get_the_section_a_z_widget( array $args, array $instance )

function get_the_section_a_z_widget( array $args, array $instance ): string { //phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedFunctionFound
	do_action( 'a_z_listing_log', 'A-Z Listing: Running widget' );

	$instance = wp_parse_args(
		$instance,
		array(
			'all_children'     => 'true',
			'exclude_terms'    => '',
			'hide_empty_terms' => false,
			'parent_post'      => '',
			'parent_term'      => '',
			'post'             => -1, // target.
			'page'             => -1, // obsolete target.
			'post_type'        => 'page',
			'taxonomy'         => '',
			'terms'            => '',
			'title'            => '',
			'type'             => 'posts',
		)
	);

	$title      = esc_html( $instance['title'] );
	$target_url = '';
	if ( 0 < $instance['post'] || 0 < $instance['page'] ) { // target.
		$target_id = (int) $instance['post']; // target.
		if ( ! ( 0 < $instance['post'] ) ) {
			$target_id = (int) $instance['page']; // obsolete target.
		}

		$target_url = get_the_permalink( $target_id );
		if ( empty( $title ) ) {
			$title = get_the_title( $target_id );
		}
	} elseif ( empty( $title ) ) {
		$title = esc_html__( 'A-Z Listing', 'a-z-listing' );
	}

	$hide_empty_terms = true === $instance['hide_empty_terms'] ? 'true' : 'false';

	$ret  = '';
	$ret .= $args['before_widget'];

	$ret .= $args['before_title'];
	$ret .= $title;
	$ret .= $args['after_title'];

	$ret .= do_shortcode(
		"[a-z-listing
            alphabet=''
            display='{$instance['type']}'
            exclude-posts=''
            exclude-terms='{$instance['exclude_terms']}'
            get-all-children='{$instance['all_children']}'
            group-numbers=''
            grouping=''
            hide-empty-terms='{$hide_empty_terms}'
            numbers='hide'
            parent-post='{$instance['parent_post']}'
            parent-term='{$instance['parent_term']}'
            post-type='{$instance['post_type']}'
            return='letters'
            target='{$target_url}'
            taxonomy='{$instance['taxonomy']}'
            terms='{$instance['terms']}'
        ]"
	);

	$ret .= $args['after_widget'];

	return $ret;
}