<?php

namespace Drupal\libraries\ExternalLibrary\Asset;

use Drupal\Component\Plugin\Factory\FactoryInterface;
use Drupal\libraries\ExternalLibrary\Exception\LibraryNotInstalledException;
use Drupal\libraries\ExternalLibrary\LibraryBase;
use Drupal\libraries\ExternalLibrary\LibraryManagerInterface;
use Drupal\libraries\ExternalLibrary\Local\LocalLibraryInterface;
use Drupal\libraries\ExternalLibrary\Local\LocalLibraryTrait;
use Drupal\libraries\ExternalLibrary\Remote\RemoteLibraryInterface;
use Drupal\libraries\ExternalLibrary\Remote\RemoteLibraryTrait;
use Drupal\libraries\ExternalLibrary\Type\LibraryTypeInterface;

/**
 * Provides a class for a single attachable asset library.
 */
class AssetLibrary extends LibraryBase implements
  AssetLibraryInterface,
  LocalLibraryInterface,
  RemoteLibraryInterface
{

  use
    LocalLibraryTrait,
    RemoteLibraryTrait,
    LocalRemoteAssetTrait
  ;

  /**
   * An array containing the CSS assets of the library.
   *
   * @var array
   */
  protected $cssAssets = [];

  /**
   * An array containing the JavaScript assets of the library.
   *
   * @var array
   */
  protected $jsAssets = [];

  /**
   * An array of attachable asset library IDs that this library depends on.
   *
   * @todo Explain the difference to regular dependencies.
   */
  protected $attachableDependencies = [];

  /**
   * Construct an external library.
   *
   * @param string $id
   *   The library ID.
   * @param array $definition
   *   The library definition array.
   * @param \Drupal\libraries\ExternalLibrary\Type\LibraryTypeInterface $library_type
   *   The library type of the library.
   */
  public function __construct($id, array $definition, LibraryTypeInterface $library_type) {
    parent::__construct($id, $definition, $library_type);
    $this->remoteUrl = $definition['remote_url'];
    $this->cssAssets = $definition['css'];
    $this->jsAssets = $definition['js'];
    $this->attachableDependencies = $definition['attachable_dependencies'];
  }

  /**
   * {@inheritdoc}
   */
  protected static function processDefinition(array &$definition) {
    parent::processDefinition($definition);
    $definition += [
      'remote_url' => '',
      'css' => [],
      'js' => [],
      'attachable_dependencies' => [],
    ];
  }

  /**
   * Returns a core library array structure for this library.
   *
   * @param \Drupal\libraries\ExternalLibrary\LibraryManagerInterface $library_manager
   *   The library manager that can be used to fetch dependencies.
   *
   * @return array
   *
   * @see \Drupal\libraries\ExternalLibrary\Asset\getAttachableAssetLibraries::getAttachableAssetLibraries()
   *
   * @throws \Drupal\libraries\ExternalLibrary\Exception\InvalidLibraryDependencyException
   * @throws \Drupal\libraries\ExternalLibrary\Exception\LibraryDefinitionNotFoundException
   * @throws \Drupal\libraries\ExternalLibrary\Exception\LibraryTypeNotFoundException
   * @throws \Drupal\Component\Plugin\Exception\PluginException
   *
   * @todo Document the return value.
   */
  public function getAttachableAssetLibrary(LibraryManagerInterface $library_manager) {
    if (!$this->canBeAttached()) {
      throw new LibraryNotInstalledException($this);
    }
    return [
      'version' => $this->getVersion(),
      'css' => $this->processCssAssets($this->cssAssets),
      'js' => $this->processJsAssets($this->jsAssets),
      'dependencies' => $this->attachableDependencies,
    ];
  }

  /**
   * Gets the locator of this library using the locator factory.
   *
   * @param \Drupal\Component\Plugin\Factory\FactoryInterface $locator_factory
   *
   * @return \Drupal\libraries\ExternalLibrary\Local\LocatorInterface
   *
   * @see \Drupal\libraries\ExternalLibrary\Local\LocalLibraryInterface::getLocator()
   */
  public function getLocator(FactoryInterface $locator_factory) {
    // @todo Consider consolidating the stream wrappers used here. For now we
    // allow asset libs to live almost anywhere.
    return $locator_factory->createInstance('chain')
      ->addLocator($locator_factory->createInstance('uri', ['uri' => 'asset://']))
      ->addLocator($locator_factory->createInstance('uri', ['uri' => 'php-file://']));
  }

}