Laravel 4 dynamic relation definitions

gistfile1.txt

/// SampleModel

class SampleModel extends BaseEloquent
{
  protected $table = 'sample_models';
  protected $associations = array(
    'publishingRule' => array(
      'belongsTo' => 'PublishingRule'
    ),
    'previewImage' => array(
      'belongsTo' => 'PreviewImage'
    ),
  );
}


/// BaseEloquent

abstract class BaseEloquent extends Eloquent
{
  public function __call($method, $args)
  {
    if($this->isAssociationMethod($method)) {
      return $this->getAssociation($method);
    }

    return parent::__call($method, $args);
  }

  private function isAssociationMethod($method)
  {
    $hasAssociations = is_array($this->associations);

    return $hasAssociations && array_key_exists($method, $this->associations);
  }

  private function getAssociation($association)
  {
    $associationDetails = $this->getAssociationDetails($association);
    $associationType = $this->getAssociationType($associationDetails);
    $typeDetails = $this->getAssociationTypeDetails(
      $association,
      $associationType,
      $associationDetails[$associationType]
    );
    $association = $this->getAssociationWithDetails(
      $associationType,
      $typeDetails
    );

    return $association;
  }

  private function getAssociationDetails($association)
  {
    return $this->associations[$association];
  }

  private function getAssociationType($details)
  {
    $keys = array_keys($details);

    return $keys[0];
  }

  private function getAssociationTypeDetails($association, $type, $details)
  {
    switch ($type) {
      case 'belongsTo':
        return $this->getBelongsToDetails($association, $details);
        break;

      case 'belongsToMany':
        return $this->getBelongsToManyDetails($association, $details);
        break;

      case 'morphTo':
        return $this->getMorphToDetails($association, $details);
        break;

      default:
        return (array) $details;
        break;
    }
  }

  private function getBelongsToDetails($association, $details)
  {
    if(is_array($details) && count($details) > 2) return $details;

    $foreignKey = snake_case($association) . '_id';
    $related = $this->fetchKeyValue(0, (array) $details);

    return array($related, $foreignKey, $association);
  }

  private function getBelongsToManyDetails($association, $details)
  {
    $details = (array) $details;
    $related = $this->fetchKeyValue(0, $details);
    $table = $this->fetchKeyValue(1, $details);
    $foreignKey = $this->fetchKeyValue(2, $details);
    $otherKey = $this->fetchKeyValue(3, $details);

    return array(
      $related,
      $table,
      $foreignKey,
      $otherKey,
      $association
    );
  }

  private function getMorphToDetails($association, $details)
  {
    if(is_array($details) && count($details) >= 1) return $details;

    $details = (array) $details;

    $name = snake_case($association);
    $type = $this->fetchKeyValue(1, $details);
    $id = $this->fetchKeyValue(2, $details);

    return array($name, $type, $id);
  }

  private function fetchKeyValue($key, $array)
  {
    return array_key_exists($key, $array) ? $array[$key] : null;
  }


  private function getAssociationWithDetails($type, $details)
  {
    return call_user_func_array(
      array($this, $type),
      $details
    );
  }
}