to add to the query builder.
	 * @param string                                       $label       The 'label' (unique id) for this aggregation.
	 * @param Automattic\Jetpack\Search\WPES\Query_Builder $builder     The builder instance that is creating the Elasticsearch query.
	 */
	public function add_post_type_aggregation_to_es_query_builder( array $aggregation, $label, $builder ) {
		$builder->add_aggs(
			$label,
			array(
				'terms' => array(
					'field' => 'post_type',
					'size'  => min( (int) $aggregation['count'], $this->max_aggregations_count ),
				),
			)
		);
	}

	/**
	 * Given an individual author aggregation, add it to the query builder object for use in Elasticsearch.
	 *
	 * @since 0.20.0
	 *
	 * @param array                                        $aggregation The aggregation to add to the query builder.
	 * @param string                                       $label       The 'label' (unique id) for this aggregation.
	 * @param Automattic\Jetpack\Search\WPES\Query_Builder $builder     The builder instance that is creating the Elasticsearch query.
	 */
	public function add_author_aggregation_to_es_query_builder( array $aggregation, $label, $builder ) {
		$builder->add_aggs(
			$label,
			array(
				'terms' => array(
					'field' => 'author_login_slash_name',
					'size'  => min( (int) $aggregation['count'], $this->max_aggregations_count ),
				),
			)
		);
	}

	/**
	 * Given an individual date_histogram aggregation, add it to the query builder object for use in Elasticsearch.
	 *
	 * @since 5.0.0
	 *
	 * @param array                                        $aggregation The aggregation to add to the query builder.
	 * @param string                                       $label       The 'label' (unique id) for this aggregation.
	 * @param Automattic\Jetpack\Search\WPES\Query_Builder $builder     The builder instance that is creating the Elasticsearch query.
	 */
	public function add_date_histogram_aggregation_to_es_query_builder( array $aggregation, $label, $builder ) {
		$args = array(
			'interval' => $aggregation['interval'],
			'field'    => ( ! empty( $aggregation['field'] ) && 'post_date_gmt' === $aggregation['field'] ) ? 'date_gmt' : 'date',
		);

		if ( isset( $aggregation['min_doc_count'] ) ) {
			$args['min_doc_count'] = (int) $aggregation['min_doc_count'];
		} else {
			$args['min_doc_count'] = 1;
		}

		$builder->add_aggs(
			$label,
			array(
				'date_histogram' => $args,
			)
		);
	}

	/**
	 * And an existing filter object with a list of additional filters.
	 *
	 * Attempts to optimize the filters somewhat.
	 *
	 * @since 5.0.0
	 *
	 * @param array $curr_filter The existing filters to build upon.
	 * @param array $filters     The new filters to add.
	 *
	 * @return array The resulting merged filters.
	 */
	public static function and_es_filters( array $curr_filter, array $filters ) {
		if ( ! is_array( $curr_filter ) || isset( $curr_filter['match_all'] ) ) {
			if ( 1 === count( $filters ) ) {
				return $filters[0];
			}

			return array(
				'and' => $filters,
			);
		}

		return array(
			'and' => array_merge( array( $curr_filter ), $filters ),
		);
	}

	/**
	 * Set the available filters for the search.
	 *
	 * These get rendered via the Jetpack_Search_Widget() widget.
	 *
	 * Behind the scenes, these are implemented using Elasticsearch Aggregations.
	 *
	 * If you do not require counts of how many documents match each filter, please consider using regular WP Query
	 * arguments instead, such as via the jetpack_search_es_wp_query_args filter
	 *
	 * @see    https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations.html
	 *
	 * @since  5.0.0
	 *
	 * @param array $aggregations Array of filters (aggregations) to apply to the search.
	 */
	public function set_filters( array $aggregations ) {
		foreach ( (array) $aggregations as $key => $agg ) {
			if ( empty( $agg['name'] ) ) {
				$aggregations[ $key ]['name'] = $key;
			}
		}
		$this->aggregations = $aggregations;
	}

	/**
	 * Get the raw Aggregation results from the Elasticsearch response.
	 *
	 * @since  5.0.0
	 *
	 * @see    https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations.html
	 *
	 * @return array Array of Aggregations performed on the search.
	 */
	public function get_search_aggregations_results() {
		$aggregations = array();

