Added phrase prefix query

Author: Spamercz

src/Query/PhrasePrefix.php

@@ -0,0 +1,49 @@
+<?php declare(strict_types = 1);
+
+namespace Spameri\ElasticQuery\Query;
+
+class PhrasePrefix implements \Spameri\ElasticQuery\Query\LeafQueryInterface
+{
+
+	private string $field;
+
+	private string $queryString;
+
+	private int $boost;
+
+	private int $slop;
+
+
+	public function __construct(
+		string $field,
+		string $queryString,
+		int $boost = 1,
+		int $slop = 1
+	) {
+		$this->field = $field;
+		$this->queryString = $queryString;
+		$this->boost = $boost;
+		$this->slop = $slop;
+	}
+
+
+	public function key(): string
+	{
+		return 'phrase_prefix_' . $this->field . '_' . $this->queryString;
+	}
+
+
+	public function toArray(): array
+	{
+		return [
+			'match_phrase_prefix' => [
+				$this->field => [
+					'query' => $this->queryString,
+					'boost' => $this->boost,
+					'slop' => $this->slop,
+				],
+			],
+		];
+	}
+
+}