EntityNG.php

<?php

/**
 * @file
 * Definition of Drupal\Core\Entity\EntityNG.
 */
namespace Drupal\Core\Entity;

use Drupal\Core\TypedData\ContextAwareInterface;
use Drupal\Core\TypedData\TypedDataInterface;
use Drupal\Component\Uuid\Uuid;
use ArrayIterator;
use InvalidArgumentException;

/**
 * Implements Entity Field API specific enhancements to the Entity class.
 *
 * An entity implements the ComplexDataInterface, thus is complex data
 * containing fields as its data properties. The entity fields have to implement
 * the \Drupal\Core\Entity\Field\FieldInterface.
 *
 * @todo: Once all entity types have been converted, merge improvements into the
 * Entity class and overhaul the EntityInterface.
 */
class EntityNG extends Entity {

  /**
   * The plain data values of the contained fields.
   *
   * This always holds the original, unchanged values of the entity. The values
   * are keyed by language code, whereas LANGUAGE_NOT_SPECIFIED is used for
   * values in default language.
   *
   * @todo: Add methods for getting original fields and for determining
   * changes.
   * @todo: Provide a better way for defining default values.
   *
   * @var array
   */
  protected $values = array(
    'langcode' => array(
      LANGUAGE_DEFAULT => array(
        0 => array(
          'value' => LANGUAGE_NOT_SPECIFIED,
        ),
      ),
    ),
  );

  /**
   * The array of fields, each being an instance of FieldInterface.
   *
   * @var array
   */
  protected $fields = array();

  /**
   * Whether the entity is in pre-Entity Field API compatibility mode.
   *
   * If set to TRUE, field values are written directly to $this->values, thus
   * must be plain property values keyed by language code. This must be enabled
   * when calling legacy field API attachers.
   *
   * @var bool
   */
  protected $compatibilityMode = FALSE;

  /**
   * Overrides Entity::id().
   */
  public function id() {
    return $this
      ->get('id')->value;
  }

  /**
   * Overrides Entity::uuid().
   */
  public function uuid() {
    return $this
      ->get('uuid')->value;
  }

  /**
   * Implements ComplexDataInterface::get().
   */
  public function get($property_name) {

    // Values in default language are always stored using the LANGUAGE_DEFAULT
    // constant.
    if (!isset($this->fields[$property_name][LANGUAGE_DEFAULT])) {
      return $this
        ->getTranslatedField($property_name, LANGUAGE_DEFAULT);
    }
    return $this->fields[$property_name][LANGUAGE_DEFAULT];
  }

  /**
   * Gets a translated field.
   *
   * @return \Drupal\Core\Entity\Field\FieldInterface
   */
  protected function getTranslatedField($property_name, $langcode) {

    // Populate $this->properties to fasten further lookups and to keep track of
    // property objects, possibly holding changes to properties.
    if (!isset($this->fields[$property_name][$langcode])) {
      $definition = $this
        ->getPropertyDefinition($property_name);
      if (!$definition) {
        throw new InvalidArgumentException('Field ' . check_plain($property_name) . ' is unknown.');
      }

      // Non-translatable properties always use default language.
      if ($langcode != LANGUAGE_DEFAULT && empty($definition['translatable'])) {
        $this->fields[$property_name][$langcode] = $this
          ->getTranslatedField($property_name, LANGUAGE_DEFAULT);
      }
      else {
        $value = isset($this->values[$property_name][$langcode]) ? $this->values[$property_name][$langcode] : NULL;
        $context = array(
          'parent' => $this,
          'name' => $property_name,
        );
        $this->fields[$property_name][$langcode] = typed_data()
          ->create($definition, $value, $context);
      }
    }
    return $this->fields[$property_name][$langcode];
  }

  /**
   * Implements ComplexDataInterface::set().
   */
  public function set($property_name, $value) {
    $this
      ->get($property_name)
      ->setValue($value);
  }

  /**
   * Implements ComplexDataInterface::getProperties().
   */
  public function getProperties($include_computed = FALSE) {
    $properties = array();
    foreach ($this
      ->getPropertyDefinitions() as $name => $definition) {
      if ($include_computed || empty($definition['computed'])) {
        $properties[$name] = $this
          ->get($name);
      }
    }
    return $properties;
  }