		$search_result = $this->get_search_result();

		if ( ! empty( $search_result ) && ! empty( $search_result['aggregations'] ) ) {
			$aggregations = $search_result['aggregations'];
		}

		return $aggregations;
	}

	/**
	 * Get the results of the Filters performed, including the number of matching documents.
	 *
	 * Returns an array of Filters (keyed by $label, as passed to Classic_Search::set_filters()), containing the Filter and all resulting
	 * matching buckets, the url for applying/removing each bucket, etc.
	 *
	 * NOTE - if this is called before the search is performed, an empty array will be returned. Use the $aggregations class
	 * member if you need to access the raw filters set in Classic_Search::set_filters().
	 *
	 * @since 5.0.0
	 *
	 * @param WP_Query $query The optional original WP_Query to use for determining which filters are active. Defaults to the main query.
	 *
	 * @return array Array of filters applied and info about them.
	 */
	public function get_filters( WP_Query $query = null ) {
		if ( ! $query instanceof WP_Query ) {
			global $wp_query;

			$query = $wp_query;
		}

		$aggregation_data = $this->aggregations;

		if ( empty( $aggregation_data ) ) {
			return $aggregation_data;
		}

		$aggregation_results = $this->get_search_aggregations_results();

		if ( ! $aggregation_results ) {
			return $aggregation_data;
		}

		// NOTE - Looping over the _results_, not the original configured aggregations, so we get the 'real' data from ES.
		foreach ( $aggregation_results as $label => $aggregation ) {
			if ( empty( $aggregation ) ) {
				continue;
			}

			$type = $this->aggregations[ $label ]['type'];

			$aggregation_data[ $label ]['buckets'] = array();

			$existing_term_slugs = array();

			$tax_query_var = null;

			// Figure out which terms are active in the query, for this taxonomy.
			if ( 'taxonomy' === $this->aggregations[ $label ]['type'] ) {
				$tax_query_var = $this->get_taxonomy_query_var( $this->aggregations[ $label ]['taxonomy'] );

				if ( ! empty( $query->tax_query ) && ! empty( $query->tax_query->queries ) && is_array( $query->tax_query->queries ) ) {
					foreach ( $query->tax_query->queries as $tax_query ) {
						if ( is_array( $tax_query ) && $this->aggregations[ $label ]['taxonomy'] === $tax_query['taxonomy'] &&
							'slug' === $tax_query['field'] &&
							is_array( $tax_query['terms'] ) ) {
							$existing_term_slugs = array_merge( $existing_term_slugs, $tax_query['terms'] );
						}
					}
				}
			}

			// Now take the resulting found aggregation items and generate the additional info about them, such as activation/deactivation url, name, count, etc.
			$buckets = array();

			if ( ! empty( $aggregation['buckets'] ) ) {
				$buckets = (array) $aggregation['buckets'];
			}

			if ( 'date_histogram' === $type ) {
				// re-order newest to oldest.
				$buckets = array_reverse( $buckets );
			}

			// Some aggregation types like date_histogram don't support the max results parameter.
			if ( is_int( $this->aggregations[ $label ]['count'] ) && count( $buckets ) > $this->aggregations[ $label ]['count'] ) {
				$buckets = array_slice( $buckets, 0, $this->aggregations[ $label ]['count'] );
			}

			foreach ( $buckets as $item ) {
				$query_vars = array();
				$active     = false;
				$remove_url = null;
				$name       = '';

				// What type was the original aggregation?
				switch ( $type ) {
					case 'taxonomy':
						$taxonomy = $this->aggregations[ $label ]['taxonomy'];

						$term = get_term_by( 'slug', $item['key'], $taxonomy );

						if ( ! $term || ! $tax_query_var ) {
							continue 2; // switch() is considered a looping structure.
						}

						$query_vars = array(
							$tax_query_var => implode( '+', array_merge( $existing_term_slugs, array( $term->slug ) ) ),
						);

						$name = $term->name;

						// Let's determine if this term is active or not.

						if ( in_array( $item['key'], $existing_term_slugs, true ) ) {
							$active = true;

