nesemu/gui/components/window_menu.c

//
// Created by william on 8/23/24.
//

#include <SDL_ttf.h>
#include <assert.h>
#include "window_menu.h"
#include "../../include/types.h"
#include "log.h"

/**
 * Easy declaration of commonly used item loop. The current item is in the 'item' variable.
 * Put the loop's body between FOR_EACH_ITEM and END_FOR_EACH_ITEM.
 */
#define FOR_EACH_ITEM_(list)\
    MenuItemComponent *item;          \
    LinkedListCursor cursor = menu_create_item_cursor(&(list), &item); \
    while (item != NULL) {

#define FOR_EACH_ITEM(menu) FOR_EACH_ITEM_((menu)->items)
#define FOR_EACH_SUBITEM(menu_item) FOR_EACH_ITEM_((menu_item)->sub_items)

#define END_FOR_EACH_ITEM \
    item = menu_get_next_item(&cursor); \
    }

#define CREATE_PIXEL_TEXTURE(texture, menu, color)                                                                   \
    pixel texture ## _buffer[1] = {color};                                                                           \
    (menu)->texture = SDL_CreateTexture((menu)->renderer, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STATIC, 1, 1); \
    SDL_UpdateTexture((menu)->texture, NULL, &texture ## _buffer, sizeof(pixel))

static inline LinkedListCursor menu_create_item_cursor(LinkedList *list, MenuItemComponent **first_component) {
    LinkedListCursor cursor = linked_list_cursor_create(list);
    if (cursor.current != NULL) {
        *first_component = cursor.current->data;
    } else {
        *first_component = NULL;
    }

    return cursor;
}

static inline MenuItemComponent *menu_get_next_item(LinkedListCursor *cursor) {
    if (!linked_list_cursor_has_next(cursor)) {
        return NULL;
    }

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

MenuComponent *menu_create(Window *window, TTF_Font *font) {
    MenuComponent *menu = malloc(sizeof(MenuComponent));

    menu->window_width = window->width * window->scale;
    menu->visible = false;

    menu->items = linked_list_create(false);
    menu->highlight_item = NULL;

    menu->renderer = window->sdl_context.renderer;
    menu->font = font;
    CREATE_PIXEL_TEXTURE(background_texture, menu, MENU_BACKGROUND_COLOR);
    CREATE_PIXEL_TEXTURE(highlight_texture, menu, MENU_HIGHLIGHT_COLOR);

    return menu;
}

MenuItemComponent *menu_item_create(char *label, on_click_callback on_click) {
    MenuItemComponent *menu_item = malloc(sizeof(MenuItemComponent));

    menu_item->label = label;
    menu_item->on_click = on_click;
    menu_item->sub_items = linked_list_create(false);
    menu_item->is_highlighted = false;

    return menu_item;
}

void menu_append(MenuComponent *menu, MenuItemComponent *menu_item) {
    LinkedList *menu_items = &menu->items;
    linked_list_add(menu_items, menu_item);
}

void menu_item_append(MenuItemComponent *menu_item, MenuItemComponent *sub_item) {
    LinkedList *sub_items = &menu_item->sub_items;
    linked_list_add(sub_items, sub_item);
}

void menu_item_build(MenuItemComponent *menu_item, SDL_Renderer *renderer, TTF_Font *font, bool top_level) {
    SDL_Color label_color = MENU_TEXT_COLOR;
    int base_x = menu_item->collision_rect.x;
    int base_y = MENU_HEIGHT + MENU_ITEM_MARGIN_Y;

    if (!top_level) {
        base_x += menu_item->collision_rect.w;
        base_y = menu_item->collision_rect.y + MENU_ITEM_MARGIN_Y;
    }

    FOR_EACH_SUBITEM(menu_item)
        SDL_Surface *label_surface = TTF_RenderText_Solid(font, item->label, label_color);

        item->label_texture = SDL_CreateTextureFromSurface(renderer, label_surface);
        SDL_Rect draw_rect = {base_x + MENU_ITEM_MARGIN_X, base_y, label_surface->w, label_surface->h};
        item->draw_rect = draw_rect;

        SDL_Rect menu_item_col = {base_x, base_y - MENU_ITEM_MARGIN_Y, label_surface->w + MENU_ITEM_MARGIN_X * 2,
                                  MENU_HEIGHT};
        item->collision_rect = menu_item_col;
        base_y += item->draw_rect.h + MENU_ITEM_MARGIN_Y * 2;

        SDL_FreeSurface(label_surface);

        menu_item_build(item, renderer, font, false);
    END_FOR_EACH_ITEM
}

void menu_build(MenuComponent *menu) {
    assert(menu->font != NULL);

