#pragma once

/*                          MOUNT CONTROL COMPONENTS LIBRARY                            */



/*                          SOME LIBRARY-WIDE DECLARATIONS                          */


#include <chrono>
#include <concepts>


// #include "mcc_traits.h"
#include "mcc_angle.h"

namespace mcc
{


// mount construction type (only the most common ones)
enum class MccMountType : uint8_t { GERMAN_TYPE, FORK_TYPE, CROSSAXIS_TYPE, ALTAZ_TYPE };

template <MccMountType TYPE>
static constexpr std::string_view MccMountTypeStr = TYPE == MccMountType::GERMAN_TYPE      ? "GERMAN"
                                                    : TYPE == MccMountType::FORK_TYPE      ? "FORK"
                                                    : TYPE == MccMountType::CROSSAXIS_TYPE ? "CROSSAXIS"
                                                    : TYPE == MccMountType::ALTAZ_TYPE     ? "ALTAZ"
                                                                                           : "UNKNOWN";

template <MccMountType TYPE>
static constexpr bool mcc_is_equatorial_mount = TYPE == MccMountType::GERMAN_TYPE      ? true
                                                : TYPE == MccMountType::FORK_TYPE      ? true
                                                : TYPE == MccMountType::CROSSAXIS_TYPE ? true
                                                : TYPE == MccMountType::ALTAZ_TYPE     ? false
                                                                                       : false;
template <MccMountType TYPE>
static constexpr bool mcc_is_altaz_mount = TYPE == MccMountType::GERMAN_TYPE      ? false
                                           : TYPE == MccMountType::FORK_TYPE      ? false
                                           : TYPE == MccMountType::CROSSAXIS_TYPE ? false
                                           : TYPE == MccMountType::ALTAZ_TYPE     ? true
                                                                                  : false;

static consteval bool mccIsEquatorialMount(const MccMountType type)
{
    return type == MccMountType::GERMAN_TYPE      ? true
           : type == MccMountType::FORK_TYPE      ? true
           : type == MccMountType::CROSSAXIS_TYPE ? true
           : type == MccMountType::ALTAZ_TYPE     ? false
                                                  : false;
};

static consteval bool mccIsAltAzMount(const MccMountType type)
{
    return type == MccMountType::GERMAN_TYPE      ? false
           : type == MccMountType::FORK_TYPE      ? false
           : type == MccMountType::CROSSAXIS_TYPE ? false
           : type == MccMountType::ALTAZ_TYPE     ? true
                                                  : false;
};



// enum MccCoordPairKind : size_t {
//     COORDS_KIND_GENERIC,
//     COORDS_KIND_RADEC_ICRS,
//     COORDS_KIND_RADEC_APP,
//     COORDS_KIND_HADEC_APP,
//     COORDS_KIND_AZZD,
//     COORDS_KIND_AZALT,
//     COORDS_KIND_XY,
//     COORDS_KIND_LATLON
// };


/*                          FLOATING-POINT LIKE CLASS CONCEPT                           */

template <typename T>
concept mcc_fp_type_like_c =
    std::floating_point<T> ||
    (std::convertible_to<T, double> && std::constructible_from<T, double> && std::default_initializable<T>);


/*                          ANGLE REPRESENTATION CLASS CONCEPT                           */

template <typename T>
concept mcc_angle_c = mcc_fp_type_like_c<T> && requires(T v, double vd) {
    // mandatory arithmetic operations
    { v + v } -> std::same_as<T>;
    { v - v } -> std::same_as<T>;
    { v += v } -> std::same_as<T&>;
    { v -= v } -> std::same_as<T&>;

    { vd + v } -> std::same_as<T>;
    { vd - v } -> std::same_as<T>;
    { v + vd } -> std::same_as<T>;
    { v - vd } -> std::same_as<T>;
    { v += vd } -> std::same_as<T&>;
    { v -= vd } -> std::same_as<T&>;

    { v * vd } -> std::same_as<T>;
    { v / vd } -> std::same_as<T>;
};


