split parser and add tests

src/Demo/RawParser.php

@@ -0,0 +1,27 @@
+<?php declare(strict_types=1);
+
+namespace Demostf\API\Demo;
+
+use GuzzleHttp\Client;
+
+/**
+ * Wrapper around demo.js parser
+ *
+ * Doesn't do any post-processing on the result
+ */
+class RawParser {
+	/** @var string */
+	private $parserUrl;
+
+	public function __construct(string $parserUrl) {
+		$this->parserUrl = $parserUrl;
+	}
+
+	public function parse(string $path): ?array {
+		$client = new Client();
+		$response = $client->post($this->parserUrl, [
+			'body' => fopen($path, 'r')
+		]);
+		return json_decode($response->getBody(), true);
+	}
+}