/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
   Lead developer: Andrew Tridgell & Tom Pittenger

   Authors:    Doug Weibel, Jose Julio, Jordi Munoz, Jason Short, Randy Mackay, Pat Hickey, John Arne Birkeland, Olivier Adler, Amilcar Lucas, Gregory Fletcher, Paul Riseborough, Brandon Jones, Jon Challinger
   Thanks to:  Chris Anderson, Michael Oborne, Paul Mather, Bill Premerlani, James Cohen, JB from rotorFX, Automatik, Fefenin, Peter Meister, Remzibi, Yury Smirnov, Sandro Benigno, Max Levine, Roberto Navoni, Lorenz Meier, Yury MonZon

   Please contribute your ideas! See http://dev.ardupilot.com for details

   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/>.
 */
#pragma once

////////////////////////////////////////////////////////////////////////////////
// Header includes
////////////////////////////////////////////////////////////////////////////////

#include <cmath>
#include <stdarg.h>
#include <stdio.h>

#include <AP_HAL/AP_HAL.h>
#include <AP_Common/AP_Common.h>
#include <AP_Menu/AP_Menu.h>
#include <AP_Param/AP_Param.h>
#include <StorageManager/StorageManager.h>
#include <AP_GPS/AP_GPS.h>         // ArduPilot GPS library
#include <AP_Baro/AP_Baro.h>        // ArduPilot barometer library
#include <AP_Compass/AP_Compass.h>     // ArduPilot Mega Magnetometer Library
#include <AP_Math/AP_Math.h>        // ArduPilot Mega Vector/Matrix math Library
#include <AP_ADC/AP_ADC.h>         // ArduPilot Mega Analog to Digital Converter Library
#include <AP_InertialSensor/AP_InertialSensor.h> // Inertial Sensor Library
#include <AP_AccelCal/AP_AccelCal.h>                // interface and maths for accelerometer calibration
#include <AP_AHRS/AP_AHRS.h>         // ArduPilot Mega DCM Library
#include <RC_Channel/RC_Channel.h>     // RC Channel Library
#include <AP_RangeFinder/AP_RangeFinder.h>     // Range finder library
#include <Filter/Filter.h>                     // Filter library
#include <AP_Buffer/AP_Buffer.h>      // APM FIFO Buffer
#include <AP_Relay/AP_Relay.h>       // APM relay
#include <AP_Camera/AP_Camera.h>          // Photo or video camera
#include <AP_Airspeed/AP_Airspeed.h>
#include <AP_Terrain/AP_Terrain.h>
#include <AP_RPM/AP_RPM.h>

#include <APM_OBC/APM_OBC.h>
#include <APM_Control/APM_Control.h>
#include <APM_Control/AP_AutoTune.h>
#include <GCS_MAVLink/GCS_MAVLink.h>    // MAVLink GCS definitions
#include <AP_SerialManager/AP_SerialManager.h>   // Serial manager library
#include <AP_Mount/AP_Mount.h>           // Camera/Antenna mount
#include <AP_Declination/AP_Declination.h> // ArduPilot Mega Declination Helper Library
#include <DataFlash/DataFlash.h>
#include <AP_Scheduler/AP_Scheduler.h>       // main loop scheduler

#include <AP_Navigation/AP_Navigation.h>
#include <AP_L1_Control/AP_L1_Control.h>
#include <AP_RCMapper/AP_RCMapper.h>        // RC input mapping library

#include <AP_Vehicle/AP_Vehicle.h>
#include <AP_SpdHgtControl/AP_SpdHgtControl.h>
#include <AP_TECS/AP_TECS.h>
#include <AP_NavEKF/AP_NavEKF.h>
#include <AP_NavEKF2/AP_NavEKF2.h>
#include <AP_Mission/AP_Mission.h>     // Mission command library

#include <AP_Notify/AP_Notify.h>      // Notify library
#include <AP_BattMonitor/AP_BattMonitor.h> // Battery monitor library

#include <AP_Arming/AP_Arming.h>
#include <AP_BoardConfig/AP_BoardConfig.h>
#include <AP_Frsky_Telem/AP_Frsky_Telem.h>
#include <AP_ServoRelayEvents/AP_ServoRelayEvents.h>

#include <AP_Rally/AP_Rally.h>

#include <AP_OpticalFlow/AP_OpticalFlow.h>     // Optical Flow library
#include <AP_RSSI/AP_RSSI.h>                   // RSSI Library
#include <AP_Parachute/AP_Parachute.h>
#include <AP_ADSB/AP_ADSB.h>

#include "GCS_Mavlink.h"
#include "quadplane.h"
#include "tuning.h"

// Configuration
#include "config.h"

// Local modules
#include "defines.h"

#include "Parameters.h"

#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
#include <SITL/SITL.h>
#endif

/*
  a plane specific arming class
 */
class AP_Arming_Plane : public AP_Arming
{
public:
    AP_Arming_Plane(const AP_AHRS &ahrs_ref, const AP_Baro &baro, Compass &compass,
                    const AP_BattMonitor &battery, const enum HomeState &home_set) :
        AP_Arming(ahrs_ref, baro, compass, battery, home_set) {
            AP_Param::setup_object_defaults(this, var_info);
    }
    bool pre_arm_checks(bool report);

