<?php
/**
 * SPDX-FileCopyrightText: 2024 Sascha Nitsch (grumpydeveloper) https://contentnation.net/@grumpydevelop
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * @author Sascha Nitsch (grumpydeveloper)
 **/

namespace Federator\DIO;

/**
 * IO functions related to users
 */
class User
{
    /**
     * add local user based on given user object received from remote service
     * @param \mysqli $dbh database handle
     * @param \Federator\Data\User $user user object to use
     * @param string $_user user/profile name
     * @return void
     */
    protected static function addLocalUser($dbh, $user, $_user)
    {
        echo "a new user\n";
        // needed fields: RSA key pair, user name (handle)

        $private_key = openssl_pkey_new();
        if ($private_key === false) {
            throw new \Federator\Exceptions\ServerError();
        }
        $public = openssl_pkey_get_details($private_key)['key'];
        $private = '';
        openssl_pkey_export($private_key, $private);
        $sql = 'insert into users (id, externalid, rsapublic, rsaprivate) values (?, ?, ?, ?)';
        $stmt = $dbh->prepare($sql);
        if ($stmt === false) {
            throw new \Federator\Exceptions\ServerError();
        }
        $stmt->bind_param("ssss", $_user, $user->externalid, $public, $private);
        $stmt->execute();
        $stmt->close();
    }

    /**
     * extend the given user with internal data
     * @param \mysqli $dbh database  handle
     * @param \Federator\Data\User $user user to extend
     * @param string $_user user/profile name
     */
    protected static function extendUser(\mysqli $dbh, $user, $_user) : void
    {
        $sql = 'select id from users where id=?';
        $stmt = $dbh->prepare($sql);
        if ($stmt === false) {
            throw new \Federator\Exceptions\ServerError();
        }
        $stmt->bind_param("s", $_user);
        $ret = $stmt->bind_result($user->id);
        $stmt->execute();
        if ($ret) {
            $stmt->fetch();
        }
        $stmt->close();
        // if a new user, create own database entry with additionally needed info
        if ($user->id === null) {
            self::addLocalUser($dbh, $user, $_user);
        }

        // no further processing for now
    }

    /**
     * get User by session id
     *
     * @param \mysqli $dbh
     *          database handle
     * @param string $_session
     *          session
     * @param string $_user
     *          user/profile name
     * @param \Federator\Connector\Connector $connector
     *          connector to fetch use with
     * @param \Federator\Cache\Cache|null $cache
     *          optional caching service
     * @return \Federator\Data\User|false
     */
    public static function getUserBySession($dbh, $_session, $_user, $connector, $cache)
    {
        $saveToCache = false;
        $user = false;
        if ($cache !== null) {
            $user = $cache->getRemoteUserBySession($_session, $_user);
        }

        if ($user === false) {
            // ask connector for user-id
            $user = $connector->getRemoteUserBySession($_session, $_user);
            $saveToCache = true;
        }
        if ($user === false) {
            return false;
        }
        self::extendUser($dbh, $user, $_user);
        if ($cache !== null && $saveToCache) {
            $cache->saveRemoteUserBySession($_session, $_user, $user);
        }
        return $user;
    }
}