/*                          TIME POINT CLASS CONCEPT                           */

/*
 *  USE OF STL std::chrono::time_point
 */
template <typename T>
concept mcc_time_point_c = traits::mcc_systime_c<T>;
// concept mcc_time_point_c = requires(T t) { []<typename CT, typename DT>(std::chrono::time_point<CT, DT>) {}(t); };


/*                          JULIAN DAY CLASS CONCEPT                            */

template <typename T>
concept mcc_julday_c = mcc_fp_type_like_c<T> && requires(const T v) {
    // modified Julian Day
    { v.MJD() } -> std::convertible_to<double>;
    // comparison operators
    v <=> v;
};


/*                          ERROR CLASS CONCEPT                            */

template <typename T>
concept mcc_error_c = std::convertible_to<T, bool> || requires(const T t) {
    { t.operator bool() };
};


template <mcc_error_c ErrT, typename DErrT>
static constexpr ErrT mcc_deduce_error(const DErrT& err, const ErrT& default_err)
{
    if constexpr (std::same_as<ErrT, DErrT>) {
        return err;
    } else {
        return default_err;
    }
}



/*                          ATMOSPHERIC REFRACTION MODEL CLASS CONCEPT                            */

template <typename T>
concept mcc_refract_model_c = requires(const T t_const) {
    { t_const.name() } -> std::formattable<char>;
};


/*                          CELESTIAL POINT WITH A PAIR OF COORDINATES CLASS CONCEPT                           */

template <typename T>
concept mcc_celestial_point_c = requires(T t) {
    requires std::same_as<decltype(t.pair_kind), MccCoordPairKind>;  // type of given coordinate pair

    requires mcc_time_point_c<decltype(t.time_point)>;  // time point for given coordinates

    requires mcc_angle_c<decltype(t.X)>;  // co-longitude (X-axis)
    requires mcc_angle_c<decltype(t.Y)>;  // co-latitude (Y-axis)
};


static constexpr void mcc_copy_celestial_point(mcc_celestial_point_c auto const& from_pt,
                                               mcc_celestial_point_c auto* to_pt)
{
    if (to_pt == nullptr) {
        return;
    }

    using from_pt_t = std::remove_cvref_t<decltype(from_pt)>;
    using to_pt_t = std::remove_cvref_t<decltype(*to_pt)>;

    if constexpr (std::derived_from<to_pt_t, from_pt_t> && std::copyable<to_pt_t>) {
        *to_pt = from_pt;
        return;
    }

    to_pt->pair_kind = from_pt.pair_kind;
    to_pt->time_point =
        std::chrono::time_point_cast<typename decltype(to_pt->time_point)::duration>(from_pt.time_point);
    to_pt->X = (double)from_pt.X;
    to_pt->Y = (double)from_pt.Y;
}


/*                          CELESTIAL POINT WITH APPARENT EQUATORIAL AND HORIZONTAL CLASS CONCEPT */

template <typename T>
concept mcc_eqt_hrz_coord_c = mcc_celestial_point_c<T> && requires(T t) {
    requires mcc_angle_c<decltype(t.RA_APP)>;   // right ascension
    requires mcc_angle_c<decltype(t.DEC_APP)>;  // declination
    requires mcc_angle_c<decltype(t.HA)>;       // hour angle
    requires mcc_angle_c<decltype(t.AZ)>;   // azimuth (NOTE: ASSUMING THE AZINUTH IS COUNTED FROM THE SOUTH THROUGH THE
                                            // WEST!!!)
    requires mcc_angle_c<decltype(t.ZD)>;   // zenithal distance
    requires mcc_angle_c<decltype(t.ALT)>;  // altitude
};


static constexpr void mcc_copy_eqt_hrz_coord(mcc_eqt_hrz_coord_c auto const& from_pt, mcc_eqt_hrz_coord_c auto* to_pt)
{
    if (to_pt == nullptr) {
        return;
    }

    using from_pt_t = std::remove_cvref_t<decltype(from_pt)>;
    using to_pt_t = std::remove_cvref_t<decltype(*to_pt)>;