							$slug_count = count( $existing_term_slugs );

							if ( $slug_count > 1 ) {
								$remove_url = Helper::add_query_arg(
									$tax_query_var,
									rawurlencode( implode( '+', array_diff( $existing_term_slugs, array( $item['key'] ) ) ) )
								);
							} else {
								$remove_url = Helper::remove_query_arg( $tax_query_var );
							}
						}

						break;

					case 'post_type':
						$post_type = get_post_type_object( $item['key'] );

						if ( ! $post_type || $post_type->exclude_from_search ) {
							continue 2;  // switch() is considered a looping structure.
						}

						$query_vars = array(
							'post_type' => $item['key'],
						);

						$name = $post_type->labels->singular_name;

						// Is this post type active on this search?
						$post_types = $query->get( 'post_type' );

						if ( ! is_array( $post_types ) ) {
							$post_types = array( $post_types );
						}

						if ( in_array( $item['key'], $post_types, true ) ) {
							$active = true;

							$post_type_count = count( $post_types );

							// For the right 'remove filter' url, we need to remove the post type from the array, or remove the param entirely if it's the only one.
							if ( $post_type_count > 1 ) {
								$remove_url = Helper::add_query_arg(
									'post_type',
									rawurlencode( implode( ',', array_diff( $post_types, array( $item['key'] ) ) ) )
								);
							} else {
								$remove_url = Helper::remove_query_arg( 'post_type' );
							}
						}

						break;

					// The `author` filter is NOT supported in Classic Search. This is used to keep the compatibility for filters outside the overlay with Instant Search.
					case 'author':
						$split_names = preg_split( '/\/(.?)/', $item['key'] );

						$name = '';

						if ( false !== $split_names ) {
							$name = $split_names[0];
						}

						if ( empty( $name ) ) {
							continue 2;  // switch() is considered a looping structure.
						}

						$query_vars = array(
							'author' => $name,
						);

						$active = true;

						$remove_url = Helper::remove_query_arg( 'author' );

						break;

					case 'date_histogram':
						$timestamp = $item['key'] / 1000;

						$current_year  = $query->get( 'year' );
						$current_month = $query->get( 'monthnum' );
						$current_day   = $query->get( 'day' );

						switch ( $this->aggregations[ $label ]['interval'] ) {
							case 'year':
								$year = (int) gmdate( 'Y', $timestamp );

								$query_vars = array(
									'year'     => $year,
									'monthnum' => false,
									'day'      => false,
								);

								$name = $year;

								// Is this year currently selected?
								if ( ! empty( $current_year ) && (int) $current_year === $year ) {
									$active = true;

									$remove_url = Helper::remove_query_arg( array( 'year', 'monthnum', 'day' ) );
								}

								break;

							case 'month':
								$year  = (int) gmdate( 'Y', $timestamp );
								$month = (int) gmdate( 'n', $timestamp );

								$query_vars = array(
									'year'     => $year,
									'monthnum' => $month,
									'day'      => false,
								);

								$name = gmdate( 'F Y', $timestamp );

								// Is this month currently selected?
								if ( ! empty( $current_year ) && (int) $current_year === $year &&
									! empty( $current_month ) && (int) $current_month === $month ) {
									$active = true;

									$remove_url = Helper::remove_query_arg( array( 'year', 'monthnum' ) );
								}

								break;

							case 'day':
								$year  = (int) gmdate( 'Y', $timestamp );
								$month = (int) gmdate( 'n', $timestamp );
								$day   = (int) gmdate( 'j', $timestamp );

								$query_vars = array(
									'year'     => $year,
									'monthnum' => $month,
									'day'      => $day,
								);

								$name = gmdate( 'F jS, Y', $timestamp );

								// Is this day currently selected?
								if ( ! empty( $current_year ) && (int) $current_year === $year &&
									! empty( $current_month ) && (int) $current_month === $month &&
									! empty( $current_day ) && (int) $current_day === $day ) {
									$active = true;

									$remove_url = Helper::remove_query_arg( array( 'day' ) );
								}

								break;

							default:
								continue 3; // switch() is considered a looping structure.
						} // End switch.

						break;

					default:
						// continue 2; // switch() is considered a looping structure.
				} // End switch.

