<?php
/*
 +--------------------------------------------------------------------+
 | Copyright CiviCRM LLC. All rights reserved.                        |
 |                                                                    |
 | This work is published under the GNU AGPLv3 license with some      |
 | permitted exceptions and without any warranty. For full license    |
 | and copyright information, see https://civicrm.org/licensing       |
 +--------------------------------------------------------------------+
 */

/**
 * This class glues together the various parts of the extension
 * system.
 *
 * @package CRM
 * @copyright CiviCRM LLC https://civicrm.org/licensing
 */
class CRM_Extension_System {
  private static $singleton;

  private $cache = NULL;
  private $fullContainer = NULL;
  private $defaultContainer = NULL;
  private $mapper = NULL;
  private $manager = NULL;
  private $browser = NULL;
  private $downloader = NULL;

  /**
   * @var CRM_Extension_ClassLoader
   * */
  private $classLoader;

  /**
   * The URL of the remote extensions repository.
   *
   * @var string|false
   */
  private $_repoUrl = NULL;

  /**
   * @var array
   *   Construction parameters. These are primarily retained so
   *   that they can influence the cache name.
   */
  protected $parameters;

  /**
   * @param bool $fresh
   *   TRUE to force creation of a new system.
   *
   * @return CRM_Extension_System
   */
  public static function singleton($fresh = FALSE) {
    if (!self::$singleton || $fresh) {
      if (self::$singleton) {
        self::$singleton = new CRM_Extension_System(self::$singleton->parameters);
      }
      else {
        self::$singleton = new CRM_Extension_System();
      }
    }
    return self::$singleton;
  }

  /**
   * @param CRM_Extension_System $singleton
   *   The new, singleton extension system.
   */
  public static function setSingleton(CRM_Extension_System $singleton) {
    self::$singleton = $singleton;
  }

  /**
   * Class constructor.
   *
   * @param array $parameters
   *   List of configuration values required by the extension system.
   *   Missing values will be guessed based on $config.
   */
  public function __construct($parameters = []) {
    $config = CRM_Core_Config::singleton();
    $parameters['extensionsDir'] = CRM_Utils_Array::value('extensionsDir', $parameters, $config->extensionsDir);
    $parameters['extensionsURL'] = CRM_Utils_Array::value('extensionsURL', $parameters, $config->extensionsURL);
    $parameters['resourceBase'] = CRM_Utils_Array::value('resourceBase', $parameters, $config->resourceBase);
    $parameters['uploadDir'] = CRM_Utils_Array::value('uploadDir', $parameters, $config->uploadDir);
    $parameters['userFrameworkBaseURL'] = CRM_Utils_Array::value('userFrameworkBaseURL', $parameters, $config->userFrameworkBaseURL);
    if (!array_key_exists('civicrm_root', $parameters)) {
      $parameters['civicrm_root'] = $GLOBALS['civicrm_root'];
    }
    if (!array_key_exists('cmsRootPath', $parameters)) {
      $parameters['cmsRootPath'] = $config->userSystem->cmsRootPath();
    }
    if (!array_key_exists('domain_id', $parameters)) {
      $parameters['domain_id'] = CRM_Core_Config::domainID();
    }
    // guaranteed ordering - useful for md5(serialize($parameters))
    ksort($parameters);

    $this->parameters = $parameters;
  }

  /**
   * Get a container which represents all available extensions.
   *
   * @return CRM_Extension_Container_Interface
   */
  public function getFullContainer() {
    if ($this->fullContainer === NULL) {
      $containers = [];

      if ($this->getDefaultContainer()) {
        $containers['default'] = $this->getDefaultContainer();
      }

      $containers['civiroot'] = new CRM_Extension_Container_Basic(
        $this->parameters['civicrm_root'],
        $this->parameters['resourceBase'],
        $this->getCache(),
        'civiroot'
      );