    // var_info for holding Parameter information
    static const struct AP_Param::GroupInfo var_info[];
protected:
    bool ins_checks(bool report);
};

/*
  main APM:Plane class
 */
class Plane : public AP_HAL::HAL::Callbacks {
public:
    friend class GCS_MAVLINK_Plane;
    friend class Parameters;
    friend class AP_Arming_Plane;
    friend class QuadPlane;
    friend class AP_Tuning_Plane;

    Plane(void);

    // HAL::Callbacks implementation.
    void setup() override;
    void loop() override;

private:
    // key aircraft parameters passed to multiple libraries
    AP_Vehicle::FixedWing aparm;
    AP_HAL::BetterStream* cliSerial;

    // Global parameters are all contained within the 'g' class.
    Parameters g;

    // main loop scheduler
    AP_Scheduler scheduler;
 
    // mapping between input channels
    RCMapper rcmap;

    // board specific config
    AP_BoardConfig BoardConfig;

    // primary control channels
    RC_Channel *channel_roll;
    RC_Channel *channel_pitch;
    RC_Channel *channel_throttle;
    RC_Channel *channel_rudder;

    // notification object for LEDs, buzzers etc (parameter set to false disables external leds)
    AP_Notify notify;

    DataFlash_Class DataFlash;

    // has a log download started?
    bool in_log_download;

    // scaled roll limit based on pitch
    int32_t roll_limit_cd;
    int32_t pitch_limit_min_cd;

    // Sensors
    AP_GPS gps;

    // flight modes convenience array
    AP_Int8 *flight_modes = &g.flight_mode1;

    AP_Baro barometer;
    Compass compass;

    AP_InertialSensor ins;

#if RANGEFINDER_ENABLED == ENABLED
    // rangefinder
    RangeFinder rangefinder {serial_manager};

    struct {
        bool in_range:1;
        bool have_initial_reading:1;
        bool in_use:1;
        float initial_range;
        float correction;
        float initial_correction;
        float last_stable_correction;
        uint32_t last_correction_time_ms;
        uint8_t in_range_count;
        float height_estimate;
    } rangefinder_state;
#endif

    AP_RPM rpm_sensor;
    
// Inertial Navigation EKF
#if AP_AHRS_NAVEKF_AVAILABLE
    NavEKF EKF{&ahrs, barometer, rangefinder};
    NavEKF2 EKF2{&ahrs, barometer, rangefinder};
    AP_AHRS_NavEKF ahrs {ins, barometer, gps, rangefinder, EKF, EKF2};
#else
    AP_AHRS_DCM ahrs {ins, barometer, gps};
#endif

    AP_L1_Control L1_controller {ahrs};
    AP_TECS TECS_controller {ahrs, aparm};

    // Attitude to servo controllers
    AP_RollController  rollController {ahrs, aparm, DataFlash};
    AP_PitchController pitchController {ahrs, aparm, DataFlash};
    AP_YawController   yawController {ahrs, aparm};
    AP_SteerController steerController {ahrs};

#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
    SITL::SITL sitl;
#endif

    // Training mode
    bool training_manual_roll;  // user has manual roll control
    bool training_manual_pitch; // user has manual pitch control

    /*
      keep steering and rudder control separated until we update servos,
      to allow for a separate wheel servo from rudder servo
    */
    struct {
        bool ground_steering; // are we doing ground steering?
        int16_t steering; // value for nose/tail wheel
        int16_t rudder;   // value for rudder
    } steering_control;

    // should throttle be pass-thru in guided?
    bool guided_throttle_passthru;

    // are we doing calibration? This is used to allow heartbeat to
    // external failsafe boards during baro and airspeed calibration
    bool in_calibration;


    // GCS selection
    AP_SerialManager serial_manager;
    const uint8_t num_gcs = MAVLINK_COMM_NUM_BUFFERS;
    GCS_MAVLINK_Plane gcs[MAVLINK_COMM_NUM_BUFFERS];

    // selected navigation controller
    AP_Navigation *nav_controller = &L1_controller;

    // selected navigation controller
    AP_SpdHgtControl *SpdHgt_Controller = &TECS_controller;

    // Relay
    AP_Relay relay;

    // handle servo and relay events
    AP_ServoRelayEvents ServoRelayEvents {relay};

    // Camera
#if CAMERA == ENABLED
    AP_Camera camera {&relay};
#endif

#if OPTFLOW == ENABLED
    // Optical flow sensor
    OpticalFlow optflow{ahrs};
#endif

    // Rally Ponints
    AP_Rally rally {ahrs};
    
    // RSSI 
    AP_RSSI rssi;      

    // remember if USB is connected, so we can adjust baud rate
    bool usb_connected;

    // This is the state of the flight control system
    // There are multiple states defined such as MANUAL, FBW-A, AUTO
    enum FlightMode control_mode = INITIALISING;
    enum FlightMode previous_mode = INITIALISING;

    // Used to maintain the state of the previous control switch position
    // This is set to 254 when we need to re-read the switch
    uint8_t oldSwitchPosition = 254;

