src/reducers/menus.js

const OPEN_MENU = 'scratch-gui/menus/OPEN_MENU';
const CLOSE_MENU = 'scratch-gui/menus/CLOSE_MENU';

const MENU_ABOUT = 'aboutMenu';
const MENU_ACCOUNT = 'accountMenu';
const MENU_EDIT = 'editMenu';
const MENU_FILE = 'fileMenu';
const MENU_LANGUAGE = 'languageMenu';
const MENU_LOGIN = 'loginMenu';
const MENU_MODE = 'modeMenu';
const MENU_SETTINGS = 'settingsMenu';
const MENU_ACCENT = 'accentMenu';
const MENU_BLOCKS_THEME = 'blocksThemeMenu';
const MENU_GUI = 'guiMenu';
const MENU_MENUBAR_ALIGN = 'menubarAlignMenu';
const MENU_WALLPAPER = 'wallpaperMenu';
const MENU_FONTS = 'fontsMenu';
const MENU_ERRORS = 'errorsMenu';

class Menu {
    constructor (id) {
        this.id = id;
        this.children = [];
        this.parent = null;
    }

    addChild (menu) {
        this.children.push(menu);
        menu.parent = this;
        return this;
    }

    descendants () {
        return this.children.flatMap(child => [child, ...child.descendants()]);
    }

    siblings () {
        if (!this.parent) return [];

        return this.parent.children.filter(child => child.id !== this.id);
    }

    findById (id) {
        if (this.id === id) return this;

        for (const child of this.children) {
            const found = child.findById(id);
            if (found) return found;
        }

        return null;
    }
}

// Structure of nested menus, used for collapsing submenus logic.
const rootMenu = new Menu('root')
    .addChild(new Menu(MENU_ERRORS))
    .addChild(
        new Menu(MENU_SETTINGS)
            .addChild(new Menu(MENU_LANGUAGE))
            .addChild(new Menu(MENU_ACCENT))
            .addChild(new Menu(MENU_GUI))
            .addChild(new Menu(MENU_MENUBAR_ALIGN))
            .addChild(new Menu(MENU_WALLPAPER))
            .addChild(new Menu(MENU_FONTS))
            .addChild(new Menu(MENU_BLOCKS_THEME))
    )
    .addChild(new Menu(MENU_FILE))
    .addChild(new Menu(MENU_EDIT))
    .addChild(new Menu(MENU_MODE))
    .addChild(new Menu(MENU_SETTINGS))
    .addChild(new Menu(MENU_LOGIN))
    .addChild(new Menu(MENU_ACCOUNT))
    .addChild(new Menu(MENU_ABOUT));

const initialState = {
    [MENU_ABOUT]: false,
    [MENU_ACCOUNT]: false,
    [MENU_EDIT]: false,
    [MENU_FILE]: false,
    [MENU_LANGUAGE]: false,
    [MENU_LOGIN]: false,
    [MENU_MODE]: false,
    [MENU_SETTINGS]: false,
    [MENU_ACCENT]: false,
    [MENU_GUI]: false,
    [MENU_MENUBAR_ALIGN]: false,
    [MENU_WALLPAPER]: false,
    [MENU_FONTS]: false,
    [MENU_BLOCKS_THEME]: false,
    [MENU_ERRORS]: false
};

const reducer = function (state, action) {
    if (typeof state === 'undefined') state = initialState;
    switch (action.type) {
    case OPEN_MENU: {
        const menu = rootMenu.findById(action.menu);
        // Close siblings when opening a menu
        const toClose = menu.siblings().flatMap(sibling => [sibling, ...sibling.descendants()]);

        return {
            ...state,
            [action.menu]: true,
            ...Object.fromEntries(toClose.map(({id}) => [id, false]))
        };
    }
    case CLOSE_MENU: {
        const menu = rootMenu.findById(action.menu);
        // Close this menu and any submenus
        const toClose = [menu, ...menu.descendants()];

        return {
            ...state,
            ...Object.fromEntries(toClose.map(({id}) => [id, false]))
        };
    }
    default:
        return state;
    }
};
const openMenu = menu => ({
    type: OPEN_MENU,
    menu: menu
});
const closeMenu = menu => ({
    type: CLOSE_MENU,
    menu: menu
});

const openAboutMenu = () => openMenu(MENU_ABOUT);
const closeAboutMenu = () => closeMenu(MENU_ABOUT);
const aboutMenuOpen = state => state.scratchGui.menus[MENU_ABOUT];

