/google/remoting/cloud/v1/provisioning_service.pb.h"
#include "services/network/public/cpp/shared_url_loader_factory.h"

namespace {
constexpr net::NetworkTrafficAnnotationTag kGenerateHostTokenTrafficAnnotation =
    net::DefineNetworkTrafficAnnotation("remoting_cloud_generate_host_token",
                                        R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Generates a host token which is used to authorize a Chrome Remote "
            "Desktop connection between a user and a 'Cloud host' running on "
            "GCE (this machine)."
          trigger:
            "User connects to a remote access host instance running on GCE "
            "which has been configured as a 'Cloud' host."
          user_data {
            type: OTHER
          }
          data:
            "An access token for the device robot account associated with this "
            "machine."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-09-23"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the Chrome Remote Desktop host is not registered as a Cloud "
            "host running on GCE."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag
    kProvisionGceInstanceTrafficAnnotation =
        net::DefineNetworkTrafficAnnotation(
            "remoting_cloud_provision_gce_instance",
            R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Registers a new Chrome Remote Desktop host for a GCE instance."
          trigger:
            "User runs the remoting_start_host command by typing it on the "
            "terminal. Third party administrators might implement scripts to "
            "run this automatically, but the Chrome Remote Desktop product "
            "does not come with such scripts."
          user_data {
            type: EMAIL
            type: OTHER
          }
          data:
            "The email address of the account to configure CRD for and the "
            "display name of the new remote access host instance which will be "
            "shown in the Chrome Remote Desktop client website."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-03-29"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the start-host utility is not run with the cloud-user flag."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag kReauthorizeHostTrafficAnnotation =
    net::DefineNetworkTrafficAnnotation("remoting_cloud_reauthorize_host",
                                        R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Reauthorizes the Chrome Remote Desktop connection between a user "
            "and a 'Cloud host' running on GCE (this machine)."
          trigger:
            "User connects to a remote access host instance running on GCE "
            "which has been configured as a 'Cloud' host."
          user_data {
            type: OTHER
          }
          data:
            "An access token for the device robot account associated with this "
            "machine and an opaque session token generated by the backend "
            "service."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-09-23"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the Chrome Remote Desktop host is not registered as a Cloud "
            "host running on GCE."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag kSendHeartbeatTrafficAnnotation =
    net::DefineNetworkTrafficAnnotation("remoting_cloud_send_heartbeat",
                                        R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Updates the last seen time in the Chrome Remote Desktop Directory "
            "service for a given remote access host instance."
          trigger:
            "Configuring a CRD remote access host on a GCE Instance."
          user_data {
            type: OTHER
          }
          data:
            "An internal UUID to identify the remote access host instance."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-09-18"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the CRD host is not configured and run as a Cloud host."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag
    kUpdateRemoteAccessHostTrafficAnnotation =
        net::DefineNetworkTrafficAnnotation(
            "remoting_cloud_update_remote_access_host",
            R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Updates the Chrome Remote Desktop Directory service with "
            "environment details and signaling information for a given remote "
            "access host instance."
          trigger:
            "Configuring a CRD remote access host on a GCE Instance."
          user_data {
            type: OTHER
          }
          data:
            "Includes an internal UUID to identify the remote access host "
            "instance, the name and version of the operating system, the "
            "version of the CRD package installed, and a set of signaling ids "
            "which the CRD client can use to send the host messages."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-09-18"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the CRD host is not configured and run as a Cloud host."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag
    kVerifySessionTokenTrafficAnnotation = net::DefineNetworkTrafficAnnotation(
        "remoting_cloud_verify_session_token",
        R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Verifies a session token returned by the client device and "
            "decodes the shared secret from the session token, to be used to "
            "authorize a Chrome Remote Desktop connection between a user and a "
            "Cloud host running on GCE (this device)."
          trigger:
            "User connects to a remote access host instance running on GCE "
            "which has been configured as a 'Cloud' host."
          user_data {
            type: OTHER
          }
          data:
            "An access token for the device robot account associated with this "
            "machine and an opaque session token generated by the backend "
            "service."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-09-23"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the Chrome Remote Desktop host is not registered as a Cloud "
            "host running on GCE."
          policy_exception_justification:
            "Not implemented."
        })");

