import express from 'express'
import {Issuer, generators} from 'openid-client'
import bodyParser from 'body-parser'

async function run() {
    const app = express();
    app.use(bodyParser.urlencoded());
    app.use(bodyParser.json())

    const issuer = await Issuer.discover(process.env.OIDC_GATEWAY_URL);
    console.log('Discovered issuer %s %O', issuer.issuer, issuer.metadata);
    const client = new issuer.Client({
        client_id: process.env.OIDC_CLIENT_ID,
        client_secret: process.env.OIDC_CLIENT_SECRET,
        redirect_uris: JSON.parse(process.env.OIDC_REDIRECT_URIS),
        response_types: ['code'],
        // id_token_signed_response_alg (default "RS256")
    })
    const code_verifier = generators.codeVerifier();
    const code_challenge = generators.codeChallenge(code_verifier);


    app.get('/', async function (req, res) {
        let url = client.authorizationUrl({
            redirect_uri: process.env.CLIENT_URL + '/cb',
            scope: 'openid profile',
            response_type: 'code',
            code_challenge,
            code_challenge_method: 'S256',
        });
        res.redirect(url);
    });
    app.get('/cb', async function (req, res) {
         const params = client.callbackParams(req);
        const tokenSet = await client.callback(process.env.CLIENT_URL + '/cb', params,{ code_verifier });
        const userinfo = await client.userinfo(tokenSet.access_token);
        console.log('userinfo %j', userinfo);
        res.send(userinfo)
    });


    app.listen(3000);
}

run().catch(console.dir);