MAPG-10 add GetNewPosition controller

remove position selecing from GuessController
adapt GuessController to the new view-controller concept

src/Controller/GetNewPosition.php

@@ -0,0 +1,28 @@
+<?php namespace MapGuesser\Controller;
+
+use MapGuesser\Util\Geo\Position;
+use MapGuesser\View\JsonView;
+use MapGuesser\View\ViewBase;
+use mysqli;
+
+class GetNewPosition implements ControllerInterface
+{
+    public function run(): ViewBase
+    {
+        $mysql = new mysqli($_ENV['DB_HOST'], $_ENV['DB_USER'], $_ENV['DB_PASSWORD'], $_ENV['DB_NAME']);
+
+        // demo map
+        $mapId = 1;
+
+        // using RAND() for the time being, could be changed in the future
+        $stmt = $mysql->prepare('SELECT lat, lng FROM places WHERE map_id=? ORDER BY RAND() LIMIT 1');
+        $stmt->bind_param("i", $mapId);
+        $stmt->execute();
+        $place = $stmt->get_result()->fetch_assoc();
+
+        $position = new Position($place['lat'], $place['lng']);
+
+        $data = ['position' => $position->toArray()];
+        return new JsonView($data);
+    }
+}