How to make a shortcode that will display a link to a specific folder?

function amur_gallery_func( $atts ) {
    if( function_exists('eazyest_gallery') ){
        $global_post = $GLOBALS['post'];
        global $post;
        global $wp_query;
        $atts = shortcode_atts( array( 'id' => 0 ), $atts );
        $args = array(
            'post_type'      => eazyest_gallery()->post_type,
            'p'              => $atts['id'],
            'posts_per_page' => 1
        );
        $query = new WP_Query( $args );
        if ( $query->have_posts()) {
            $query->the_post();
            if (get_the_ID() == $atts['id'])
                $out = "<a href=\"".get_the_permalink()."\" title=\"".esc_attr( sprintf( __( 'View folder “%s”', 'eazyest-gallery' ), the_title_attribute( 'echo=0' ) ) )."\" rel=\"bookmark\">".eazyest_frontend()->folder_thumbnail_html( $post_id )."</a>";
        }
        wp_reset_query();
        wp_reset_postdata();
        $GLOBALS['post'] = $global_post;
        return $out;
    }
    return "";
}
add_shortcode( 'amur_gallery', 'amur_gallery_func' );