<?php
/**
 * Copyright (C) 2010-2017  Tim Düsterhus
 * Copyright (C) 2010-2017  Woltlab GmbH
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

namespace chat\system\permission;

use \wcf\system\acl\ACLHandler;
use \wcf\system\user\storage\UserStorageHandler;
use \wcf\system\WCF;

/**
 * Handles chat permissions.
 */
class PermissionHandler {
	/**
	 * permissions set for the given user
	 * @var	boolean[]
	 */
	protected $chatPermissions = [ ];

	/**
	 * given user decorated in a user profile
	 * @var \wcf\data\user\UserProfile
	 */
	protected $user = null;

	/**
	 * Cache of PermissionHandlers.
	 * @var \chat\system\permission\PermissionHandler[]
	 */
	protected static $cache = [ ];

	public function __construct(\wcf\data\user\UserProfile $user = null) {
		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());
		$this->user = $user;

		$this->chatPermissions = \chat\system\cache\builder\PermissionCacheBuilder::getInstance()->getData($user->getGroupIDs());

		// get user permissions
		if ($user->userID) {
			$ush = UserStorageHandler::getInstance();

			// get ids
			$data = $ush->getField('chatUserPermissions', $user->userID);

			// cache does not exist or is outdated
			if ($data === null) {
				$userPermissions = [ ];

				$conditionBuilder = new \wcf\system\database\util\PreparedStatementConditionBuilder();
				$conditionBuilder->add('acl_option.objectTypeID = ?', [ ACLHandler::getInstance()->getObjectTypeID('be.bastelstu.chat.room') ]);
				$conditionBuilder->add('option_to_user.userID = ?', [ $user->userID ]);
				$sql = "SELECT     option_to_user.objectID AS roomID,
				                   option_to_user.optionValue,
				                   acl_option.optionName AS permission
				        FROM       wcf".WCF_N."_acl_option acl_option
				        INNER JOIN wcf".WCF_N."_acl_option_to_user option_to_user
				                   ON option_to_user.optionID = acl_option.optionID
				        ".$conditionBuilder;
				$statement = WCF::getDB()->prepareStatement($sql);
				$statement->execute($conditionBuilder->getParameters());
				while (($row = $statement->fetchArray())) {
					$userPermissions[$row['roomID']][$row['permission']] = $row['optionValue'];
				}

				// update cache
				$ush->update($user->userID, 'chatUserPermissions', serialize($userPermissions));
			}
			else {
				$userPermissions = unserialize($data);
			}

			foreach ($userPermissions as $roomID => $permissions) {
				foreach ($permissions as $name => $value) {
					$this->chatPermissions[$roomID][$name] = $value;
				}
			}
		}
	}

	public static function get(\wcf\data\user\UserProfile $user = null) {
		if ($user === null) $user = new \wcf\data\user\UserProfile(WCF::getUser());
		if (!isset(static::$cache[$user->userID])) {
			static::$cache[$user->userID] = new static($user);
		}

		return static::$cache[$user->userID];
	}

	/**
	 * Fetches the given permission for the given room
	 *
	 * @param	\chat\data\room\Room	$room
	 * @param	string			$permission
	 * @return	boolean
	 */
	public function getPermission(\chat\data\room\Room $room, $permission) {
		$groupPermission = str_replace([ 'user.', 'mod.' ], [ 'user.chat.', 'mod.chat.' ], $permission);

		if (method_exists($this->user, 'getNeverPermission') && $this->user->getNeverPermission($groupPermission)) {
			return false;
		}

		if (!isset($this->chatPermissions[$room->roomID][$permission])) {
			return $this->user->getPermission($groupPermission);
		}
		return (boolean) $this->chatPermissions[$room->roomID][$permission];
	}

	/**
	 * Clears the cache.
	 */
	public static function resetCache() {
		UserStorageHandler::getInstance()->resetAll('chatUserPermissions');
		\chat\system\cache\builder\PermissionCacheBuilder::getInstance()->reset();
	}
}