--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony CMF package.
+ *
+ * (c) 2011-2015 Symfony CMF
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Cmf\Component\Routing\Enhancer;
+
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * This enhancer can fill one field with the result of a hashmap lookup of
+ * another field. If the target field is already set, it does nothing.
+ *
+ * @author David Buchmann
+ */
+class FieldMapEnhancer implements RouteEnhancerInterface
+{
+ /**
+ * @var string field for key in hashmap lookup
+ */
+ protected $source;
+ /**
+ * @var string field to write hashmap lookup result into
+ */
+ protected $target;
+ /**
+ * @var array containing the mapping between the source field value and target field value
+ */
+ protected $hashmap;
+
+ /**
+ * @param string $source the field to read
+ * @param string $target the field to write the result of the lookup into
+ * @param array $hashmap for looking up value from source and get value for target
+ */
+ public function __construct($source, $target, array $hashmap)
+ {
+ $this->source = $source;
+ $this->target = $target;
+ $this->hashmap = $hashmap;
+ }
+
+ /**
+ * If the target field is not set but the source field is, map the field.
+ *
+ * {@inheritdoc}
+ */
+ public function enhance(array $defaults, Request $request)
+ {
+ if (isset($defaults[$this->target])) {
+ return $defaults;
+ }
+ if (!isset($defaults[$this->source])) {
+ return $defaults;
+ }
+ if (!isset($this->hashmap[$defaults[$this->source]])) {
+ return $defaults;
+ }
+
+ $defaults[$this->target] = $this->hashmap[$defaults[$this->source]];
+
+ return $defaults;
+ }
+}