FieldMapEnhancer.php

<?php

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;
  }

}