				// Need to urlencode param values since add_query_arg doesn't.
				$url_params = urlencode_deep( $query_vars );

				$aggregation_data[ $label ]['buckets'][] = array(
					'url'        => Helper::add_query_arg( $url_params ),
					'query_vars' => $query_vars,
					'name'       => $name,
					'count'      => $item['doc_count'],
					'active'     => $active,
					'remove_url' => $remove_url,
					'type'       => $type,
					'type_label' => $aggregation_data[ $label ]['name'],
					'widget_id'  => ! empty( $aggregation_data[ $label ]['widget_id'] ) ? $aggregation_data[ $label ]['widget_id'] : 0,
				);
			} // End foreach.
		} // End foreach.

		/**
		 * Modify the aggregation filters returned by get_filters().
		 *
		 * Useful if you are setting custom filters outside of the supported filters (taxonomy, post_type etc.) and
		 * want to hook them up so they're returned when you call `get_filters()`.
		 *
		 * @module search
		 *
		 * @since  6.9.0
		 *
		 * @param array    $aggregation_data The array of filters keyed on label.
		 * @param WP_Query $query            The WP_Query object.
		 */
		return apply_filters( 'jetpack_search_get_filters', $aggregation_data, $query );
	}

	/**
	 * Get the filters that are currently applied to this search.
	 *
	 * @since 5.0.0
	 *
	 * @return array Array of filters that were applied.
	 */
	public function get_active_filter_buckets() {
		$active_buckets = array();

		$filters = $this->get_filters();

		if ( ! is_array( $filters ) ) {
			return $active_buckets;
		}

		foreach ( $filters as $filter ) {
			if ( isset( $filter['buckets'] ) && is_array( $filter['buckets'] ) ) {
				foreach ( $filter['buckets'] as $item ) {
					if ( isset( $item['active'] ) && $item['active'] ) {
						$active_buckets[] = $item;
					}
				}
			}
		}

		return $active_buckets;
	}

	/**
	 * Calculate the right query var to use for a given taxonomy.
	 *
	 * Allows custom code to modify the GET var that is used to represent a given taxonomy, via the jetpack_search_taxonomy_query_var filter.
	 *
	 * @since 5.0.0
	 *
	 * @param string $taxonomy_name The name of the taxonomy for which to get the query var.
	 *
	 * @return bool|string The query var to use for this taxonomy, or false if none found.
	 */
	public function get_taxonomy_query_var( $taxonomy_name ) {
		$taxonomy = get_taxonomy( $taxonomy_name );

		if ( ! $taxonomy || is_wp_error( $taxonomy ) ) {
			return false;
		}

		/**
		 * Modify the query var to use for a given taxonomy
		 *
		 * @module search
		 *
		 * @since  5.0.0
		 *
		 * @param string $query_var     The current query_var for the taxonomy
		 * @param string $taxonomy_name The taxonomy name
		 */
		return apply_filters( 'jetpack_search_taxonomy_query_var', $taxonomy->query_var, $taxonomy_name );
	}

	/**
	 * Takes an array of aggregation results, and ensures the array key ordering matches the key order in $desired
	 * which is the input order.
	 *
	 * Necessary because ES does not always return aggregations in the same order that you pass them in,
	 * and it should be possible to control the display order easily.
	 *
	 * @since 5.0.0
	 *
	 * @param array $aggregations Aggregation results to be reordered.
	 * @param array $desired      Array with keys representing the desired ordering.
	 *
	 * @return array A new array with reordered keys, matching those in $desired.
	 */
	public function fix_aggregation_ordering( array $aggregations, array $desired ) {
		if ( empty( $aggregations ) || empty( $desired ) ) {
			return $aggregations;
		}

		$reordered = array();

		foreach ( array_keys( $desired ) as $agg_name ) {
			if ( isset( $aggregations[ $agg_name ] ) ) {
				$reordered[ $agg_name ] = $aggregations[ $agg_name ];
			}
		}

		return $reordered;
	}

	/**
	 * Sends events to Tracks when a search filters widget is updated.
	 *
	 * @since 5.8.0
	 *
	 * @param string $option    The option name. Only "widget_jetpack-search-filters" is cared about.
	 * @param array  $old_value The old option value.
	 * @param array  $new_value The new option value.
	 */
	public function track_widget_updates( $option, $old_value, $new_value ) {
		if ( 'widget_jetpack-search-filters' !== $option ) {
			return;
		}

