Page links to media JS snippet

I use this little javascript snippets to add a button to the media manager in WP 3.6.1

This button copies the link of the first selected media (the blue one) into Page Links To input text.

jQuery(document).ready(function() {
    if(wp.media && wp.media.controller && wp.media.view)
    {
        var wpMediaFramePost = wp.media.view.MediaFrame.Post;
        wp.media.view.MediaFrame.Post = wpMediaFramePost.extend(
        {
            mainInsertToolbar: function(view)
            {
                'use strict';

                wpMediaFramePost.prototype.mainInsertToolbar.call(this, view);

                var controller = this;

                this.selectionStatusToolbar(view);

                view.set('pageLinksTo', {
                    style: 'primary',
                    priority: 80,
                    text: 'Link page to the media',
                    requires: { selection: true },

                    click: function()
                    {
                        var state = controller.state();
                        var selection = state.get('selection')._byId;
                        var imagePath;

                        _.each(selection, function(item)
                        {
                            imagePath = item.attributes.sizes.full.url;
                            return;
                        });

                        if(imagePath && jQuery('#cws-links-to-choose-custom').exists())
                        {
                            controller.close();

                            jQuery('#cws-links-to-choose-custom').click();
                            jQuery('#cws-links-to').val(imagePath);
                            jQuery('#cws-links-to').focus();
                        }
                    }
                });
            }
        });
    }
}

This snippet was inspired by the following post https://wordpress.stackexchange.com/questions/78881/wordpress-3-5-media-manager-add-a-button

https://www.ads-software.com/plugins/page-links-to/