Added geo distance sort

Author: Spamercz

src/Options/GeoDistanceSort.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Spameri\ElasticQuery\Options;
+
+
+/**
+ * @see https://www.elastic.co/guide/en/elasticsearch/reference/7.3/search-request-body.html#geo-sorting
+ */
+readonly class GeoDistanceSort implements \Spameri\ElasticQuery\Entity\EntityInterface
+{
+
+	public function __construct(
+		public string $field,
+		public float $lat,
+		public float $lon,
+		public string $type = Sort::ASC,
+		public string $unit = 'km',
+		public string $mode = 'min',
+		public string $distanceType = 'arc',
+	)
+	{
+		if ( ! \in_array($type, [Sort::ASC, Sort::DESC], true)) {
+			throw new \Spameri\ElasticQuery\Exception\InvalidArgumentException(
+				'Sorting type ' . $type . ' is out of allowed range. See \Spameri\ElasticQuery\Options\Sort for reference.',
+			);
+		}
+	}
+
+
+	public function key(): string
+	{
+		return $this->field;
+	}
+
+
+	public function toArray(): array
+	{
+		return [
+			'_geo_distance' => [
+				$this->field => [
+					$this->lat,
+					$this->lon,
+				],
+				'order' => $this->type,
+				"unit" => $this->unit,
+				"mode" => $this->mode,
+				"distance_type" => $this->distanceType,
+				"ignore_unmapped" => true,
+			],
+		];
+	}
+
+}