action_impl.cpp

#include "action_impl.h"
#include "mavsdk_impl.h"
#include "mavsdk_math.h"
#include "flight_mode.h"
#include "px4_custom_mode.h"
#include <cmath>
#include <future>

namespace mavsdk {

ActionImpl::ActionImpl(System& system) : PluginImplBase(system)
{
    _system_impl->register_plugin(this);
}

ActionImpl::ActionImpl(std::shared_ptr<System> system) : PluginImplBase(std::move(system))
{
    _system_impl->register_plugin(this);
}

ActionImpl::~ActionImpl()
{
    _system_impl->unregister_plugin(this);
}

void ActionImpl::init()
{
    // We need the system state.
    _system_impl->register_mavlink_message_handler(
        MAVLINK_MSG_ID_EXTENDED_SYS_STATE,
        [this](const mavlink_message_t& message) { process_extended_sys_state(message); },
        this);
}

void ActionImpl::deinit()
{
    _system_impl->unregister_all_mavlink_message_handlers(this);
}

void ActionImpl::enable()
{
    // And we need to make sure the system state is actually sent.
    // We use the async call here because we should not block in the init call because
    // we won't receive an answer anyway in init because the receive loop is not
    // called while we are being created here.
    _system_impl->set_msg_rate_async(
        MAVLINK_MSG_ID_EXTENDED_SYS_STATE,
        1.0,
        nullptr,
        MavlinkCommandSender::DEFAULT_COMPONENT_ID_AUTOPILOT);
}

void ActionImpl::disable() {}

Action::Result ActionImpl::arm() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    arm_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::arm_force() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    arm_force_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::disarm() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    disarm_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::terminate() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    terminate_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::kill() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    kill_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::reboot() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    reboot_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::shutdown() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    shutdown_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::takeoff() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    takeoff_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::land() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    land_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::return_to_launch() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    return_to_launch_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::goto_location(
    const double latitude_deg,
    const double longitude_deg,
    const float altitude_amsl_m,
    const float yaw_deg)
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    goto_location_async(
        latitude_deg, longitude_deg, altitude_amsl_m, yaw_deg, [&prom](Action::Result result) {
            prom.set_value(result);
        });

    return fut.get();
}

Action::Result ActionImpl::do_orbit(
    const float radius_m,
    const float velocity_ms,
    const Action::OrbitYawBehavior yaw_behavior,
    const double latitude_deg,
    const double longitude_deg,
    const double absolute_altitude_m)
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    do_orbit_async(
        radius_m,
        velocity_ms,
        yaw_behavior,
        latitude_deg,
        longitude_deg,
        absolute_altitude_m,
        [&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::hold() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    hold_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::set_actuator(const int index, const float value)
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    set_actuator_async(index, value, [&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::transition_to_fixedwing() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    transition_to_fixedwing_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::transition_to_multicopter() const
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    transition_to_multicopter_async([&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

void ActionImpl::arm_async(const Action::ResultCallback& callback) const
{
    auto send_arm_command = [this, callback]() {
        MavlinkCommandSender::CommandLong command{};

        command.command = MAV_CMD_COMPONENT_ARM_DISARM;
        command.params.maybe_param1 = 1.0f; // arm
        command.target_component_id = _system_impl->get_autopilot_id();

        _system_impl->send_command_async(
            command, [this, callback](MavlinkCommandSender::Result result, float) {
                command_result_callback(result, callback);
            });
    };

    if (need_hold_before_arm()) {
        _system_impl->set_flight_mode_async(
            FlightMode::Hold,
            [callback, send_arm_command](MavlinkCommandSender::Result result, float) {
                Action::Result action_result = action_result_from_command_result(result);
                if (action_result != Action::Result::Success) {
                    if (callback) {
                        callback(action_result);
                    }
                }
                send_arm_command();
            });
        return;
    } else {
        send_arm_command();
    }
}

bool ActionImpl::need_hold_before_arm() const
{
    if (_system_impl->autopilot() == Autopilot::Px4) {
        return need_hold_before_arm_px4();
    } else {
        return need_hold_before_arm_apm();
    }
}

bool ActionImpl::need_hold_before_arm_px4() const
{
    if (_system_impl->get_flight_mode() == FlightMode::Mission ||
        _system_impl->get_flight_mode() == FlightMode::ReturnToLaunch) {
        return true;
    } else {
        return false;
    }
}

bool ActionImpl::need_hold_before_arm_apm() const
{
    if (_system_impl->get_flight_mode() == FlightMode::Mission ||
        _system_impl->get_flight_mode() == FlightMode::ReturnToLaunch ||
        _system_impl->get_flight_mode() == FlightMode::Land) {
        return true;
    } else {
        return false;
    }
}

