You can just use wp_get_nav_menu_items( $menu, $args );
to get list of menu items created in appearance.
You can print result the way you want. Before printing just make sure the datas are not empty and so. I didn’t add any validation. So use according to your need.
For example:
We’ll try to print the data at wp_head
add_action('wp_head','menu_to_js');
function menu_to_js(){
$locations = get_nav_menu_locations();
$menu = wp_get_nav_menu_object( $locations[ $menu_name ] );//$menu_name should be your menu name
$menu_items = wp_get_nav_menu_items($menu->term_id);
$menu_items = json_encode($menu_items);
//So now we have json encoded $menu_items, put that in javascript
?>
<script>
var menu_itemss = "<?php echo $menu_items; ?>";
//now manipulate in js and use the way you want.
</script>
<?php
}