insideout10 / wordlift-plugin

src/includes/class-wordlift-relation-service.php

Indentation +428 added lines, -428 removed lines

@@ -18,404 +18,404 @@ 
  */
 class Wordlift_Relation_Service {
 
-	/**
-	 * The relation table name in MySQL, set during instantiation.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var string $relation_table The relation table name.
-	 */
-	private $relation_table;
-
-	/**
-	 * A {@link Wordlift_Log_Service} instance.
-	 *
-	 * @since 3.15.3
-	 *
-	 * @var Wordlift_Log_Service $log A {@link Wordlift_Log_Service} instance.
-	 */
-	private static $log;
-
-	/**
-	 * Create a {@link Wordlift_Relation_Service} instance.
-	 *
-	 * @since 3.15.0
-	 */
-	protected function __construct() {
-		global $wpdb;
-
-		self::$log = Wordlift_Log_Service::get_logger( get_class() );
-
-		// The relations table.
-		$this->relation_table = "{$wpdb->prefix}wl_relation_instances";
-
-	}
-
-	/**
-	 * The singleton instance.
-	 *
-	 * @since  3.15.0
-	 * @access private
-	 * @var Wordlift_Relation_Service $instance The singleton instance.
-	 */
-	private static $instance = null;
-
-	/**
-	 * Get the singleton instance.
-	 *
-	 * @return Wordlift_Relation_Service The {@link Wordlift_Relation_Service} singleton instance.
-	 * @since  3.15.0
-	 * @access public
-	 */
-	public static function get_instance() {
-
-		if ( ! isset( self::$instance ) ) {
-			self::$instance = new self();
-		}
-
-		return self::$instance;
-	}
-
-	/**
-	 * Get the articles referencing the specified entity {@link WP_Post}.
-	 *
-	 * @param int|array     $object_id The entity {@link WP_Post}'s id.
-	 * @param string        $fields The fields to return, 'ids' to only return ids or
-	 *                                      '*' to return all fields, by default '*'.
-	 * @param null|string   $predicate The predicate (who|what|...), by default all.
-	 * @param null|string   $status The status, by default all.
-	 * @param array         $excludes An array of ids to exclude from the results.
-	 * @param null|int      $limit The maximum number of results, by default
-	 *                                    no limit.
-	 * @param null|array    $include The {@link WP_Post}s' ids to include.
-	 *
-	 * @param null | string $order_by
-	 *
-	 * @param array         $post_types
-	 *
-	 * @return array|object|null Database query results
-	 * @since 3.15.0
-	 */
-	public function get_article_subjects( $object_id, $fields = '*', $predicate = null, $status = null, $excludes = array(), $limit = null, $include = null, $order_by = null, $post_types = array(), $offset = null ) {
-		global $wpdb;
-
-		// The output fields.
-		$actual_fields = self::fields( $fields );
-
-		self::$log->trace( 'Getting article subjects for object ' . implode( ', ', (array) $object_id ) . '...' );
-
-		$objects = $this->article_id_to_entity_id( $object_id );
-
-		// If there are no related objects, return an empty array.
-		if ( empty( $objects ) ) {
-			self::$log->debug( 'No entities found for object ' . implode( ', ', (array) $object_id ) . '.' );
-
-			return array();
-		}
-
-		self::$log->debug( count( $objects ) . ' entity id(s) found for object ' . implode( ', ', (array) $object_id ) . '.' );
-
-		$sql =
-			"
+    /**
+     * The relation table name in MySQL, set during instantiation.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var string $relation_table The relation table name.
+     */
+    private $relation_table;
+
+    /**
+     * A {@link Wordlift_Log_Service} instance.
+     *
+     * @since 3.15.3
+     *
+     * @var Wordlift_Log_Service $log A {@link Wordlift_Log_Service} instance.
+     */
+    private static $log;
+
+    /**
+     * Create a {@link Wordlift_Relation_Service} instance.