    // This is used to enable the inverted flight feature
    bool inverted_flight;

    // This is used to enable the PX4IO override for testing
    bool px4io_override_enabled;

    struct {
        // These are trim values used for elevon control
        // For elevons radio_in[CH_ROLL] and radio_in[CH_PITCH] are
        // equivalent aileron and elevator, not left and right elevon
        uint16_t trim1;
        uint16_t trim2;
        // These are used in the calculation of elevon1_trim and elevon2_trim
        uint16_t ch1_temp;
        uint16_t ch2_temp;
    } elevon { 1500, 1500, 1500, 1500 };

    // Failsafe
    struct {
        // Used to track if the value on channel 3 (throtttle) has fallen below the failsafe threshold
        // RC receiver should be set up to output a low throttle value when signal is lost
        uint8_t ch3_failsafe:1;

        // has the saved mode for failsafe been set?
        uint8_t saved_mode_set:1;

        // flag to hold whether battery low voltage threshold has been breached
        uint8_t low_battery:1;

        // saved flight mode
        enum FlightMode saved_mode;

        // A tracking variable for type of failsafe active
        // Used for failsafe based on loss of RC signal or GCS signal
        int16_t state;

        // number of low ch3 values
        uint8_t ch3_counter;

        // the time when the last HEARTBEAT message arrived from a GCS
        uint32_t last_heartbeat_ms;
        
        // A timer used to track how long we have been in a "short failsafe" condition due to loss of RC signal
        uint32_t ch3_timer_ms;
        
        uint32_t last_valid_rc_ms;

        //keeps track of the last valid rc as it relates to the AFS system
        //Does not count rc inputs as valid if the standard failsafe is on
        uint32_t AFS_last_valid_rc_ms;
    } failsafe;

    // A counter used to count down valid gps fixes to allow the gps estimate to settle
    // before recording our home position (and executing a ground start if we booted with an air start)
    uint8_t ground_start_count = 5;

    // true if we have a position estimate from AHRS
    bool have_position;

    // Airspeed
    // The calculated airspeed to use in FBW-B.  Also used in higher modes for insuring min ground speed is met.
    // Also used for flap deployment criteria.  Centimeters per second.
    int32_t target_airspeed_cm;

    // The difference between current and desired airspeed.  Used in the pitch controller.  Meters per second.
    float airspeed_error;

    // An amount that the airspeed should be increased in auto modes based on the user positioning the
    // throttle stick in the top half of the range.  Centimeters per second.
    int16_t airspeed_nudge_cm;

    // Similar to airspeed_nudge, but used when no airspeed sensor.
    // 0-(throttle_max - throttle_cruise) : throttle nudge in Auto mode using top 1/2 of throttle stick travel
    int16_t throttle_nudge;

    // receiver RSSI
    uint8_t receiver_rssi;

    // Ground speed
    // The amount current ground speed is below min ground speed.  Centimeters per second
    int32_t groundspeed_undershoot;

    // Difference between current altitude and desired altitude.  Centimeters
    int32_t altitude_error_cm;

    // Battery Sensors
    AP_BattMonitor battery;

#if FRSKY_TELEM_ENABLED == ENABLED
    // FrSky telemetry support
    AP_Frsky_Telem frsky_telemetry {ahrs, battery};
#endif

    // Airspeed Sensors
    AP_Airspeed airspeed {aparm};

    // ACRO controller state
    struct {
        bool locked_roll;
        bool locked_pitch;
        float locked_roll_err;
        int32_t locked_pitch_cd;
    } acro_state;

    // CRUISE controller state
    struct {
        bool locked_heading;
        int32_t locked_heading_cd;
        uint32_t lock_timer_ms;
    } cruise_state;

    struct {
        uint32_t last_tkoff_arm_time;
        uint32_t last_check_ms;
        uint32_t last_report_ms;
        bool launchTimerStarted;
    } takeoff_state;
    
    // ground steering controller state
    struct {
        // Direction held during phases of takeoff and landing centidegrees
        // A value of -1 indicates the course has not been set/is not in use
        // this is a 0..36000 value, or -1 for disabled
        int32_t hold_course_cd;

        // locked_course and locked_course_cd are used in stabilize mode 
        // when ground steering is active, and for steering in auto-takeoff
        bool locked_course;
        float locked_course_err;
    } steer_state { -1, false, 0 };

    // flight mode specific
    struct {
        // Flag for using gps ground course instead of INS yaw.  Set false when takeoff command in process.
        bool takeoff_complete:1;

        // Flag to indicate if we have landed.
        // Set land_complete if we are within 2 seconds distance or within 3 meters altitude of touchdown
        bool land_complete:1;

        // Flag to indicate if we have triggered pre-flare. This occurs when we have reached LAND_PF_ALT
        bool land_pre_flare:1;

        // are we in auto and flight mode is approach || pre-flare || final (flare)
        bool land_in_progress:1;

        // should we fly inverted?
        bool inverted_flight:1;

        // should we disable cross-tracking for the next waypoint?
        bool next_wp_no_crosstrack:1;

        // should we use cross-tracking for this waypoint?
        bool no_crosstrack:1;