      // TODO: CRM_Extension_Container_Basic( /sites/all/modules )
      // TODO: CRM_Extension_Container_Basic( /sites/$domain/modules
      // TODO: CRM_Extension_Container_Basic( /modules )
      // TODO: CRM_Extension_Container_Basic( /vendors )

      // At time of writing, D6, D7, and WP support cmsRootPath() but J does not
      if (NULL !== $this->parameters['cmsRootPath']) {
        $vendorPath = $this->parameters['cmsRootPath'] . DIRECTORY_SEPARATOR . 'vendor';
        if (is_dir($vendorPath)) {
          $containers['cmsvendor'] = new CRM_Extension_Container_Basic(
            $vendorPath,
            CRM_Utils_File::addTrailingSlash($this->parameters['userFrameworkBaseURL'], '/') . 'vendor',
            $this->getCache(),
            'cmsvendor'
          );
        }
      }

      if (!defined('CIVICRM_TEST')) {
        foreach ($containers as $container) {
          $container->addFilter([__CLASS__, 'isNotTestExtension']);
        }
      }

      $this->fullContainer = new CRM_Extension_Container_Collection($containers, $this->getCache(), 'full');
    }
    return $this->fullContainer;
  }

  /**
   * Get the container to which new extensions are installed.
   *
   * This container should be a particular, writeable directory.
   *
   * @return CRM_Extension_Container_Default|FALSE (false if not configured)
   */
  public function getDefaultContainer() {
    if ($this->defaultContainer === NULL) {
      if ($this->parameters['extensionsDir']) {
        $this->defaultContainer = new CRM_Extension_Container_Default($this->parameters['extensionsDir'], $this->parameters['extensionsURL'], $this->getCache(), 'default');
      }
      else {
        $this->defaultContainer = FALSE;
      }
    }
    return $this->defaultContainer;
  }

  /**
   * Get the service which provides runtime information about extensions.
   *
   * @return CRM_Extension_Mapper
   */
  public function getMapper() {
    if ($this->mapper === NULL) {
      $this->mapper = new CRM_Extension_Mapper($this->getFullContainer(), $this->getCache(), 'mapper');
    }
    return $this->mapper;
  }

  /**
   * @return \CRM_Extension_ClassLoader
   */
  public function getClassLoader() {
    if ($this->classLoader === NULL) {
      $this->classLoader = new CRM_Extension_ClassLoader($this->getMapper(), $this->getFullContainer(), $this->getManager());
    }
    return $this->classLoader;
  }

  /**
   * Get the service for enabling and disabling extensions.
   *
   * @return CRM_Extension_Manager
   */
  public function getManager() {
    if ($this->manager === NULL) {
      $typeManagers = [
        'payment' => new CRM_Extension_Manager_Payment($this->getMapper()),
        'report' => new CRM_Extension_Manager_Report(),
        'search' => new CRM_Extension_Manager_Search(),
        'module' => new CRM_Extension_Manager_Module($this->getMapper()),
      ];
      $this->manager = new CRM_Extension_Manager($this->getFullContainer(), $this->getDefaultContainer(), $this->getMapper(), $typeManagers);
    }
    return $this->manager;
  }

  /**
   * Get the service for finding remotely-available extensions
   *
   * @return CRM_Extension_Browser
   */
  public function getBrowser() {
    if ($this->browser === NULL) {
      $cacheDir = NULL;
      if (!empty($this->parameters['uploadDir'])) {
        $cacheDir = CRM_Utils_File::addTrailingSlash($this->parameters['uploadDir']) . 'cache';
      }
      $this->browser = new CRM_Extension_Browser($this->getRepositoryUrl(), '', $cacheDir);
    }
    return $this->browser;
  }

  /**
   * Get the service for loading code from remotely-available extensions
   *
   * @return CRM_Extension_Downloader
   */
  public function getDownloader() {
    if ($this->downloader === NULL) {
      $basedir = ($this->getDefaultContainer() ? $this->getDefaultContainer()->getBaseDir() : NULL);
      $this->downloader = new CRM_Extension_Downloader(
        $this->getManager(),
        $basedir,
        // WAS: $config->extensionsDir . DIRECTORY_SEPARATOR . 'tmp';
        CRM_Utils_File::tempdir()
      );
    }
    return $this->downloader;
  }