+     *
+     * @since 3.15.0
+     */
+    protected function __construct() {
+        global $wpdb;
+
+        self::$log = Wordlift_Log_Service::get_logger( get_class() );
+
+        // The relations table.
+        $this->relation_table = "{$wpdb->prefix}wl_relation_instances";
+
+    }
+
+    /**
+     * The singleton instance.
+     *
+     * @since  3.15.0
+     * @access private
+     * @var Wordlift_Relation_Service $instance The singleton instance.
+     */
+    private static $instance = null;
+
+    /**
+     * Get the singleton instance.
+     *
+     * @return Wordlift_Relation_Service The {@link Wordlift_Relation_Service} singleton instance.
+     * @since  3.15.0
+     * @access public
+     */
+    public static function get_instance() {
+
+        if ( ! isset( self::$instance ) ) {
+            self::$instance = new self();
+        }
+
+        return self::$instance;
+    }
+
+    /**
+     * Get the articles referencing the specified entity {@link WP_Post}.
+     *
+     * @param int|array     $object_id The entity {@link WP_Post}'s id.
+     * @param string        $fields The fields to return, 'ids' to only return ids or
+     *                                      '*' to return all fields, by default '*'.
+     * @param null|string   $predicate The predicate (who|what|...), by default all.
+     * @param null|string   $status The status, by default all.
+     * @param array         $excludes An array of ids to exclude from the results.
+     * @param null|int      $limit The maximum number of results, by default
+     *                                    no limit.
+     * @param null|array    $include The {@link WP_Post}s' ids to include.
+     *
+     * @param null | string $order_by
+     *
+     * @param array         $post_types
+     *
+     * @return array|object|null Database query results
+     * @since 3.15.0
+     */
+    public function get_article_subjects( $object_id, $fields = '*', $predicate = null, $status = null, $excludes = array(), $limit = null, $include = null, $order_by = null, $post_types = array(), $offset = null ) {
+        global $wpdb;
+
+        // The output fields.
+        $actual_fields = self::fields( $fields );
+
+        self::$log->trace( 'Getting article subjects for object ' . implode( ', ', (array) $object_id ) . '...' );
+
+        $objects = $this->article_id_to_entity_id( $object_id );
+
+        // If there are no related objects, return an empty array.
+        if ( empty( $objects ) ) {
+            self::$log->debug( 'No entities found for object ' . implode( ', ', (array) $object_id ) . '.' );
+
+            return array();
+        }
+
+        self::$log->debug( count( $objects ) . ' entity id(s) found for object ' . implode( ', ', (array) $object_id ) . '.' );
+
+        $sql =
+            "
 			SELECT DISTINCT p.$actual_fields
 			FROM {$this->relation_table} r
 			INNER JOIN $wpdb->posts p
 				ON p.id = r.subject_id
 			"
-			// Add the status clause.
-			. self::and_status( $status )
-			. self::inner_join_is_article()
-			. self::where_object_id( $objects )
-			// Since `object_id` can be an article ID we need to exclude it from
-			// the results.
-			. self::and_article_not_in( array_merge( $excludes, (array) $object_id ) )
-			. self::and_article_in( $include )
-			. self::and_post_type_in( $post_types )
-			. self::and_predicate( $predicate )
-			. self::order_by( $order_by )
-			. self::limit( $limit )
-			. self::offset( $offset );
-
-		return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql );  // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-	}
-
-	/**
-	 * The `post_type IN` clause.
-	 *
-	 * @param array $post_types If the post type is not provided then the valid
-	 * entity post types are used.
-	 *
-	 * @return string The `post_type IN` clause.
-	 * @since 3.15.3
-	 */
-	private static function and_post_type_in( $post_types = array() ) {
-
-		if ( array() === $post_types ) {
-			$post_types = Wordlift_Entity_Service::valid_entity_post_types();
-		}
-
-		return " AND p.post_type IN ( '"
-			. implode(
-				"','",
-				array_map( 'esc_sql', $post_types )
-			)
-			   . "' )";
-	}
-
-	/**
-	 * Add the limit clause if specified.