const openAccountMenu = () => openMenu(MENU_ACCOUNT);
const closeAccountMenu = () => closeMenu(MENU_ACCOUNT);
const accountMenuOpen = state => state.scratchGui.menus[MENU_ACCOUNT];

const openEditMenu = () => openMenu(MENU_EDIT);
const closeEditMenu = () => closeMenu(MENU_EDIT);
const editMenuOpen = state => state.scratchGui.menus[MENU_EDIT];

const openFileMenu = () => openMenu(MENU_FILE);
const closeFileMenu = () => closeMenu(MENU_FILE);
const fileMenuOpen = state => state.scratchGui.menus[MENU_FILE];

const openLanguageMenu = () => openMenu(MENU_LANGUAGE);
const closeLanguageMenu = () => closeMenu(MENU_LANGUAGE);
const languageMenuOpen = state => state.scratchGui.menus[MENU_LANGUAGE];

const openLoginMenu = () => openMenu(MENU_LOGIN);
const closeLoginMenu = () => closeMenu(MENU_LOGIN);
const loginMenuOpen = state => state.scratchGui.menus[MENU_LOGIN];

const openModeMenu = () => openMenu(MENU_MODE);
const closeModeMenu = () => closeMenu(MENU_MODE);
const modeMenuOpen = state => state.scratchGui.menus[MENU_MODE];

const openSettingsMenu = () => openMenu(MENU_SETTINGS);
const closeSettingsMenu = () => closeMenu(MENU_SETTINGS);
const settingsMenuOpen = state => state.scratchGui.menus[MENU_SETTINGS];

const openAccentMenu = () => openMenu(MENU_ACCENT);
const closeAccentMenu = () => closeMenu(MENU_ACCENT);
const accentMenuOpen = state => state.scratchGui.menus[MENU_ACCENT];

const openGuiMenu = () => openMenu(MENU_GUI);
const closeGuiMenu = () => closeMenu(MENU_GUI);
const guiMenuOpen = state => state.scratchGui.menus[MENU_GUI];

const openMenubarAlignMenu = () => openMenu(MENU_MENUBAR_ALIGN);
const closeMenubarAlignMenu = () => closeMenu(MENU_MENUBAR_ALIGN);
const menubarAlignMenuOpen = state => state.scratchGui.menus[MENU_MENUBAR_ALIGN];

const openBlocksThemeMenu = () => openMenu(MENU_BLOCKS_THEME);
const closeBlocksThemeMenu = () => closeMenu(MENU_BLOCKS_THEME);
const blocksThemeMenuOpen = state => state.scratchGui.menus[MENU_BLOCKS_THEME];

const openWallpaperMenu = () => openMenu(MENU_WALLPAPER);
const closeWallpaperMenu = () => closeMenu(MENU_WALLPAPER);
const wallpaperMenuOpen = state => state.scratchGui.menus[MENU_WALLPAPER];

const openFontsMenu = () => openMenu(MENU_FONTS);
const closeFontsMenu = () => closeMenu(MENU_FONTS);
const fontsMenuOpen = state => state.scratchGui.menus[MENU_FONTS];

const openErrorsMenu = () => openMenu(MENU_ERRORS);
const closeErrorsMenu = () => closeMenu(MENU_ERRORS);
const errorsMenuOpen = state => state.scratchGui.menus[MENU_ERRORS];

export {
    reducer as default,
    initialState as menuInitialState,
    openAboutMenu,
    closeAboutMenu,
    aboutMenuOpen,
    openAccountMenu,
    closeAccountMenu,
    accountMenuOpen,
    openEditMenu,
    closeEditMenu,
    editMenuOpen,
    openFileMenu,
    closeFileMenu,
    fileMenuOpen,
    openLanguageMenu,
    closeLanguageMenu,
    languageMenuOpen,
    openLoginMenu,
    closeLoginMenu,
    loginMenuOpen,
    openModeMenu,
    closeModeMenu,
    modeMenuOpen,
    openSettingsMenu,
    closeSettingsMenu,
    settingsMenuOpen,
    openAccentMenu,
    closeAccentMenu,
    accentMenuOpen,
    openGuiMenu,
    closeGuiMenu,
    guiMenuOpen,
    openMenubarAlignMenu,
    closeMenubarAlignMenu,
    menubarAlignMenuOpen,
    openBlocksThemeMenu,
    closeBlocksThemeMenu,
    blocksThemeMenuOpen,
    openWallpaperMenu,
    closeWallpaperMenu,
    wallpaperMenuOpen,
    openFontsMenu,
    closeFontsMenu,
    fontsMenuOpen,
    openErrorsMenu,
    closeErrorsMenu,
    errorsMenuOpen
};