        // in FBWA taildragger takeoff mode
        bool fbwa_tdrag_takeoff_mode:1;

        // have we checked for an auto-land?
        bool checked_for_autoland:1;

        // denotes if a go-around has been commanded for landing
        bool commanded_go_around:1;

        // Altitude threshold to complete a takeoff command in autonomous modes.  Centimeters
        // are we in idle mode? used for balloon launch to stop servo
        // movement until altitude is reached
        bool idle_mode:1;

        // used to 'wiggle' servos in idle mode to prevent them freezing
        // at high altitudes
        uint8_t idle_wiggle_stage;

        // Altitude threshold to complete a takeoff command in autonomous
        // modes.  Centimeters above home
        int32_t takeoff_altitude_rel_cm;

        // Minimum pitch to hold during takeoff command execution.  Hundredths of a degree
        int16_t takeoff_pitch_cd;

        // Begin leveling out the enforced takeoff pitch angle min at this height to reduce/eliminate overshoot
        int32_t height_below_takeoff_to_level_off_cm;

        // the highest airspeed we have reached since entering AUTO. Used
        // to control ground takeoff
        float highest_airspeed;
        
        // initial pitch. Used to detect if nose is rising in a tail dragger
        int16_t initial_pitch_cd;
        
        // turn angle for next leg of mission
        float next_turn_angle {90};

        // filtered sink rate for landing
        float sink_rate;

        // time when we first pass min GPS speed on takeoff
        uint32_t takeoff_speed_time_ms;
        
        // distance to next waypoint
        float wp_distance;
        
        // proportion to next waypoint
        float wp_proportion;
        
        // last time is_flying() returned true in milliseconds
        uint32_t last_flying_ms;

        // once landed, post some landing statistics to the GCS
        bool post_landing_stats;

        // time stamp of when we start flying while in auto mode in milliseconds
        uint32_t started_flying_in_auto_ms;

        // calculated approach slope during auto-landing: ((prev_WP_loc.alt - next_WP_loc.alt)*0.01f - aparm.land_flare_sec * sink_rate) / get_distance(prev_WP_loc, next_WP_loc)
        float land_slope;

        // same as land_slope but sampled once before a rangefinder changes the slope. This should be the original mission planned slope
        float initial_land_slope;

        // barometric altitude at start of takeoff
        float baro_takeoff_alt;

        // are we in VTOL mode in AUTO?
        bool vtol_mode:1;

        // are we doing loiter mode as a VTOL?
        bool vtol_loiter:1;
    } auto_state;

    struct {
        // on hard landings, only check once after directly a landing so you
        // don't trigger a crash when picking up the aircraft
        bool checkedHardLanding:1;

        // crash detection. True when we are crashed
        bool is_crashed:1;

        // impact detection flag. Expires after a few seconds via impact_timer_ms
        bool impact_detected:1;

        // debounce timer
        uint32_t debounce_timer_ms;

        // delay time for debounce to count to
        uint32_t debounce_time_total_ms;

        // length of time impact_detected has been true. Times out after a few seconds. Used to clip isFlyingProbability
        uint32_t impact_timer_ms;
    } crash_state;

    // true if we are in an auto-throttle mode, which means
    // we need to run the speed/height controller
    bool auto_throttle_mode;

    // this controls throttle suppression in auto modes
    bool throttle_suppressed;

    // reduce throttle to eliminate battery over-current
    int8_t  throttle_watt_limit_max;
    int8_t  throttle_watt_limit_min; // for reverse thrust
    uint32_t throttle_watt_limit_timer_ms;

    AP_SpdHgtControl::FlightStage flight_stage = AP_SpdHgtControl::FLIGHT_NORMAL;

    // probability of aircraft is currently in flight. range from 0 to
    // 1 where 1 is 100% sure we're in flight
    float isFlyingProbability;

    // previous value of is_flying()
    bool previous_is_flying;

    // time since started flying in any mode in milliseconds
    uint32_t started_flying_ms;

    // Navigation control variables
    // The instantaneous desired bank angle.  Hundredths of a degree
    int32_t nav_roll_cd;

    // The instantaneous desired pitch angle.  Hundredths of a degree
    int32_t nav_pitch_cd;

    // we separate out rudder input to allow for RUDDER_ONLY=1
    int16_t rudder_input;

    // the aerodymamic load factor. This is calculated from the demanded
    // roll before the roll is clipped, using 1/sqrt(cos(nav_roll))
    float aerodynamic_load_factor = 1.0f;

    // a smoothed airspeed estimate, used for limiting roll angle
    float smoothed_airspeed;

    // Mission library
    AP_Mission mission {ahrs, 
            FUNCTOR_BIND_MEMBER(&Plane::start_command_callback, bool, const AP_Mission::Mission_Command &),
            FUNCTOR_BIND_MEMBER(&Plane::verify_command_callback, bool, const AP_Mission::Mission_Command &),
            FUNCTOR_BIND_MEMBER(&Plane::exit_mission_callback, void)};


#if PARACHUTE == ENABLED
    AP_Parachute parachute {relay};
#endif

    // terrain handling
#if AP_TERRAIN_AVAILABLE
    AP_Terrain terrain {ahrs, mission, rally};
#endif

