//
// Copyright (C) 2015 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

#include "tpm_manager/server/dbus_service.h"

#include <memory>
#include <string>

#include <brillo/bind_lambda.h>
#include <brillo/daemons/dbus_daemon.h>
#include <brillo/dbus/async_event_sequencer.h>
#include <dbus/bus.h>
#include <dbus/object_path.h>

#include "tpm_manager/common/tpm_manager_constants.h"
#include "tpm_manager/common/tpm_nvram_dbus_interface.h"
#include "tpm_manager/common/tpm_ownership_dbus_interface.h"

namespace tpm_manager {

using brillo::dbus_utils::DBusObject;

DBusService::DBusService(TpmNvramInterface* nvram_service,
                         TpmOwnershipInterface* ownership_service)
    : brillo::DBusServiceDaemon(tpm_manager::kTpmManagerServiceName),
      nvram_service_(nvram_service),
      ownership_service_(ownership_service) {}

DBusService::DBusService(scoped_refptr<dbus::Bus> bus,
                         TpmNvramInterface* nvram_service,
                         TpmOwnershipInterface* ownership_service)
    : brillo::DBusServiceDaemon(tpm_manager::kTpmManagerServiceName),
      dbus_object_(new DBusObject(nullptr,
                                  bus,
                                  dbus::ObjectPath(kTpmManagerServicePath))),
      nvram_service_(nvram_service),
      ownership_service_(ownership_service) {}

void DBusService::RegisterDBusObjectsAsync(
    brillo::dbus_utils::AsyncEventSequencer* sequencer) {
  if (!dbus_object_.get()) {
    // At this point bus_ should be valid.
    CHECK(bus_.get());
    dbus_object_.reset(new DBusObject(
        nullptr, bus_, dbus::ObjectPath(kTpmManagerServicePath)));
  }
  brillo::dbus_utils::DBusInterface* ownership_dbus_interface =
      dbus_object_->AddOrGetInterface(kTpmOwnershipInterface);

  ownership_dbus_interface->AddMethodHandler(
      kGetTpmStatus, base::Unretained(this),
      &DBusService::HandleOwnershipDBusMethod<
          GetTpmStatusRequest, GetTpmStatusReply,
          &TpmOwnershipInterface::GetTpmStatus>);

  ownership_dbus_interface->AddMethodHandler(
      kTakeOwnership, base::Unretained(this),
      &DBusService::HandleOwnershipDBusMethod<
          TakeOwnershipRequest, TakeOwnershipReply,
          &TpmOwnershipInterface::TakeOwnership>);

  ownership_dbus_interface->AddMethodHandler(
      kRemoveOwnerDependency, base::Unretained(this),
      &DBusService::HandleOwnershipDBusMethod<
          RemoveOwnerDependencyRequest, RemoveOwnerDependencyReply,
          &TpmOwnershipInterface::RemoveOwnerDependency>);

  brillo::dbus_utils::DBusInterface* nvram_dbus_interface =
      dbus_object_->AddOrGetInterface(kTpmNvramInterface);

  nvram_dbus_interface->AddMethodHandler(
      kDefineSpace, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<DefineSpaceRequest, DefineSpaceReply,
                                          &TpmNvramInterface::DefineSpace>);

  nvram_dbus_interface->AddMethodHandler(
      kDestroySpace, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<DestroySpaceRequest,
                                          DestroySpaceReply,
                                          &TpmNvramInterface::DestroySpace>);

  nvram_dbus_interface->AddMethodHandler(
      kWriteSpace, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<WriteSpaceRequest, WriteSpaceReply,
                                          &TpmNvramInterface::WriteSpace>);

  nvram_dbus_interface->AddMethodHandler(
      kReadSpace, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<ReadSpaceRequest, ReadSpaceReply,
                                          &TpmNvramInterface::ReadSpace>);

  nvram_dbus_interface->AddMethodHandler(
      kLockSpace, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<LockSpaceRequest, LockSpaceReply,
                                          &TpmNvramInterface::LockSpace>);

  nvram_dbus_interface->AddMethodHandler(
      kListSpaces, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<ListSpacesRequest, ListSpacesReply,
                                          &TpmNvramInterface::ListSpaces>);

  nvram_dbus_interface->AddMethodHandler(
      kGetSpaceInfo, base::Unretained(this),
      &DBusService::HandleNvramDBusMethod<GetSpaceInfoRequest,
                                          GetSpaceInfoReply,
                                          &TpmNvramInterface::GetSpaceInfo>);

  dbus_object_->RegisterAsync(
      sequencer->GetHandler("Failed to register D-Bus object.", true));
}

template <typename RequestProtobufType,
          typename ReplyProtobufType,
          DBusService::HandlerFunction<RequestProtobufType,
                                       ReplyProtobufType,
                                       TpmNvramInterface> func>
void DBusService::HandleNvramDBusMethod(
    std::unique_ptr<DBusMethodResponse<const ReplyProtobufType&>> response,
    const RequestProtobufType& request) {
  // Convert |response| to a shared_ptr so |nvram_service_| can safely copy the
  // callback.
  using SharedResponsePointer =
      std::shared_ptr<DBusMethodResponse<const ReplyProtobufType&>>;
  // A callback that sends off the reply protobuf.
  auto callback = [](const SharedResponsePointer& response,
                     const ReplyProtobufType& reply) {
    response->Return(reply);
  };
  (nvram_service_->*func)(
      request,
      base::Bind(callback, SharedResponsePointer(std::move(response))));
}

template <typename RequestProtobufType,
          typename ReplyProtobufType,
          DBusService::HandlerFunction<RequestProtobufType,
                                       ReplyProtobufType,
                                       TpmOwnershipInterface> func>
void DBusService::HandleOwnershipDBusMethod(
    std::unique_ptr<DBusMethodResponse<const ReplyProtobufType&>> response,
    const RequestProtobufType& request) {
  // Convert |response| to a shared_ptr so |ownership_service_| can safely
  // copy the callback.
  using SharedResponsePointer =
      std::shared_ptr<DBusMethodResponse<const ReplyProtobufType&>>;
  // A callback that sends off the reply protobuf.
  auto callback = [](const SharedResponsePointer& response,
                     const ReplyProtobufType& reply) {
    response->Return(reply);
  };
  (ownership_service_->*func)(
      request,
      base::Bind(callback, SharedResponsePointer(std::move(response))));
}

}  // namespace tpm_manager