<?php

/**
 * This file is part of the LibrePanel project.
 * Copyright (c) 2010 the LibrePanel Team (see authors).
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you can also view it online at
 * https://files.librepanel.org/misc/COPYING.txt
 *
 * @copyright  the authors
 * @author     LibrePanel team <team@librepanel.org>
 * @license    https://files.librepanel.org/misc/COPYING.txt GPLv2
 */

namespace LibrePanel;

use Exception;
use LibrePanel\Api\Commands\Customers;
use LibrePanel\Api\Commands\SubDomains;
use LibrePanel\Database\Database;
use LibrePanel\UI\Collection;
use LibrePanel\UI\Response;
use RobThree\Auth\TwoFactorAuthException;

/**
 * Class to manage the current user / session
 */
class CurrentUser
{

	/**
	 * returns whether there is an active session
	 *
	 * @return bool
	 */
	public static function hasSession(): bool
	{
		return !empty($_SESSION) && !empty($_SESSION['userinfo']);
	}

	/**
	 * set userinfo field in session
	 *
	 * @param string $index
	 * @param mixed $data
	 *
	 * @return boolean
	 */
	public static function setField(string $index, $data): bool
	{
		$_SESSION['userinfo'][$index] = $data;
		return true;
	}

	/**
	 * re-read in the user data if a valid session exists
	 *
	 * @return bool
	 * @throws \Exception
	 */
	public static function reReadUserData(): bool
	{
		$table = self::isAdmin() ? TABLE_PANEL_ADMINS : TABLE_PANEL_CUSTOMERS;
		$userinfo_stmt = Database::prepare("
			SELECT * FROM `" . $table . "` WHERE `loginname`= :loginname AND `deactivated` = '0'
		");
		$userinfo = Database::pexecute_first($userinfo_stmt, [
			"loginname" => self::getField('loginname')
		]);
		if ($userinfo) {
			// don't just set the data, we need to merge with current data
			// array_merge is a right-reduction - value existing in getData() will be overwritten with $userinfo,
			// other than the union-operator (+) which would keep the values already existing from getData()
			$newuserinfo = array_merge(self::getData(), $userinfo);
			self::setData($newuserinfo);
			return true;
		}
		// unset / logout
		unset($_SESSION['userinfo']);
		self::setData([]);
		return false;
	}

	/**
	 * returns whether user has an adminsession
	 *
	 * @return bool
	 */
	public static function isAdmin(): bool
	{
		return (self::getField('adminsession') == 1 && self::getField('adminid') > 0 && empty(self::getField('customerid')));
	}

	/**
	 * return content of a given field from userinfo-array
	 *
	 * @param string $index
	 *
	 * @return string|array
	 */
	public static function getField(string $index)
	{
		return $_SESSION['userinfo'][$index] ?? "";
	}

	/**
	 * Return userinfo array
	 *
	 * @return array
	 */
	public static function getData(): array
	{
		return $_SESSION['userinfo'] ?? [];
	}

	/**
	 * set the userinfo data to the session
	 *
	 * @param array $data
	 */
	public static function setData(array $data = []): void
	{
		$_SESSION['userinfo'] = $data;
	}

	/**
	 * @param string $resource
	 * @return bool
	 * @throws \Exception
	 */
	public static function canAddResource(string $resource): bool
	{
		$addition = true;
		// special cases
		if ($resource == 'emails') {
			$result_stmt = Database::prepare("
				SELECT COUNT(`id`) as emaildomains
				FROM `" . TABLE_PANEL_DOMAINS . "`
				WHERE `customerid`= :cid AND `isemaildomain` = '1' AND `deactivated` = '0'
			");
			$result = Database::pexecute_first($result_stmt, [
				"cid" => $_SESSION['userinfo']['customerid']
			]);
			$addition = $result['emaildomains'] != 0;
		} elseif ($resource == 'subdomains') {
			if (Settings::IsInList('panel.customer_hide_options', 'domains')) {
				$addition = false;
			} else {
				$parentDomainCollection = (new Collection(
					SubDomains::class,
					$_SESSION['userinfo'],
					['sql_search' => [
						'd.parentdomainid' => 0,
						'd.deactivated' => 0,
						'd.id' => ['op' => '<>', 'value' => $_SESSION['userinfo']['standardsubdomain']]
					]
					]
				));
				$addition = $parentDomainCollection->count() != 0;
			}
		} elseif ($resource == 'domains') {
			$customerCollection = (new Collection(Customers::class, $_SESSION['userinfo']));
			$addition = $customerCollection->count() != 0;
		}

		return ($_SESSION['userinfo'][$resource . '_used'] < $_SESSION['userinfo'][$resource] || $_SESSION['userinfo'][$resource] == '-1') && $addition;
	}

	/**
	 * @throws TwoFactorAuthException
	 */
	public static function sendOtpEmail()
	{
		global $mail;

		if (self::getField('type_2fa') == 1) {
			// generate code
			$tfa = new LibrePanelTwoFactorAuth('LibrePanel ' . Settings::Get('system.hostname'));
			$secret = $tfa->createSecret();
			$code = $tfa->getCode($secret);
			// set code for user
			$table = TABLE_PANEL_CUSTOMERS;
			$uid = 'customerid';
			if (self::isAdmin()) {
				$table = TABLE_PANEL_ADMINS;
				$uid = 'adminid';
			}
			$stmt = Database::prepare("UPDATE $table SET `data_2fa` = :d2fa WHERE `$uid` = :uid");
			Database::pexecute($stmt, [
				"d2fa" => $secret,
				"uid" => self::getField($uid)
			]);
			// build up & send email
			$_mailerror = false;
			$mailerr_msg = "";
			$replace_arr = [
				'CODE' => $code
			];
			$mail_body = html_entity_decode(PhpHelper::replaceVariables(lng('mails.2fa.mailbody'), $replace_arr));

			try {
				$mail->Subject = lng('mails.2fa.subject');
				$mail->AltBody = $mail_body;
				$mail->MsgHTML(str_replace("\n", "<br />", $mail_body));
				$mail->AddAddress(self::getField('email'), User::getCorrectUserSalutation(self::getData()));
				$mail->Send();
			} catch (\PHPMailer\PHPMailer\Exception $e) {
				$mailerr_msg = $e->errorMessage();
				$_mailerror = true;
			} catch (Exception $e) {
				$mailerr_msg = $e->getMessage();
				$_mailerror = true;
			}

			if ($_mailerror) {
				$rstlog = LibrePanelLogger::getInstanceOf([
					'loginname' => '2fa code-sending'
				]);
				$rstlog->logAction(LibrePanelLogger::ADM_ACTION, LOG_ERR, "Error sending mail: " . $mailerr_msg);
				Response::redirectTo('index.php', [
					'showmessage' => '4',
					'customermail' => self::getField('email')
				]);
				exit();
			}

			$mail->ClearAddresses();
		}
	}
}