  /**
   * Implements IteratorAggregate::getIterator().
   */
  public function getIterator() {
    return new ArrayIterator($this
      ->getProperties());
  }

  /**
   * Implements ComplexDataInterface::getPropertyDefinition().
   */
  public function getPropertyDefinition($name) {

    // First try getting property definitions which apply to all entities of
    // this type. Then if this fails add in definitions of optional properties
    // as well. That way we can use property definitions of base properties
    // when determining the optional properties of an entity.
    $definitions = entity_get_controller($this->entityType)
      ->getFieldDefinitions(array());
    if (isset($definitions[$name])) {
      return $definitions[$name];
    }

    // Add in optional properties if any.
    if ($definitions = $this
      ->getPropertyDefinitions()) {
      return isset($definitions[$name]) ? $definitions[$name] : FALSE;
    }
  }

  /**
   * Implements ComplexDataInterface::getPropertyDefinitions().
   */
  public function getPropertyDefinitions() {
    return entity_get_controller($this->entityType)
      ->getFieldDefinitions(array(
      'entity type' => $this->entityType,
      'bundle' => $this
        ->bundle(),
    ));
  }

  /**
   * Implements ComplexDataInterface::getPropertyValues().
   */
  public function getPropertyValues() {
    $values = array();
    foreach ($this
      ->getProperties() as $name => $property) {
      $values[$name] = $property
        ->getValue();
    }
    return $values;
  }

  /**
   * Implements ComplexDataInterface::setPropertyValues().
   */
  public function setPropertyValues($values) {
    foreach ($values as $name => $value) {
      $this
        ->get($name)
        ->setValue($value);
    }
  }

  /**
   * Implements ComplexDataInterface::isEmpty().
   */
  public function isEmpty() {
    if (!$this
      ->isNew()) {
      return FALSE;
    }
    foreach ($this
      ->getProperties() as $property) {
      if ($property
        ->getValue() !== NULL) {
        return FALSE;
      }
    }
    return TRUE;
  }

  /**
   * Implements TranslatableInterface::language().
   */
  public function language() {
    return $this
      ->get('langcode')->language;
  }

  /**
   * Implements TranslatableInterface::getTranslation().
   *
   * @return \Drupal\Core\Entity\Field\Type\EntityTranslation
   */
  public function getTranslation($langcode, $strict = TRUE) {

    // If the default language is LANGUAGE_NOT_SPECIFIED, the entity is not
    // translatable, so we use LANGUAGE_DEFAULT.
    if ($langcode == LANGUAGE_DEFAULT || in_array($this
      ->language()->langcode, array(
      LANGUAGE_NOT_SPECIFIED,
      $langcode,
    ))) {

      // No translation needed, return the entity.
      return $this;
    }

    // Check whether the language code is valid, thus is of an available
    // language.
    $languages = language_list(LANGUAGE_ALL);
    if (!isset($languages[$langcode])) {
      throw new InvalidArgumentException("Unable to get translation for the invalid language '{$langcode}'.");
    }
    $fields = array();
    foreach ($this
      ->getPropertyDefinitions() as $name => $definition) {

      // Load only translatable properties in strict mode.
      if (!empty($definition['translatable']) || !$strict) {
        $fields[$name] = $this
          ->getTranslatedField($name, $langcode);
      }
    }
    $translation_definition = array(
      'type' => 'entity_translation',
      'constraints' => array(
        'entity type' => $this
          ->entityType(),
        'bundle' => $this
          ->bundle(),
      ),
    );
    $translation = typed_data()
      ->create($translation_definition, $fields, array(
      'parent' => $this,
      'name' => $langcode,
    ));
    $translation
      ->setStrictMode($strict);
    return $translation;
  }

  /**
   * Implements TranslatableInterface::getTranslationLanguages().
   */
  public function getTranslationLanguages($include_default = TRUE) {
    $translations = array();

    // Build an array with the translation langcodes set as keys.
    foreach ($this
      ->getProperties() as $name => $property) {
      if (isset($this->values[$name])) {
        $translations += $this->values[$name];
      }
      $translations += $this->fields[$name];
    }
    unset($translations[LANGUAGE_DEFAULT]);
    if ($include_default) {
      $translations[$this
        ->language()->langcode] = TRUE;
    }