    AP_ADSB adsb {ahrs};
    struct {

        // flag to signify the current mode is set by ADSB evasion logic
        bool is_evading:1;

        // generic timestamp for evasion algorithms
        uint32_t timestamp_ms;

        // previous wp to restore to when switching between modes back to AUTO
        Location prev_wp;
    } adsb_state;


    // Outback Challenge Failsafe Support
#if OBC_FAILSAFE == ENABLED
    APM_OBC obc {mission, barometer, gps, rcmap};
#endif

    /*
      meta data to support counting the number of circles in a loiter
    */
    struct {
        // previous target bearing, used to update sum_cd
        int32_t old_target_bearing_cd;

        // Total desired rotation in a loiter.  Used for Loiter Turns commands. 
        int32_t total_cd;

        // total angle completed in the loiter so far
        int32_t sum_cd;

        // Direction for loiter. 1 for clockwise, -1 for counter-clockwise
        int8_t direction;

        // start time of the loiter.  Milliseconds.
        uint32_t start_time_ms;

        // The amount of time we should stay in a loiter for the Loiter Time command.  Milliseconds.
        uint32_t time_max_ms;
    } loiter;


    // Conditional command
    // A value used in condition commands (eg delay, change alt, etc.)
    // For example in a change altitude command, it is the altitude to change to.
    int32_t condition_value;

    // A starting value used to check the status of a conditional command.
    // For example in a delay command the condition_start records that start time for the delay
    uint32_t condition_start;
    // A value used in condition commands.  For example the rate at which to change altitude.
    int16_t condition_rate;

    // 3D Location vectors
    // Location structure defined in AP_Common
    const struct Location &home = ahrs.get_home();

    // Flag for if we have g_gps lock and have set the home location in AHRS
    enum HomeState home_is_set = HOME_UNSET;

    // The location of the previous waypoint.  Used for track following and altitude ramp calculations
    Location prev_WP_loc {};

    // The plane's current location
    struct Location current_loc {};

    // The location of the current/active waypoint.  Used for altitude ramp, track following and loiter calculations.
    Location next_WP_loc {};

    // The location of the active waypoint in Guided mode.
    struct Location guided_WP_loc {};

    // Altitude control
    struct {
        // target altitude above sea level in cm. Used for barometric
        // altitude navigation
        int32_t amsl_cm;

        // Altitude difference between previous and current waypoint in
        // centimeters. Used for glide slope handling
        int32_t offset_cm;

#if AP_TERRAIN_AVAILABLE
        // are we trying to follow terrain?
        bool terrain_following;

        // target altitude above terrain in cm, valid if terrain_following
        // is set
        int32_t terrain_alt_cm;

        // lookahead value for height error reporting
        float lookahead;
#endif
    } target_altitude {};

    // INS variables
    // The main loop execution time.  Seconds
    // This is the time between calls to the DCM algorithm and is the Integration time for the gyros.
    float G_Dt = 0.02f;

    struct {
        // Performance monitoring
        // Timer used to accrue data and trigger recording of the performanc monitoring log message
        uint32_t start_ms;

        // The maximum and minimum main loop execution time recorded in the current performance monitoring interval
        uint32_t G_Dt_max;
        uint32_t G_Dt_min;

        // System Timers
        // Time in microseconds of start of main control loop
        uint32_t fast_loopTimer_us;

        // Number of milliseconds used in last main loop cycle
        uint32_t delta_us_fast_loop;

        // Counter of main loop executions.  Used for performance monitoring and failsafe processing
        uint16_t mainLoop_count;

        // number of long loops
        uint16_t num_long;

        // accumulated lost log messages
        uint32_t last_log_dropped;
    } perf;

    // Camera/Antenna mount tracking and stabilisation stuff
#if MOUNT == ENABLED
    // current_loc uses the baro/gps soloution for altitude rather than gps only.
    AP_Mount camera_mount {ahrs, current_loc};
#endif

    // Arming/Disarming mangement class
    AP_Arming_Plane arming {ahrs, barometer, compass, battery, home_is_set };

    AP_Param param_loader {var_info};

    static const AP_Scheduler::Task scheduler_tasks[];
    static const AP_Param::Info var_info[];

    bool demoing_servos = false;

    // use this to prevent recursion during sensor init
    bool in_mavlink_delay = false;

    // true if we are out of time in our event timeslice
    bool gcs_out_of_time = false;

    // time that rudder arming has been running
    uint32_t rudder_arm_timer;

    // support for quadcopter-plane
    QuadPlane quadplane{ahrs};

    // support for transmitter tuning
    AP_Tuning_Plane tuning;

    static const struct LogStructure log_structure[];
    
