/*
 * MHSF, Minehut Server List
 * All external content is rather licensed under the ECA Agreement
 * located here: https://mhsf.app/docs/legal/external-content-agreement
 *
 * All code under MHSF is licensed under the MIT License
 * by open source contributors
 *
 * Copyright (c) 2025 dvelo
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

import { auth, getAuth } from "@clerk/nextjs/server";
import { NextApiRequest, NextApiResponse } from "next";
import { MongoClient } from "mongodb"
import jwt from "jsonwebtoken"

export default async function handler(
    req: NextApiRequest,
    res: NextApiResponse
) {
    const { userId } = getAuth(req)

    if (!userId) {
      return res.status(401).json({ error: 'Unauthorized' })
    }

    const client = new MongoClient(process.env.MONGO_DB as string);
    await client.connect();

    const collection = client.db("mhsf").collection("migrations")
    const find = await collection.find({oldUserId: userId}).toArray()
    if (find.length !== 0) {
        return res.json({validationToken: jwt.sign({userId, exp: Math.floor(Date.now() / 1000) + (60 * 60)}, find[0].secret)})
    }
    const secret = createRandomString(60)
    await collection.insertOne({oldUserId: userId, secret, date: Date.now()})

    res.send({validationToken: jwt.sign({userId, exp: Math.floor(Date.now() / 1000) + (60 * 60)}, secret)})
}

function createRandomString(length: number) {
    const chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
    let result = "";
    for (let i = 0; i < length; i++) {
        result += chars.charAt(Math.floor(Math.random() * chars.length));
    }
    return result;
}