/**
 * @ORMEntity(repositoryClass="AppRepositoryMenuRepository")
 */
class Menu
{
    /**
     * @Groups({"menu"})
     * @ORMId
     * @ORMColumn(type="integer")
     * @ORMGeneratedValue(strategy="AUTO")
     */
    private $id;

    // ...

    /**
     * References translated menus.
     * @Groups({"localized_menus"})
     *
     * @ORMOneToMany(
     *     targetEntity="LocalizedMenu"
     *     ,mappedBy="parentMenu"
     *     ,indexBy="locale"
     *     ,cascade={"persist", "remove"}
     * )
     * @ORMOrderBy({"locale" = "ASC"})
     */
    private $localizedMenus;

    // ...

    public function getLocalizedMenu($locale) {
        if (!isset($this->localizedMenus[$locale])) {
            return new LocalizedMenu($locale, $this);
        }
        return $this->localizedMenus[$locale];
    }

    public function addLocalizedMenu($localizedMenu): self
    {
        $this->localizedMenus[$localizedMenu->getLocale()] = $localizedMenu;

        return $this;
    }
}

/**
 * @ORMEntity(repositoryClass="AppRepositoryLocalizedMenuRepository")
 */
class LocalizedMenu
{
    public function __construct($locale, $menu) {
        $this->locale = $locale;
        $this->parentMenu = $menu;
        $this->parentMenu->addLocalizedMenu($this);
    }

    // region FIELDS
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @ORMId
     * @ORMColumn(type="integer")
     * @ORMGeneratedValue(strategy="AUTO")
     */
    private $id;
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @var $locale string
     * @ORMColumn(
     *     type                 = "string"
     *     ,unique              = true
     * )
     */
    private $locale = "";
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @ORMColumn(
     *     type                 = "string",
     *     length               = 75
     * )
     */
    private $title = "";
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @var $description string Extra description for this menu item
     * @ORMColumn(
     *     type                 = "text",
     *     name                 = "description"
     * )
     */
    private $description = "";
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @ORMColumn(
     *     type                 = "datetime",
     *     name                 = "creation_date"
     * )
     * @AssertDateTime()
     */
    private $creationDate;
    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @ORMColumn(
     *     type                 = "datetime",
     *     name                 = "edit_date"
     * )
     * @AssertDateTime()
     */
    private $editDate;

    /**
     * @Groups({"localized_menu", "localized_menus"})
     * @ORMColumn(type="text")
     * @AssertNotBlank(
     *     message = "Een menu item is een pagina die inhoud nodig heeft, vergeet dit niet"
     * )
     */
    private $content = "";

    /**
     * @var $parentMenu Menu Parent menu for this localized menu
     *
     * @Groups({"localized_menu", "localized_parent_menu"})
     * @ORMManyToOne(
     *     targetEntity="Menu",
     *     inversedBy="localizedMenus"
     * )
     */
    private $parentMenu;
}

$builder
        ->add('localizedMenus', CollectionType::class, array(
            'entry_type' => LocalizedMenuType::class,
            "entry_options" => [
                "choice_locale" => $options["choice_locale"]
            ],
            'allow_add' => true,
            'allow_delete' => true,
            'required' => false
        ))

$builder
        ->add('title', TextType::class, array(
            'label'             => 'Titel',
            'trim'              => true
        ))
        ->add('description', TextareaType::class, array(
            'label'             => 'Omschrijving',
            'trim'              => true
        ))
        ->add('content', TextareaType::class, array(
            'label'             => 'Inhoud',
            'trim'              => true,
            'attr'              => array('class' => 'tinymce'),
            'data'              => " "
        ))
        ->add('locale', LocaleType::class, array(
            "choice_translation_locale" => $options["choice_locale"]
        ))
    ;