ardupilot/libraries/AP_DDS/AP_DDS_Client.h

#pragma once

#if AP_DDS_ENABLED

#include "uxr/client/client.h"
#include "ucdr/microcdr.h"
#include "builtin_interfaces/msg/Time.h"
#include "AP_DDS_Generic_Fn_T.h"

#include "sensor_msgs/msg/NavSatFix.h"
#include "tf2_msgs/msg/TFMessage.h"
#include "sensor_msgs/msg/BatteryState.h"
#include "geometry_msgs/msg/PoseStamped.h"
#include "geometry_msgs/msg/TwistStamped.h"

#include <AP_HAL/AP_HAL.h>
#include <AP_HAL/Scheduler.h>
#include <AP_HAL/Semaphores.h>
#include <AP_AHRS/AP_AHRS.h>

#include "fcntl.h"

#include <AP_Param/AP_Param.h>

#define DDS_STREAM_HISTORY 8
#define DDS_BUFFER_SIZE 512

// UDP only on SITL for now
#define AP_DDS_UDP_ENABLED (CONFIG_HAL_BOARD == HAL_BOARD_SITL)

#if AP_DDS_UDP_ENABLED
#include <AP_HAL/utility/Socket.h>
#endif

extern const AP_HAL::HAL& hal;

class AP_DDS_Client
{

private:

    AP_Int8 enabled;

    // Serial Allocation
    uxrSession session; //Session
    bool is_using_serial; // true when using serial transport

    // input and output stream
    uint8_t *input_reliable_stream;
    uint8_t *output_reliable_stream;
    uxrStreamId reliable_in;
    uxrStreamId reliable_out;

    // Topic
    builtin_interfaces_msg_Time time_topic;
    sensor_msgs_msg_NavSatFix nav_sat_fix_topic;
    tf2_msgs_msg_TFMessage static_transforms_topic;
    sensor_msgs_msg_BatteryState battery_state_topic;
    geometry_msgs_msg_PoseStamped local_pose_topic;
    geometry_msgs_msg_TwistStamped local_velocity_topic;

    HAL_Semaphore csem;

    // connection parametrics
    bool connected = true;

    static void update_topic(builtin_interfaces_msg_Time& msg);
    bool update_topic(sensor_msgs_msg_NavSatFix& msg, const uint8_t instance) WARN_IF_UNUSED;
    static void populate_static_transforms(tf2_msgs_msg_TFMessage& msg);
    static void update_topic(sensor_msgs_msg_BatteryState& msg, const uint8_t instance);
    static void update_topic(geometry_msgs_msg_PoseStamped& msg);
    static void update_topic(geometry_msgs_msg_TwistStamped& msg);

    // The last ms timestamp AP_DDS wrote a Time message
    uint64_t last_time_time_ms;
    // The last ms timestamp AP_DDS wrote a NavSatFix message
    uint64_t last_nav_sat_fix_time_ms;
    // The last ms timestamp AP_DDS wrote a BatteryState message
    uint64_t last_battery_state_time_ms;
    // The last ms timestamp AP_DDS wrote a Local Pose message
    uint64_t last_local_pose_time_ms;
    // The last ms timestamp AP_DDS wrote a Local Velocity message
    uint64_t last_local_velocity_time_ms;

    // functions for serial transport
    bool ddsSerialInit();
    static bool serial_transport_open(uxrCustomTransport* args);
    static bool serial_transport_close(uxrCustomTransport* transport);
    static size_t serial_transport_write(uxrCustomTransport* transport, const uint8_t* buf, size_t len, uint8_t* error);
    static size_t serial_transport_read(uxrCustomTransport* transport, uint8_t* buf, size_t len, int timeout, uint8_t* error);
    struct {
        AP_HAL::UARTDriver *port;
        uxrCustomTransport transport;
    } serial;

#if AP_DDS_UDP_ENABLED
    // functions for udp transport
    bool ddsUdpInit();
    static bool udp_transport_open(uxrCustomTransport* args);
    static bool udp_transport_close(uxrCustomTransport* transport);
    static size_t udp_transport_write(uxrCustomTransport* transport, const uint8_t* buf, size_t len, uint8_t* error);
    static size_t udp_transport_read(uxrCustomTransport* transport, uint8_t* buf, size_t len, int timeout, uint8_t* error);

    struct {
        AP_Int32 port;
        // UDP endpoint
        const char* ip = "127.0.0.1";
        // UDP Allocation
        uxrCustomTransport transport;
        SocketAPM *socket;
    } udp;
#endif

    // client key we present
    static constexpr uint32_t uniqueClientKey = 0xAAAABBBB;

public:
    bool start(void);
    void main_loop(void);

    //! @brief Initialize the client's transport, uxr session, and IO stream(s)
    //! @return True on successful initialization, false on failure
    bool init() WARN_IF_UNUSED;

    //! @brief Set up the client's participants, data read/writes,
    //         publishers, subscribers
    //! @return True on successful creation, false on failure
    bool create() WARN_IF_UNUSED;

    //! @brief Serialize the current time state and publish to the IO stream(s)
    void write_time_topic();
    //! @brief Serialize the current nav_sat_fix state and publish to the IO stream(s)
    void write_nav_sat_fix_topic();
    //! @brief Serialize the static transforms and publish to the IO stream(s)
    void write_static_transforms();
    //! @brief Serialize the current nav_sat_fix state and publish it to the IO stream(s)
    void write_battery_state_topic();
    //! @brief Serialize the current local pose and publish to the IO stream(s)
    void write_local_pose_topic();
    //! @brief Serialize the current local velocity and publish to the IO stream(s)
    void write_local_velocity_topic();
    //! @brief Update the internally stored DDS messages with latest data
    void update();

    //! @brief Parameter storage
    static const struct AP_Param::GroupInfo var_info[];

    //! @brief Convenience grouping for a single "channel" of data
    struct Topic_table {
        const uint8_t topic_id;
        const uint8_t pub_id;
        const uxrObjectId dw_id;
        const char* topic_profile_label;
        const char* dw_profile_label;
        Generic_serialize_topic_fn_t serialize;
        Generic_deserialize_topic_fn_t deserialize;
        Generic_size_of_topic_fn_t size_of;
    };
    static const struct Topic_table topics[];


};

#endif // AP_DDS_ENABLED