-	 *
-	 * @param null|int $limit The maximum number of results.
-	 *
-	 * @return string The limit clause (empty if no limit has been specified).
-	 * @since 3.15.0
-	 */
-	private static function limit( $limit = null ) {
-
-		if ( null === $limit ) {
-			return '';
-		}
-
-		return "LIMIT $limit";
-	}
-
-	/**
-	 * Add the OFFSET clause if specified.
-	 *
-	 * @param null|int $offset The number of results to skip.
-	 *
-	 * @return string The offset clause (empty if no offset has been specified).
-	 * @since 3.35.11
-	 */
-	private static function offset( $offset = null ) {
-
-		if ( null === $offset || ! is_numeric( $offset ) ) {
-			return '';
-		}
-
-		return " OFFSET $offset";
-	}
-
-	/**
-	 * @param $order_by string | null
-	 *
-	 * @return string
-	 */
-	private static function order_by( $order_by ) {
-		if ( ! $order_by ) {
-			return '';
-		}
-		$order_by         = (string) $order_by;
-		$order_by_clauses = array( 'DESC', 'ASC' );
-
-		if ( in_array( $order_by, $order_by_clauses, true ) ) {
-			return " ORDER BY p.post_modified ${order_by} ";
-		} else {
-			return ' ORDER BY p.post_modified DESC ';
-		}
-	}
-
-	/**
-	 * Map the provided ids into entities (i.e. return the id if it's an entity
-	 * or get the entities if it's a post).
-	 *
-	 * @param int|array $object_id An array of posts/entities' ids.
-	 *
-	 * @return array An array of entities' ids.
-	 * @since 3.15.0
-	 */
-	private function article_id_to_entity_id( $object_id ) {
-
-		$entity_service = Wordlift_Entity_Service::get_instance();
-
-		$relation_service = $this;
-
-		return array_reduce(
-			(array) $object_id,
-			function ( $carry, $item ) use ( $entity_service, $relation_service ) {
-				if ( $entity_service->is_entity( $item ) ) {
-					return array_merge( $carry, (array) $item );
-				}
-
-				return array_merge( $carry, $relation_service->get_objects( $item, 'ids' ) );
-			},
-			array()
-		);
-
-	}
-
-	/**
-	 * Add the WHERE clause.
-	 *
-	 * @param int|array $object_id An array of {@link WP_Post}s' ids.
-	 *
-	 * @return string The WHERE clause.
-	 * @since 3.15.0
-	 */
-	private static function where_object_id( $object_id ) {
-
-		if ( empty( $object_id ) ) {
-			// self::$log->warn( sprintf( "%s `where_object_id` called with empty `object_id`.", var_export( debug_backtrace( false, 3 ), true ) ) );
-
-			return ' WHERE 1 = 1';
-		}
-
-		return ' WHERE r.object_id IN ( ' . implode( ',', wp_parse_id_list( (array) $object_id ) ) . ' )';
-	}
-
-	/**
-	 * Add the exclude clause.
-	 *
-	 * @param int|array $exclude An array of {@link WP_Post}s' ids to exclude.
-	 *
-	 * @return string The exclude clause.
-	 * @since 3.15.0
-	 */
-	private static function and_article_not_in( $exclude ) {
-
-		return ' AND NOT p.ID IN ( ' . implode( ',', wp_parse_id_list( (array) $exclude ) ) . ' )';
-	}
-
-	/**
-	 * Add the include clause.
-	 *
-	 * @param null|int|array $include An array of {@link WP_Post}s' ids.
-	 *
-	 * @return string An empty string if $include is null otherwise the include
-	 *                clause.