    if constexpr (std::derived_from<to_pt_t, from_pt_t> && std::copyable<to_pt_t>) {
        *to_pt = from_pt;
        return;
    }

    to_pt->pair_kind = from_pt.pair_kind;
    to_pt->time_point =
        std::chrono::time_point_cast<typename decltype(to_pt->time_point)::duration>(from_pt.time_point);
    to_pt->X = (double)from_pt.X;
    to_pt->Y = (double)from_pt.Y;

    to_pt->RA_APP = (double)from_pt.RA_APP;
    to_pt->DEC_APP = (double)from_pt.DEC_APP;

    to_pt->HA = (double)from_pt.HA;
    to_pt->AZ = (double)from_pt.AZ;
    to_pt->ZD = (double)from_pt.ZD;
    to_pt->ALT = (double)from_pt.ALT;
}


/*                          CELESTIAL COORDINATES TRANSFORMATION ENGINE     */


template <mcc_error_c RetT>
struct mcc_CCTE_interface_t {
    virtual ~mcc_CCTE_interface_t() = default;

    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT timepointToJulday(this SelfT&& self, mcc_time_point_c auto tp, mcc_julday_c auto* julday)
    {
        return std::forward<SelfT>(self).timepointToJulday(std::move(tp), julday);
    }

    // APPARENT SIDERAL TIME
    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT timepointToAppSideral(this SelfT&& self, mcc_time_point_c auto tp, mcc_angle_c auto* st, bool islocal = false)
    {
        return std::forward<SelfT>(self).timepointToAppSideral(std::move(tp), st, islocal);
    }

    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT juldayToAppSideral(this SelfT&& self, mcc_julday_c auto jd, mcc_angle_c auto* st, bool islocal = false)
    {
        return std::forward<SelfT>(self).timepointToAppSideral(std::move(jd), st, islocal);
    }

    // NOTE: ASSUMING THE AZINUTH IS COUNTED FROM THE SOUTH THROUGH THE WEST!!!
    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT transformCoordinates(this SelfT&& self, mcc_celestial_point_c auto from_pt, mcc_celestial_point_c auto* to_pt)
    {
        return std::forward<SelfT>(self).transformCoordinates(std::move(from_pt), to_pt);
    }

    // NOTE: ASSUMING THE AZIMUTH IS COUNTED FROM THE SOUTH THROUGH THE WEST!!!
    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT transformCoordinates(this SelfT&& self, mcc_celestial_point_c auto from_pt, mcc_eqt_hrz_coord_c auto* to_pt)
    {
        return std::forward<SelfT>(self).transformCoordinates(std::move(from_pt), to_pt);
    }

    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT parallacticAngle(this SelfT&& self, mcc_celestial_point_c auto pt, mcc_angle_c auto* pa)
    {
        return std::forward<SelfT>(self).parallacticAngle(std::move(pt), pa);
    }

    template <std::derived_from<mcc_CCTE_interface_t> SelfT>
    RetT refractionCorrection(this SelfT&& self, mcc_celestial_point_c auto pt, mcc_angle_c auto* dZ)
    {
        return std::forward<SelfT>(self).refractionCoeff(std::move(pt), dZ);
    }

protected:
    mcc_CCTE_interface_t() = default;
};


template <typename T>
concept mcc_ccte_c = std::derived_from<T, mcc_CCTE_interface_t<typename T::error_t>> && requires(const T t_const, T t) {
    { t_const.name() } -> std::formattable<char>;

    requires mcc_refract_model_c<typename T::refract_model_t>;

    { t.refractionModel(std::declval<typename T::refract_model_t*>()) } -> std::same_as<typename T::error_t>;
};