void ActionImpl::arm_force_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_COMPONENT_ARM_DISARM;
    command.params.maybe_param1 = 0.0f; // arm
    command.params.maybe_param2 = 21196.f; // magic number to force
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::disarm_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_COMPONENT_ARM_DISARM;
    command.params.maybe_param1 = 0.0f; // disarm
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::terminate_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_DO_FLIGHTTERMINATION;
    command.params.maybe_param1 = 1.0f;
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::kill_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_COMPONENT_ARM_DISARM;
    command.params.maybe_param1 = 0.0f; // kill
    command.params.maybe_param2 = 21196.f; // magic number to enforce in-air
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::reboot_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_PREFLIGHT_REBOOT_SHUTDOWN;
    command.params.maybe_param1 = 1.0f; // reboot autopilot
    command.params.maybe_param2 = 1.0f; // reboot onboard computer
    command.params.maybe_param3 = 1.0f; // reboot camera
    command.params.maybe_param4 = 1.0f; // reboot gimbal
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::shutdown_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_PREFLIGHT_REBOOT_SHUTDOWN;
    command.params.maybe_param1 = 2.0f; // shutdown autopilot
    command.params.maybe_param2 = 2.0f; // shutdown onboard computer
    command.params.maybe_param3 = 2.0f; // shutdown camera
    command.params.maybe_param4 = 2.0f; // shutdown gimbal
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::takeoff_async(const Action::ResultCallback& callback) const
{
    if (_system_impl->autopilot() == Autopilot::Px4) {
        takeoff_async_px4(callback);
    } else {
        takeoff_async_apm(callback);
    }
}

void ActionImpl::takeoff_async_px4(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_NAV_TAKEOFF;
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::takeoff_async_apm(const Action::ResultCallback& callback) const
{
    auto send_takeoff_command = [this, callback]() {
        MavlinkCommandSender::CommandLong command{};

        command.command = MAV_CMD_NAV_TAKEOFF;
        command.target_component_id = _system_impl->get_autopilot_id();
        command.params.maybe_param7 = get_takeoff_altitude().second;

        _system_impl->send_command_async(
            command, [this, callback](MavlinkCommandSender::Result result, float) {
                command_result_callback(result, callback);
            });
    };
    if (_system_impl->get_flight_mode() != FlightMode::Offboard) {
        _system_impl->set_flight_mode_async(
            FlightMode::Offboard,
            [callback, send_takeoff_command](MavlinkCommandSender::Result result, float) {
                Action::Result action_result = action_result_from_command_result(result);
                if (action_result != Action::Result::Success) {
                    if (callback) {
                        callback(action_result);
                    }
                } else {
                    send_takeoff_command();
                }
            });
    } else {
        send_takeoff_command();
    }
}

void ActionImpl::land_async(const Action::ResultCallback& callback) const
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_NAV_LAND;
    command.params.maybe_param4 = NAN; // Don't change yaw.
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::return_to_launch_async(const Action::ResultCallback& callback) const
{
    _system_impl->set_flight_mode_async(
        FlightMode::ReturnToLaunch, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::goto_location_async(
    const double latitude_deg,
    const double longitude_deg,
    const float altitude_amsl_m,
    const float yaw_deg,
    const Action::ResultCallback& callback)
{
    auto send_do_reposition =
        [this, callback, yaw_deg, latitude_deg, longitude_deg, altitude_amsl_m]() {
            MavlinkCommandSender::CommandInt command{};

            command.command = MAV_CMD_DO_REPOSITION;
            command.target_component_id = _system_impl->get_autopilot_id();
            command.frame = MAV_FRAME_GLOBAL_INT;
            command.params.maybe_param4 = static_cast<float>(to_rad_from_deg(yaw_deg));
            command.params.x = int32_t(std::round(latitude_deg * 1e7));
            command.params.y = int32_t(std::round(longitude_deg * 1e7));
            command.params.maybe_z = altitude_amsl_m;
            command.params.maybe_param2 = static_cast<float>(MAV_DO_REPOSITION_FLAGS_CHANGE_MODE);

            _system_impl->send_command_async(
                command, [this, callback](MavlinkCommandSender::Result result, float) {
                    command_result_callback(result, callback);
                });
        };
    FlightMode goto_flight_mode;
    if (_system_impl->autopilot() == Autopilot::Px4) {
        goto_flight_mode = FlightMode::Hold;
    } else {
        goto_flight_mode = FlightMode::Offboard;
    }
    if (_system_impl->get_flight_mode() != goto_flight_mode) {
        _system_impl->set_flight_mode_async(
            goto_flight_mode,
            [this, callback, send_do_reposition](MavlinkCommandSender::Result result, float) {
                Action::Result action_result = action_result_from_command_result(result);
                if (action_result != Action::Result::Success) {
                    command_result_callback(result, callback);
                    return;
                }
                send_do_reposition();
            });
        return;
    }