-	 * @since 3.15.0
-	 */
-	private static function and_article_in( $include = null ) {
-
-		if ( null === $include ) {
-			return '';
-		}
-
-		return ' AND p.ID IN ( ' . implode( ',', wp_parse_id_list( (array) $include ) ) . ' )';
-	}
-
-	/**
-	 * Get the entities' {@link WP_Post}s' ids referencing the specified {@link WP_Post}.
-	 *
-	 * @param int         $object_id The object {@link WP_Post}'s id.
-	 * @param string      $fields The fields to return, 'ids' to only return ids or
-	 *                                    '*' to return all fields, by default '*'.
-	 * @param null|string $status The status, by default all.
-	 *
-	 * @return array|object|null Database query results
-	 * @since 3.15.0
-	 */
-	public function get_non_article_subjects( $object_id, $fields = '*', $status = null ) {
-		global $wpdb;
-
-		// The output fields.
-		$actual_fields = self::fields( $fields );
-
-		$sql = $wpdb->prepare(
-			"SELECT p.$actual_fields FROM {$wpdb->prefix}wl_relation_instances r INNER JOIN $wpdb->posts p ON p.id = r.subject_id" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
-			// Add the status clause.
-			. self::and_status( $status ) // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			. self::inner_join_is_not_article() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			. ' WHERE r.object_id = %d '
-			. self::and_post_type_in(), // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			$object_id
-		);
-
-		return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-	}
-
-	/**
-	 * Get the entities referenced by the specified {@link WP_Post}.
-	 *
-	 * @param int         $subject_id The {@link WP_Post}'s id.
-	 * @param string      $fields The fields to return, 'ids' to only return ids or
-	 *                                     '*' to return all fields, by default '*'.
-	 * @param null|string $predicate The predicate (who|what|...), by default all.
-	 * @param null|string $status The status, by default all.
-	 *
-	 * @return array|object|null Database query results
-	 * @since 3.15.0
-	 */
-	public function get_objects( $subject_id, $fields = '*', $predicate = null, $status = null ) {
-		global $wpdb;
-
-		// The output fields.
-		$actual_fields = self::fields( $fields );
-
-		$sql = $wpdb->prepare(
-			"SELECT p.$actual_fields FROM {$this->relation_table} r INNER JOIN $wpdb->posts p ON p.id = r.object_id" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
-			// Add the status clause.
-			. self::and_status( $status ) // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			. self::inner_join_is_not_article() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			. ' WHERE r.subject_id = %d '
-			. self::and_post_type_in() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			. self::and_predicate( $predicate ), // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-			$subject_id
-		);
-
-		return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
-	}
-
-	/**
-	 * Add the `post_status` clause.
-	 *
-	 * @param null|string|array $status The status values.
-	 *
-	 * @return string An empty string if $status is null, otherwise the status clause.
-	 * @since 3.15.0
-	 */
-	private static function and_status( $status = null ) {
-
-		if ( null === $status ) {
-			return '';
-		}
-
-		return " AND p.post_status IN ('" . implode( "', '", array_map( 'esc_sql', (array) $status ) ) . "')";
-	}
-
-	/**
-	 * Add the `predicate` clause.
-	 *
-	 * @param null|string|array $predicate An array of predicates.
-	 *
-	 * @return string An empty string if $predicate is null otherwise the predicate
-	 *                clause.
-	 * @since 3.15.0
-	 */
-	private static function and_predicate( $predicate = null ) {
-
-		if ( null === $predicate ) {
-			return '';
-		}
-
-		return " AND r.predicate IN ('" . implode( "', '", array_map( 'esc_sql', (array) $predicate ) ) . "')";
-	}
-
-	/**
-	 * The select fields.
-	 *
-	 * @param string $fields Either 'ids' or '*', by default '*'.
-	 *
-	 * @return string The `id` field if `ids` otherwise `*`.
-	 * @since 3.15.0
-	 */
-	private static function fields( $fields = '*' ) {
-
-		// The output fields.
-		return 'ids' === $fields ? 'id' : '*';
-	}
-
-	/**
-	 * The inner join clause for articles.