/*                          MOUNT TELEMETRY DATA CLASS CONCEPT  */

template <typename T>
concept mcc_pointing_target_coord_c = mcc_eqt_hrz_coord_c<T> && requires(T t) {
    requires mcc_angle_c<decltype(t.RA_ICRS)>;   // ICRS right ascention
    requires mcc_angle_c<decltype(t.DEC_ICRS)>;  // ICRS declination
};


static constexpr void mcc_copy_pointing_target_coord(mcc_pointing_target_coord_c auto const& from_pt,
                                                     mcc_pointing_target_coord_c auto* to_pt)
{
    if (to_pt == nullptr) {
        return;
    }

    using from_pt_t = std::remove_cvref_t<decltype(from_pt)>;
    using to_pt_t = std::remove_cvref_t<decltype(*to_pt)>;

    if constexpr (std::derived_from<to_pt_t, from_pt_t> && std::copyable<to_pt_t>) {
        *to_pt = from_pt;
        return;
    }

    to_pt->pair_kind = from_pt.pair_kind;
    to_pt->time_point =
        std::chrono::time_point_cast<typename decltype(to_pt->time_point)::duration>(from_pt.time_point);
    to_pt->X = (double)from_pt.X;
    to_pt->Y = (double)from_pt.Y;

    to_pt->RA_ICRS = (double)from_pt.RA_ICRS;
    to_pt->DEC_ICRS = (double)from_pt.DEC_ICRS;

    to_pt->RA_APP = (double)from_pt.RA_APP;
    to_pt->DEC_APP = (double)from_pt.DEC_APP;

    to_pt->HA = (double)from_pt.HA;
    to_pt->AZ = (double)from_pt.AZ;
    to_pt->ZD = (double)from_pt.ZD;
    to_pt->ALT = (double)from_pt.ALT;
}



template <typename T>
concept mcc_telemetry_data_c = mcc_eqt_hrz_coord_c<T> && std::default_initializable<T> && requires(T t) {
    // target target coordinates
    requires mcc_pointing_target_coord_c<decltype(t.target)>;

    // t.X and t.Y (from mcc_celestial_point_c) are encoder coordinates
    // t.* from mcc_eqt_hrz_coord_c are apparent mount pointing coordinates
    requires mcc_angle_c<decltype(t.speedX)>;  // speed along X from hardware encoder
    requires mcc_angle_c<decltype(t.speedY)>;  // speed along Y from hardware encoder

    // corrections to transform hardware encoder coordinates to apparent celestial ones
    requires mcc_angle_c<decltype(t.pcmX)>;  // PCM correction along X-axis
    requires mcc_angle_c<decltype(t.pcmY)>;  // PCM correction along Y-axis

    // atmospheric refraction correction for current zenithal distance
    requires mcc_angle_c<decltype(t.refCorr)>;  // for current .ZD
};


static constexpr void mcc_copy_telemetry_data(mcc_telemetry_data_c auto const& from_pt,
                                              mcc_telemetry_data_c auto* to_pt)
{
    if (to_pt == nullptr) {
        return;
    }

    using from_pt_t = std::remove_cvref_t<decltype(from_pt)>;
    using to_pt_t = std::remove_cvref_t<decltype(*to_pt)>;

    if constexpr (std::derived_from<to_pt_t, from_pt_t> && std::copyable<to_pt_t>) {
        *to_pt = from_pt;
        return;
    }

    to_pt->pair_kind = from_pt.pair_kind;
    to_pt->time_point =
        std::chrono::time_point_cast<typename decltype(to_pt->time_point)::duration>(from_pt.time_point);

    to_pt->X = (double)from_pt.X;
    to_pt->Y = (double)from_pt.Y;
    to_pt->speedX = (double)from_pt.speedX;
    to_pt->speedY = (double)from_pt.speedY;

    to_pt->RA_APP = (double)from_pt.RA_APP;
    to_pt->DEC_APP = (double)from_pt.DEC_APP;

    to_pt->HA = (double)from_pt.HA;
    to_pt->AZ = (double)from_pt.AZ;
    to_pt->ZD = (double)from_pt.ZD;
    to_pt->ALT = (double)from_pt.ALT;

    to_pt->pcmX = (double)from_pt.pcmX;
    to_pt->pcmY = (double)from_pt.pcmY;

    to_pt->refCorr = (double)from_pt.refCorr;