    send_do_reposition();
}

void ActionImpl::do_orbit_async(
    const float radius_m,
    const float velocity_ms,
    const Action::OrbitYawBehavior yaw_behavior,
    const double latitude_deg,
    const double longitude_deg,
    const double absolute_altitude_m,
    const Action::ResultCallback& callback)
{
    MavlinkCommandSender::CommandInt command{};

    command.command = MAV_CMD_DO_ORBIT;
    command.target_component_id = _system_impl->get_autopilot_id();
    command.params.maybe_param1 = radius_m;
    command.params.maybe_param2 = velocity_ms;
    command.params.maybe_param3 = static_cast<float>(yaw_behavior);
    command.params.x = int32_t(std::round(latitude_deg * 1e7));
    command.params.y = int32_t(std::round(longitude_deg * 1e7));
    command.params.maybe_z = static_cast<float>(absolute_altitude_m);

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::hold_async(const Action::ResultCallback& callback) const
{
    _system_impl->set_flight_mode_async(
        FlightMode::Hold, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::set_actuator_async(
    const int index, const float value, const Action::ResultCallback& callback)
{
    MavlinkCommandSender::CommandLong command{};
    command.target_component_id = _system_impl->get_autopilot_id();

    if (_system_impl->autopilot() == Autopilot::ArduPilot) {
        command.command = MAV_CMD_DO_SET_SERVO;
        command.params.maybe_param1 = static_cast<float>(index);
        command.params.maybe_param2 = value;
    } else {
        auto zero_based_index = index - 1;
        if (zero_based_index >= 0) {
            command.command = MAV_CMD_DO_SET_ACTUATOR;
            switch (zero_based_index % 6) {
                case 0:
                    command.params.maybe_param1 = value;
                    break;
                case 1:
                    command.params.maybe_param2 = value;
                    break;
                case 2:
                    command.params.maybe_param3 = value;
                    break;
                case 3:
                    command.params.maybe_param4 = value;
                    break;
                case 4:
                    command.params.maybe_param5 = value;
                    break;
                case 5:
                    command.params.maybe_param6 = value;
                    break;
            }
            command.params.maybe_param7 = static_cast<float>(zero_based_index / 6);
        } else {
            if (callback) {
                _system_impl->call_user_callback([temp_callback = callback]() {
                    temp_callback(Action::Result::InvalidArgument);
                });
            }
            return;
        }
    }

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::transition_to_fixedwing_async(const Action::ResultCallback& callback) const
{
    if (!_vtol_transition_support_known) {
        if (callback) {
            callback(Action::Result::VtolTransitionSupportUnknown);
        }
        return;
    }

    if (!_vtol_transition_possible) {
        if (callback) {
            callback(Action::Result::NoVtolTransitionSupport);
        }
        return;
    }

    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_DO_VTOL_TRANSITION;
    command.params.maybe_param1 = static_cast<float>(MAV_VTOL_STATE_FW);
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::transition_to_multicopter_async(const Action::ResultCallback& callback) const
{
    if (!_vtol_transition_support_known) {
        if (callback) {
            callback(Action::Result::VtolTransitionSupportUnknown);
        }
        return;
    }

    if (!_vtol_transition_possible) {
        if (callback) {
            callback(Action::Result::NoVtolTransitionSupport);
        }
        return;
    }
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_DO_VTOL_TRANSITION;
    command.params.maybe_param1 = static_cast<float>(MAV_VTOL_STATE_MC);
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

void ActionImpl::process_extended_sys_state(const mavlink_message_t& message)
{
    mavlink_extended_sys_state_t extended_sys_state;
    mavlink_msg_extended_sys_state_decode(&message, &extended_sys_state);

    if (extended_sys_state.vtol_state != MAV_VTOL_STATE_UNDEFINED) {
        _vtol_transition_possible = true;
    } else {
        _vtol_transition_possible = false;
    }
    _vtol_transition_support_known = true;
}

void ActionImpl::set_takeoff_altitude_async(
    const float relative_altitude_m, const Action::ResultCallback& callback)
{
    callback(set_takeoff_altitude(relative_altitude_m));
}

Action::Result ActionImpl::set_takeoff_altitude(float relative_altitude_m)
{
    if (_system_impl->autopilot() == Autopilot::Px4) {
        return set_takeoff_altitude_px4(relative_altitude_m);
    } else {
        return set_takeoff_altitude_apm(relative_altitude_m);
    }
}

Action::Result ActionImpl::set_takeoff_altitude_px4(float relative_altitude_m)
{
    _takeoff_altitude = relative_altitude_m;

    const MavlinkParameterClient::Result result =
        _system_impl->set_param_float(TAKEOFF_ALT_PARAM, relative_altitude_m);
    return (result == MavlinkParameterClient::Result::Success) ? Action::Result::Success :
                                                                 Action::Result::ParameterError;
}