-	 *
-	 * @return string The articles inner join clause.
-	 * @since 3.15.0
-	 */
-	private static function inner_join_is_article() {
-		global $wpdb;
-
-		return $wpdb->prepare(
-			"
+            // Add the status clause.
+            . self::and_status( $status )
+            . self::inner_join_is_article()
+            . self::where_object_id( $objects )
+            // Since `object_id` can be an article ID we need to exclude it from
+            // the results.
+            . self::and_article_not_in( array_merge( $excludes, (array) $object_id ) )
+            . self::and_article_in( $include )
+            . self::and_post_type_in( $post_types )
+            . self::and_predicate( $predicate )
+            . self::order_by( $order_by )
+            . self::limit( $limit )
+            . self::offset( $offset );
+
+        return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql );  // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+    }
+
+    /**
+     * The `post_type IN` clause.
+     *
+     * @param array $post_types If the post type is not provided then the valid
+     * entity post types are used.
+     *
+     * @return string The `post_type IN` clause.
+     * @since 3.15.3
+     */
+    private static function and_post_type_in( $post_types = array() ) {
+
+        if ( array() === $post_types ) {
+            $post_types = Wordlift_Entity_Service::valid_entity_post_types();
+        }
+
+        return " AND p.post_type IN ( '"
+            . implode(
+                "','",
+                array_map( 'esc_sql', $post_types )
+            )
+                . "' )";
+    }
+
+    /**
+     * Add the limit clause if specified.
+     *
+     * @param null|int $limit The maximum number of results.
+     *
+     * @return string The limit clause (empty if no limit has been specified).
+     * @since 3.15.0
+     */
+    private static function limit( $limit = null ) {
+
+        if ( null === $limit ) {
+            return '';
+        }
+
+        return "LIMIT $limit";
+    }
+
+    /**
+     * Add the OFFSET clause if specified.
+     *
+     * @param null|int $offset The number of results to skip.
+     *
+     * @return string The offset clause (empty if no offset has been specified).
+     * @since 3.35.11
+     */
+    private static function offset( $offset = null ) {
+
+        if ( null === $offset || ! is_numeric( $offset ) ) {
+            return '';
+        }
+
+        return " OFFSET $offset";
+    }
+
+    /**
+     * @param $order_by string | null
+     *
+     * @return string
+     */
+    private static function order_by( $order_by ) {
+        if ( ! $order_by ) {
+            return '';
+        }
+        $order_by         = (string) $order_by;
+        $order_by_clauses = array( 'DESC', 'ASC' );
+
+        if ( in_array( $order_by, $order_by_clauses, true ) ) {
+            return " ORDER BY p.post_modified ${order_by} ";
+        } else {
+            return ' ORDER BY p.post_modified DESC ';
+        }
+    }
+
+    /**
+     * Map the provided ids into entities (i.e. return the id if it's an entity
+     * or get the entities if it's a post).
+     *
+     * @param int|array $object_id An array of posts/entities' ids.
+     *
+     * @return array An array of entities' ids.
+     * @since 3.15.0
+     */
+    private function article_id_to_entity_id( $object_id ) {
+
+        $entity_service = Wordlift_Entity_Service::get_instance();
+
+        $relation_service = $this;
+
+        return array_reduce(
+            (array) $object_id,
+            function ( $carry, $item ) use ( $entity_service, $relation_service ) {
+                if ( $entity_service->is_entity( $item ) ) {
+                    return array_merge( $carry, (array) $item );
+                }
+
+                return array_merge( $carry, $relation_service->get_objects( $item, 'ids' ) );
+            },
+            array()
+        );
+
+    }
+
+    /**
+     * Add the WHERE clause.
+     *
+     * @param int|array $object_id An array of {@link WP_Post}s' ids.
+     *
+     * @return string The WHERE clause.