  /**
   * @return CRM_Utils_Cache_Interface
   */
  public function getCache() {
    if ($this->cache === NULL) {
      $cacheGroup = md5(serialize(['ext', $this->parameters, CRM_Utils_System::version()]));
      // Extension system starts before container. Manage our own cache.
      $this->cache = CRM_Utils_Cache::create([
        'name' => $cacheGroup,
        'type' => ['*memory*', 'SqlGroup', 'ArrayCache'],
        'prefetch' => TRUE,
      ]);
    }
    return $this->cache;
  }

  /**
   * Determine the URL which provides a feed of available extensions.
   *
   * @return string|FALSE
   */
  public function getRepositoryUrl() {
    if (empty($this->_repoUrl) && $this->_repoUrl !== FALSE) {
      $url = Civi::settings()->get('ext_repo_url');

      // boolean false means don't try to check extensions
      // CRM-10575
      if ($url === FALSE) {
        $this->_repoUrl = FALSE;
      }
      else {
        $this->_repoUrl = CRM_Utils_System::evalUrl($url);
      }
    }
    return $this->_repoUrl;
  }

  /**
   * Returns a list keyed by extension key
   *
   * @return array
   */
  public static function getCompatibilityInfo() {
    if (!isset(Civi::$statics[__CLASS__]['compatibility'])) {
      Civi::$statics[__CLASS__]['compatibility'] = json_decode(file_get_contents(Civi::paths()->getPath('[civicrm.root]/extension-compatibility.json')), TRUE);
    }
    return Civi::$statics[__CLASS__]['compatibility'];
  }

  public static function isNotTestExtension(CRM_Extension_Info $info) {
    return (bool) !preg_match('/^test\./', $info->key);
  }

  /**
   * Take an extension's raw XML info and add information about the
   * extension's status on the local system.
   *
   * The result format resembles the old CRM_Core_Extensions_Extension.
   *
   * @param CRM_Extension_Info $obj
   *
   * @return array
   */
  public static function createExtendedInfo(CRM_Extension_Info $obj) {
    $mapper = CRM_Extension_System::singleton()->getMapper();
    $manager = CRM_Extension_System::singleton()->getManager();

    $extensionRow = (array) $obj;
    try {
      $extensionRow['path'] = $mapper->keyToBasePath($obj->key);
    }
    catch (CRM_Extension_Exception $e) {
      $extensionRow['path'] = '';
    }
    $extensionRow['status'] = $manager->getStatus($obj->key);

    switch ($extensionRow['status']) {
      case CRM_Extension_Manager::STATUS_UNINSTALLED:
        // ts('Uninstalled');
        $extensionRow['statusLabel'] = '';
        break;

      case CRM_Extension_Manager::STATUS_DISABLED:
        $extensionRow['statusLabel'] = ts('Disabled');
        break;

      case CRM_Extension_Manager::STATUS_INSTALLED:
        // ts('Installed');
        $extensionRow['statusLabel'] = ts('Enabled');
        break;

      case CRM_Extension_Manager::STATUS_DISABLED_MISSING:
        $extensionRow['statusLabel'] = ts('Disabled (Missing)');
        break;

      case CRM_Extension_Manager::STATUS_INSTALLED_MISSING:
        // ts('Installed');
        $extensionRow['statusLabel'] = ts('Enabled (Missing)');
        break;

      default:
        $extensionRow['statusLabel'] = '(' . $extensionRow['status'] . ')';
    }
    if ($manager->isIncompatible($obj->key)) {
      $extensionRow['statusLabel'] = ts('Obsolete') . ($extensionRow['statusLabel'] ? (' - ' . $extensionRow['statusLabel']) : '');
    }
    return $extensionRow;
  }

}