		$event = Helper::get_widget_tracks_value( $old_value, $new_value );
		if ( ! $event ) {
			return;
		}

		$tracking = new \Automattic\Jetpack\Tracking();
		$tracking->tracks_record_event(
			wp_get_current_user(),
			sprintf( 'jetpack_search_widget_%s', $event['action'] ),
			$event['widget']
		);
	}

	/**
	 * Moves any active search widgets to the inactive category.
	 *
	 * @since 5.9.0
	 */
	public function move_search_widgets_to_inactive() {
		if ( ! is_active_widget( false, false, Helper::FILTER_WIDGET_BASE, true ) ) {
			return;
		}

		$sidebars_widgets = wp_get_sidebars_widgets();

		if ( ! is_array( $sidebars_widgets ) ) {
			return;
		}

		$changed = false;

		foreach ( $sidebars_widgets as $sidebar => $widgets ) {
			if ( 'wp_inactive_widgets' === $sidebar || str_starts_with( $sidebar, 'orphaned_widgets' ) ) {
				continue;
			}

			if ( is_array( $widgets ) ) {
				foreach ( $widgets as $key => $widget ) {
					if ( _get_widget_id_base( $widget ) === Helper::FILTER_WIDGET_BASE ) {
						$changed = true;

						array_unshift( $sidebars_widgets['wp_inactive_widgets'], $widget );
						unset( $sidebars_widgets[ $sidebar ][ $key ] );
					}
				}
			}
		}

		if ( $changed ) {
			wp_set_sidebars_widgets( $sidebars_widgets );
		}
	}

	/**
	 * Determine whether a given WP_Query should be handled by ElasticSearch.
	 *
	 * @param WP_Query $query The WP_Query object.
	 *
	 * @return bool
	 */
	public function should_handle_query( $query ) {
		/**
		 * Determine whether a given WP_Query should be handled by ElasticSearch.
		 *
		 * @module search
		 *
		 * @since  5.6.0
		 *
		 * @param bool     $should_handle Should be handled by Jetpack Search.
		 * @param WP_Query $query         The WP_Query object.
		 */
		return apply_filters( 'jetpack_search_should_handle_query', $query->is_main_query() && $query->is_search(), $query );
	}

	/**
	 * Transforms an array with fields name as keys and boosts as value into
	 * shorthand "caret" format.
	 *
	 * @param array $fields_boost [ "title" => "2", "content" => "1" ].
	 *
	 * @return array [ "title^2", "content^1" ]
	 */
	private function _get_caret_boosted_fields( array $fields_boost ) { // phpcs:ignore PSR2.Methods.MethodDeclaration.Underscore
		$caret_boosted_fields = array();
		foreach ( $fields_boost as $field => $boost ) {
			$caret_boosted_fields[] = "$field^$boost";
		}
		return $caret_boosted_fields;
	}

	/**
	 * Apply a multiplier to boost values.
	 *
	 * @param array $fields_boost [ "title" => 2, "content" => 1 ].
	 * @param array $fields_boost_multiplier [ "title" => 0.1234 ].
	 *
	 * @return array [ "title" => "0.247", "content" => "1.000" ]
	 */
	private function _apply_boosts_multiplier( array $fields_boost, array $fields_boost_multiplier ) { // phpcs:ignore PSR2.Methods.MethodDeclaration.Underscore
		foreach ( $fields_boost as $field_name => $field_boost ) {
			if ( isset( $fields_boost_multiplier[ $field_name ] ) ) {
				$fields_boost[ $field_name ] *= $fields_boost_multiplier[ $field_name ];
			}

			// Set a floor and format the number as string.
			$fields_boost[ $field_name ] = number_format(
				max( 0.001, $fields_boost[ $field_name ] ),
				3,
				'.',
				''
			);
		}

		return $fields_boost;
	}
}