    SDL_Color label_color = MENU_TEXT_COLOR;
    int next_x = MENU_ITEM_MARGIN_X;
    FOR_EACH_ITEM(menu)
        SDL_Surface *label_surface = TTF_RenderText_Solid(menu->font, item->label, label_color);

        item->label_texture = SDL_CreateTextureFromSurface(menu->renderer, label_surface);
        SDL_Rect draw_rect = {next_x, MENU_ITEM_MARGIN_Y, label_surface->w, label_surface->h};
        item->draw_rect = draw_rect;

        SDL_Rect menu_item_col = {next_x - MENU_ITEM_MARGIN_X, 0, label_surface->w + MENU_ITEM_MARGIN_X * 2,
                                  MENU_HEIGHT};
        item->collision_rect = menu_item_col;
        next_x += item->draw_rect.w + MENU_ITEM_MARGIN_X * 2;

        SDL_FreeSurface(label_surface);

        menu_item_build(item, menu->renderer, menu->font, true);
    END_FOR_EACH_ITEM
}

void menu_item_render(MenuComponent *menu, MenuItemComponent *menu_item) {
    SDL_Texture *back_texture = menu_item->is_highlighted ? menu->highlight_texture : menu->background_texture;
    SDL_RenderCopy(menu->renderer, back_texture, NULL, &menu_item->collision_rect);
    SDL_RenderCopy(menu->renderer, menu_item->label_texture, NULL, &menu_item->draw_rect);

    if (!menu_item->is_highlighted) {
        return;
    }

    FOR_EACH_SUBITEM(menu_item)
        menu_item_render(menu, item);
    END_FOR_EACH_ITEM
}

void menu_render(MenuComponent *menu) {
    if (!menu->visible) {
        return;
    }

    int display_width = menu->window_width;
    int display_height = MENU_HEIGHT;
    SDL_Rect menu_rect = {0, 0, display_width, display_height};
    SDL_RenderCopy(menu->renderer, menu->background_texture, NULL, &menu_rect);

    FOR_EACH_ITEM(menu)
        menu_item_render(menu, item);
    END_FOR_EACH_ITEM
}

void menu_item_list_destroy(LinkedList *list) {
    MenuItemComponent *menu_item;
    LinkedListCursor cursor = menu_create_item_cursor(list, &menu_item);
    while (menu_item != NULL) {
        menu_item_destroy(menu_item);

        menu_item = menu_get_next_item(&cursor);
    }

    linked_list_destroy(list);
}

void menu_destroy(MenuComponent *menu) {
    menu_item_list_destroy(&menu->items);

    SDL_DestroyTexture(menu->background_texture);
    free(menu);
}

void menu_item_destroy(MenuItemComponent *menu_item) {
    SDL_DestroyTexture(menu_item->label_texture);

    menu_item_list_destroy(&menu_item->sub_items);
    free(menu_item);
}

/**
 * Checks if a point is over a menu item.
 * This function will return true if the point is in an item or one of its sub-items.
 */
void menu_item_hover(MenuComponent *menu, MenuItemComponent *menu_item, SDL_Point *pos) {
    if (SDL_PointInRect(pos, &menu_item->collision_rect)) {
        menu_item->is_highlighted = true;
        menu->highlight_item = menu_item;
    } else if (menu_item->is_highlighted) { // We can't hover a sub-item if this item is not highlighted because it is not visible
        bool any_sub_highlighted = false;
        FOR_EACH_SUBITEM(menu_item)
            menu_item_hover(menu, item, pos);

            if (item->is_highlighted) {
                any_sub_highlighted = true;
            }
        END_FOR_EACH_ITEM

        // If any sub-item is highlighted, the current item also is
        menu_item->is_highlighted = any_sub_highlighted;
    }
}

bool menu_mouse_motion(MenuComponent *menu, int x, int y) {
    menu->visible = y <= MENU_VISIBLE_HEIGHT;
    SDL_Point pos = {x, y};

    menu->highlight_item = NULL;

    FOR_EACH_ITEM(menu)
        menu_item_hover(menu, item, &pos);
    END_FOR_EACH_ITEM

    return menu->highlight_item != NULL;
}

bool menu_mouse_click(MenuComponent *menu) {
    if (menu->highlight_item == NULL) {
        return false;
    }

    log_info("%s", menu->highlight_item->label);
    return true;
}

Component *menu_as_component(MenuComponent *menu) {
    Component *component = malloc(sizeof(Component));

    component->ref = menu;
    component->render = (void (*)(void *)) &menu_render;
    component->destroy = (void (*)(void *)) &menu_destroy;
    component->mouse_motion = (bool (*)(void *, int, int)) &menu_mouse_motion;
    component->mouse_click = (bool (*)(void *)) &menu_mouse_click;

    return component;
}