    mcc_copy_pointing_target_coord(from_pt.target, &to_pt->target);
}



/*                          MOUNT TELEMETRY MANAGER CLASS CONCEPT                   */

template <mcc_error_c RetT>
struct mcc_telemetry_interface_t {
    virtual ~mcc_telemetry_interface_t() = default;

    template <std::derived_from<mcc_telemetry_interface_t> SelfT>
    RetT telemetryData(this SelfT&& self, mcc_telemetry_data_c auto* data)
    {
        return std::forward<SelfT>(self).telemetryData(data);
    }

    template <std::derived_from<mcc_telemetry_interface_t> SelfT>
    RetT setPointingTarget(this SelfT&& self, mcc_celestial_point_c auto pt)
    {
        return std::forward<SelfT>(self).telemetryData(std::move(pt));
    }

protected:
    mcc_telemetry_interface_t() = default;
};

template <typename T>
concept mcc_telemetry_c = std::derived_from<T, mcc_telemetry_interface_t<typename T::error_t>>;



/*                          POINTING CORRECTION MODEL CLASS CONCEPT                 */

template <typename T>
concept mcc_PCM_result_c = requires(T t) {
    requires mcc_angle_c<decltype(t.dx)>;
    requires mcc_angle_c<decltype(t.dy)>;
};

template <mcc_error_c RetT, mcc_PCM_result_c ResT>
struct mcc_PCM_interface_t {
    template <std::derived_from<mcc_PCM_interface_t> SelfT>
    RetT computePCM(this SelfT&& self, mcc_celestial_point_c auto pt, ResT* result)
    {
        return std::forward<SelfT>(self).computePCM(std::move(pt), result);
    }
};

template <typename T>
concept mcc_PCM_c =
    std::derived_from<T, mcc_PCM_interface_t<typename T::error_t, typename T::pcm_result_t>> && requires {
        // the 'T' class must contain static constexpr member of 'MccMountType' type
        requires std::same_as<decltype(T::mountType), const MccMountType>;
        []() {
            static constexpr MccMountType val = T::mountType;
            return val;
        }();  // to ensure 'mountType' can be used in compile-time context
    };



/*                          MOUNT HARDWARE ABSTRACTION CLASS CONCEPT                            */

template <typename T>
concept mcc_hardware_c = requires(T t, const T t_const) {
    typename T::error_t;

    { t_const.name() } -> std::formattable<char>;

    // a class that contains at least time point of measurement, coordinates for x,y axes and its moving rates
    requires requires(typename T::axes_pos_t pos) {
        requires mcc_time_point_c<decltype(pos.time_point)>;  // time point

        requires mcc_angle_c<decltype(pos.X)>;  // target or current co-longitude coordinate
        requires mcc_angle_c<decltype(pos.Y)>;  // target or current co-latitude coordinate

        requires mcc_angle_c<decltype(pos.speedX)>;
        requires mcc_angle_c<decltype(pos.speedY)>;
    };

    // set positions (angles) of mount axes with given speeds
    // NOTE: exact interpretation (or even ignoring) of the given moving speeds is subject of a hardware-class
    // implementation.
    //       e.g. it can be maximal speeds at slewing ramp
    { t.setPos(std::declval<typename T::axes_pos_t>()) } -> std::same_as<typename T::error_t>;

    // get current positions and speeds (angles) of mount axes
    { t.getPos(std::declval<typename T::axes_pos_t*>()) } -> std::same_as<typename T::error_t>;

    { t.stop() } -> std::same_as<typename T::error_t>;  // stop any moving
    { t.init() } -> std::same_as<typename T::error_t>;  // initialize hardware
};