+     * @since 3.15.0
+     */
+    private static function where_object_id( $object_id ) {
+
+        if ( empty( $object_id ) ) {
+            // self::$log->warn( sprintf( "%s `where_object_id` called with empty `object_id`.", var_export( debug_backtrace( false, 3 ), true ) ) );
+
+            return ' WHERE 1 = 1';
+        }
+
+        return ' WHERE r.object_id IN ( ' . implode( ',', wp_parse_id_list( (array) $object_id ) ) . ' )';
+    }
+
+    /**
+     * Add the exclude clause.
+     *
+     * @param int|array $exclude An array of {@link WP_Post}s' ids to exclude.
+     *
+     * @return string The exclude clause.
+     * @since 3.15.0
+     */
+    private static function and_article_not_in( $exclude ) {
+
+        return ' AND NOT p.ID IN ( ' . implode( ',', wp_parse_id_list( (array) $exclude ) ) . ' )';
+    }
+
+    /**
+     * Add the include clause.
+     *
+     * @param null|int|array $include An array of {@link WP_Post}s' ids.
+     *
+     * @return string An empty string if $include is null otherwise the include
+     *                clause.
+     * @since 3.15.0
+     */
+    private static function and_article_in( $include = null ) {
+
+        if ( null === $include ) {
+            return '';
+        }
+
+        return ' AND p.ID IN ( ' . implode( ',', wp_parse_id_list( (array) $include ) ) . ' )';
+    }
+
+    /**
+     * Get the entities' {@link WP_Post}s' ids referencing the specified {@link WP_Post}.
+     *
+     * @param int         $object_id The object {@link WP_Post}'s id.
+     * @param string      $fields The fields to return, 'ids' to only return ids or
+     *                                    '*' to return all fields, by default '*'.
+     * @param null|string $status The status, by default all.
+     *
+     * @return array|object|null Database query results
+     * @since 3.15.0
+     */
+    public function get_non_article_subjects( $object_id, $fields = '*', $status = null ) {
+        global $wpdb;
+
+        // The output fields.
+        $actual_fields = self::fields( $fields );
+
+        $sql = $wpdb->prepare(
+            "SELECT p.$actual_fields FROM {$wpdb->prefix}wl_relation_instances r INNER JOIN $wpdb->posts p ON p.id = r.subject_id" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
+            // Add the status clause.
+            . self::and_status( $status ) // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            . self::inner_join_is_not_article() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            . ' WHERE r.object_id = %d '
+            . self::and_post_type_in(), // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            $object_id
+        );
+
+        return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+    }
+
+    /**
+     * Get the entities referenced by the specified {@link WP_Post}.
+     *
+     * @param int         $subject_id The {@link WP_Post}'s id.
+     * @param string      $fields The fields to return, 'ids' to only return ids or
+     *                                     '*' to return all fields, by default '*'.
+     * @param null|string $predicate The predicate (who|what|...), by default all.
+     * @param null|string $status The status, by default all.
+     *
+     * @return array|object|null Database query results
+     * @since 3.15.0
+     */
+    public function get_objects( $subject_id, $fields = '*', $predicate = null, $status = null ) {
+        global $wpdb;
+
+        // The output fields.
+        $actual_fields = self::fields( $fields );
+
+        $sql = $wpdb->prepare(
+            "SELECT p.$actual_fields FROM {$this->relation_table} r INNER JOIN $wpdb->posts p ON p.id = r.object_id" // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
+            // Add the status clause.
+            . self::and_status( $status ) // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            . self::inner_join_is_not_article() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            . ' WHERE r.subject_id = %d '
+            . self::and_post_type_in() // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            . self::and_predicate( $predicate ), // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+            $subject_id
+        );
+
+        return '*' === $actual_fields ? $wpdb->get_results( $sql ) : $wpdb->get_col( $sql ); // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared
+    }
+
+    /**
+     * Add the `post_status` clause.
+     *
+     * @param null|string|array $status The status values.
+     *
+     * @return string An empty string if $status is null, otherwise the status clause.
