Sidebar menu shortcode

functions.php

add_shortcode('sidebar-menu','fwp_simplesidenav');
function fwp_simplesidenav( $atts, $content = null) {
		global $post;
		$current_page = $post->ID;

		extract( shortcode_atts( array(
			'exclude'      => '',
			'exclude_children_of' => '',
			'exclude_tree' => '',
			'children_of'  => $current_page,
			'type' => 'list',
			'children' => 'true',
			'siblings' => 'false',
			'show_root_only' => 'false',
			'siblings_of' => $current_page,
			'depth' => '',
			'showtree' => 'false',
			'group' => 'false',
			'inline' => 'false',
			'dropdown_default' => 'Select',
		  ), $atts ) );

		// establish variables
		$output = '';
		//$include = '';
		$thedepth = 0;
		$excluded_children = '';
	   

		if ( $siblings == 'true' ) {
			$children_of = $post->post_parent;
		}

		if ( $group !== 'false' ) {
			$group = 'group';
		} else {
			$group = 'flat';
		}

		$exclude_list = $exclude;

		//convert list of excluded pages to array
		$excluded = explode(',', $exclude_list);

		// if on excluded page, do not show list at all
		// if ( in_array($post->ID,$excluded) ) return false;

		//get the current page's ancestors either from existing value or by executing function
		$post_ancestors = ( isset($post->ancestors) ) ? $post->ancestors : get_post_ancestors($post);

		//get the top page id
		$top_page = $post_ancestors ? end($post_ancestors) : $post->ID;

		if ( $showtree === 'true' ) {
			$children_of = $top_page;
		}

		// FOR DEFAULT LISTS, EXCLUDE PAGES NOT IN DIRECT HIERARCHY
		$ancestors_me = implode( ',', $post_ancestors ) . ',' . $post->ID;

		foreach ($post_ancestors as $anc_id) {
			//if ancestor excluded, and hide on excluded, leave
			if ( in_array($anc_id,$excluded) && $instance['hide_on_excluded'] ) return false;

			$pageset = get_pages(array( 'child_of' => $anc_id, 'parent' => $anc_id, 'exclude' => $ancestors_me ));
			foreach ($pageset as $page) {
				$excludeset = get_pages(array( 'child_of' => $page->ID, 'parent' => $page->ID ));
				foreach ($excludeset as $expage) { $exclude_list .= ',' . $expage->ID; }
			}
		}

		// IF SHORTCODE LISTS ANY PAGES WITH EXCLUDED CHILDREN
		if ($exclude_children_of !== '') {
			// convert exclude_children_of from string into array
			$excluded_parent_array = explode(',', $exclude_children_of);
			foreach ($excluded_parent_array as $excluded_parent) {

				// using helper function my_get_page_children get IDs of child pages to exclude for this parent ID
				$excluded_parent = $this->my_get_page_children($excluded_parent);

				foreach ($excluded_parent as $excludedpage) {
					// concatenate all the child ids into one list
					$excluded_children .= ', ' . $excludedpage;
				}

			}
			//echo $excluded_children;
		   // print_r($excluded_children);
			$excluded_children_array = explode(',', $excluded_children);
			$exclude_list_array = explode(',', $exclude_list);
			$excluded_list = array_merge($exclude_list_array, $excluded_children_array);
			$excluded_list = array_unique($excluded_list);
			$csv_excluded_list = implode(",", $excluded_list);
		} else {
			$csv_excluded_list = $exclude_list;
		}

	   $parent_link = get_permalink($children_of);
	   $parent_title = get_the_title($children_of);

		// the unordered list
		$the_list =  wp_list_pages(array( 'title_li' => '', 'echo' => 0, 'depth' => $thedepth, 'child_of' => $children_of, 'sort_column' => 'menu_order', 'sort_order' => 'ASC', 'exclude' => $csv_excluded_list, 'exclude_tree' => $exclude_tree, ));

	   if ($type === 'list' && $the_list) {
			$output = '<ul class="parent-sidebar-menu"><li><a href="' . $parent_link . '">' . $parent_title . '</a><ul class="child-sidebar-menu">' . $the_list . '</ul></li></ul>';
		}

		return $output;
	}