gates_of_skeldal/platform/sdl/sdl_context.h

#pragma once

#include <memory>
#include <optional>
#include <SDL.h>
#include <thread>
#include <mutex>
#include <vector>
#include <libs/mouse.h>
#include <functional>
#include "unique_value.h"

#include <queue>

class SDLContext {
public:

    SDLContext();

    enum class CrtFilterType {
        none,
        autoselect,
        scanlines,
        scanlines_2,
        rgb_matrix_2,
        rgb_matrix_3

    };

    struct VideoConfig {
        int window_width;
        int window_height;
        CrtFilterType  crt_filter;
        int composer;
        const char *scale_quality;
        bool fullscreen;
        int aspect_x;
        int aspect_y;
    };

    struct AudioConfig {
        const char *audioDevice;
    };

    enum class JoystickButton : char{
        disabled,
        enter,
        space,
        ctrl,
        lclick,
        rclick,
        ctrl_lclick,
        escape,
        up,
        down,
        left,
        right,
        turn_left,
        turn_right,
        merge,
        split1,
        split2,
        split3,
        split4,
        split5,
        split6,
        map,
        F1,
        F2,
        F3,
        F4,
        F5,
        F6,
        F7,
        F8,
        F9,
        F10,
        F11,
        F12,
        backspace,
        mod_key
    };

    static JoystickButton button_from_string(std::string_view s);

    struct JoystickConfig {
        bool enabled;
        bool swap_axis;
        short walk_deadzone;
        short cursor_deadzone;
        JoystickButton buttons[32];
        JoystickButton buttons_mod[32];

    };

    struct AudioInfo {
        int freq;
    };

    void init_video(const VideoConfig &config, const char *title);

    void set_window_icon(const void *icon_data, size_t icon_size);

    void configure_controller(const JoystickConfig &cfg);

    void close_video();

    AudioInfo init_audio(const AudioConfig &config, SDL_AudioCallback cb, void *cb_ctx);
    void pause_audio(bool pause);
    void close_audio();


    void present_rect(uint16_t *pixels, unsigned int pitch, unsigned int x, unsigned int y, unsigned int xs,unsigned ys);
    void swap_render_buffers();
    void swap_display_buffers();
    void show_blend_transition(const SDL_Rect &wrkarea, const SDL_Rect &prev, const SDL_Rect &next, float phase);
    void show_slide_transition(const SDL_Rect &visible_from, const SDL_Rect &visible_where,
                               const SDL_Rect &hidden_from, const SDL_Rect &hidden_where);

    void set_quit_callback(std::function<void()> fn);
    MS_EVENT getMsEvent()  {
        std::lock_guard _(_mx);
        MS_EVENT out = ms_event;
        ms_event.event = 0;
        ms_event.event_type = 0;
        return out;
    }

    bool get_shift_key_state() const {
        return _key_shift;
    }
    bool get_control_key_state() const {
        return _key_control;
    }
    bool get_capslock_state() const {
        return _key_capslock;
    }

    bool is_keyboard_ready() const;
    std::uint16_t pop_keyboard_code() ;

    bool is_quit_requested() const {
        return _quit_requested;
    }
    void cancel_quit_request() {
        _quit_requested = false;
    }

    void show_mouse_cursor(const unsigned short *ms_hi_format, SDL_Point finger);
    void hide_mouse_cursor();

    void load_sprite(int sprite_id, const unsigned short *hi_image);
    void place_sprite(int sprite_id, int x, int y);
    void scale_sprite(int sprite_id, int x, int y, int w, int h);
    void hide_sprite(int sprite_id);
    void sprite_set_zindex(int sprite_id, int zindex);
    void unload_sprite(int sprite);
    void enable_crt_filter(bool enable);
    bool is_crt_enabled() const;


    bool is_joystick_used() const;
    bool is_joystick_enabled() const;
protected:

    struct SDL_Deleter {
        void operator()(SDL_Window *);
        void operator()(SDL_Renderer *);
        void operator()(SDL_Surface *);
        void operator()(SDL_Texture *);
    };

    struct BlendTransitionReq {
        SDL_Rect wrkarea;
        SDL_Rect prev;
        SDL_Rect next;
        float phase;
    };

    struct SlideTransitionReq {
        SDL_Rect visible_from;
        SDL_Rect visible_where;
        SDL_Rect hidden_from;
        SDL_Rect hidden_where;

