#pragma once

/*  MOUNT CONTROL COMPONENTS LIBRARY  */

#include <atomic>
#include <concepts>
#include <cstdint>
#include <functional>
#include <string_view>

namespace mcc
{

enum class MccMountType : uint8_t { GERMAN_TYPE, FORK_TYPE, CROSSAXIS_TYPE, ALTAZ_TYPE };


// mount state type concept
template <typename T>
concept mcc_mount_state_c = requires(T t, const T t_const) {
    { t_const.ident() } -> std::same_as<std::string_view>;

    typename T::context_t;
    { t.enter(std::declval<const typename T::context_t&>()) } -> std::same_as<void>;
    { t.exit(std::declval<const typename T::context_t&>()) } -> std::same_as<void>;
};



// implements a Finite State Machine Pattern
template <MccMountType MOUNT_TYPE>
class MccMount
{
    typedef double mnt_coord_t;
    typedef double mnt_speed_t;
    typedef double time_point_t;

public:
    static constexpr MccMountType mountType = MOUNT_TYPE;

    /*  mount main-cycle variable quantities */
    struct mount_state_t {
        // time-related
        time_point_t siderTime;  // sideral time

        // target (user-input) current coordinates (in radians)
        mnt_coord_t tagRA, tagDEC;
        mnt_coord_t tagHA;
        mnt_coord_t tagAZ, tagZD;

        // encoder-measured current mount coordinates (in radians)
        mnt_coord_t mntRA, mntDEC;
        mnt_coord_t mntHA;
        mnt_coord_t mntAZ, mntZD;

        // encoder-measured current mount moving speed (in radians/s)
        mnt_speed_t mntSpeedX,
            mntSpeedY;  // X - HA, Y - DEC for equatorial-type mount; X - AZ, Y - ZD for horizontal-type one

        // current refraction coefficient
        mnt_coord_t currRefr;

        // PCS (pointing correction system) corrections
        mnt_coord_t pcsX, pcsY;  // X - HA, Y - DEC for equatorial-type mount; X - AZ, Y - ZD for horizontal-type one

        // mount current state
    };



    MccMount()
    {
        _exitCurrentState = []() {};  // do nothing
    }

    virtual ~MccMount() {}

    template <mcc_mount_state_c StateT>
    void setMountState(StateT& state)
    {
        _exitCurrentState();  // exit from current state
        _exitCurrentState = [&state, this]() { state.exit(this); };

        state.enter(this);
    }

protected:
    std::function<void()> _exitCurrentState;

    std::atomic<mount_state_t> _mountCurrentState;

    void updateMountState() {}
};

}  // namespace mcc