#if CONFIG_HAL_BOARD == HAL_BOARD_PX4
    // the crc of the last created PX4Mixer
    int32_t last_mixer_crc = -1;
#endif // CONFIG_HAL_BOARD
    
    void demo_servos(uint8_t i);
    void adjust_nav_pitch_throttle(void);
    void update_load_factor(void);
    void send_heartbeat(mavlink_channel_t chan);
    void send_attitude(mavlink_channel_t chan);
    void send_fence_status(mavlink_channel_t chan);
    void send_extended_status1(mavlink_channel_t chan);
    void send_location(mavlink_channel_t chan);
    void send_nav_controller_output(mavlink_channel_t chan);
    void send_position_target_global_int(mavlink_channel_t chan);
    void send_servo_out(mavlink_channel_t chan);
    void send_radio_out(mavlink_channel_t chan);
    void send_vfr_hud(mavlink_channel_t chan);
    void send_simstate(mavlink_channel_t chan);
    void send_hwstatus(mavlink_channel_t chan);
    void send_wind(mavlink_channel_t chan);
    void send_pid_tuning(mavlink_channel_t chan);
    void send_rpm(mavlink_channel_t chan);
    void send_rangefinder(mavlink_channel_t chan);
    void send_current_waypoint(mavlink_channel_t chan);
    bool telemetry_delayed(mavlink_channel_t chan);
    void gcs_send_message(enum ap_message id);
    void gcs_send_mission_item_reached_message(uint16_t mission_index);
    void gcs_data_stream_send(void);
    void gcs_update(void);
    void gcs_send_text(MAV_SEVERITY severity, const char *str);
    void gcs_send_airspeed_calibration(const Vector3f &vg);
    void gcs_retry_deferred(void);

    void do_erase_logs(void);
    void Log_Write_Fast(void);
    void Log_Write_Attitude(void);
    void Log_Write_Performance();
    void Log_Write_Startup(uint8_t type);
    void Log_Write_Control_Tuning();
    void Log_Write_Nav_Tuning();
    void Log_Write_Status();
    void Log_Write_Sonar();
    void Log_Write_Optflow();
    void Log_Write_Current();
    void Log_Arm_Disarm();
    void Log_Write_GPS(uint8_t instance);
    void Log_Write_IMU();
    void Log_Write_RC(void);
    void Log_Write_Baro(void);
    void Log_Write_Airspeed(void);
    void Log_Write_Home_And_Origin();
    void Log_Write_Vehicle_Startup_Messages();
    void Log_Read(uint16_t log_num, int16_t start_page, int16_t end_page);
    void start_logging();