    // Now get languages based upon translation langcodes. Empty languages must
    // be filtered out as they concern empty/unset properties.
    $languages = array_intersect_key(language_list(LANGUAGE_ALL), array_filter($translations));
    return $languages;
  }

  /**
   * Enables or disable the compatibility mode.
   *
   * @param bool $enabled
   *   Whether to enable the mode.
   *
   * @see EntityNG::compatibilityMode
   */
  public function setCompatibilityMode($enabled) {
    $this->compatibilityMode = (bool) $enabled;
    if ($enabled) {
      $this
        ->updateOriginalValues();
      $this->fields = array();
    }
  }

  /**
   * Returns whether the compatibility mode is active.
   */
  public function getCompatibilityMode() {
    return $this->compatibilityMode;
  }

  /**
   * Updates the original values with the interim changes.
   *
   * Note: This should be called by the storage controller during a save
   * operation.
   */
  public function updateOriginalValues() {
    foreach ($this->fields as $name => $properties) {
      foreach ($properties as $langcode => $property) {
        $this->values[$name][$langcode] = $property
          ->getValue();
      }
    }
  }

  /**
   * Magic getter: Gets the property in default language.
   *
   * For compatibility mode to work this must return a reference.
   */
  public function &__get($name) {
    if ($this->compatibilityMode) {
      if (!isset($this->values[$name])) {
        $this->values[$name] = NULL;
      }
      return $this->values[$name];
    }
    if (isset($this->fields[$name][LANGUAGE_DEFAULT])) {
      return $this->fields[$name][LANGUAGE_DEFAULT];
    }
    if ($this
      ->getPropertyDefinition($name)) {
      $return = $this
        ->get($name);
      return $return;
    }
    if (!isset($this->{$name})) {
      $this->{$name} = NULL;
    }
    return $this->{$name};
  }

  /**
   * Magic getter: Sets the property in default language.
   */
  public function __set($name, $value) {

    // Support setting values via property objects.
    if ($value instanceof TypedDataInterface) {
      $value = $value
        ->getValue();
    }
    if ($this->compatibilityMode) {
      $this->values[$name] = $value;
    }
    elseif (isset($this->fields[$name][LANGUAGE_DEFAULT])) {
      $this->fields[$name][LANGUAGE_DEFAULT]
        ->setValue($value);
    }
    elseif ($this
      ->getPropertyDefinition($name)) {
      $this
        ->get($name)
        ->setValue($value);
    }
    else {
      $this->{$name} = $value;
    }
  }

  /**
   * Magic method.
   */
  public function __isset($name) {
    if ($this->compatibilityMode) {
      return isset($this->values[$name]);
    }
    elseif ($this
      ->getPropertyDefinition($name)) {
      return (bool) count($this
        ->get($name));
    }
  }

  /**
   * Magic method.
   */
  public function __unset($name) {
    if ($this->compatibilityMode) {
      unset($this->values[$name]);
    }
    elseif ($this
      ->getPropertyDefinition($name)) {
      $this
        ->get($name)
        ->setValue(array());
    }
  }

  /**
   * Overrides Entity::createDuplicate().
   */
  public function createDuplicate() {
    $duplicate = clone $this;
    $entity_info = $this
      ->entityInfo();
    $duplicate->{$entity_info['entity_keys']['id']}->value = NULL;

    // Check if the entity type supports UUIDs and generate a new one if so.
    if (!empty($entity_info['entity_keys']['uuid'])) {
      $uuid = new Uuid();
      $duplicate->{$entity_info['entity_keys']['uuid']}->value = $uuid
        ->generate();
    }
    return $duplicate;
  }

  /**
   * Implements a deep clone.
   */
  public function __clone() {
    foreach ($this->fields as $name => $properties) {
      foreach ($properties as $langcode => $property) {
        $this->fields[$name][$langcode] = clone $property;
        if ($property instanceof ContextAwareInterface) {
          $this->fields[$name][$langcode]
            ->setParent($this);
        }
      }
    }
  }

}