/*                          PROHIBITED ZONE CLASS CONCEPT                           */

template <mcc_error_c RetT>
struct mcc_pzone_interface_t {
    virtual ~mcc_pzone_interface_t() = default;

    template <std::derived_from<mcc_pzone_interface_t> SelfT, typename InputT>
    RetT inPZone(this SelfT&& self, InputT coords, bool* result)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>) &&
                requires { self.inPZone(coords, result); }
    {
        return std::forward<SelfT>(self).InPZone(std::move(coords), result);
    }


    template <std::derived_from<mcc_pzone_interface_t> SelfT, typename InputT>
    RetT timeToPZone(this SelfT&& self, InputT coords, traits::mcc_time_duration_c auto* res_time)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>) &&
                requires { self.timeToPZone(coords, res_time); }
    {
        return std::forward<SelfT>(self).timeToPZone(std::move(coords), res_time);
    }

    template <std::derived_from<mcc_pzone_interface_t> SelfT, typename InputT>
    RetT timeFromPZone(this SelfT&& self, InputT coords, traits::mcc_time_duration_c auto* res_time)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>) &&
                requires { self.timeFromPZone(coords, res_time); }
    {
        return std::forward<SelfT>(self).timeFromPZone(std::move(coords), res_time);
    }

    //
    // NOTE: the method must return:
    //     point = mcc_celestial_point_c{.pair_kind = MccCoordPairKind::COORDS_KIND_GENERIC, .X = NaN, .Y = NaN}
    //             if there is no intersection with the zone for given coordinates!
    template <std::derived_from<mcc_pzone_interface_t> SelfT, typename InputT>
    RetT intersectPZone(this SelfT&& self, InputT coords, mcc_celestial_point_c auto* point)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>) &&
                requires { self.intersectPZone(coords, point); }
    {
        return std::forward<SelfT>(self).intersectPZone(std::move(coords), point);
    }

protected:
    mcc_pzone_interface_t() = default;
};


template <typename T>
concept mcc_prohibited_zone_c =
    std::derived_from<T, mcc_pzone_interface_t<typename T::error_t>> && requires(const T t_const) {
        { t_const.name() } -> std::formattable<char>;
    };


/*                          PROHIBITED ZONES CONTAINER CLASS CONCEPT                           */


template <mcc_error_c RetT>
struct mcc_pzone_container_interface_t {
    virtual ~mcc_pzone_container_interface_t() = default;


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT>
    size_t addPZone(this SelfT&& self, mcc_prohibited_zone_c auto zone)
    {
        return std::forward<SelfT>(self).addPZone(std::move(zone));
    }


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT>
    void clearPZones(this SelfT&& self)
    {
        return std::forward<SelfT>(self).clearPZones();
    }


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT>
    size_t sizePZones(this SelfT&& self)
    {
        return std::forward<SelfT>(self).sizePZones();
    }


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT, typename InputT>
    RetT inPZone(this SelfT&& self, InputT coords, bool* common_result, std::ranges::output_range<bool> auto* result)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>)
    {
        return std::forward<SelfT>(self).InPZone(std::move(coords), common_result, result);
    }


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT, typename InputT, traits::mcc_time_duration_c DT>
    RetT timeToPZone(this SelfT&& self, InputT coords, std::ranges::output_range<DT> auto* res_time)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>)
    {
        return std::forward<SelfT>(self).timeToPZone(std::move(coords), res_time);
    }

    template <std::derived_from<mcc_pzone_container_interface_t> SelfT, typename InputT, traits::mcc_time_duration_c DT>
    RetT timeFromPZone(this SelfT&& self, InputT coords, std::ranges::output_range<DT> auto* res_time)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>)
    {
        return std::forward<SelfT>(self).timeFromPZone(std::move(coords), res_time);
    }


    template <std::derived_from<mcc_pzone_container_interface_t> SelfT, typename InputT, mcc_celestial_point_c CPT>
    RetT intersectPZone(this SelfT&& self, InputT coords, std::ranges::output_range<CPT> auto* result)
        requires(mcc_eqt_hrz_coord_c<InputT> || mcc_celestial_point_c<InputT>)
    {
        return std::forward<SelfT>(self).intersectPZone(std::move(coords), result);
    }

protected:
    mcc_pzone_container_interface_t() = default;
};


template <typename T>
concept mcc_pzone_container_c = std::derived_from<T, mcc_pzone_container_interface_t<typename T::error_t>>;


}  // namespace mcc