    void load_parameters(void);
    void adjust_altitude_target();
    void setup_glide_slope(void);
    int32_t get_RTL_altitude();
    float relative_altitude(void);
    int32_t relative_altitude_abs_cm(void);
    float relative_ground_altitude(bool use_rangefinder_if_available);
    void set_target_altitude_current(void);
    void set_target_altitude_current_adjusted(void);
    void set_target_altitude_location(const Location &loc);
    int32_t relative_target_altitude_cm(void);
    void change_target_altitude(int32_t change_cm);
    void set_target_altitude_proportion(const Location &loc, float proportion);
    void constrain_target_altitude_location(const Location &loc1, const Location &loc2);
    int32_t calc_altitude_error_cm(void);
    void check_minimum_altitude(void);
    void reset_offset_altitude(void);
    void set_offset_altitude_location(const Location &loc);
    bool above_location_current(const Location &loc);
    void setup_terrain_target_alt(Location &loc);
    int32_t adjusted_altitude_cm(void);
    int32_t adjusted_relative_altitude_cm(void);
    float height_above_target(void);
    float lookahead_adjustment(void);
    float rangefinder_correction(void);
    void rangefinder_height_update(void);
    void set_next_WP(const struct Location &loc);
    void set_guided_WP(void);
    void init_home();
    void update_home();
    void do_RTL(int32_t alt);
    bool verify_takeoff();
    bool verify_loiter_unlim();
    bool verify_loiter_time();
    bool verify_loiter_turns();
    bool verify_loiter_to_alt();
    bool verify_RTL();
    bool verify_continue_and_change_alt();
    bool verify_wait_delay();
    bool verify_within_distance();
    bool verify_altitude_wait(const AP_Mission::Mission_Command &cmd);
    bool verify_vtol_takeoff(const AP_Mission::Mission_Command &cmd);
    bool verify_vtol_land(const AP_Mission::Mission_Command &cmd);
    void do_loiter_at_location();
    void do_take_picture();
    bool verify_loiter_heading(bool init);
    void log_picture();
    void exit_mission_callback();
    void mavlink_delay(uint32_t ms);
    void read_control_switch();
    uint8_t readSwitch(void);
    void reset_control_switch();
    void autotune_start(void);
    void autotune_restore(void);
    void autotune_enable(bool enable);
    bool fly_inverted(void);
    void failsafe_short_on_event(enum failsafe_state fstype);
    void failsafe_long_on_event(enum failsafe_state fstype);
    void failsafe_short_off_event();
    void low_battery_event(void);
    void update_events(void);
    uint8_t max_fencepoints(void);
    Vector2l get_fence_point_with_index(unsigned i);
    void set_fence_point_with_index(Vector2l &point, unsigned i);
    void geofence_load(void);
    bool geofence_present(void);
    void geofence_update_pwm_enabled_state();
    bool geofence_set_enabled(bool enable, GeofenceEnableReason r);
    bool geofence_enabled(void);
    bool geofence_set_floor_enabled(bool floor_enable);
    bool geofence_check_minalt(void);
    bool geofence_check_maxalt(void);
    void geofence_check(bool altitude_check_only);
    bool geofence_stickmixing(void);
    void geofence_send_status(mavlink_channel_t chan);
    bool geofence_breached(void);
    bool verify_land();
    void disarm_if_autoland_complete();
    void setup_landing_glide_slope(void);
    void adjust_landing_slope_for_rangefinder_bump(void);
    bool jump_to_landing_sequence(void);
    float tecs_hgt_afe(void);
    void set_nav_controller(void);
    void loiter_angle_reset(void);
    void loiter_angle_update(void);
    void navigate();
    void calc_airspeed_errors();
    void calc_gndspeed_undershoot();
    void update_loiter(uint16_t radius);
    void update_cruise();
    void update_fbwb_speed_height(void);
    void setup_turn_angle(void);
    bool reached_loiter_target(void);
    bool print_buffer(char *&buf, uint16_t &buf_size, const char *fmt, ...);
    uint16_t create_mixer(char *buf, uint16_t buf_size, const char *filename);
    bool setup_failsafe_mixing(void);
    void set_control_channels(void);
    void init_rc_in();
    void init_rc_out();
    void rudder_arm_disarm_check();
    void read_radio();
    void control_failsafe(uint16_t pwm);
    void trim_control_surfaces();
    void trim_radio();
    bool rc_failsafe_active(void);
    void init_barometer(bool full_calibration);
    void init_rangefinder(void);
    void read_rangefinder(void);
    void read_airspeed(void);
    void zero_airspeed(bool in_startup);
    void read_battery(void);
    void read_receiver_rssi(void);
    void rpm_update(void);
    void report_radio();
    void report_ins();
    void report_compass();
    void print_radio_values();
    void print_done();
    void print_blanks(int16_t num);
    void print_divider(void);
    void zero_eeprom(void);
    void print_enabled(bool b);
    void print_accel_offsets_and_scaling(void);
    void print_gyro_offsets(void);
    void init_ardupilot();
    void startup_ground(void);
    enum FlightMode get_previous_mode();
    void set_mode(enum FlightMode mode);
    bool mavlink_set_mode(uint8_t mode);
    void exit_mode(enum FlightMode mode);
    void check_long_failsafe();
    void check_short_failsafe();
    void startup_INS_ground(void);
    void update_notify();
    void resetPerfData(void);
    void check_usb_mux(void);
    void print_comma(void);
    void servo_write(uint8_t ch, uint16_t pwm);
    bool should_log(uint32_t mask);
    void frsky_telemetry_send(void);
    int8_t throttle_percentage(void);
    void change_arm_state(void);
    bool disarm_motors(void);
    bool arm_motors(AP_Arming::ArmingMethod method);
    bool auto_takeoff_check(void);
    void takeoff_calc_roll(void);
    void takeoff_calc_pitch(void);
    int8_t takeoff_tail_hold(void);
    int16_t get_takeoff_pitch_min_cd(void);
    void print_hit_enter();
    void ahrs_update();
    void update_speed_height(void);
    void update_GPS_50Hz(void);
    void update_GPS_10Hz(void);
    void update_compass(void);
    void update_alt(void);
    void obc_fs_check(void);
    void compass_accumulate(void);
    void compass_cal_update();
    void barometer_accumulate(void);
    void update_optical_flow(void);
    void one_second_loop(void);
    void airspeed_ratio_update(void);
    void update_mount(void);
    void update_trigger(void);    
    void log_perf_info(void);
    void compass_save(void);
    void update_logging1(void);
    void update_logging2(void);
    void terrain_update(void);
    void adsb_update(void);
    bool adsb_evasion_start(void);
    void adsb_evasion_stop(void);
    void adsb_evasion_ongoing(void);
    void update_flight_mode(void);
    void stabilize();
    void set_servos_idle(void);
    void set_servos();
    bool allow_reverse_thrust(void);
    void update_aux();
    void update_is_flying_5Hz(void);
    void crash_detection_update(void);
    bool in_preLaunch_flight_stage(void);
    void gcs_send_text_fmt(MAV_SEVERITY severity, const char *fmt, ...);
    void handle_auto_mode(void);
    void calc_throttle();
    void calc_nav_roll();
    void calc_nav_pitch();
    void update_flight_stage();
    void update_navigation();
    void set_flight_stage(AP_SpdHgtControl::FlightStage fs);
    bool is_flying(void);
    float get_speed_scaler(void);
    bool stick_mixing_enabled(void);
    void stabilize_roll(float speed_scaler);
    void stabilize_pitch(float speed_scaler);
    static void stick_mix_channel(RC_Channel *channel);
    static void stick_mix_channel(RC_Channel *channel, int16_t &servo_out);
    void stabilize_stick_mixing_direct();
    void stabilize_stick_mixing_fbw();
    void stabilize_yaw(float speed_scaler);
    void stabilize_training(float speed_scaler);
    void stabilize_acro(float speed_scaler);
    void calc_nav_yaw_coordinated(float speed_scaler);
    void calc_nav_yaw_course(void);
    void calc_nav_yaw_ground(void);
    void throttle_slew_limit(int16_t last_throttle);
    void flap_slew_limit(int8_t &last_value, int8_t &new_value);
    bool suppress_throttle(void);
    void channel_output_mixer(uint8_t mixing_type, int16_t & chan1, int16_t & chan2)const;
    void channel_output_mixer(uint8_t mixing_type, RC_Channel* chan1, RC_Channel* chan2)const;
    void flaperon_update(int8_t flap_percent);
    bool start_command(const AP_Mission::Mission_Command& cmd);
    bool verify_command(const AP_Mission::Mission_Command& cmd);
    void do_takeoff(const AP_Mission::Mission_Command& cmd);
    void do_nav_wp(const AP_Mission::Mission_Command& cmd);
    void do_land(const AP_Mission::Mission_Command& cmd);
    void loiter_set_direction_wp(const AP_Mission::Mission_Command& cmd);
    void do_loiter_unlimited(const AP_Mission::Mission_Command& cmd);
    void do_loiter_turns(const AP_Mission::Mission_Command& cmd);
    void do_loiter_time(const AP_Mission::Mission_Command& cmd);
    void do_altitude_wait(const AP_Mission::Mission_Command& cmd);
    void do_continue_and_change_alt(const AP_Mission::Mission_Command& cmd);
    void do_loiter_to_alt(const AP_Mission::Mission_Command& cmd);
    void do_vtol_takeoff(const AP_Mission::Mission_Command& cmd);
    void do_vtol_land(const AP_Mission::Mission_Command& cmd);
    bool verify_nav_wp(const AP_Mission::Mission_Command& cmd);
    void do_wait_delay(const AP_Mission::Mission_Command& cmd);
    void do_within_distance(const AP_Mission::Mission_Command& cmd);
    void do_change_speed(const AP_Mission::Mission_Command& cmd);
    void do_set_home(const AP_Mission::Mission_Command& cmd);
    void do_digicam_configure(const AP_Mission::Mission_Command& cmd);
    void do_digicam_control(const AP_Mission::Mission_Command& cmd);
    bool start_command_callback(const AP_Mission::Mission_Command &cmd);
    bool verify_command_callback(const AP_Mission::Mission_Command& cmd);
    void print_flight_mode(AP_HAL::BetterStream *port, uint8_t mode);
    void run_cli(AP_HAL::UARTDriver *port);
    bool restart_landing_sequence();
    void log_init();
    void init_capabilities(void);
    void dataflash_periodic(void);
    uint16_t throttle_min(void) const;
    void do_parachute(const AP_Mission::Mission_Command& cmd);
    void parachute_check();
    void parachute_release();
    bool parachute_manual_release();
    void accel_cal_update(void);