    };

    enum class DisplayRequest {
        update,
        swap_render_buffers,
        swap_visible_buffers,
        blend_transition,
        slide_transition,
        show_mouse_cursor,  //< loads mouse cursor and shows it
        hide_mouse_cursor,   //< clears mouse cursor

        sprite_load,
        sprite_unload,
        sprite_place,
        sprite_scale,
        sprite_zindex,
        sprite_hide
    };

    struct SDL_Audio_Deleter {
        void operator()(SDL_AudioDeviceID x);
    };

    struct Sprite {
        int id = {};
        int zindex = {};
        std::unique_ptr<SDL_Texture, SDL_Deleter> _txtr = {};
        SDL_Rect _rect = {};
        bool shown = false;
    };

    using SpriteList = std::vector<Sprite>;


    MS_EVENT ms_event;
    mutable std::mutex _mx;
    int aspect_x = 4;
    int aspect_y = 3;
    CrtFilterType _crt_filter= CrtFilterType::autoselect;
    bool _enable_crt = true;
    std::function<void()> _quit_callback;
    JoystickConfig _jcontrol_map;
    bool _jcontrol_mod_key = false;
    bool _jcontrol_used = false;

    std::unique_ptr<SDL_Window, SDL_Deleter> _window;
    std::unique_ptr<SDL_Renderer, SDL_Deleter> _renderer;
    std::unique_ptr<SDL_Texture, SDL_Deleter> _texture;
    std::unique_ptr<SDL_Texture, SDL_Deleter> _texture2;
    std::unique_ptr<SDL_Texture, SDL_Deleter> _crt_effect;
    std::unique_ptr<SDL_Texture, SDL_Deleter> _mouse;
    unique_value<SDL_AudioDeviceID, SDL_Audio_Deleter> _audio;
    SDL_Texture *_visible_texture;
    SDL_Texture *_hidden_texture;

    std::jthread _render_thread;

    bool _fullscreen_mode = false;
    bool _present = false;    
    std::atomic<bool> _key_control = false;
    std::atomic<bool> _key_shift = false;
    std::atomic<bool> _key_capslock = false;
    std::atomic<bool> _quit_requested = false;



    std::vector<char> _display_update_queue;
    using QueueIter = const char *;
    std::queue<uint16_t> _keyboard_queue;
    SDL_Rect _mouse_rect;
    SDL_Point _mouse_finger;
    SpriteList _sprites;


    int axis1_cooldown = -1;
    int axis2_cooldown = -1;
    int check_axis_dir(int &cooldown, int value);

    Uint32 _update_request_event;
    Uint32 _refresh_request;


    void event_loop(std::stop_token stp);
    void update_screen(bool force_refresh = false);


    template<typename T>
    requires(std::is_trivially_copy_constructible_v<T>)
    void push_item(const T &item);
    void push_item(const std::string_view &item);
    void push_update_msg(const SDL_Rect &rc, const uint16_t *data, int pitch);
    void push_swap_buffers();

    template<typename T>
    requires(std::is_trivially_copy_constructible_v<T>)
    void pop_item(QueueIter &iter, T &item);
    std::string_view pop_data(QueueIter &iter, std::size_t size);

    SDL_Rect get_window_aspect_rect() const;
    static SDL_Rect to_window_rect(const SDL_Rect &winrc, const SDL_Rect &source_rect) ;
    static SDL_Point to_window_point(const SDL_Rect &win_rec, const SDL_Point &pt) ;
    static SDL_Point to_source_point(const SDL_Rect &win_rec, const SDL_Point &win_pt) ;
    static SDL_Rect transition_rect(const SDL_Rect &beg, const SDL_Rect &end, float phase);
    static int transition_int(int beg, int end, float phase);
    void generateCRTTexture(SDL_Renderer* renderer, SDL_Texture** texture, int width, int height, CrtFilterType type);
    void signal_push();


    void refresh_screen();
    std::optional<BlendTransitionReq> blend_transition;
    std::optional<SlideTransitionReq> slide_transition;

    void push_hi_image(const unsigned short *image);
    void update_zindex();

    void joystick_handle();
    void generate_j_event(int button, char up);
    static int adjust_deadzone(int v, short deadzone);

};