const { prisma } = require('../../prisma');
const LnurlAuthService = require('../../auth/services/lnurlAuth.service')
const serverless = require('serverless-http');
const { createHash, associateTokenToHash } = require('../../auth/services/lnurlAuth.service');
const { createExpressApp } = require('../../modules');
const express = require('express');
const jose = require('jose');
const { JWT_SECRET } = require('../../utils/consts');
const { generatePrivateKey, getPublicKey } = require('../../utils/nostr-tools');
const { getUserByPubKey } = require('../../auth/utils/helperFuncs');



const loginHandler = async (req, res) => {

    const { tag, k1, sig, key, action, user_token } = req.query;

    if (tag !== 'login')
        return res.status(400).json({ status: 'ERROR', reason: 'Invalid Tag Provided' })
    // Verify login params 
    try {
        await LnurlAuthService.verifySig(sig, k1, key)
    } catch (error) {
        return res.status(400).json({ status: 'ERROR', reason: 'Invalid Signature' })

    }

    if (action === 'link' && user_token) {
        try {
            const { payload } = await jose.jwtVerify(user_token, Buffer.from(JWT_SECRET), {
                algorithms: ['HS256'],
            })
            const user_id = payload.user_id;
            const existingKeys = await prisma.userKey.findMany({ where: { user_id }, select: { key: true } });

            if (existingKeys.length >= 3)
                return res.status(400).json({ status: 'ERROR', reason: "Can only link up to 3 wallets" })

            if (!existingKeys.includes(key))
                await prisma.userKey.create({
                    data: {
                        key,
                        user_id,
                    }
                });

            // Remove old linking for this key if existing
            await prisma.userKey.deleteMany({
                where: { key }
            })

            return res
                .status(200)
                .json({ status: "OK" })

        } catch (error) {
            console.log(error);
            return res.status(400).json({ status: 'ERROR', reason: 'Invalid User Token' })
        }
    }


    try {
        //Create user if not already existing
        const user = await getUserByPubKey(key)
        if (user === null) {

            // Check if user had a previous account using this wallet

            const oldAccount = await prisma.user.findFirst({
                where: {
                    pubKey: key
                }
            });

            if (oldAccount) {
                await prisma.userKey.create({
                    data: {
                        key,
                        name: "My original wallet key",
                        user_id: oldAccount.id,
                    }
                });
            } else {
                const nostr_prv_key = generatePrivateKey();
                const nostr_pub_key = getPublicKey(nostr_prv_key);

                const createdUser = await prisma.user.create({
                    data: {
                        pubKey: key,
                        name: key,
                        avatar: `https://avatars.dicebear.com/api/bottts/${key}.svg`,
                        nostr_prv_key,
                        nostr_pub_key,
                    },
                })
                await prisma.userKey.create({
                    data: {
                        key,
                        name: "My original wallet key",
                        user_id: createdUser.id,
                    }
                });
            }

        }

        // calc the hash of k1
        const hash = createHash(k1);

        // generate the auth jwt token
        const hour = 3600000
        const maxAge = 30 * 24 * hour;

        const authToken = await new jose.SignJWT({ pubKey: key })
            .setProtectedHeader({ alg: 'HS256' })
            .setIssuedAt()
            .setExpirationTime(maxAge)
            //TODO: Set audience, issuer
            .sign(Buffer.from(JWT_SECRET, 'utf-8'))

        // associate the auth token with the hash in the db
        await associateTokenToHash(hash, authToken);


        return res.status(200).json({ status: "OK" })

    } catch (error) {
        console.log(error);
        return res.status(400).json({ status: 'ERROR', reason: 'Unexpected error happened, please try again' })
    }
}


let app;

if (process.env.LOCAL) {
    app = createExpressApp()
    app.get('/login', loginHandler);
}
else {
    const router = express.Router();
    router.get('/login', loginHandler)
    app = createExpressApp(router)
}


const handler = serverless(app);
exports.handler = async (event, context) => {
    return await handler(event, context);
};