gistfile1.txt

<?php namespace Processwire;
$menuModule = $modules->get('MarkupMenuBuilder');

$lang_name = user("language")->name;

$menu_page = pages()->get(2092);

if($lang_name == "english") {
	$menu_page = pages()->get(2095);
} elseif ($lang_name == "russian") {
$menu_page = pages()->get(2091);
}

$menu = $menuModule->getMenuItems($menu_page, 1, [
	"current_class_level" => 3
]);

$mainmenu = buildMainMenu(0, $menu, 0, "mainmenu", "mainmenuList");
?>

<nav class="mainmenu">
	<div class="mainmenu__inner">
		<?= $mainmenu; ?>
	</div>
</nav>

gistfile2.txt

/**
* Builds a nested list (menu items) of a single menu from an Array of menu items.
*
* A recursive function to display nested list of menu items.
*
* @access private
* @param Int $parent ID of menu item.
* @param Array $menu Array of menu items to display.
* @param Int $first Helper variable to designate first menu item.
* @return string $out.
*
*/
function buildMainMenu($parent = 0, $menu, $first = 0, $class, $menuId) {
	$out = '';
	$has_child = false;
	foreach ($menu as $id => $m) {

		$parentID = isset($m['parent_id']) ? $m['parent_id'] : 0;
		$newtab = isset($m['newtab']) && $m['newtab'] ? " target='_blank'" : '';

		if (isset($m["pages_id"])) {
			if($m["pages_id"] === 2026) {
				if (page()->matches("has_parent=2026")) {
					$m['is_current'] = 1;
				}
			}
		}

		if (isset($m["pages_id"])) {
			if($m["pages_id"] === 1765) {
				if (page()->matches("has_parent=1765")) {
					$m['is_current'] = 1;
				}
			}
		}

		// if this menu item is a parent; create the sub-items/child-menu-items
		if ($parentID == $parent) {// if this menu item is a parent; create the inner-items/child-menu-items

			// if this is the first child
			if ($has_child === false) {
				$has_child = true;// This is a parent
				if ($first == 0){
					$out .= "<ul id='{$menuId}' class='{$class}__list'>\n";
					$first = 1;
				}
				else $out .= "\n<ul class='{$class}__sublist'>\n";
			}

			$isParentItemClass = isset($m['is_parent']) && $m['is_parent'] ? " is-dropdown-submenu-parent" : "";
			$isActiveItemClass = isset($m['is_current']) && $m['is_current'] ? " is-current" : "";
			$isFirstItemClass = isset($m['is_first']) && $m['is_first'] ? " {$class}__item--first" : "";
			$isLastItemClass = isset($m['is_last']) && $m['is_last'] ? " {$class}__item--last" : "";
			$isActiveLinkClass = isset($m['is_current']) && $m['is_current'] ? " is-current" : "";
			$subMenuClass = isset($m['parent_id']) ? " {$class}__subitem" : " {$class}__item";
			$subMenuLinkClass = isset($m['parent_id']) ? " {$class}__subitem-link" : " {$class}__item-link";

			// a menu item
			$out .= "<li class='" . $isActiveItemClass . $isFirstItemClass . $isLastItemClass . $subMenuClass . $isParentItemClass . "'><a class='". $isActiveLinkClass . $subMenuLinkClass ."' href='" . $m["url"] . "'" . $newtab . "><span>" . $m["title"];
			// if menu item has children
			if (isset($m['is_parent']) && $m['is_parent']) {
				$out .= '</span></a>';
			}

			else $out .= '</span></a>';

			// call function again to generate nested list for sub-menu items belonging to this menu item.
			$out .= buildMainMenu($id, $menu, $first, $class, $menuId);
			$out .= "</li>\n";

		}// end if parent

	}// end foreach

	if ($has_child === true) $out .= "</ul>\n";

	return $out;

}