<?php
/**
 * @copyright 2018, Roeland Jago Douma <roeland@famdouma.nl>
 *
 * @author Bjoern Schiessle <bjoern@schiessle.org>
 * @author Roeland Jago Douma <roeland@famdouma.nl>
 *
 * @license GNU AGPL version 3 or any later version
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 */
namespace OC\AppFramework\Middleware\Security;

use OC\AppFramework\Middleware\Security\Exceptions\NotConfirmedException;
use OC\AppFramework\Utility\ControllerMethodReflector;
use OC\Authentication\Token\IProvider;
use OCP\AppFramework\Controller;
use OCP\AppFramework\Http\Attribute\PasswordConfirmationRequired;
use OCP\AppFramework\Middleware;
use OCP\AppFramework\Utility\ITimeFactory;
use OCP\Authentication\Exceptions\ExpiredTokenException;
use OCP\Authentication\Exceptions\InvalidTokenException;
use OCP\Authentication\Exceptions\WipeTokenException;
use OCP\ISession;
use OCP\IUserSession;
use OCP\Session\Exceptions\SessionNotAvailableException;
use OCP\User\Backend\IPasswordConfirmationBackend;
use ReflectionMethod;

class PasswordConfirmationMiddleware extends Middleware {
	/** @var ControllerMethodReflector */
	private $reflector;
	/** @var ISession */
	private $session;
	/** @var IUserSession */
	private $userSession;
	/** @var ITimeFactory */
	private $timeFactory;
	/** @var array */
	private $excludedUserBackEnds = ['user_saml' => true, 'user_globalsiteselector' => true];
	private IProvider $tokenProvider;

	/**
	 * PasswordConfirmationMiddleware constructor.
	 *
	 * @param ControllerMethodReflector $reflector
	 * @param ISession $session
	 * @param IUserSession $userSession
	 * @param ITimeFactory $timeFactory
	 */
	public function __construct(ControllerMethodReflector $reflector,
		ISession $session,
		IUserSession $userSession,
		ITimeFactory $timeFactory,
		IProvider $tokenProvider,
	) {
		$this->reflector = $reflector;
		$this->session = $session;
		$this->userSession = $userSession;
		$this->timeFactory = $timeFactory;
		$this->tokenProvider = $tokenProvider;
	}

	/**
	 * @param Controller $controller
	 * @param string $methodName
	 * @throws NotConfirmedException
	 */
	public function beforeController($controller, $methodName) {
		$reflectionMethod = new ReflectionMethod($controller, $methodName);

		if ($this->hasAnnotationOrAttribute($reflectionMethod, 'PasswordConfirmationRequired', PasswordConfirmationRequired::class)) {
			$user = $this->userSession->getUser();
			$backendClassName = '';
			if ($user !== null) {
				$backend = $user->getBackend();
				if ($backend instanceof IPasswordConfirmationBackend) {
					if (!$backend->canConfirmPassword($user->getUID())) {
						return;
					}
				}

				$backendClassName = $user->getBackendClassName();
			}

			try {
				$sessionId = $this->session->getId();
				$token = $this->tokenProvider->getToken($sessionId);
			} catch (SessionNotAvailableException|InvalidTokenException|WipeTokenException|ExpiredTokenException) {
				// States we do not deal with here.
				return;
			}
			$scope = $token->getScopeAsArray();
			if (isset($scope['password-unconfirmable']) && $scope['password-unconfirmable'] === true) {
				// Users logging in from SSO backends cannot confirm their password by design
				return;
			}

			$lastConfirm = (int) $this->session->get('last-password-confirm');
			// TODO: confirm excludedUserBackEnds can go away and remove it
			if (!isset($this->excludedUserBackEnds[$backendClassName]) && $lastConfirm < ($this->timeFactory->getTime() - (30 * 60 + 15))) { // allow 15 seconds delay
				throw new NotConfirmedException();
			}
		}
	}

	/**
	 * @template T
	 *
	 * @param ReflectionMethod $reflectionMethod
	 * @param string $annotationName
	 * @param class-string<T> $attributeClass
	 * @return boolean
	 */
	protected function hasAnnotationOrAttribute(ReflectionMethod $reflectionMethod, string $annotationName, string $attributeClass): bool {
		if (!empty($reflectionMethod->getAttributes($attributeClass))) {
			return true;
		}

		if ($this->reflector->hasAnnotation($annotationName)) {
			return true;
		}

		return false;
	}
}