Action::Result ActionImpl::set_takeoff_altitude_apm(float relative_altitude_m)
{
    _takeoff_altitude = relative_altitude_m;
    return Action::Result::Success;
}

void ActionImpl::get_takeoff_altitude_async(
    const Action::GetTakeoffAltitudeCallback& callback) const
{
    auto altitude_result = get_takeoff_altitude();
    callback(altitude_result.first, altitude_result.second);
}

std::pair<Action::Result, float> ActionImpl::get_takeoff_altitude() const
{
    if (_system_impl->autopilot() == Autopilot::ArduPilot) {
        return std::make_pair<>(Action::Result::Success, _takeoff_altitude);
    } else {
        auto result = _system_impl->get_param_float(TAKEOFF_ALT_PARAM);
        return std::make_pair<>(
            (result.first == MavlinkParameterClient::Result::Success) ?
                Action::Result::Success :
                Action::Result::ParameterError,
            result.second);
    }
}

void ActionImpl::set_return_to_launch_altitude_async(
    const float relative_altitude_m, const Action::ResultCallback& callback) const
{
    callback(set_return_to_launch_altitude(relative_altitude_m));
}

Action::Result ActionImpl::set_return_to_launch_altitude(const float relative_altitude_m) const
{
    const MavlinkParameterClient::Result result =
        _system_impl->set_param_float(RTL_RETURN_ALTITUDE_PARAM, relative_altitude_m);
    return (result == MavlinkParameterClient::Result::Success) ? Action::Result::Success :
                                                                 Action::Result::ParameterError;
}

void ActionImpl::get_return_to_launch_altitude_async(
    const Action::GetReturnToLaunchAltitudeCallback& callback) const
{
    const auto get_result = get_return_to_launch_altitude();
    callback(get_result.first, get_result.second);
}

std::pair<Action::Result, float> ActionImpl::get_return_to_launch_altitude() const
{
    auto result = _system_impl->get_param_float(RTL_RETURN_ALTITUDE_PARAM);
    return std::make_pair<>(
        (result.first == MavlinkParameterClient::Result::Success) ? Action::Result::Success :
                                                                    Action::Result::ParameterError,
        result.second);
}

void ActionImpl::set_current_speed_async(float speed_m_s, const Action::ResultCallback& callback)
{
    MavlinkCommandSender::CommandLong command{};

    command.command = MAV_CMD_DO_CHANGE_SPEED;
    command.params.maybe_param1 = 1.0f; // ground speed
    command.params.maybe_param2 = speed_m_s;
    command.params.maybe_param3 = -1.0f; // no throttle set
    command.params.maybe_param4 = 0.0f; // reserved
    command.target_component_id = _system_impl->get_autopilot_id();

    _system_impl->send_command_async(
        command, [this, callback](MavlinkCommandSender::Result result, float) {
            command_result_callback(result, callback);
        });
}

Action::Result ActionImpl::set_current_speed(float speed_m_s)
{
    auto prom = std::promise<Action::Result>();
    auto fut = prom.get_future();

    set_current_speed_async(speed_m_s, [&prom](Action::Result result) { prom.set_value(result); });

    return fut.get();
}

Action::Result ActionImpl::action_result_from_command_result(MavlinkCommandSender::Result result)
{
    switch (result) {
        case MavlinkCommandSender::Result::Success:
            return Action::Result::Success;
        case MavlinkCommandSender::Result::NoSystem:
            return Action::Result::NoSystem;
        case MavlinkCommandSender::Result::ConnectionError:
            return Action::Result::ConnectionError;
        case MavlinkCommandSender::Result::Busy:
            return Action::Result::Busy;
        case MavlinkCommandSender::Result::Denied:
            // Fallthrough
        case MavlinkCommandSender::Result::TemporarilyRejected:
            return Action::Result::CommandDenied;
        case MavlinkCommandSender::Result::Failed:
            return Action::Result::Failed;
        case MavlinkCommandSender::Result::Timeout:
            return Action::Result::Timeout;
        case MavlinkCommandSender::Result::Unsupported:
            return Action::Result::Unsupported;
        default:
            return Action::Result::Unknown;
    }
}

void ActionImpl::command_result_callback(
    MavlinkCommandSender::Result command_result, const Action::ResultCallback& callback) const
{
    if (command_result == MavlinkCommandSender::Result::InProgress) {
        // We only want to return once, so we can't call the callback on progress updates.
        return;
    }

    Action::Result action_result = action_result_from_command_result(command_result);

    if (callback) {
        auto temp_callback = callback;
        _system_impl->call_user_callback(
            [temp_callback, action_result]() { temp_callback(action_result); });
    }
}

} // namespace mavsdk