<?php

/**
 * @package     Joomla.Plugin
 * @subpackage  System.Webauthn
 *
 * @copyright   (C) 2020 Open Source Matters, Inc. <https://www.joomla.org>
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

namespace Joomla\Plugin\System\Webauthn\Extension;

use Joomla\CMS\Event\CoreEventAware;
use Joomla\CMS\Factory;
use Joomla\CMS\Log\Log;
use Joomla\CMS\Plugin\CMSPlugin;
use Joomla\Event\DispatcherInterface;
use Joomla\Event\SubscriberInterface;
use Joomla\Plugin\System\Webauthn\Authentication;
use Joomla\Plugin\System\Webauthn\PluginTraits\AdditionalLoginButtons;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandler;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerChallenge;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerCreate;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerDelete;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerInitCreate;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerLogin;
use Joomla\Plugin\System\Webauthn\PluginTraits\AjaxHandlerSaveLabel;
use Joomla\Plugin\System\Webauthn\PluginTraits\EventReturnAware;
use Joomla\Plugin\System\Webauthn\PluginTraits\UserDeletion;
use Joomla\Plugin\System\Webauthn\PluginTraits\UserProfileFields;

// phpcs:disable PSR1.Files.SideEffects
\defined('_JEXEC') or die;
// phpcs:enable PSR1.Files.SideEffects

/**
 * WebAuthn Passwordless Login plugin
 *
 * The plugin features are broken down into Traits for the sole purpose of making an otherwise
 * supermassive class somewhat manageable. You can find the Traits inside the Webauthn/PluginTraits
 * folder.
 *
 * @since  4.0.0
 */
final class Webauthn extends CMSPlugin implements SubscriberInterface
{
    // Add WebAuthn buttons
    use AdditionalLoginButtons;

    // AJAX request handlers
    use AjaxHandler;
    use AjaxHandlerInitCreate;
    use AjaxHandlerCreate;
    use AjaxHandlerSaveLabel;
    use AjaxHandlerDelete;
    use AjaxHandlerChallenge;
    use AjaxHandlerLogin;

    // Utility methods for setting the events' return values
    use EventReturnAware;
    use CoreEventAware;

    // Custom user profile fields
    use UserProfileFields;

    // Handle user profile deletion
    use UserDeletion;

    /**
     * Autoload the language files
     *
     * @var    boolean
     * @since  4.2.0
     */
    protected $autoloadLanguage = true;

    /**
     * Should I try to detect and register legacy event listeners, i.e. methods which accept unwrapped arguments? While
     * this maintains a great degree of backwards compatibility to Joomla! 3.x-style plugins it is much slower. You are
     * advised to implement your plugins using proper Listeners, methods accepting an AbstractEvent as their sole
     * parameter, for best performance. Also bear in mind that Joomla! 5.x onwards will only allow proper listeners,
     * removing support for legacy Listeners.
     *
     * @var    boolean
     * @since  4.2.0
     *
     * @deprecated  4.3 will be removed in 6.0
     *              Implement your plugin methods accepting an AbstractEvent object
     *              Example:
     *              onEventTriggerName(AbstractEvent $event) {
     *                  $context = $event->getArgument(...);
     *              }
     */
    protected $allowLegacyListeners = false;

    /**
     * The WebAuthn authentication helper object
     *
     * @var   Authentication
     * @since 4.2.0
     */
    protected $authenticationHelper;

    /**
     * Constructor. Loads the language files as well.
     *
     * @param   DispatcherInterface  $subject    The object to observe
     * @param   array                $config     An optional associative array of configuration
     *                                           settings. Recognized key values include 'name',
     *                                           'group', 'params', 'language (this list is not meant
     *                                           to be comprehensive).
     * @param   Authentication|null  $authHelper The WebAuthn helper object
     *
     * @since  4.0.0
     */
    public function __construct(&$subject, array $config = [], Authentication $authHelper = null)
    {
        parent::__construct($subject, $config);

        /**
         * Note: Do NOT try to load the language in the constructor. This is called before Joomla initializes the
         * application language. Therefore the temporary Joomla language object and all loaded strings in it will be
         * destroyed on application initialization. As a result we need to call loadLanguage() in each method
         * individually, even though all methods make use of language strings.
         */

        // Register a debug log file writer
        $logLevels = Log::ERROR | Log::CRITICAL | Log::ALERT | Log::EMERGENCY;

        if (\defined('JDEBUG') && JDEBUG) {
            $logLevels = Log::ALL;
        }

        Log::addLogger([
            'text_file'         => "webauthn_system.php",
            'text_entry_format' => '{DATETIME}	{PRIORITY} {CLIENTIP}	{MESSAGE}',
        ], $logLevels, ["webauthn.system"]);

        $this->authenticationHelper = $authHelper ?? (new Authentication());
        $this->authenticationHelper->setAttestationSupport($this->params->get('attestationSupport', 0) == 1);
    }

    /**
     * Returns the Authentication helper object
     *
     * @return Authentication
     *
     * @since  4.2.0
     */
    public function getAuthenticationHelper(): Authentication
    {
        return $this->authenticationHelper;
    }

    /**
     * Returns an array of events this subscriber will listen to.
     *
     * @return  array
     *
     * @since   4.2.0
     */
    public static function getSubscribedEvents(): array
    {
        try {
            $app = Factory::getApplication();
        } catch (\Exception $e) {
            return [];
        }

        if (!$app->isClient('site') && !$app->isClient('administrator')) {
            return [];
        }

        return [
            'onAjaxWebauthn'           => 'onAjaxWebauthn',
            'onAjaxWebauthnChallenge'  => 'onAjaxWebauthnChallenge',
            'onAjaxWebauthnCreate'     => 'onAjaxWebauthnCreate',
            'onAjaxWebauthnDelete'     => 'onAjaxWebauthnDelete',
            'onAjaxWebauthnInitcreate' => 'onAjaxWebauthnInitcreate',
            'onAjaxWebauthnLogin'      => 'onAjaxWebauthnLogin',
            'onAjaxWebauthnSavelabel'  => 'onAjaxWebauthnSavelabel',
            'onUserAfterDelete'        => 'onUserAfterDelete',
            'onUserLoginButtons'       => 'onUserLoginButtons',
            'onContentPrepareForm'     => 'onContentPrepareForm',
            'onContentPrepareData'     => 'onContentPrepareData',
        ];
    }
}