nesemu/gui/components/window.c

//
// Created by william on 17/05/24.
//

#include <SDL.h>
#include "window.h"
#include "log.h"
#include "component.h"

// A sequential window ID
static int next_window_id = 1;

/**
 * Easy declaration of commonly used component loop. The current component is in the 'component' variable.
 * Put the loop's body between FOR_EACH_COMPONENT and END_FOR_EACH_COMPONENT.
 */
#define FOR_EACH_COMPONENT(window) \
    Component *component;          \
    LinkedListCursor cursor = window_create_component_cursor(window, &component); \
    while (component != NULL) {

#define END_FOR_EACH_COMPONENT \
    component = get_next_component(&cursor); \
    }

static inline LinkedListCursor window_create_component_cursor(Window *window, Component **first_component) {
    LinkedListCursor cursor = linked_list_cursor_create(&window->components);
    if (cursor.current != NULL) {
        *first_component = cursor.current->data;
    } else {
        *first_component = NULL;
    }

    return cursor;
}

static inline Component *get_next_component(LinkedListCursor *cursor) {
    if (!linked_list_cursor_has_next(cursor)) {
        return NULL;
    }

    LinkedListNode *next_node = linked_list_cursor_next(cursor);
    return next_node->data;
}

Window window_create(char *title, int width, int height, int scale) {
    WindowSdlContext context;

    int renderer_flags = SDL_RENDERER_ACCELERATED;
    int window_flags = 0;

    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        log_error("Couldn't initialize SDL: %s", SDL_GetError());
        exit(-1);
    }

    int actual_width = width * scale;
    int actual_height = height * scale;
    context.window = SDL_CreateWindow(title, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, actual_width,
                                      actual_height, window_flags);
    if (!context.window) {
        log_error("Failed to open %d x %d SDL window: %s", actual_width, actual_height, SDL_GetError());
        exit(-1);
    }

    context.renderer = SDL_CreateRenderer(context.window, -1, renderer_flags);
    if (!context.renderer) {
        log_error("Failed to create renderer: %s", SDL_GetError());
        SDL_DestroyWindow(context.window);
        exit(-1);
    }

    Window window;
    window.id = next_window_id++;
    window.width = width;
    window.height = height;
    window.scale = scale;
    window.sdl_context = context;
    window.components = linked_list_create(false);

    return window;
}

SDL_Texture *window_create_texture(Window *window, int access) {
    SDL_Renderer *renderer = window->sdl_context.renderer;
    return SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888, access, window->width, window->height);
}

void window_add_component(Window *window, Component *component) {
    LinkedList *components = &window->components;
    linked_list_add(components, component);
}

void window_render_components(Window *window) {
    FOR_EACH_COMPONENT(window)
        component->render(component->ref);
    END_FOR_EACH_COMPONENT
}

void window_render_texture(Window *window, SDL_Texture *texture) {
    SDL_Renderer *renderer = window->sdl_context.renderer;
    SDL_RenderClear(renderer);
    SDL_RenderCopy(renderer, texture, NULL, NULL);
}

void window_present(Window *window) {
    SDL_RenderPresent(window->sdl_context.renderer);
}

void window_destroy(Window *window) {
    FOR_EACH_COMPONENT(window)
        component->destroy(component->ref);
        free(component);
    END_FOR_EACH_COMPONENT

    SDL_DestroyRenderer(window->sdl_context.renderer);
    SDL_DestroyWindow(window->sdl_context.window);
}

void window_mouse_motion(Window *window, int x, int y) {
    FOR_EACH_COMPONENT(window)
        bool matching = component->mouse_motion(component->ref, x, y);
        if (matching) {
            // If a component has matched, we don't pass the event to the next ones
            // This will prevent, for example, clicking on a UI element behind another one.
            break;
        }
    END_FOR_EACH_COMPONENT
}

void window_mouse_click(Window *window) {
    FOR_EACH_COMPONENT(window)
        bool matching = component->mouse_click(component->ref);
        if (matching) {
            break;
        }
    END_FOR_EACH_COMPONENT
}