<?php
namespace WPGraphQL\Data\Connection;

use Exception;
use GraphQLRelay\Relay;
use GraphQL\Type\Definition\ResolveInfo;
use WPGraphQL\AppContext;

/**
 * Class MenuItemConnectionResolver
 *
 * @package WPGraphQL\Data\Connection
 */
class MenuItemConnectionResolver extends PostObjectConnectionResolver {

	/**
	 * MenuItemConnectionResolver constructor.
	 *
	 * @param mixed       $source     source passed down from the resolve tree
	 * @param array       $args       array of arguments input in the field as part of the GraphQL query
	 * @param AppContext  $context    Object containing app context that gets passed down the resolve tree
	 * @param ResolveInfo $info       Info about fields passed down the resolve tree
	 *
	 * @throws Exception
	 */
	public function __construct( $source, array $args, AppContext $context, ResolveInfo $info ) {
		parent::__construct( $source, $args, $context, $info, 'nav_menu_item' );
	}

	/**
	 * Returns the query args for the connection to resolve with
	 *
	 * @return array
	 */
	public function get_query_args() {

		$menu_locations = get_theme_mod( 'nav_menu_locations' );

		$query_args = [
			'orderby' => 'menu_order',
			'order'   => 'ASC',
		];

		if ( isset( $this->args['where']['parentDatabaseId'] ) ) {
			$query_args['meta_key']   = '_menu_item_menu_item_parent';
			$query_args['meta_value'] = (int) $this->args['where']['parentDatabaseId'];
		}

		if ( isset( $this->args['where']['parentId'] ) ) {
			$id_parts = Relay::fromGlobalId( $this->args['where']['parentId'] );
			if ( isset( $id_parts['id'] ) ) {
				$query_args['meta_key']   = '_menu_item_menu_item_parent';
				$query_args['meta_value'] = (int) $id_parts['id'];
			}
		}

		// Get unique list of locations as the default limitation of
		// locations to allow public queries for.
		// Public queries should only be allowed to query for
		// Menu Items assigned to a Menu Location
		$locations = is_array( $menu_locations ) && ! empty( $menu_locations ) ? array_unique( array_values( $menu_locations ) ) : [];

		// If the location argument is set, set the argument to the input argument
		if ( isset( $this->args['where']['location'] ) && isset( $menu_locations[ $this->args['where']['location'] ] ) ) {

			$locations = [ $menu_locations[ $this->args['where']['location'] ] ];

			// if the $locations are NOT set and the user has proper capabilities, let the user query
			// all menu items connected to any menu
		} elseif ( current_user_can( 'edit_theme_options' ) ) {
			$locations = null;
		}

		// Only query for menu items in assigned locations.
		if ( ! empty( $locations ) && is_array( $locations ) ) {
			$query_args['tax_query'] = [
				[
					'taxonomy'         => 'nav_menu',
					'field'            => 'term_id',
					'terms'            => $locations,
					'include_children' => false,
					'operator'         => 'IN',
				],
			];
		}

		$default = parent::get_query_args();
		$args    = array_merge( $default, $query_args );

		return $args;
	}

}