/*
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
/*
  implementation of Robotis Dynamixel 2.0 protocol for controlling servos
 */

#pragma once

#include <AP_HAL/AP_HAL.h>
#include <AP_Param/AP_Param.h>

class AP_RobotisServo {
public:
    AP_RobotisServo();

    /* Do not allow copies */
    AP_RobotisServo(const AP_RobotisServo &other) = delete;
    AP_RobotisServo &operator=(const AP_RobotisServo&) = delete;

    static const struct AP_Param::GroupInfo var_info[];
    
    void update();

private:
    AP_HAL::UARTDriver *port;
    uint32_t baudrate;
    uint32_t us_per_byte;
    uint32_t us_gap;

    void init(void);
    void detect_servos();

    uint16_t update_crc(uint16_t crc_accum, uint8_t *data_blk_ptr, uint16_t data_blk_size);
    void add_stuffing(uint8_t *packet);
    void send_packet(uint8_t *txpacket);
    void read_bytes();
    void process_packet(const uint8_t *pkt, uint8_t length);
    void send_command(uint8_t id, uint16_t reg, uint32_t value, uint8_t len);
    void configure_servos(void);

    // auto-detected mask of available servos, from a broadcast ping
    uint16_t servo_mask;
    uint8_t detection_count;
    uint8_t configured_servos;
    bool initialised;

    uint8_t pktbuf[64];
    uint8_t pktbuf_ofs;

    // servo position limits
    AP_Int32 pos_min;
    AP_Int32 pos_max;

    uint32_t last_send_us;
    uint32_t delay_time_us;
};
