joystick.hpp

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#pragma once

#include "exception.hpp"
#include "haptic.hpp"
#include "vec2.hpp"
#include <SDL_joystick.h>
#include <cassert>

namespace sdl
{
class Joystick
{
    SDL_Joystick* joystick_ = nullptr;
    const bool    owner_    = true;

    Joystick(SDL_Joystick* stick, bool owning_state) : joystick_(stick), owner_(owning_state)
    {
        assert(!owner_);
    }

public:
    Joystick() : owner_(false) {}

    Joystick(int device_index) : joystick_(SDL_JoystickOpen(device_index))
    {
        if (!joystick_) throw Exception("SDL_JoystickOpen");
    }

    Joystick(SDL_Joystick* joystick) : joystick_(joystick) {}

    Joystick(Joystick const&) = delete;
    Joystick& operator=(Joystick const&) = delete;

    Joystick(Joystick&& other) noexcept { *this = std::move(other); }

    Joystick& operator=(Joystick&& other) noexcept
    {
        if (joystick_
            != other.joystick_) // todo do we need to check owner_ here? need to think about that.
        {
            joystick_       = other.joystick_;
            other.joystick_ = nullptr;

            // this is the exceptional case when we actually want to reassign
            // the value of the "owner" boolean
            const_cast<bool&>(owner_)       = other.owner_;
            const_cast<bool&>(other.owner_) = false; // for good measure
        }
        return *this;
    }

    ~Joystick()
    {
        if (owner_ && joystick_) SDL_JoystickClose(joystick_);
    }

    Haptic open_haptic() const { return Haptic(joystick_); }

    SDL_JoystickPowerLevel power_level() const
    {
        const auto power = SDL_JoystickCurrentPowerLevel(joystick_);

        if (power == SDL_JOYSTICK_POWER_UNKNOWN) throw Exception("SDL_JoystickCurrentPowerLevel");

        return power;
    }

    bool attached() const { return SDL_JoystickGetAttached(joystick_) == SDL_TRUE; }

    int16_t get_axis(int axis) const { return SDL_JoystickGetAxis(joystick_, axis); }

    sdl::Vec2i get_ball(int ball) const
    {
        Vec2i     d;
        const int status = SDL_JoystickGetBall(joystick_, ball, &d.x, &d.y);

        if (status < 0) throw Exception("SDL_JoystickGetBall");

        return d;
    }

    uint8_t get_button(int button) const { return SDL_JoystickGetButton(joystick_, button); }

    uint8_t get_hat(int hat) const { return SDL_JoystickGetHat(joystick_, hat); }

    std::string name() const { return {SDL_JoystickName(joystick_)}; }

    int num_hats() const
    {
        const int value = SDL_JoystickNumHats(joystick_);

        if (value < 0) throw Exception("SDL_JoystickNumHats");

        return value;
    }

    int num_buttons() const
    {
        const int value = SDL_JoystickNumButtons(joystick_);

        if (value < 0) throw Exception("SDL_JoystickNumButtons");

        return value;
    }

    int num_balls() const
    {
        const int value = SDL_JoystickNumBalls(joystick_);

        if (value < 0) throw Exception("SDL_JoystickNumBalls");

        return value;
    }

    int num_axes() const
    {
        const int value = SDL_JoystickNumAxes(joystick_);

        if (value < 0) throw Exception("SDL_JoystickNumAxes");

        return value;
    }

    SDL_JoystickID instance_id() const
    {
        const auto value = SDL_JoystickInstanceID(joystick_);

        if (value < 0) throw Exception("SDL_JoystickInstanceID");

        return value;
    }

    static Joystick non_owning(SDL_Joystick* stick) { return {stick, false}; }

    static Joystick non_joystick(SDL_JoystickID joyid)
    {
        auto object = Joystick(SDL_JoystickFromInstanceID(joyid), false);

        if (object.joystick_ == nullptr) throw Exception("SDL_JoystickFromInstanceID");

        return object;
    }

    bool operator==(Joystick const& other) const { return joystick_ == other.joystick_; }

    bool operator==(SDL_Joystick* other) const { return joystick_ == other; }

    bool operator==(SDL_JoystickID other) const { return instance_id() == other; }
};
} // namespace sdl