<?php

namespace Drupal\Core\Config;

use Drupal\Core\Config\StorageInterface;
use Drupal\Core\Config\ConfigException;

/**
 * Represents the default configuration storage object.
 */
class DrupalConfig {

  /**
   * The storage controllers to use.
   *
   * @var array
   */
  protected $storages;

  protected $storageInstances;

  /**
   * Config Objects.
   *
   * @var array
   */
  protected $configObjects = array();
  
  /**
   * Constructs a DrupalConfig object.
   *
   * @param array $storages
   *   An associative array defining the storage controllers to use and any
   *   required configuration for them; e.g.:
   *   @code
   *   array(
   *     'Drupal\Core\Config\DatabaseStorage' => array(
   *       'connection' => 'default',
   *       'read' => TRUE,
   *       'write' => TRUE,
   *     ),
   *     'Drupal\Core\Config\FileStorage' => array(
   *       'directory' => 'sites/default/files/config',
   *       'read' => TRUE,
   *       'write' => FALSE,
   *     ),
   *   )
   *   @endcode
   *
   * @todo $this should really know about $name and make it publicly accessible.
   */
  public function __construct($storages) {
    $this->storages = $storages;
  } 
  
  public function load($name) {
    $storage = $this->findStorage('read', $name);
    if (empty($this->configObjects[$name])) {
      $this->configObjects[$name] = new ConfigObject($name, $this->storages[$storage]);
    } 
    return $this->configObjects[$name];
  } 
  
  public function save($name, $data) {
    // Some logic to decide which storage to write to...
    $storage = $this->findStorage('write', $name);
    $this->storages[$storage]->write($name, $data);
  }

  public function delete($name) {
    // Some logic to decide which storage to write to...
    $storage = $this->findStorage('write', $name);
    $this->storage->delete($name);
  }

  public function findStorage($op, $name) {
    foreach ($this->storages as $class => $storage_config) {
      // Take the first storage that allows $op.
      if (!empty($storage_config[$op])) {
        break;
      }
    }
    if (!isset($this->storageInstances[$class])) {
      $this->storageInstances[$class] = new $class($storage_config);
    }
    return $this->storageInstances[$class];
  }

  /**
   * More site-level stuff here, like config sync...
   */
}