#pragma once

#include "Sub.h"
class Parameters;
class ParametersG2;

class GCS_Sub;

// Guided modes
enum GuidedSubMode {
    Guided_WP,
    Guided_Velocity,
    Guided_PosVel,
    Guided_Angle,
};

// Auto modes
enum AutoSubMode {
    Auto_WP,
    Auto_CircleMoveToEdge,
    Auto_Circle,
    Auto_NavGuided,
    Auto_Loiter,
    Auto_TerrainRecover
};

// RTL states
enum RTLState {
    RTL_InitialClimb,
    RTL_ReturnHome,
    RTL_LoiterAtHome,
    RTL_FinalDescent,
    RTL_Land
};

class Mode
{

public:

    // Auto Pilot Modes enumeration
    enum class Number : uint8_t {
        STABILIZE =     0,  // manual angle with manual depth/throttle
        ACRO =          1,  // manual body-frame angular rate with manual depth/throttle
        ALT_HOLD =      2,  // manual angle with automatic depth/throttle
        AUTO =          3,  // fully automatic waypoint control using mission commands
        GUIDED =        4,  // fully automatic fly to coordinate or fly at velocity/direction using GCS immediate commands
        CIRCLE =        7,  // automatic circular flight with automatic throttle
        SURFACE =       9,  // automatically return to surface, pilot maintains horizontal control
        POSHOLD =      16,  // automatic position hold with manual override, with automatic throttle
        MANUAL =       19,  // Pass-through input with no stabilization
        MOTOR_DETECT = 20,  // Automatically detect motors orientation
        SURFTRAK =     21   // Track distance above seafloor (hold range)
    };

    // constructor
    Mode(void);

    // do not allow copying
    CLASS_NO_COPY(Mode);

    // child classes should override these methods
    virtual bool init(bool ignore_checks) { return true; }
    virtual void run() = 0;
    virtual bool requires_GPS() const = 0;
    virtual bool has_manual_throttle() const = 0;
    virtual bool allows_arming(bool from_gcs) const = 0;
    virtual bool is_autopilot() const { return false; }
    virtual bool in_guided_mode() const { return false; }

    // return a string for this flightmode
    virtual const char *name() const = 0;
    virtual const char *name4() const = 0;

    // functions for reporting to GCS
    virtual bool get_wp(Location &loc) { return false; }
    virtual int32_t wp_bearing() const { return 0; }
    virtual uint32_t wp_distance() const { return 0; }
    virtual float crosstrack_error() const { return 0.0f; }

  
    // pilot input processing
    void get_pilot_desired_accelerations(float &right_out, float &front_out) const;
    void get_pilot_desired_angle_rates(int16_t roll_in, int16_t pitch_in, int16_t yaw_in, float &roll_out, float &pitch_out, float &yaw_out);


protected:

    // navigation support functions
    virtual void run_autopilot() {}

    // helper functions
    bool is_disarmed_or_landed() const;

    // functions to control landing
    // in modes that support landing
    void land_run_horizontal_control();
    void land_run_vertical_control(bool pause_descent = false);

    // convenience references to avoid code churn in conversion:
    Parameters &g;
    ParametersG2 &g2;
    AP_InertialNav &inertial_nav;
    AP_AHRS &ahrs;
    AP_Motors6DOF &motors;
    RC_Channel *&channel_roll;
    RC_Channel *&channel_pitch;
    RC_Channel *&channel_throttle;
    RC_Channel *&channel_yaw;
    RC_Channel *&channel_forward;
    RC_Channel *&channel_lateral;
    AC_PosControl *position_control;
    AC_AttitudeControl_Sub *attitude_control;
    // TODO: channels
    float &G_Dt;

public:
    // Navigation Yaw control
    class AutoYaw
    {

    public:
        // mode(): current method of determining desired yaw:
        autopilot_yaw_mode mode() const
        {
            return (autopilot_yaw_mode)_mode;
        }
        void set_mode_to_default(bool rtl);
        void set_mode(autopilot_yaw_mode new_mode);
        autopilot_yaw_mode default_mode(bool rtl) const;

        void set_rate(float new_rate_cds);

        // set_roi(...): set a "look at" location:
        void set_roi(const Location &roi_location);

        void set_fixed_yaw(float angle_deg,
                           float turn_rate_dps,
                           int8_t direction,
                           bool relative_angle);

    private:

        // yaw_cd(): main product of AutoYaw; the heading:
        float yaw_cd();

        // rate_cds(): desired yaw rate in centidegrees/second:
        float rate_cds();

        float look_ahead_yaw();
        float roi_yaw();

        // auto flight mode's yaw mode
        uint8_t _mode = AUTO_YAW_LOOK_AT_NEXT_WP;

        // Yaw will point at this location if mode is set to AUTO_YAW_ROI
        Vector3f roi;

        // bearing from current location to the ROI
        float _roi_yaw;

        // yaw used for YAW_FIXED yaw_mode
        int32_t _fixed_yaw;

        // Deg/s we should turn
        int16_t _fixed_yaw_slewrate;

        // heading when in yaw_look_ahead_yaw
        float _look_ahead_yaw;

        // used to reduce update rate to 100hz:
        uint8_t roi_yaw_counter;

        GuidedSubMode guided_mode;

    };
    static AutoYaw auto_yaw;

    // pass-through functions to reduce code churn on conversion;
    // these are candidates for moving into the Mode base
    // class.
    bool set_mode(Mode::Number mode, ModeReason reason);
    GCS_Sub &gcs();