public:
    void mavlink_delay_cb();
    void failsafe_check(void);
    bool print_log_menu(void);
    int8_t dump_log(uint8_t argc, const Menu::arg *argv);
    int8_t erase_logs(uint8_t argc, const Menu::arg *argv);
    int8_t select_logs(uint8_t argc, const Menu::arg *argv);
    int8_t process_logs(uint8_t argc, const Menu::arg *argv);
    int8_t setup_mode(uint8_t argc, const Menu::arg *argv);
    int8_t setup_factory(uint8_t argc, const Menu::arg *argv);
    int8_t setup_erase(uint8_t argc, const Menu::arg *argv);
    int8_t test_mode(uint8_t argc, const Menu::arg *argv);
    int8_t reboot_board(uint8_t argc, const Menu::arg *argv);
    int8_t main_menu_help(uint8_t argc, const Menu::arg *argv);
    int8_t test_radio_pwm(uint8_t argc, const Menu::arg *argv);
    int8_t test_passthru(uint8_t argc, const Menu::arg *argv);
    int8_t test_radio(uint8_t argc, const Menu::arg *argv);
    int8_t test_failsafe(uint8_t argc, const Menu::arg *argv);
    int8_t test_relay(uint8_t argc, const Menu::arg *argv);
    int8_t test_wp(uint8_t argc, const Menu::arg *argv);
    void test_wp_print(const AP_Mission::Mission_Command& cmd);
    int8_t test_xbee(uint8_t argc, const Menu::arg *argv);
    int8_t test_modeswitch(uint8_t argc, const Menu::arg *argv);
    int8_t test_logging(uint8_t argc, const Menu::arg *argv);
    int8_t test_gps(uint8_t argc, const Menu::arg *argv);
    int8_t test_ins(uint8_t argc, const Menu::arg *argv);
    int8_t test_mag(uint8_t argc, const Menu::arg *argv);
    int8_t test_airspeed(uint8_t argc, const Menu::arg *argv);
    int8_t test_pressure(uint8_t argc, const Menu::arg *argv);
    int8_t test_shell(uint8_t argc, const Menu::arg *argv);
};

#define MENU_FUNC(func) FUNCTOR_BIND(&plane, &Plane::func, int8_t, uint8_t, const Menu::arg *)

extern const AP_HAL::HAL& hal;
extern Plane plane;

using AP_HAL::millis;
using AP_HAL::micros;