+     * @since 3.15.0
+     */
+    private static function and_status( $status = null ) {
+
+        if ( null === $status ) {
+            return '';
+        }
+
+        return " AND p.post_status IN ('" . implode( "', '", array_map( 'esc_sql', (array) $status ) ) . "')";
+    }
+
+    /**
+     * Add the `predicate` clause.
+     *
+     * @param null|string|array $predicate An array of predicates.
+     *
+     * @return string An empty string if $predicate is null otherwise the predicate
+     *                clause.
+     * @since 3.15.0
+     */
+    private static function and_predicate( $predicate = null ) {
+
+        if ( null === $predicate ) {
+            return '';
+        }
+
+        return " AND r.predicate IN ('" . implode( "', '", array_map( 'esc_sql', (array) $predicate ) ) . "')";
+    }
+
+    /**
+     * The select fields.
+     *
+     * @param string $fields Either 'ids' or '*', by default '*'.
+     *
+     * @return string The `id` field if `ids` otherwise `*`.
+     * @since 3.15.0
+     */
+    private static function fields( $fields = '*' ) {
+
+        // The output fields.
+        return 'ids' === $fields ? 'id' : '*';
+    }
+
+    /**
+     * The inner join clause for articles.
+     *
+     * @return string The articles inner join clause.
+     * @since 3.15.0
+     */
+    private static function inner_join_is_article() {
+        global $wpdb;
+
+        return $wpdb->prepare(
+            "
 			INNER JOIN $wpdb->term_relationships tr
 			 ON p.id = tr.object_id
 			INNER JOIN $wpdb->term_taxonomy tt
@@ -425,22 +425,22 @@ 
 			 ON t.term_id = tt.term_id
 			  AND t.slug = %s
 			",
-			'wl_entity_type',
-			'article'
-		);
-	}
-
-	/**
-	 * The inner join clause for non-articles.
-	 *
-	 * @return string The non-articles inner join clause.
-	 * @since 3.15.0
-	 */
-	private static function inner_join_is_not_article() {
-		global $wpdb;
-
-		return $wpdb->prepare(
-			"
+            'wl_entity_type',
+            'article'
+        );
+    }
+
+    /**
+     * The inner join clause for non-articles.
+     *
+     * @return string The non-articles inner join clause.
+     * @since 3.15.0
+     */
+    private static function inner_join_is_not_article() {
+        global $wpdb;
+
+        return $wpdb->prepare(
+            "
 			INNER JOIN $wpdb->term_relationships tr
 			 ON p.id = tr.object_id
 			INNER JOIN $wpdb->term_taxonomy tt
@@ -450,29 +450,29 @@ 
 			 ON t.term_id = tt.term_id
 			  AND NOT t.slug = %s
 			",
-			'wl_entity_type',
-			'article'
-		);
-	}
-
-	/**
-	 * Find all the subject IDs and their referenced/related object IDs. The
-	 * object IDs are returned as comma separated IDs in the `object_ids` key.
-	 *
-	 * @return mixed Database query results
-	 * @since 3.18.0
-	 */
-	public function find_all_grouped_by_subject_id() {
-		global $wpdb;
-
-		return $wpdb->get_results(
-			"
+            'wl_entity_type',
+            'article'
+        );
+    }
+
+    /**
+     * Find all the subject IDs and their referenced/related object IDs. The
+     * object IDs are returned as comma separated IDs in the `object_ids` key.
+     *
+     * @return mixed Database query results
+     * @since 3.18.0
+     */
+    public function find_all_grouped_by_subject_id() {
+        global $wpdb;
+
+        return $wpdb->get_results(
+            "
 			SELECT subject_id, GROUP_CONCAT( DISTINCT object_id ORDER BY object_id SEPARATOR ',' ) AS object_ids
 			FROM {$wpdb->prefix}wl_relation_instances
 			GROUP BY subject_id
 			"
-		);
+        );
 
-	}
+    }
 
 }