    // end pass-through functions
};

class ModeManual : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;
    virtual void run() override;
    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return false; }
    bool has_manual_throttle() const override { return true; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return false; }

protected:

    const char *name() const override { return "MANUAL"; }
    const char *name4() const override { return "MANU"; }
};


class ModeAcro : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return false; }
    bool has_manual_throttle() const override { return true; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return false; }

protected:

    const char *name() const override { return "ACRO"; }
    const char *name4() const override { return "ACRO"; }
};


class ModeStabilize : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return false; }
    bool has_manual_throttle() const override { return true; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return false; }

protected:

    const char *name() const override { return "STABILIZE"; }
    const char *name4() const override { return "STAB"; }
};


class ModeAlthold : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return false; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return false; }
    void control_depth();

protected:

    void run_pre();
    void run_post();

    const char *name() const override { return "ALT_HOLD"; }
    const char *name4() const override { return "ALTH"; }
};


class ModeSurftrak : public ModeAlthold
{

public:
    // constructor
    ModeSurftrak();

    void run() override;

    bool init(bool ignore_checks) override;

    float get_rangefinder_target_cm() const WARN_IF_UNUSED { return rangefinder_target_cm; }
    bool set_rangefinder_target_cm(float target_cm);

protected:

    const char *name() const override { return "SURFTRAK"; }
    const char *name4() const override { return "STRK"; }

private:

    void reset();
    void control_range();
    void update_surface_offset();

    float rangefinder_target_cm;

    bool pilot_in_control;            // pilot is moving up/down
    float pilot_control_start_z_cm;   // alt when pilot took control
};

class ModeGuided : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return true; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }
    bool guided_limit_check();
    void guided_limit_init_time_and_pos();
    void guided_set_angle(const Quaternion &q, float climb_rate_cms, bool use_yaw_rate, float yaw_rate_rads);
    void guided_set_angle(const Quaternion&, float);
    void guided_limit_set(uint32_t timeout_ms, float alt_min_cm, float alt_max_cm, float horiz_max_cm);
    bool guided_set_destination_posvel(const Vector3f& destination, const Vector3f& velocity);
    bool guided_set_destination_posvel(const Vector3f& destination, const Vector3f& velocity, bool use_yaw, float yaw_cd, bool use_yaw_rate, float yaw_rate_cds, bool relative_yaw);
    bool guided_set_destination(const Vector3f& destination);
    bool guided_set_destination(const Location&);
    bool guided_set_destination(const Vector3f& destination, bool use_yaw, float yaw_cd, bool use_yaw_rate, float yaw_rate_cds, bool relative_yaw);
    void guided_set_velocity(const Vector3f& velocity);
    void guided_set_velocity(const Vector3f& velocity, bool use_yaw, float yaw_cd, bool use_yaw_rate, float yaw_rate_cds, bool relative_yaw);
    void guided_set_yaw_state(bool use_yaw, float yaw_cd, bool use_yaw_rate, float yaw_rate_cds, bool relative_angle);
    float get_auto_heading();
    void guided_limit_clear();
    void set_auto_yaw_mode(autopilot_yaw_mode yaw_mode);

protected:

    const char *name() const override { return "GUIDED"; }
    const char *name4() const override { return "GUID"; }
    autopilot_yaw_mode get_default_auto_yaw_mode(bool rtl) const;

private:
    void guided_pos_control_run();
    void guided_vel_control_run();
    void guided_posvel_control_run();
    void guided_angle_control_run();
    void guided_takeoff_run();
    void guided_pos_control_start();
    void guided_vel_control_start();
    void guided_posvel_control_start();
    void guided_angle_control_start();
};



class ModeAuto : public ModeGuided
{

public:
    // inherit constructor
    using ModeGuided::ModeGuided;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return true; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }
    bool auto_loiter_start();
    void auto_wp_start(const Vector3f& destination);
    void auto_wp_start(const Location& dest_loc);
    void auto_circle_movetoedge_start(const Location &circle_center, float radius_m, bool ccw_turn);
    void auto_circle_start();
    void auto_nav_guided_start();
    void set_auto_yaw_roi(const Location &roi_location);
    void set_auto_yaw_look_at_heading(float angle_deg, float turn_rate_dps, int8_t direction, uint8_t relative_angle);
    void set_yaw_rate(float turn_rate_dps);
    bool auto_terrain_recover_start();

protected:

    const char *name() const override { return "AUTO"; }
    const char *name4() const override { return "AUTO"; }

private:
    void auto_wp_run();
    void auto_circle_run();
    void auto_nav_guided_run();
    void auto_loiter_run();
    void auto_terrain_recover_run();
};


class ModePoshold : public ModeAlthold
{

public:
    // inherit constructor
    using ModeAlthold::ModeAlthold;

    virtual void run() override;

    bool init(bool ignore_checks) override;

    bool requires_GPS() const override { return false; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }

protected:

    const char *name() const override { return "POSHOLD"; }
    const char *name4() const override { return "POSH"; }
};


class ModeCircle : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return true; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }

protected:

    const char *name() const override { return "CIRCLE"; }
    const char *name4() const override { return "CIRC"; }
};

class ModeSurface : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return true; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }

protected:

    const char *name() const override { return "SURFACE"; }
    const char *name4() const override { return "SURF"; }
};


class ModeMotordetect : public Mode
{

public:
    // inherit constructor
    using Mode::Mode;

    virtual void run() override;

    bool init(bool ignore_checks) override;
    bool requires_GPS() const override { return true; }
    bool has_manual_throttle() const override { return false; }
    bool allows_arming(bool from_gcs) const override { return true; }
    bool is_autopilot() const override { return true; }

protected:

    const char *name() const override { return "MOTORDETECT"; }
    const char *name4() const override { return "DETE"; }
};