Rework filter handling (Fixes #50).

src/Filter/FilterFactory.php

@@ -0,0 +1,59 @@
+<?php
+
+/**
+ * Leaflet maps for Contao CMS.
+ *
+ * @package    contao-leaflet-maps
+ * @author     David Molineus <david.molineus@netzmacht.de>
+ * @copyright  2016-2017 netzmacht David Molineus. All rights reserved.
+ * @license    LGPL-3.0 https://github.com/netzmacht/contao-leaflet-maps/blob/master/LICENSE
+ * @filesource
+ */
+
+declare(strict_types=1);
+
+namespace Netzmacht\Contao\Leaflet\Filter;
+
+/**
+ * Class FilterFactory.
+ *
+ * @package Netzmacht\Contao\Leaflet\Filter
+ */
+final class FilterFactory
+{
+    /**
+     * Map of filter classes.
+     *
+     * @var array
+     */
+    private $filters;
+
+    /**
+     * FilterFactory constructor.
+     *
+     * @param array $filters Map of filter classes.
+     */
+    public function __construct(array $filters)
+    {
+        $this->filters = $filters;
+    }
+
+    /**
+     * Create a filter.
+     *
+     * @param string $filter Filter name.
+     * @param string $values Filter values.
+     *
+     * @return Filter
+     *
+     * @throws \RuntimeException When filter is not supported.
+     */
+    public function create(string $filter, string $values): Filter
+    {
+        if (isset($this->filters[$filter])) {
+            return call_user_func([$filter, 'fromRequest'], $values);
+        }
+
+        throw new \RuntimeException(sprintf('Creating filter failed. Unsupported filter "%s"', $filter));
+    }
+}