constexpr net::NetworkTrafficAnnotationTag kGenerateIceConfigTrafficAnnotation =
    net::DefineNetworkTrafficAnnotation("remoting_cloud_generate_ice_config",
                                        R"(
        semantics {
          sender: "Chrome Remote Desktop"
          description:
            "Request used by Chrome Remote Desktop to fetch an ICE "
            "(Interactive Connectivity Establishment) configuration which "
            "contains a list of STUN (Session Traversal Utilities for NAT) & "
            "TURN (Traversal Using Relay NAT) servers and TURN credentials. "
            "Please see https://tools.ietf.org/html/rfc5245 for more details."
          trigger:
            "When a user connects to a remote access host instance running on "
            "GCE which has been configured as a 'Cloud' host."
          user_data {
            type: OTHER
          }
          data:
            "An access token for the device robot account associated with this "
            "machine."
          destination: GOOGLE_OWNED_SERVICE
          internal {
            contacts { owners: "//remoting/OWNERS" }
          }
          last_reviewed: "2024-10-08"
        }
        policy {
          cookies_allowed: NO
          setting:
            "This request cannot be stopped in settings, but will not be sent "
            "if the Chrome Remote Desktop host is not registered as a Cloud "
            "host running on GCE."
          policy_exception_justification:
            "Not implemented."
        })");

// Remoting Cloud API using statements.
using ProvisionGceInstanceRequest =
    google::remoting::cloud::v1::ProvisionGceInstanceRequest;

// Remoting Cloud Private API using statements.
using Empty = google::internal::remoting::cloud::v1alpha::Empty;
using GenerateHostTokenRequest =
    google::internal::remoting::cloud::v1alpha::GenerateHostTokenRequest;
using GenerateIceConfigRequest =
    google::internal::remoting::cloud::v1alpha::GenerateIceConfigRequest;
using ReauthorizeHostRequest =
    google::internal::remoting::cloud::v1alpha::ReauthorizeHostRequest;
using RemoteAccessHost =
    google::internal::remoting::cloud::v1alpha::RemoteAccessHost;
using SendHeartbeatRequest =
    google::internal::remoting::cloud::v1alpha::SendHeartbeatRequest;
using VerifySessionTokenRequest =
    google::internal::remoting::cloud::v1alpha::VerifySessionTokenRequest;

constexpr char kFtlResourceSeparator[] = "/chromoting_ftl_";

}  // namespace

namespace remoting {

CloudServiceClient::CloudServiceClient(
    const std::string& api_key,
    OAuthTokenGetter* oauth_token_getter,
    const std::string& base_service_url,
    scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory)
    : api_key_(api_key),
      http_client_(base_service_url, oauth_token_getter, url_loader_factory) {}

CloudServiceClient::~CloudServiceClient() = default;

void CloudServiceClient::ProvisionGceInstance(
    const std::string& owner_email,
    const std::string& display_name,
    const std::string& public_key,
    const std::optional<std::string>& existing_directory_id,
    const std::optional<std::string>& instance_identity_token,
    ProvisionGceInstanceCallback callback) {
  constexpr char path[] = "/v1/provisioning:provisionGceInstance";

  auto request = std::make_unique<ProvisionGceInstanceRequest>();
  request->set_owner_email(owner_email);
  request->set_display_name(display_name);
  request->set_public_key(public_key);
  request->set_version(STRINGIZE(VERSION));
  if (existing_directory_id.has_value() && !existing_directory_id->empty()) {
    request->set_existing_directory_id(*existing_directory_id);
  }
  if (instance_identity_token.has_value() &&
      !instance_identity_token->empty()) {
    request->set_instance_identity_token(*instance_identity_token);
  }

  ExecuteRequest(kProvisionGceInstanceTrafficAnnotation, path, api_key_,
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback));
}

void CloudServiceClient::SendHeartbeat(const std::string& directory_id,
                                       std::string_view instance_identity_token,
                                       SendHeartbeatCallback callback) {
  constexpr char path[] = "/v1alpha/access:sendHeartbeat";

  auto request = std::make_unique<SendHeartbeatRequest>();
  request->set_directory_id(directory_id);
  request->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kSendHeartbeatTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback));
}

void CloudServiceClient::UpdateRemoteAccessHost(
    const std::string& directory_id,
    std::optional<std::string> host_version,
    std::optional<std::string> signaling_id,
    std::optional<std::string> offline_reason,
    std::optional<std::string> os_name,
    std::optional<std::string> os_version,
    std::string_view instance_identity_token,
    UpdateRemoteAccessHostCallback callback) {
  constexpr char path[] = "/v1alpha/access:updateRemoteAccessHost";

  auto host = std::make_unique<RemoteAccessHost>();

  host->set_directory_id(directory_id);
  if (host_version.has_value()) {
    host->set_version(*host_version);
  }
  if (signaling_id.has_value()) {
    auto parts = base::SplitStringUsingSubstr(
        *signaling_id, kFtlResourceSeparator, base::TRIM_WHITESPACE,
        base::SPLIT_WANT_ALL);
    if (parts.size() == 2) {
      host->mutable_tachyon_account_info()->set_account_id(std::move(parts[0]));
      host->mutable_tachyon_account_info()->set_registration_id(
          std::move(parts[1]));
    } else {
      LOG(WARNING) << "Invalid signaling_id provided: " << *signaling_id;
    }
  }
  if (offline_reason.has_value()) {
    host->set_offline_reason(*offline_reason);
  }
  if (os_name.has_value() && os_version.has_value()) {
    host->mutable_operating_system_info()->set_name(*os_name);
    host->mutable_operating_system_info()->set_version(*os_version);
  }
  host->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kUpdateRemoteAccessHostTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPatchMethod, std::move(host),
                 std::move(callback));
}

