Start of ConfigMetadata

ConfigMetadata.php

<?php

namespace Drupal\Core\Config;

class ConfigMetadata {
  /**
   * @var \Drupal\Core\Config\Config
   */
  protected $config;

  /**
   * @var array
   */
  protected $data;

  /**
   * @var \Drupal\Core\Config\StorageInterface
   */
  protected $storage;

  /**
   * @var array
   */
  protected $metadata;

  /**
   * @var string
   */
  protected $pattern;

  function __construct(Config $config, StorageInterface $storage) {
    $this->config = $config;
    $this->storage = $storage;
  }

  public function get() {
    $this->flatten($this->config->get());
    return $this->read();
  }

  protected function flatten($config, $prefix = '') {
    foreach ($config as $key => $data) {
      $index = $prefix . $key;
      if (is_array($data)) {
        $this->flatten($data, $index . '.');
      }
      else {
        $this->data[$index] = $data;
      }
    }
  }

  protected function read() {
    $metadata = $this->readMeta($this->config->getName());
    $return = array();
    foreach ($this->data as $key => $value) {
      $matches = FALSE;
      if (isset($this->metadata[$key])) {
        $current_key = $key;
        $metadata_key= $key;
      }
      else {
        for ($current_key = $key; $current_key ; $current_key = substr($current_key, 0, strrpos($current_key, '.'))) {
          if (preg_match($this->pattern, $current_key, $matches)) {
            $metadata_key = $matches[1] . '*' . $matches[3];
            break;
          }
        }
      }
      if ($current_key) {
        $current = $metadata[$metadata_key];
        if (isset($current['include'])) {
          if (preg_match('/\[(.*)]/', $current['include'], $include_matches)) {
            $include_key = preg_replace($this->convertPattern($include_matches[1], '\[', '\]'), $matches[2], $current['include']);
          }
          else {
            $include_key = $current['include'];
          }
          $metadata += $this->readMeta($include_key, "$current_key.");
        }
        if (isset($metadata[$key])) {
          $return[$key] = $metadata[$key];
        }
      }
    }
    return $return;
  }

  protected function pattern($data) {
    $patterns = array();
    foreach (array_keys($data) as $key) {
      if (strpos($key, '*') !== FALSE) {
        $patterns[$key] = $this->convertPattern($key, '^', '$');
      }
    }
    if ($patterns) {
      if ($this->pattern) {
        $this->pattern .= '|';
      }
      $this->pattern .= implode('|', $patterns);
    }
  }

  protected function convertPattern($string, $start, $end) {
    return "/$start(" . str_replace('\*', ')(.*)(', preg_quote($string, '/')) . ")$end/";
  }

  protected function readMeta($filename, $prefix = '') {
    if (!$read = $this->storage->read("meta." . $filename)) {
      return array();
    }

    $metadata = array();
    foreach ($read as $key => $value) {
      $metadata[$prefix . $key] = $value;
    }
    $this->pattern($metadata);
    return $metadata;
  }

}