void CloudServiceClient::GenerateHostToken(
    std::string_view instance_identity_token,
    GenerateHostTokenCallback callback) {
  constexpr char path[] = "/v1alpha/sessionAuthz:generateHostToken";

  auto request = std::make_unique<GenerateHostTokenRequest>();
  request->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kGenerateHostTokenTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback));
}

void CloudServiceClient::GenerateIceConfig(
    std::string_view instance_identity_token,
    GenerateIceConfigCallback callback) {
  constexpr char path[] = "/v1alpha/networkTraversal:generateIceConfig";

  auto request = std::make_unique<GenerateIceConfigRequest>();
  request->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kGenerateIceConfigTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback));
}

void CloudServiceClient::VerifySessionToken(
    const std::string& session_token,
    std::string_view instance_identity_token,
    VerifySessionTokenCallback callback) {
  constexpr char path[] = "/v1alpha/sessionAuthz:verifySessionToken";

  auto request = std::make_unique<VerifySessionTokenRequest>();
  request->set_session_token(session_token);
  request->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kVerifySessionTokenTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback));
}

void CloudServiceClient::ReauthorizeHost(
    const std::string& session_reauth_token,
    const std::string& session_id,
    std::string_view instance_identity_token,
    scoped_refptr<const ProtobufHttpRequestConfig::RetryPolicy> retry_policy,
    ReauthorizeHostCallback callback) {
  constexpr char path[] = "/v1alpha/sessionAuthz:reauthorizeHost";

  auto request = std::make_unique<ReauthorizeHostRequest>();
  request->set_session_reauth_token(session_reauth_token);
  request->set_session_id(session_id);
  request->set_instance_identity_token(instance_identity_token);

  ExecuteRequest(kReauthorizeHostTrafficAnnotation, path, /*api_key=*/"",
                 net::HttpRequestHeaders::kPostMethod, std::move(request),
                 std::move(callback), std::move(retry_policy));
}

void CloudServiceClient::CancelPendingRequests() {
  http_client_.CancelPendingRequests();
}

template <typename CallbackType>
void CloudServiceClient::ExecuteRequest(
    const net::NetworkTrafficAnnotationTag& traffic_annotation,
    const std::string& path,
    const std::string& api_key,
    const std::string& method,
    std::unique_ptr<google::protobuf::MessageLite> request_message,
    CallbackType callback,
    scoped_refptr<const ProtobufHttpRequestConfig::RetryPolicy> retry_policy) {
  auto request_config =
      std::make_unique<ProtobufHttpRequestConfig>(traffic_annotation);
  request_config->path = path;
  if (api_key.empty()) {
    request_config->authenticated = true;
  } else {
    request_config->api_key = api_key;
    request_config->authenticated = false;
  }
  request_config->method = method;
  request_config->retry_policy = std::move(retry_policy);
  request_config->request_message = std::move(request_message);
  auto request =
      std::make_unique<ProtobufHttpRequest>(std::move(request_config));
  request->SetResponseCallback(std::move(callback));
  http_client_.ExecuteRequest(std::move(request));
}

// static
std::unique_ptr<CloudServiceClient>
CloudServiceClient::CreateForChromotingRobotAccount(
    OAuthTokenGetter* oauth_token_getter,
    scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory) {
  return base::WrapUnique(new CloudServiceClient(
      /*api_key=*/std::string(), oauth_token_getter,
      ServiceUrls::GetInstance()->remoting_cloud_private_endpoint(),
      url_loader_factory));
}

// static
std::unique_ptr<CloudServiceClient> CloudServiceClient::CreateForGcpProject(
    const std::string& api_key,
    scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory) {
  return base::WrapUnique(new CloudServiceClient(
      api_key,
      /*oauth_token_getter=*/nullptr,
      ServiceUrls::GetInstance()->remoting_cloud_public_endpoint(),
      url_loader_factory));
}

// static
std::unique_ptr<CloudServiceClient>
CloudServiceClient::CreateForGceDefaultServiceAccount(
    OAuthTokenGetter* oauth_token_getter,
    scoped_refptr<network::SharedURLLoaderFactory> url_loader_factory) {
  return base::WrapUnique(new CloudServiceClient(
      /*api_key=*/std::string(), oauth_token_getter,
      ServiceUrls::GetInstance()->remoting_cloud_public_endpoint(),
      url_loader_factory));
}

}  // namespace remoting